Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production o...Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production of natural carotenoids.Rhodobacter sphaeroides is one of most promising bacteria employed for large scale production of carotenoids.In the present study,crtA located in the carotenoids biosynthesis pathway in R.sphaeroides was amplified by PCR.The overexpression vector pRKcrtA was constructed and subsequently transferred into R.sphaeroides,producing the genetically engineered strain R.sphaeroides 2.4.1/pRKcrtA overexpressing crtA.The carotenoid production from the genetically engineered strain was significantly increased.Fermentation procedure was optimized for further enhanced carotenoids production.展开更多
Ginsenoside Rb1, the effective constituent of ginseng, has been demonstrated to play favorable roles in improving the immunity system. However, there is little study on the osteogenesis and angiogenesis effect of Gins...Ginsenoside Rb1, the effective constituent of ginseng, has been demonstrated to play favorable roles in improving the immunity system. However, there is little study on the osteogenesis and angiogenesis effect of Ginsenoside Rb1. Moreover, how to establish a delivery system of Ginsenoside Rb1 and its repairment ability in bone defect remains elusive. In this study, the role of Ginsenoside Rb1 in cell viability, proliferation, apoptosis, osteogenic genes expression, ALP activity of rat BMSCs were evaluated firstly. Then,micro-nano HAp granules combined with silk were prepared to establish a delivery system of Ginsenoside Rb1, and the osteogenic and angiogenic effect of Ginsenoside Rb1 loaded on micro-nano HAp/silk in rat calvarial defect models were assessed by sequential fluorescence labeling, and histology analysis, respectively. It revealed that Ginsenoside Rb1 could maintain cell viability, significantly increased ALP activity, osteogenic and angiogenic genes expression. Meanwhile, micro-nano HAp granules combined with silk were fabricated smoothly and were a delivery carrier for Ginsenoside Rb1. Significantly, Ginsenoside Rb1 loaded on micro-nano HAp/silk could facilitate osteogenesis and angiogenesis. All the outcomes hint that Ginsenoside Rb1 could reinforce the osteogenesis differentiation and angiogenesis factor’s expression of BMSCs. Moreover, micro-nano HAp combined with silk could act as a carrier for Ginsenoside Rb1 to repair bone defect.展开更多
基金Supported by the Project of Sichuan Science and Technology Department(2019YJ0673)National Modern Agriculture Industry System/Sichuan Live Pig Innovation Team(SCSZTD-3-007)。
文摘Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production of natural carotenoids.Rhodobacter sphaeroides is one of most promising bacteria employed for large scale production of carotenoids.In the present study,crtA located in the carotenoids biosynthesis pathway in R.sphaeroides was amplified by PCR.The overexpression vector pRKcrtA was constructed and subsequently transferred into R.sphaeroides,producing the genetically engineered strain R.sphaeroides 2.4.1/pRKcrtA overexpressing crtA.The carotenoid production from the genetically engineered strain was significantly increased.Fermentation procedure was optimized for further enhanced carotenoids production.
基金supported by National Natural Science Foundation of China (81600828)Shanghai Sailing Program (16YF1406600)
文摘Ginsenoside Rb1, the effective constituent of ginseng, has been demonstrated to play favorable roles in improving the immunity system. However, there is little study on the osteogenesis and angiogenesis effect of Ginsenoside Rb1. Moreover, how to establish a delivery system of Ginsenoside Rb1 and its repairment ability in bone defect remains elusive. In this study, the role of Ginsenoside Rb1 in cell viability, proliferation, apoptosis, osteogenic genes expression, ALP activity of rat BMSCs were evaluated firstly. Then,micro-nano HAp granules combined with silk were prepared to establish a delivery system of Ginsenoside Rb1, and the osteogenic and angiogenic effect of Ginsenoside Rb1 loaded on micro-nano HAp/silk in rat calvarial defect models were assessed by sequential fluorescence labeling, and histology analysis, respectively. It revealed that Ginsenoside Rb1 could maintain cell viability, significantly increased ALP activity, osteogenic and angiogenic genes expression. Meanwhile, micro-nano HAp granules combined with silk were fabricated smoothly and were a delivery carrier for Ginsenoside Rb1. Significantly, Ginsenoside Rb1 loaded on micro-nano HAp/silk could facilitate osteogenesis and angiogenesis. All the outcomes hint that Ginsenoside Rb1 could reinforce the osteogenesis differentiation and angiogenesis factor’s expression of BMSCs. Moreover, micro-nano HAp combined with silk could act as a carrier for Ginsenoside Rb1 to repair bone defect.
