Gelatins extracted from two edible insects Aspongubus viduatus （melon bug） and Agonoscelis pubescens （sorghum bug） were studied. The two insects showed 27.0 and 28.2% crude protein, respectively. Extraction of gel...Gelatins extracted from two edible insects Aspongubus viduatus （melon bug） and Agonoscelis pubescens （sorghum bug） were studied. The two insects showed 27.0 and 28.2% crude protein, respectively. Extraction of gelatin using hot water gave high yield followed by mild acid and distilled water extraction, respectively. SDS-PAGE pattern showed low molecular weight chains, and the two gelatins contained protein with molecular weight of 40 kDa as main component. The differential scanning calorimetry thermograms results confirm no difference between extraction methods concerning the extracted gelatin quality. FTIR spectra of melon and sorghum bug gelatins were similar and the absorption bands were situated in more than 6 bands in melon bug gelatin and only 6 bands in sorghum bug gelatin. Amide II bands of gelatins from both melon and sorghum bug appeared at around 1554 cm^-1, while Amide I bands （1734-1632 cmt） appeared only in melon bug method 2 （MB2） and melon bug method3 （MB3）. Microstructures of the insect gelatin examined with the scanning electron microscope showed that melon bug exhibited the finest gelatin network with very small voids. Melon bug gelatin showed finer structure with smaller protein strands and voids than sorghum bug gelatin.展开更多
Propolis collected by stingless bees from various types of plants has been used as an antimicrobial agent in several previous studies. We assessed the effect of propolis produced by a stingless bee, Trigona apicalis, ...Propolis collected by stingless bees from various types of plants has been used as an antimicrobial agent in several previous studies. We assessed the effect of propolis produced by a stingless bee, Trigona apicalis, on Apis florea experimentally infected with Nosema ceranae, a parasite of honeybees. For parasite inoculation each Nosema free-bee was fed 2μL of 50% （w/v） sucrose solution containing N. ceranae spores at 40,000 spores/bee and 0 as a negative control （CO）. Treated bees were provided with 0%, 10%, 20% and 50% propolis （w/v） in water, defined as 0P, 10P, 20P and 50P, respectively. We assessed the effects of propolis 14 days post inoculation. All propolis-treated bees had significantly higher survival than untreated bees. However, survival of Nosema-inoculated bees was lower than that of control bees. Bees treated with the highest propolis concentration （50P） had the highest survival ratio. No control bees became infected over the course of the study. However, N. ceranae infection rates of bees treated with 0P, 10P, 20P and 50P were 75 ± 1.4%, 72 ± 5.6%, 69± 4.2% and 47± 1.4%, respectively. In addition, propolis-treated bees had hypopharyngeal gland protein content that was significantly higher than 0P and CO bees. Overall, propolis treatment significantly reduced N. ceranae infection rate and bee mortality and was associated with increased hypopharyngeal gland protein concentration.展开更多
OBJECTIVE: To study the role of the synthesis and degradation of collagen at the transcription level during liver fibrogenesis due to schistosomiasis japonica in rabbits. METHODS: New Zealand rabbits challenged by cer...OBJECTIVE: To study the role of the synthesis and degradation of collagen at the transcription level during liver fibrogenesis due to schistosomiasis japonica in rabbits. METHODS: New Zealand rabbits challenged by cercariae of Schistosoma japonicum (S. japonicum) were served as animal models for liver fibrosis. Liver specimens were collected through operations at 4, 6, 8, 10, 12, 16, 20, 24 and 28 wks after challenge. Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels of liver tissue were detected by RT-PCR + Dot blot. The size of egg granulomas and the degree of liver fibrosis were measured by histopathological examinations. RESULTS: Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased simultaneously in the early stage after challenge. Most of them reached their peak at 10 weeks, and compared with normal controls, type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased by 12.0-, 11.0-, 6.6-, 10.0- and 11.0-fold, respectively, coinciding with the change of egg granulomas, i.e., the change in the inflammatory process. Then both collagen and collagenase mRNA levels decreased. Type I, III and IV collagen mRNA levels declined to 2-fold to 3-fold as compared with normal controls (P 0.05) at 28 wks. This study shows that the synthesis and degradation of collagen keep a dynamic balance at the early stage of schistosomiasis japonica challenge, while at the later stages the quantity of collagen synthesis was higher than that of collagen degradation. CONCLUSIONS: It was confirmed at transcription level that when the quantity of collagen synthesis was higher than that of collagen degradation liver fibrogenesis may be resulted in.展开更多
A metal-ligand coordinated surfactant system formed by calcium dodecylsulfate(Ca(DS)2)/tetradecyldimethylamine oxide (C14DMAO)/H2O was studied in terms of surface tension,conductivity,negative-staining TEM,phase behav...A metal-ligand coordinated surfactant system formed by calcium dodecylsulfate(Ca(DS)2)/tetradecyldimethylamine oxide (C14DMAO)/H2O was studied in terms of surface tension,conductivity,negative-staining TEM,phase behavior and rheological operation.In C14DMAO solution,when Ca(DS)2 is added,metal-ligand complexes form between the Ca 2+and N→O group of C14DMAO.Under this metal-ligand driving force,different phases can be obtained at different concentrations and different ratios of Ca(DS)2 and C14DMAO.At the fixed C14DMAO concentration,L1-phase consisting of spherical micelles forms at first.With the addition of Ca(DS)2,the spherical micelles elongate to be wormlike micelles and then after an L1/L-two phase region,the birefringent vesicle-phase(Lv-phase)region is observed.When Ca(DS)2 concentration continues to increase,a gel-phase region is found after the Lv-phase region and then precipitates of undissolved Ca(DS)2 appear.The transition between different phases is affected by temperature remarkably.The wormlike micellar solutions and vesicle solutions were checked by rheological measurements and showed apparent viscoelasticity at high surfactant concentrations.展开更多
文摘Gelatins extracted from two edible insects Aspongubus viduatus （melon bug） and Agonoscelis pubescens （sorghum bug） were studied. The two insects showed 27.0 and 28.2% crude protein, respectively. Extraction of gelatin using hot water gave high yield followed by mild acid and distilled water extraction, respectively. SDS-PAGE pattern showed low molecular weight chains, and the two gelatins contained protein with molecular weight of 40 kDa as main component. The differential scanning calorimetry thermograms results confirm no difference between extraction methods concerning the extracted gelatin quality. FTIR spectra of melon and sorghum bug gelatins were similar and the absorption bands were situated in more than 6 bands in melon bug gelatin and only 6 bands in sorghum bug gelatin. Amide II bands of gelatins from both melon and sorghum bug appeared at around 1554 cm^-1, while Amide I bands （1734-1632 cmt） appeared only in melon bug method 2 （MB2） and melon bug method3 （MB3）. Microstructures of the insect gelatin examined with the scanning electron microscope showed that melon bug exhibited the finest gelatin network with very small voids. Melon bug gelatin showed finer structure with smaller protein strands and voids than sorghum bug gelatin.
文摘Propolis collected by stingless bees from various types of plants has been used as an antimicrobial agent in several previous studies. We assessed the effect of propolis produced by a stingless bee, Trigona apicalis, on Apis florea experimentally infected with Nosema ceranae, a parasite of honeybees. For parasite inoculation each Nosema free-bee was fed 2μL of 50% （w/v） sucrose solution containing N. ceranae spores at 40,000 spores/bee and 0 as a negative control （CO）. Treated bees were provided with 0%, 10%, 20% and 50% propolis （w/v） in water, defined as 0P, 10P, 20P and 50P, respectively. We assessed the effects of propolis 14 days post inoculation. All propolis-treated bees had significantly higher survival than untreated bees. However, survival of Nosema-inoculated bees was lower than that of control bees. Bees treated with the highest propolis concentration （50P） had the highest survival ratio. No control bees became infected over the course of the study. However, N. ceranae infection rates of bees treated with 0P, 10P, 20P and 50P were 75 ± 1.4%, 72 ± 5.6%, 69± 4.2% and 47± 1.4%, respectively. In addition, propolis-treated bees had hypopharyngeal gland protein content that was significantly higher than 0P and CO bees. Overall, propolis treatment significantly reduced N. ceranae infection rate and bee mortality and was associated with increased hypopharyngeal gland protein concentration.
文摘OBJECTIVE: To study the role of the synthesis and degradation of collagen at the transcription level during liver fibrogenesis due to schistosomiasis japonica in rabbits. METHODS: New Zealand rabbits challenged by cercariae of Schistosoma japonicum (S. japonicum) were served as animal models for liver fibrosis. Liver specimens were collected through operations at 4, 6, 8, 10, 12, 16, 20, 24 and 28 wks after challenge. Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels of liver tissue were detected by RT-PCR + Dot blot. The size of egg granulomas and the degree of liver fibrosis were measured by histopathological examinations. RESULTS: Type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased simultaneously in the early stage after challenge. Most of them reached their peak at 10 weeks, and compared with normal controls, type I collagen, type III collagen, type IV collagen, MMP-1 and MMP-9 mRNA levels increased by 12.0-, 11.0-, 6.6-, 10.0- and 11.0-fold, respectively, coinciding with the change of egg granulomas, i.e., the change in the inflammatory process. Then both collagen and collagenase mRNA levels decreased. Type I, III and IV collagen mRNA levels declined to 2-fold to 3-fold as compared with normal controls (P 0.05) at 28 wks. This study shows that the synthesis and degradation of collagen keep a dynamic balance at the early stage of schistosomiasis japonica challenge, while at the later stages the quantity of collagen synthesis was higher than that of collagen degradation. CONCLUSIONS: It was confirmed at transcription level that when the quantity of collagen synthesis was higher than that of collagen degradation liver fibrogenesis may be resulted in.
基金supported by the National Natural Science Foundation of China (20833010 and 20803045)the Foundation of Ministry of Education of China for New Teachers (200804221008)
文摘A metal-ligand coordinated surfactant system formed by calcium dodecylsulfate(Ca(DS)2)/tetradecyldimethylamine oxide (C14DMAO)/H2O was studied in terms of surface tension,conductivity,negative-staining TEM,phase behavior and rheological operation.In C14DMAO solution,when Ca(DS)2 is added,metal-ligand complexes form between the Ca 2+and N→O group of C14DMAO.Under this metal-ligand driving force,different phases can be obtained at different concentrations and different ratios of Ca(DS)2 and C14DMAO.At the fixed C14DMAO concentration,L1-phase consisting of spherical micelles forms at first.With the addition of Ca(DS)2,the spherical micelles elongate to be wormlike micelles and then after an L1/L-two phase region,the birefringent vesicle-phase(Lv-phase)region is observed.When Ca(DS)2 concentration continues to increase,a gel-phase region is found after the Lv-phase region and then precipitates of undissolved Ca(DS)2 appear.The transition between different phases is affected by temperature remarkably.The wormlike micellar solutions and vesicle solutions were checked by rheological measurements and showed apparent viscoelasticity at high surfactant concentrations.
