The protective effect of oleic acid on Lactiplantibacillus plantarum during freeze-drying

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.

热风干燥和冷冻干燥对西洋参外观、显微特征和人参皂苷含量影响的比较研究

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.

Ag/TiO_2/freeze-dried graphene nanocomposite as a high performance photocatalyst under visible light irradiation

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.

Study of self-made freeze-dried bilayered fibrin-binding amniotic membrane in ocular trabeculectomy in rabbits

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.

Facile synthesis of Li3V2（PO4）3/C cathode material for lithium-ion battery via freeze-drying

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.

Microstructure of porous Cu fabricated by freeze-drying process of CuO/camphene slurry

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.

Luminescence properties of nitrogen-rich Ca-SiAlON:Eu2+ phosphors prepared by freeze-drying assisted combustion synthesis

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.

Application of near infrared spectroscopy in monitoring the moisture content in freeze-drying process of human coagulation factor VIII

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.

Efficacy of Yiqi Fumai (Freeze-Dried Powder) on Ischemic Diastolic Heart Failure

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

Viability of Two Freeze-dried Strains of Bifidobacterium Preparations at Various Temperatures during Prolonged Storage

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.

Growth and Freeze-Drying Optimization of Bifidobacterium crudilactis

Bifidobacterium crudilactis FR62/b/3 belongs to a new population of bifidobacteria isolated from raw milk and raw milk cheese. The objective of this work was to study the large scale culture of the strain and its stability in a dry formulation. Growth rate of Bifidobacterium crudilactis FR62/b/3 was optimal at a pH of 5.0 and a temperature of 37°C. At a temperature growth of 33°C and a pH of 5.0, the stationary phase was reached after 22 h, the viable cell number and the mean dry biomass concentration were respectively of 8.3 × 109 CFU/mL and of 2.1 g/L. Resistance of Bifidobacterium crudilactis FR62/b/3 to freeze-drying and effect of a variety of cryoprotectants to maintain the viability were also evaluated. Sorbitol was the most suitable cryoprotectant for freeze-drying as well as storage whereas sucrose and monosodium glutamate were only efficient during storage.

Chicken Embryo Inhibition Test of Recombinant Freeze-drying Chicken Interferon against Newcastle Disease Virus( NDV) F_(48)E_(10)

The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying chicken interferon via allaotoic sack, while 10-day-old chicken embryos were inoculated with NDV F48E10, and in vivo protective efficacy of interferon on chichen embryos was studied. The results showed that the recombinant freeze-drying chicken interferon at the dose of 1.28 mg/embryo reached the protection ratio of 90% on chicken embryo infected by F48E10.

Component Analysis of Shuanghuanglian Freeze-dried Powder and Its Effects on Human Hepatocyte Function when Combined with Cefradine

[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.

First Report of a Successful Development of Yam Hybrids(Dioscorea alata L.)from Lyophilized and Long-Term Stored Pollens

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.

Enzymatic preparation of mono-and diacylglycerols:A review

Monoacylglycerols(MAGs) and diacylglycerols(DAGs) are partial glycerides widely used in food industry. They are safe and non-toxic food emulsifiers, especially for MAGs. MAGs account for approximately 75% of the total emulsifiers in food industry worldwide. DAGs are recognized as functional cooking oils, they can suppress body fat accumulation and postprandial serum triacylglycerols(TAGs) level. The traditional production of MAGs and DAGs is based on the chemical method, which requires high reaction temperature usually up to 200–260 ℃. Such high temperature is not suitable for oil containing heat sensitive polyunsaturated fatty acids. Enzymatic approach has been received increasing attentions. Enzymatic production of partial glycerides to replace chemical processes has been in industry, particularly for DAGs production as the products have been claimed as a functional and nutritional oil. Enzyme technology for the processing of oils and fats has been moved to industry step by step and case by case during the last 20 years. More and more applications are particularly moving into bulky oils and fats processing. At the same time, the cost of enzymes as a commercial product is reducing steadily. This review summarized the recent 15 years advances on the the enzymatic preparation of MAGs and DAGs. The critical process parameters under different reaction routes were presented and emphasized. The reaction media not only increased the homogeneity of the reaction system, but also shifted the reaction equilibrium towards the target product generation, and this part was stated in detail. In addition, the patent evaluation was included, and the application of MAGs and DAGs was covered.

Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia

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.

Effects of Different Preservation Methods on Physicochemical Property of Marine Pathogen Vibrio anguillarum

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.

Influence of Freezing and Freeze Drying on Intracellular Enzymatic Activity and Autolytic Properties of Some Lactic Acid Bacterial Strains

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.

Homemade lyophilized cross linking amniotic sustained-release drug membrane with anti-scarring role after filtering surgery in rabbit eyes

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.

Enhacement of the Viability of <i>Lactobacillus</i><i>plantarum</i>during the Preservation and Storage Process Based on the Response Surface Methodology

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.