Purpose Our purpose was to compare the difference between hot-air dried American ginseng(HDAG)(Panacis Quinquefolii Radix)and freeze-dried American ginseng(FDAG)(Panacis Quinquefolii Radix)and provide a better drying ...Purpose Our purpose was to compare the difference between hot-air dried American ginseng(HDAG)(Panacis Quinquefolii Radix)and freeze-dried American ginseng(FDAG)(Panacis Quinquefolii Radix)and provide a better drying approach for improv-ing the quality of American ginseng(Panacis Quinquefolii Radix).Methods In our present study,we compared the appearance features of HDAG and FDAG using a CR-410 colorimeter and scanning electron microscopy.Furthermore,we qualitatively and quantitatively determined ginsenosides in HDAG and FDAG by using UPLC-Q Exactive Orbitrap-MS/MS and high-performance liquid chromatography.Results Our present results showed that compared to the hot-air drying method,freeze-drying(FD)has obvious advantages in not only good appearances but also higher bioactive constituents for drying the American ginseng(Panacis Quinquefolii Radix).Conclusion FD is beneficial for the retention of ginsenosides in American ginseng(Panacis Quinquefolii Radix)and also helpful for maintaining the bioactive effects of this functional food.展开更多
Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, re...Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, reduction of graphene oxide and loading of Ag/TiO2nanoparticles on graphene sheets were achieved. Investigation of chemical state of products showed that covering of Ag/TiO2surface with higher weight ratio of graphene resulting in that Ag metals in Ag/TiO2were oxidized to Ag2 O in nanocomposite structure after solvothermal process. Degree of photocatalytic activity enhancement strongly depends on the coverage of Ag/TiO2surface by porous graphene. The sample of 1 wt% porous graphene hybridized Ag/TiO2showed the highest photocatalytic activity, which is related to high migration efficiency of photoinduced of electrons and reduction of electron–hole recombination rate due to high electrical conductivity of graphene. Expanding of absorption to visible light region was ascribed to surface plasmon resonance effect of Ag metals and presence of graphene. Investigation of photocatalytic performance of formic acid as a dye-less organic pollutant showed that dye sensitization effect of Rh B molecules during evaluation of photocatalytic performance was negligible.展开更多
AIM: To investigate the antifibrotic effect of freeze-dried bilayered fibrin-binding amniotic membrane on trabeculectomy in a rabbit model. METHODS: Twenty-four Japanese white rabbits were randomized into three groups...AIM: To investigate the antifibrotic effect of freeze-dried bilayered fibrin-binding amniotic membrane on trabeculectomy in a rabbit model. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with natural bilayered fibrin-binding amniotic membrane) and the blank group (single trabeculectomy). Clinical observation, hematoxylin-eosin staining, Massion staining, real-time PCR and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. RESULTS: Statistical differences were noted in survival. analysis and intraocular pressure(IOP) among groups on days 7, 14, 21 and 30 following surgery. Histology, immunohistochemistry and real-time PCR further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane resulted in good wound healing and no scar formation. CONCLUSION: Self-made freeze-dried bilayered fibrin-binding amniotic membrane may inhibit the formation of scarring in glaucoma after trabeculectomy.展开更多
Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) ...Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) were selected randomly. 52 patients with TCM syndrome of qi-yin deficiency were divided into Chinese and Western combination therapy group. 48 patients have no TCM syndrome of qi-yin deficiency, and were treated with standard western medicine. After treatment, Seattle Angina Questionnaire Evaluation, ECG, conventional and stress echocardiography (SE) index, NT-proBNP were compared between before and after treatment. Results: The differences of PL, TS, DP between before and after treatment by YFP were statistically significant展开更多
Viability of bifidobacteria in freeze-dried probiotic products at various temperatures during prolonged storage was assessed. Bifidobacterium longum and Bifidobacterium infantis were freeze-dried. The freeze-dried pre...Viability of bifidobacteria in freeze-dried probiotic products at various temperatures during prolonged storage was assessed. Bifidobacterium longum and Bifidobacterium infantis were freeze-dried. The freeze-dried preparations were stored at -18 , 4 , and 20 ℃. Cell counts were enumerated using BS agar at 37 ℃ for 48 h under anaerobic conditions at 0, 45 and 120 days. Storage at 20 ℃ showed the greatest decline in the viability of bifidobacteria, whereas that at -18 ℃ showed the least decrease.展开更多
[Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in com...[Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in combination with cefradine.[Methods]High performance liquid chromatography(HPLC)was used to detect the contents of baicalin,wogonin,chlorogenic acid and forsythin,the main components of Shuanghuanglian freeze-dried powder.HL-7702 cells were cultured with Shuanghuanglian freeze-dried powder and the main components of Shuanghuanglian freeze-dried powder alone or in combination with cefradine.Enzyme linked immunosorbent assay(ELISA)was used to detect the contents of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in the cell supernatant after culture,and HPLC was used to detect the expression level of adenosine diphosphate(ADP)and adenosine triphosphate(ATP);agarose gel electrophoresis was used to detect the expression of cyclooxygenase 2(COX-2)and heme oxygenase-1(HO-1)in HL-7702 cells.[Results]In Shuanghuanglian freeze-dried powder for injection,the content of baicalin was the highest,and the content of wogonin was the lowest.Compared with the control group,the expressions of AST and ALT in human hepatocytes(HL-7702)in high-dose baicalin group,forsythin group and wogonin group decreased(P<0.05,P<0.01),while the expression of ALT in chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)increased(P<0.05,P<0.01),and the expression of AST had no significant difference(P>0.05);the results in the low-dose group were similar to those in the high-dose group.Compared with the control group,ATP expression in chlorogenic acid group,chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)in the high-dose group decreased(P<0.05,P<0.01),and ADP expression was not significantly different(P>0.05);in the low-dose group,the expression of ATP and ADP increased in baicalin group(P<0.05),but decreased in wogonin group,baicalin+cefradine group(0.046 mg/mL)and wogonin group+cefradine group(0.046 mg/mL)(P<0.05,P<0.01).Compared with the control group,the expressions of COX-2 and HO-1 in HL-7702 cells in the cefradine group showed no significant difference(P>0.05).The expression of HO-1 and COX-2 in the different dose groups of Shuanghuanglian and the group combined with cefradine increased,and the difference was significant(P<0.05,P<0.01).[Conclusions]The components of Shuanghuanglian freeze-dried powder for injection had effects on hepatocytes,of which baicalin had a significant effect,and the effect of cefradine on hepatocytes was increased when used in combination with cefradine.展开更多
Membrane characteristics are determined by the fatty acids composition,which affects survival rates after freeze-drying.However,it is unknown which composition provides the greatest effect.In this study,we found that ...Membrane characteristics are determined by the fatty acids composition,which affects survival rates after freeze-drying.However,it is unknown which composition provides the greatest effect.In this study,we found that the addition of Tween 80 and Tween 20 significantly increased survival rates of Lactiplantibacillus plantarum,which reached a maximum of 93.1%.Conversely,Tween 60 caused a significant decrease.We further found that the difference between the effects of adding Tween 80 and Tween 60 was the change in oleic acid contents.To verify the role of oleic acid,we used CRISPR-Cas9 to knock-out the key synthesis gene cla-er.The survival rates of L.plantarum AR113Δcla-er declined to 5.48%.The addition of oleic acid restored the rates to those of wild type strains.Moreover,the membrane integrity and fl uidity of knockout strains markedly decreased.This is the fi rst confi rmation that Tween 80 or Tween 20 increases the survival rate by increasing the content of oleic acid in the cell membrane.These fi ndings also indicated that oleic acid in cell membranes has a substantial protective effect on L.plantarum during freeze-drying.展开更多
Various biological constraints including erratic and asynchronous flowering between male and female plants hinder successful hybrid development and genetic gains in greater yam breeding programs.Therefore,pollen stora...Various biological constraints including erratic and asynchronous flowering between male and female plants hinder successful hybrid development and genetic gains in greater yam breeding programs.Therefore,pollen storage has gained much attention to facilitate artificial pollinations and increase the genetic gains.This 4-year study aimed at developing a practical long-term pollen storage technique for the successful development of yam hybrids.Fresh pollens were collected from two Dioscorea alata males,then lyophilized(two lyophilization treatments were applied),followed by storage at room temperature(24℃–25℃)for 12 months.Moreover,the lyophilized and stored pollens were tested for viability by crossing with four female varieties.Our results showed that lyophilization is effective for achieving viable pollens after 12 months of storage.Treatment 1(48 h drying)showed higher pollen germination and fertility rates than Treatment 2(72 h drying).Although we observed a reduction in viability of lyophilized pollens after 12 months of storage,we generated hybrid seedlings with success rates from 12%to 21%compared to 21%–31%when using fresh pollens.Paternity testing based on molecular genotyping confirmed the hybrid status of the obtained seedlings,which grew well in a greenhouse.Lyophilization is a practical approach for a long-term storage of greater yam pollen samples.This protocol will positively impact yam breeding programs particularly in developing countries.展开更多
Aim: To determine the effect of two different extracts of red maca in male rats. Methods: Prostatic hyperplasia was induced in male rats with testosterone enanthate (TE). The study comprised six groups: one contr...Aim: To determine the effect of two different extracts of red maca in male rats. Methods: Prostatic hyperplasia was induced in male rats with testosterone enanthate (TE). The study comprised six groups: one control group (group 1), one group treated with TE (group 2), two groups treated with TE and aqueous extract of red maca (groups 3 and 4), one group treated with hydroalcoholic extract of red maca (group 5) and one group treated with finasteride (0.1 mg, group 6). Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates (0.02-0.08 mg) in red maca extracts was assessed. Results: Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion: The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.展开更多
In this work, we report a facile route for the synthesis of Li3V2(PO4)3/C cathode material via freezedrying and then calcination. The effect of calcination temperature on the electrochemical properties of the Li3V2(PO...In this work, we report a facile route for the synthesis of Li3V2(PO4)3/C cathode material via freezedrying and then calcination. The effect of calcination temperature on the electrochemical properties of the Li3V2(PO4)3/C is also investigated. When used as a lithium-ion battery cathode, the optimized Li3V2(PO4)3/C (LVP-800) through calcination at 800 ℃ exhibits a high initial charge and discharge capacity. The excellent electrochemical performance of LVP-800 is attributed to the good crystallinity and uniform morphology of the electrode material. In addition, the residual carbon can also improve the conductivity and buffer the volume expansion during the Li-ion extraction/reinsertion. Meanwhile, charge compensation also plays an important role in excellent electrochemical performance.展开更多
Freeze-drying,continuous passage and ultra-low temperature cryopreservation are often used to preserve pathogens.In this study,Vibrio anguillarum was rejuvenated by intramuscular infection as the initial strain.The di...Freeze-drying,continuous passage and ultra-low temperature cryopreservation are often used to preserve pathogens.In this study,Vibrio anguillarum was rejuvenated by intramuscular infection as the initial strain.The difference between cells preserved with different preservation methods and their initial strains were compared with physiological and biochemical methods and through antibiotics resistance analysis.The composition of protectants for freeze-drying V.anguillarum was optimized.We found that the optimal composition of protectants was 8% of trehalose,12% of skim milk,8.0% of lactose,2.0% of sodium citrate,12.0% of serum and 8.0% of mannitol.The indexes of lysine decarboxylase and urease changed after continuous passage.The urease reaction changed after freeze-drying and freeze-thawing,but the reaction can be restored to the initial after freeze-drying.Based on the antibiotics resistance analyses,the sensitivity of V.anguillarum to different drugs including rifampicin,erythrocin,furazolidone,ceftazidime,lomefloxacin,gentamycin,azithromycin,doxycycline,ampicillin,co-trimoxazole and cefoperazone changed after different treatments,and some of these changes can be restored to the original through activation culture.In sum,compared with cryopreservation and continuous passage,the freeze-drying is more sustainable for the long-term preservation of V.anguillarum,which showed a better effect in maintaining the original characteristics of pathogen.展开更多
AIM: To investigate the antifibrotic effect of the freeze-dried bilayered fibrin-binding amniotic membrane as a drug delivery system on glaucoma surgery in rabbit model. The aim of this study was to prepare a novel lo...AIM: To investigate the antifibrotic effect of the freeze-dried bilayered fibrin-binding amniotic membrane as a drug delivery system on glaucoma surgery in rabbit model. The aim of this study was to prepare a novel local delivery system for the sustained and controllable release of 5-Fu. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with 5-Fu loaded freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with 5-Fu) and the blank group (single trabeculectomy). HE staining, massion staining and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. The concentration of 5-Fu in rabbit aqueous humor was examined by high performance liquid chromatography (HPLC) 3 days after the surgery. RESULTS: Statistical differences were noted in intraocular pressure among groups on day 7, 14, 21 and 30 following surgery. Histology further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane yielded well wound healing and no scar formation and was beneficial for long term effect. CONCLUSION: HPLC showed a good slow-release effect with freeze-dried bilayered fibrin-binding amniotic membrane.展开更多
Lactic acid bacteria possess several interesting properties of great economic importance. Improvement and stabilization of these industrially important features are an active research area at the present time. The obj...Lactic acid bacteria possess several interesting properties of great economic importance. Improvement and stabilization of these industrially important features are an active research area at the present time. The objectives of this work are to study the effect of freezing and freeze-drying on the survival rate, autolytic activity and intracellular enzymatic activity of the main species of lactic acid bacteria used in the dairy industry. The article focused on several characteristics that were not well covered in the past. The obtained results revealed that both preservation methods have a significant effect on viability, autolytic activity and intracellular enzymatic activity. After six months of storage we found that frozen cultures exhibited higher survival rate, higher rate of intracellular enzymatic activity and lower rate of autolysis. The impact of conservation treatments was only strain specific in the case of survival rate. The results obtained lead to the selection of the best preservation method for the selected cultures based on survival rate, autolytic activity and intracellular enzymatic activity.展开更多
Objective: The Response Surface Methodology (RSM) is a commonly used system to optimize cell viability of probiotic strains when they are subjected to different preservation and storage processes. Methods and Results:...Objective: The Response Surface Methodology (RSM) is a commonly used system to optimize cell viability of probiotic strains when they are subjected to different preservation and storage processes. Methods and Results: To determine the optimal levels of incorporation of several cry oprotectants (skim milk, sucrose and trehalose) in the freeze-drying process of Lactobacillus plantarum, a range of experiments based on a Rotational Central Composite design (CCD) were conducted. The results were adjusted to a quadratic model, resulting in the presence of interaction between the different variables. Solving a regression equation, we obtained the optimum concentrations of cryoprotective agents: 24.06% milk powder, 6.22% sucrose, 5.63% trehalose. To visualize the interactions between the three variables involved in the study, Design Expert? software was used. Conclusions: The analysis reveals that while trehalose has a direct effect on the viability of L. plantarum, skim milk and sucrose exert quadratic effects. There are also interactions between cryoprotectants, which emphasize the synergies produced between milk and sucrose and between sucrose and trehalose, which allows maintaining the viability of L. plantarum. Significance and Impact of the Study: The addition of new oligosaccharides as trehalose in premixtures for functional feed can maintain the viability of L. plantarum during longer periods of time, ensuring the proper administration of probiotics to their destinations.展开更多
Nitrogen-rich Eu2+-doped Ca-α-SiAlON phosphors(Cam/2-xSi12-m-nAlm+nOnN16-n:xEu) were synthesized by a freeze-drying assisted combustion synthesis(CS) route. Fast-synthesized products with high purity and uniform part...Nitrogen-rich Eu2+-doped Ca-α-SiAlON phosphors(Cam/2-xSi12-m-nAlm+nOnN16-n:xEu) were synthesized by a freeze-drying assisted combustion synthesis(CS) route. Fast-synthesized products with high purity and uniform particle morphology were confirmed by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The analysis of lattice parameters by comparison with empirical equations showed that the as-prepared phosphors had low oxygen content. A series of samples were prepared according to the stoichiometry of Cam/2-0.08Si12-mAlmN16:0.08 Eu for further research. The influences of m value on the luminescence properties were investigated in detail. As m increased, a redshift phenomenon was observed in both the excitation and emission spectra. First-principle electronic structure calculations showed that the 3d energy level of Ca played an important role in the occurrence of the redshift phenomenon.展开更多
The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research h...The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research has shown that the accuracy of axon regeneration can be improved by a bionic structural implant. To this aim, iodine and freeze-drying high-resolution micro-computed tomography was performed to visualize the 3D topography of the New Zealand rabbit sciatic nerve (25 mm). A series of 1-, 2-, 3-, and 4-custom anatomy-based nerve conduits (CANCs) were fabricated based on the anatomical structure of the nerve fascicle. The match index, luminal surface, and mechanical properties of CANCs were evaluated before implanting in a 10-mm gap of the sciatic nerve. Recovery was evaluated by histomorphometric analyses, electrophysiological study, gastrocnemius muscle weight recovery ratio, and behavioral assessments at 12 and 24 weeks postoperatively. The accuracy of nerve regeneration was determined by changes in fluorescence-labeled profile number during simultaneous retrograde tracing. Our results showed that the optimal preprocessing condition for high-resolution micro-computed tomography visualization was treatment of the sciatic nerve with 40% Lugol’s solution for 3 days followed by lyophilization for 2 days. In vitro experiments demonstrated that the match index was highest in the 3-CANC group, followed by the 2-, 1-, and 4-CANC groups. The luminal surface was lowest in the 1-CANC group. Mechanical properties (transverse compressive and bending properties) were higher in the 3- and 4-CANC groups than in the 1-CANC group. In vivo experiments demonstrated that the recovery (morphology of regenerated fibers, compound muscle action potential, gastrocnemius muscle weight recovery ratio, pain-related autotomy behaviors, and range of motion) in the 3-CANC group was superior to the other CANC groups, and achieved the same therapeutic effect as the autograft. The simultaneous retrograde tracing results showed that the percentages of double-labeled profiles of the 2-, 3-, and 4-CANC groups were comparatively lower than that of the 1-CANC group, which indicates that regenerated nerve fascicles were less intermingled in the 2-, 3-, and 4-CANC groups. These findings demonstrate that the visualization of the rabbit sciatic nerve can be achieved by iodine and freeze-drying high-resolution micro-computed tomography, and that this method can be used to design CANCs with different channels that are based on the anatomical structure of the nerve. Compared with the 1-CANC, 3-CANC had a higher match index and luminal surface, and improved the accuracy of nerve regeneration by limiting the intermingling of the regenerated fascicles. All procedures were approved by the Animal Care and Use Committee, Xinjiang Medical University, China on April 4, 2017 (ethics approval No. IACUC20170315-02).展开更多
The increasing demand for oral macromolecule delivery encouraged the development of mi-croencapsulation technologies to protect such drugs against gastric and enzymatic degra-dation. However, microencapsulation often ...The increasing demand for oral macromolecule delivery encouraged the development of mi-croencapsulation technologies to protect such drugs against gastric and enzymatic degra-dation. However, microencapsulation often requires harsh conditions that may jeopardizetheir biological activity. Accordingly, many trials attempted to load macromolecules intoporous drug carriers to bypass any formulation induced instability. In this study, we pre-pared chitosan coated porous poly(d, l-lactide-co-glycolide)(PLGA) microparticles(MPs)loaded with insulin using a novel loading technique; double freeze-drying. The resultsshowed a significant increase in drug loading using only 5 mg/ml initial insulin concen-tration and conveyed a sustained drug release over uncoated MPs. Furthermore, SEM andconfocal microscopy confirmed pore blocking and insulin accumulation within the MPs re-spectively. The oral pharmacodynamic data on rats also proved the preservation of insulinbioactivity after formulation. Finally, the new coating technique proved to be efficient inproducing robust layer of chitosan with higher insulin loading while maintaining insulinactivity.展开更多
Porous Cu with macroscopically aligned channels was synthesized using a freeze-drying process.Camphene-based CuO slurry was prepared by milling at 60 °C with a small amount of dispersant.Freezing of a slurry was ...Porous Cu with macroscopically aligned channels was synthesized using a freeze-drying process.Camphene-based CuO slurry was prepared by milling at 60 °C with a small amount of dispersant.Freezing of a slurry was done at 25 °C while unidirectionally controlling the growth direction of the camphene.Pores were generated subsequently by sublimation of the camphene during drying.The green body was hydrogen-reduced at 300 °C for 30 min,and sintered in the furnace at 700 °C for 1 h under a hydrogen atmosphere.Microstructural observation reveals that all of the sintered samples are composed of only Cu phase and show macroscopic open pores with an average size of 100 μm which are aligned along its macroscopic growth direction.The internal wall of the macroscopic aligned pore shows relatively small pores due to the traces of the camphene left between the concentrated Cu particles on the internal wall.Increase in the porosity and pore size with increasing camphene content was explained by the change of the growth behavior of the camphene crystals.展开更多
Probiotics which can provide potential health benefits for consumers and prevent disease, is the most important research field for functional food in the future. It is the key point that how much the count of bacteria...Probiotics which can provide potential health benefits for consumers and prevent disease, is the most important research field for functional food in the future. It is the key point that how much the count of bacteria and how long it can preserve. Freeze-drying skill is one of the best preservation methods, but it's defect that damage to biological systems can be attributed to changes in the physical state of membrane lipids or/and changes in the structure of sensitive proteins and the decreased survival rate. This work used pretreatment methods-cold shock and hot shock to reduce the damage to bacteria during freeze-drying. Using unpretreated samples as control, aspects of cold shock or heat shock. The response of Enterococcous faecalis A31 was investigated during lag phase, the middle of exponential growth phase and the terminal of exponential growth phase. The results suggested that when cold shock, the shock protein concentration produced by treated sample within 2 h during the middle of exponential growth phase was higher than 4, 8, 24 h, The concentration of shock protein produced by treated sample at 10 ℃ was higher than 20℃, The concentration of sample protein at the middle of exponential growth phase was higher than that at the terminal of exponential growth phase. After one-month storage, the survival rate at 10℃ was better than 20 ℃ and 4 ℃comparatively. The survival rate at (6 h) 4 ℃/24 h (lag period) was higher than (10 h) 4 ℃/24 h (the middle of exponential growth phase), and the effect of 10℃/8 h shock treatments was best during the middle of exponential growth phase, when hot shock, The concentration of heat shock proteins produced was not obvious, and survival rate was higher at 45 ℃, 30 min than at 45 ℃, 60 min.展开更多
As an important process analysis tool,near infrared spectroscopy(NIRS)has been widely used in process monitoring.In the present work,the feasibility of NIRS for monitoring the moisture content of human coagulation fac...As an important process analysis tool,near infrared spectroscopy(NIRS)has been widely used in process monitoring.In the present work,the feasibility of NIRS for monitoring the moisture content of human coagulation factor VIII(FVIII)in freeze-drying process was investigated.A partial least squares regression(PLS-R)model for moisture content determination was built with 88 samples.Different pre-processing methods were explored,and the best method found was standard normal variate(SNV)transformation combined with 1st derivation with Savitzky–Golay(SG)15 point smoothing.Then,four different variable selection methods,including uninformative variable elimination(UVE),interval partial least squares regression(iPLS),competitive adaptive reweighted sampling(CARS)and manual method,were compared for eliminating irrelevant variables,and iPLS was chosen as the best variable selection method.The correlation coe±cient(R),correlation coe±cient of calibration set(Rcal),correlation coefficient of validation set(Rval),root mean square errors of cross-validation(RMSECV)and root mean square errors of prediction(RMSEP)of PLS model were 0.9284,0.9463,0.8890,0.4986% and 0.4514%,respectively.The results showed that the model for moisture content determination has a wide range,good linearity,accuracy and precision.The developed approach was demonstrated to be a potential for monitoring the moisture content of FVIII in freeze-drying process.展开更多
基金the Sichuan Huotai Pharmaceutical Co.,Ltd under Grant(20200601-1).
文摘Purpose Our purpose was to compare the difference between hot-air dried American ginseng(HDAG)(Panacis Quinquefolii Radix)and freeze-dried American ginseng(FDAG)(Panacis Quinquefolii Radix)and provide a better drying approach for improv-ing the quality of American ginseng(Panacis Quinquefolii Radix).Methods In our present study,we compared the appearance features of HDAG and FDAG using a CR-410 colorimeter and scanning electron microscopy.Furthermore,we qualitatively and quantitatively determined ginsenosides in HDAG and FDAG by using UPLC-Q Exactive Orbitrap-MS/MS and high-performance liquid chromatography.Results Our present results showed that compared to the hot-air drying method,freeze-drying(FD)has obvious advantages in not only good appearances but also higher bioactive constituents for drying the American ginseng(Panacis Quinquefolii Radix).Conclusion FD is beneficial for the retention of ginsenosides in American ginseng(Panacis Quinquefolii Radix)and also helpful for maintaining the bioactive effects of this functional food.
文摘Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, reduction of graphene oxide and loading of Ag/TiO2nanoparticles on graphene sheets were achieved. Investigation of chemical state of products showed that covering of Ag/TiO2surface with higher weight ratio of graphene resulting in that Ag metals in Ag/TiO2were oxidized to Ag2 O in nanocomposite structure after solvothermal process. Degree of photocatalytic activity enhancement strongly depends on the coverage of Ag/TiO2surface by porous graphene. The sample of 1 wt% porous graphene hybridized Ag/TiO2showed the highest photocatalytic activity, which is related to high migration efficiency of photoinduced of electrons and reduction of electron–hole recombination rate due to high electrical conductivity of graphene. Expanding of absorption to visible light region was ascribed to surface plasmon resonance effect of Ag metals and presence of graphene. Investigation of photocatalytic performance of formic acid as a dye-less organic pollutant showed that dye sensitization effect of Rh B molecules during evaluation of photocatalytic performance was negligible.
基金Natural Science Foundation of Hubei Province,China (No. 2008cda055)
文摘AIM: To investigate the antifibrotic effect of freeze-dried bilayered fibrin-binding amniotic membrane on trabeculectomy in a rabbit model. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with natural bilayered fibrin-binding amniotic membrane) and the blank group (single trabeculectomy). Clinical observation, hematoxylin-eosin staining, Massion staining, real-time PCR and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. RESULTS: Statistical differences were noted in survival. analysis and intraocular pressure(IOP) among groups on days 7, 14, 21 and 30 following surgery. Histology, immunohistochemistry and real-time PCR further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane resulted in good wound healing and no scar formation. CONCLUSION: Self-made freeze-dried bilayered fibrin-binding amniotic membrane may inhibit the formation of scarring in glaucoma after trabeculectomy.
文摘Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) were selected randomly. 52 patients with TCM syndrome of qi-yin deficiency were divided into Chinese and Western combination therapy group. 48 patients have no TCM syndrome of qi-yin deficiency, and were treated with standard western medicine. After treatment, Seattle Angina Questionnaire Evaluation, ECG, conventional and stress echocardiography (SE) index, NT-proBNP were compared between before and after treatment. Results: The differences of PL, TS, DP between before and after treatment by YFP were statistically significant
文摘Viability of bifidobacteria in freeze-dried probiotic products at various temperatures during prolonged storage was assessed. Bifidobacterium longum and Bifidobacterium infantis were freeze-dried. The freeze-dried preparations were stored at -18 , 4 , and 20 ℃. Cell counts were enumerated using BS agar at 37 ℃ for 48 h under anaerobic conditions at 0, 45 and 120 days. Storage at 20 ℃ showed the greatest decline in the viability of bifidobacteria, whereas that at -18 ℃ showed the least decrease.
基金Guangxi Natural Science(2018GXNSFBA-050051)Doctor Initiation Fund Project of Guangxi University of Traditional Chinese Medicine(2020BS011)。
文摘[Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in combination with cefradine.[Methods]High performance liquid chromatography(HPLC)was used to detect the contents of baicalin,wogonin,chlorogenic acid and forsythin,the main components of Shuanghuanglian freeze-dried powder.HL-7702 cells were cultured with Shuanghuanglian freeze-dried powder and the main components of Shuanghuanglian freeze-dried powder alone or in combination with cefradine.Enzyme linked immunosorbent assay(ELISA)was used to detect the contents of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in the cell supernatant after culture,and HPLC was used to detect the expression level of adenosine diphosphate(ADP)and adenosine triphosphate(ATP);agarose gel electrophoresis was used to detect the expression of cyclooxygenase 2(COX-2)and heme oxygenase-1(HO-1)in HL-7702 cells.[Results]In Shuanghuanglian freeze-dried powder for injection,the content of baicalin was the highest,and the content of wogonin was the lowest.Compared with the control group,the expressions of AST and ALT in human hepatocytes(HL-7702)in high-dose baicalin group,forsythin group and wogonin group decreased(P<0.05,P<0.01),while the expression of ALT in chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)increased(P<0.05,P<0.01),and the expression of AST had no significant difference(P>0.05);the results in the low-dose group were similar to those in the high-dose group.Compared with the control group,ATP expression in chlorogenic acid group,chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)in the high-dose group decreased(P<0.05,P<0.01),and ADP expression was not significantly different(P>0.05);in the low-dose group,the expression of ATP and ADP increased in baicalin group(P<0.05),but decreased in wogonin group,baicalin+cefradine group(0.046 mg/mL)and wogonin group+cefradine group(0.046 mg/mL)(P<0.05,P<0.01).Compared with the control group,the expressions of COX-2 and HO-1 in HL-7702 cells in the cefradine group showed no significant difference(P>0.05).The expression of HO-1 and COX-2 in the different dose groups of Shuanghuanglian and the group combined with cefradine increased,and the difference was significant(P<0.05,P<0.01).[Conclusions]The components of Shuanghuanglian freeze-dried powder for injection had effects on hepatocytes,of which baicalin had a significant effect,and the effect of cefradine on hepatocytes was increased when used in combination with cefradine.
基金funded by National Natural Science Foundation of China(32172186)National Science Foundation for Distinguished Young Scholars of China(32025029)+1 种基金Shanghai Education committee scientific research innovation projects,China(2101070007800120)Shanghai Engineering Research Center of Food Microbiology(19DZ2281100).
文摘Membrane characteristics are determined by the fatty acids composition,which affects survival rates after freeze-drying.However,it is unknown which composition provides the greatest effect.In this study,we found that the addition of Tween 80 and Tween 20 significantly increased survival rates of Lactiplantibacillus plantarum,which reached a maximum of 93.1%.Conversely,Tween 60 caused a significant decrease.We further found that the difference between the effects of adding Tween 80 and Tween 60 was the change in oleic acid contents.To verify the role of oleic acid,we used CRISPR-Cas9 to knock-out the key synthesis gene cla-er.The survival rates of L.plantarum AR113Δcla-er declined to 5.48%.The addition of oleic acid restored the rates to those of wild type strains.Moreover,the membrane integrity and fl uidity of knockout strains markedly decreased.This is the fi rst confi rmation that Tween 80 or Tween 20 increases the survival rate by increasing the content of oleic acid in the cell membrane.These fi ndings also indicated that oleic acid in cell membranes has a substantial protective effect on L.plantarum during freeze-drying.
基金financially supported by the AfricaYam Project(Grant OPP1052998-Bill and Melinda Gates Foundation).
文摘Various biological constraints including erratic and asynchronous flowering between male and female plants hinder successful hybrid development and genetic gains in greater yam breeding programs.Therefore,pollen storage has gained much attention to facilitate artificial pollinations and increase the genetic gains.This 4-year study aimed at developing a practical long-term pollen storage technique for the successful development of yam hybrids.Fresh pollens were collected from two Dioscorea alata males,then lyophilized(two lyophilization treatments were applied),followed by storage at room temperature(24℃–25℃)for 12 months.Moreover,the lyophilized and stored pollens were tested for viability by crossing with four female varieties.Our results showed that lyophilization is effective for achieving viable pollens after 12 months of storage.Treatment 1(48 h drying)showed higher pollen germination and fertility rates than Treatment 2(72 h drying).Although we observed a reduction in viability of lyophilized pollens after 12 months of storage,we generated hybrid seedlings with success rates from 12%to 21%compared to 21%–31%when using fresh pollens.Paternity testing based on molecular genotyping confirmed the hybrid status of the obtained seedlings,which grew well in a greenhouse.Lyophilization is a practical approach for a long-term storage of greater yam pollen samples.This protocol will positively impact yam breeding programs particularly in developing countries.
文摘Aim: To determine the effect of two different extracts of red maca in male rats. Methods: Prostatic hyperplasia was induced in male rats with testosterone enanthate (TE). The study comprised six groups: one control group (group 1), one group treated with TE (group 2), two groups treated with TE and aqueous extract of red maca (groups 3 and 4), one group treated with hydroalcoholic extract of red maca (group 5) and one group treated with finasteride (0.1 mg, group 6). Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates (0.02-0.08 mg) in red maca extracts was assessed. Results: Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion: The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.
基金supported by the National Key R&D Program of China(No.2016YFB0100500)
文摘In this work, we report a facile route for the synthesis of Li3V2(PO4)3/C cathode material via freezedrying and then calcination. The effect of calcination temperature on the electrochemical properties of the Li3V2(PO4)3/C is also investigated. When used as a lithium-ion battery cathode, the optimized Li3V2(PO4)3/C (LVP-800) through calcination at 800 ℃ exhibits a high initial charge and discharge capacity. The excellent electrochemical performance of LVP-800 is attributed to the good crystallinity and uniform morphology of the electrode material. In addition, the residual carbon can also improve the conductivity and buffer the volume expansion during the Li-ion extraction/reinsertion. Meanwhile, charge compensation also plays an important role in excellent electrochemical performance.
基金funded by the Key Projects of Science and Technology Innovation of Shandong Province (No. 2018YFJH0703)the Central Public-Interest Scientific Institution Basal Research Fund+1 种基金Yellow Sea Fisheries Research Institutes, CAFS (No. 20603022017004)the Projects of International Exchange and Cooperation in Agriculture, Ministry of Agriculture and Rural Affairs of China-Science, Technology and Innovation Cooperation in Aquaculture with Tropical Countries
文摘Freeze-drying,continuous passage and ultra-low temperature cryopreservation are often used to preserve pathogens.In this study,Vibrio anguillarum was rejuvenated by intramuscular infection as the initial strain.The difference between cells preserved with different preservation methods and their initial strains were compared with physiological and biochemical methods and through antibiotics resistance analysis.The composition of protectants for freeze-drying V.anguillarum was optimized.We found that the optimal composition of protectants was 8% of trehalose,12% of skim milk,8.0% of lactose,2.0% of sodium citrate,12.0% of serum and 8.0% of mannitol.The indexes of lysine decarboxylase and urease changed after continuous passage.The urease reaction changed after freeze-drying and freeze-thawing,but the reaction can be restored to the initial after freeze-drying.Based on the antibiotics resistance analyses,the sensitivity of V.anguillarum to different drugs including rifampicin,erythrocin,furazolidone,ceftazidime,lomefloxacin,gentamycin,azithromycin,doxycycline,ampicillin,co-trimoxazole and cefoperazone changed after different treatments,and some of these changes can be restored to the original through activation culture.In sum,compared with cryopreservation and continuous passage,the freeze-drying is more sustainable for the long-term preservation of V.anguillarum,which showed a better effect in maintaining the original characteristics of pathogen.
基金Natural Science Foundation of Hubei Province, China (No.2008cda055)
文摘AIM: To investigate the antifibrotic effect of the freeze-dried bilayered fibrin-binding amniotic membrane as a drug delivery system on glaucoma surgery in rabbit model. The aim of this study was to prepare a novel local delivery system for the sustained and controllable release of 5-Fu. METHODS: Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with 5-Fu loaded freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with 5-Fu) and the blank group (single trabeculectomy). HE staining, massion staining and immunohistochemistry for alpha -SMA were performed on days 7, 14, 21 and 30 following surgery. The concentration of 5-Fu in rabbit aqueous humor was examined by high performance liquid chromatography (HPLC) 3 days after the surgery. RESULTS: Statistical differences were noted in intraocular pressure among groups on day 7, 14, 21 and 30 following surgery. Histology further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane yielded well wound healing and no scar formation and was beneficial for long term effect. CONCLUSION: HPLC showed a good slow-release effect with freeze-dried bilayered fibrin-binding amniotic membrane.
文摘Lactic acid bacteria possess several interesting properties of great economic importance. Improvement and stabilization of these industrially important features are an active research area at the present time. The objectives of this work are to study the effect of freezing and freeze-drying on the survival rate, autolytic activity and intracellular enzymatic activity of the main species of lactic acid bacteria used in the dairy industry. The article focused on several characteristics that were not well covered in the past. The obtained results revealed that both preservation methods have a significant effect on viability, autolytic activity and intracellular enzymatic activity. After six months of storage we found that frozen cultures exhibited higher survival rate, higher rate of intracellular enzymatic activity and lower rate of autolysis. The impact of conservation treatments was only strain specific in the case of survival rate. The results obtained lead to the selection of the best preservation method for the selected cultures based on survival rate, autolytic activity and intracellular enzymatic activity.
文摘Objective: The Response Surface Methodology (RSM) is a commonly used system to optimize cell viability of probiotic strains when they are subjected to different preservation and storage processes. Methods and Results: To determine the optimal levels of incorporation of several cry oprotectants (skim milk, sucrose and trehalose) in the freeze-drying process of Lactobacillus plantarum, a range of experiments based on a Rotational Central Composite design (CCD) were conducted. The results were adjusted to a quadratic model, resulting in the presence of interaction between the different variables. Solving a regression equation, we obtained the optimum concentrations of cryoprotective agents: 24.06% milk powder, 6.22% sucrose, 5.63% trehalose. To visualize the interactions between the three variables involved in the study, Design Expert? software was used. Conclusions: The analysis reveals that while trehalose has a direct effect on the viability of L. plantarum, skim milk and sucrose exert quadratic effects. There are also interactions between cryoprotectants, which emphasize the synergies produced between milk and sucrose and between sucrose and trehalose, which allows maintaining the viability of L. plantarum. Significance and Impact of the Study: The addition of new oligosaccharides as trehalose in premixtures for functional feed can maintain the viability of L. plantarum during longer periods of time, ensuring the proper administration of probiotics to their destinations.
基金This work was financially supported by the Chinese Academy of Sciences(CAS)Interdisciplinary Innovation Teamthe Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China(No.19XNLG13).
文摘Nitrogen-rich Eu2+-doped Ca-α-SiAlON phosphors(Cam/2-xSi12-m-nAlm+nOnN16-n:xEu) were synthesized by a freeze-drying assisted combustion synthesis(CS) route. Fast-synthesized products with high purity and uniform particle morphology were confirmed by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The analysis of lattice parameters by comparison with empirical equations showed that the as-prepared phosphors had low oxygen content. A series of samples were prepared according to the stoichiometry of Cam/2-0.08Si12-mAlmN16:0.08 Eu for further research. The influences of m value on the luminescence properties were investigated in detail. As m increased, a redshift phenomenon was observed in both the excitation and emission spectra. First-principle electronic structure calculations showed that the 3d energy level of Ca played an important role in the occurrence of the redshift phenomenon.
基金supported by the National Natural Science Foundation of China,No.81360270,81560357(both to AY),and 31670986(to QTZ)the Key Laboratory of Hand Reconstruction,Ministry of Health,China+1 种基金the Shanghai Key Laboratory of Peripheral Nerve and Microsurgery of China,No.17DZ2270500(to AY)the Science and Technology Project of Guangdong Province of China,No.2014B020227001,2017A050501017(both to QTZ)
文摘The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research has shown that the accuracy of axon regeneration can be improved by a bionic structural implant. To this aim, iodine and freeze-drying high-resolution micro-computed tomography was performed to visualize the 3D topography of the New Zealand rabbit sciatic nerve (25 mm). A series of 1-, 2-, 3-, and 4-custom anatomy-based nerve conduits (CANCs) were fabricated based on the anatomical structure of the nerve fascicle. The match index, luminal surface, and mechanical properties of CANCs were evaluated before implanting in a 10-mm gap of the sciatic nerve. Recovery was evaluated by histomorphometric analyses, electrophysiological study, gastrocnemius muscle weight recovery ratio, and behavioral assessments at 12 and 24 weeks postoperatively. The accuracy of nerve regeneration was determined by changes in fluorescence-labeled profile number during simultaneous retrograde tracing. Our results showed that the optimal preprocessing condition for high-resolution micro-computed tomography visualization was treatment of the sciatic nerve with 40% Lugol’s solution for 3 days followed by lyophilization for 2 days. In vitro experiments demonstrated that the match index was highest in the 3-CANC group, followed by the 2-, 1-, and 4-CANC groups. The luminal surface was lowest in the 1-CANC group. Mechanical properties (transverse compressive and bending properties) were higher in the 3- and 4-CANC groups than in the 1-CANC group. In vivo experiments demonstrated that the recovery (morphology of regenerated fibers, compound muscle action potential, gastrocnemius muscle weight recovery ratio, pain-related autotomy behaviors, and range of motion) in the 3-CANC group was superior to the other CANC groups, and achieved the same therapeutic effect as the autograft. The simultaneous retrograde tracing results showed that the percentages of double-labeled profiles of the 2-, 3-, and 4-CANC groups were comparatively lower than that of the 1-CANC group, which indicates that regenerated nerve fascicles were less intermingled in the 2-, 3-, and 4-CANC groups. These findings demonstrate that the visualization of the rabbit sciatic nerve can be achieved by iodine and freeze-drying high-resolution micro-computed tomography, and that this method can be used to design CANCs with different channels that are based on the anatomical structure of the nerve. Compared with the 1-CANC, 3-CANC had a higher match index and luminal surface, and improved the accuracy of nerve regeneration by limiting the intermingling of the regenerated fascicles. All procedures were approved by the Animal Care and Use Committee, Xinjiang Medical University, China on April 4, 2017 (ethics approval No. IACUC20170315-02).
文摘The increasing demand for oral macromolecule delivery encouraged the development of mi-croencapsulation technologies to protect such drugs against gastric and enzymatic degra-dation. However, microencapsulation often requires harsh conditions that may jeopardizetheir biological activity. Accordingly, many trials attempted to load macromolecules intoporous drug carriers to bypass any formulation induced instability. In this study, we pre-pared chitosan coated porous poly(d, l-lactide-co-glycolide)(PLGA) microparticles(MPs)loaded with insulin using a novel loading technique; double freeze-drying. The resultsshowed a significant increase in drug loading using only 5 mg/ml initial insulin concen-tration and conveyed a sustained drug release over uncoated MPs. Furthermore, SEM andconfocal microscopy confirmed pore blocking and insulin accumulation within the MPs re-spectively. The oral pharmacodynamic data on rats also proved the preservation of insulinbioactivity after formulation. Finally, the new coating technique proved to be efficient inproducing robust layer of chitosan with higher insulin loading while maintaining insulinactivity.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(grant number2009-0089508)
文摘Porous Cu with macroscopically aligned channels was synthesized using a freeze-drying process.Camphene-based CuO slurry was prepared by milling at 60 °C with a small amount of dispersant.Freezing of a slurry was done at 25 °C while unidirectionally controlling the growth direction of the camphene.Pores were generated subsequently by sublimation of the camphene during drying.The green body was hydrogen-reduced at 300 °C for 30 min,and sintered in the furnace at 700 °C for 1 h under a hydrogen atmosphere.Microstructural observation reveals that all of the sintered samples are composed of only Cu phase and show macroscopic open pores with an average size of 100 μm which are aligned along its macroscopic growth direction.The internal wall of the macroscopic aligned pore shows relatively small pores due to the traces of the camphene left between the concentrated Cu particles on the internal wall.Increase in the porosity and pore size with increasing camphene content was explained by the change of the growth behavior of the camphene crystals.
基金Supported by National Agricultural Translation Fund (02EFN212301073)
文摘Probiotics which can provide potential health benefits for consumers and prevent disease, is the most important research field for functional food in the future. It is the key point that how much the count of bacteria and how long it can preserve. Freeze-drying skill is one of the best preservation methods, but it's defect that damage to biological systems can be attributed to changes in the physical state of membrane lipids or/and changes in the structure of sensitive proteins and the decreased survival rate. This work used pretreatment methods-cold shock and hot shock to reduce the damage to bacteria during freeze-drying. Using unpretreated samples as control, aspects of cold shock or heat shock. The response of Enterococcous faecalis A31 was investigated during lag phase, the middle of exponential growth phase and the terminal of exponential growth phase. The results suggested that when cold shock, the shock protein concentration produced by treated sample within 2 h during the middle of exponential growth phase was higher than 4, 8, 24 h, The concentration of shock protein produced by treated sample at 10 ℃ was higher than 20℃, The concentration of sample protein at the middle of exponential growth phase was higher than that at the terminal of exponential growth phase. After one-month storage, the survival rate at 10℃ was better than 20 ℃ and 4 ℃comparatively. The survival rate at (6 h) 4 ℃/24 h (lag period) was higher than (10 h) 4 ℃/24 h (the middle of exponential growth phase), and the effect of 10℃/8 h shock treatments was best during the middle of exponential growth phase, when hot shock, The concentration of heat shock proteins produced was not obvious, and survival rate was higher at 45 ℃, 30 min than at 45 ℃, 60 min.
基金We are grateful for the financial support of the Major Special Project of National Science and Technology (No.2014ZX09508003).
文摘As an important process analysis tool,near infrared spectroscopy(NIRS)has been widely used in process monitoring.In the present work,the feasibility of NIRS for monitoring the moisture content of human coagulation factor VIII(FVIII)in freeze-drying process was investigated.A partial least squares regression(PLS-R)model for moisture content determination was built with 88 samples.Different pre-processing methods were explored,and the best method found was standard normal variate(SNV)transformation combined with 1st derivation with Savitzky–Golay(SG)15 point smoothing.Then,four different variable selection methods,including uninformative variable elimination(UVE),interval partial least squares regression(iPLS),competitive adaptive reweighted sampling(CARS)and manual method,were compared for eliminating irrelevant variables,and iPLS was chosen as the best variable selection method.The correlation coe±cient(R),correlation coe±cient of calibration set(Rcal),correlation coefficient of validation set(Rval),root mean square errors of cross-validation(RMSECV)and root mean square errors of prediction(RMSEP)of PLS model were 0.9284,0.9463,0.8890,0.4986% and 0.4514%,respectively.The results showed that the model for moisture content determination has a wide range,good linearity,accuracy and precision.The developed approach was demonstrated to be a potential for monitoring the moisture content of FVIII in freeze-drying process.