There is a close relationship between crassulacean acid metabolism and drought tolerance,and a great number of landscape plants which consume less water are necessary to build economic garden.In order to provide the b...There is a close relationship between crassulacean acid metabolism and drought tolerance,and a great number of landscape plants which consume less water are necessary to build economic garden.In order to provide the basis for selecting drought-tolerant landscape plants,five species of plants were employed,including Dendrobium chrysotoxum,D.nobile,D.primulinum,Kalanchoblossfeldiana and K.daigremontiana.Exposed to different intensities of light,various samples were collected.The slices were prepared via different techniques.Stomatal movements and stomatal complex structures were observed by scanning electronic microscope and confocal laser scanning microscope.The results indicated that the slices made rapidly from fresh leaves were conductive to inspecting actual stomatal movements and stomatal complex structures as soon as possible.It was found that the stomatal movement of K.daigremontiana,K.blossfeldiana and D.primulinum displayed typical characteristics of crassulacean acid metabolism,while that of D.chrysotoxum and D.nobile did not exhibited obvious characteristics of crassulacean acid metabolism.展开更多
Cordycepin,which has great immunomodulatory activities such as anticancer,antifungal,antivirus,antileukemia and lipid-lowering ones,is the secondary metabolite of Cordyceps militaris(C.militaris).Liquid submerged ferm...Cordycepin,which has great immunomodulatory activities such as anticancer,antifungal,antivirus,antileukemia and lipid-lowering ones,is the secondary metabolite of Cordyceps militaris(C.militaris).Liquid submerged fermentation is the common cultivation process to produce cordycepin.To optimize the fermentation process and improve production,monitoring the cordycepin secretion in the fermentation is essential.The measurement based on chromatography-mass spectrometry methods is generally involved in the complex sample pretreatments and time-consuming separation,so more rapid and convenient methods are required.Matrix-assisted laser desorption ionization mass spectrometry(MALDI-MS)is more attractive for faster and direct detection.Therefore,MALDI-MS detection combined with isotope-labeled internal standard was applied to the measurement of cordycepin content in the fermentation broth and mycelium.This method made accurate quantification of cordycepin in the range of 5-400μg/mL with a relative standard deviation of 5.6%.The recovery rates of fermentation samples after the 1,13,and 25 days were 90.15%,94.27%,and 95.06%,respectively.The contents of cordycepin in the mycelium and fermentation broth were 136 mg/g and 148.39 mg/mL on the 20 th culture day,respectively.The cordycepin secretion curve of the liquid fermentation of C.militaris was real-time traced over 25 days.展开更多
Intestinal flora play an important role in human's immune system. Many bacteria adhere to the wall of the testinal wall. These Intestinal flora help digestion, and also stop their disease-causing counterparts from...Intestinal flora play an important role in human's immune system. Many bacteria adhere to the wall of the testinal wall. These Intestinal flora help digestion, and also stop their disease-causing counterparts from invading. Most of the current researches focused on the interaction between cells and the construction of organs, but few researches studied on the role of microorganisms and cells. Here, we developed an in vitro living cell systems to simulate the structure, absorption, transport and pathophysiological characteristics of the human intestinal tract and the key microbial symbiosis. The co-culture of Clostridium butyricum(C.butyricum) and colon cancer cells showed a different immune effect. C. butyricum could inhibit the proliferation of HCT116 cells, cause cell cycle arrest and promote apoptosis. But it had no significant effect on Caco-2 cells. Thus, basic functional characteristics of the gut were successfully simulated in a controlled microfluidic system. This approach is suggested as a powerful method in the investigation on drug metabolism and intestinal diseases.展开更多
基金Supported by Activity Plan of Scientific Research and Entrepreneurship for Beijing College Students(NO.S201410022035)
文摘There is a close relationship between crassulacean acid metabolism and drought tolerance,and a great number of landscape plants which consume less water are necessary to build economic garden.In order to provide the basis for selecting drought-tolerant landscape plants,five species of plants were employed,including Dendrobium chrysotoxum,D.nobile,D.primulinum,Kalanchoblossfeldiana and K.daigremontiana.Exposed to different intensities of light,various samples were collected.The slices were prepared via different techniques.Stomatal movements and stomatal complex structures were observed by scanning electronic microscope and confocal laser scanning microscope.The results indicated that the slices made rapidly from fresh leaves were conductive to inspecting actual stomatal movements and stomatal complex structures as soon as possible.It was found that the stomatal movement of K.daigremontiana,K.blossfeldiana and D.primulinum displayed typical characteristics of crassulacean acid metabolism,while that of D.chrysotoxum and D.nobile did not exhibited obvious characteristics of crassulacean acid metabolism.
基金financially supported by Fundamental Research Funds for the Central Universities(Grant No.2019ZY31)the National Natural Science Foundation of China(Grant Nos.21775086 and 31770110)。
文摘Cordycepin,which has great immunomodulatory activities such as anticancer,antifungal,antivirus,antileukemia and lipid-lowering ones,is the secondary metabolite of Cordyceps militaris(C.militaris).Liquid submerged fermentation is the common cultivation process to produce cordycepin.To optimize the fermentation process and improve production,monitoring the cordycepin secretion in the fermentation is essential.The measurement based on chromatography-mass spectrometry methods is generally involved in the complex sample pretreatments and time-consuming separation,so more rapid and convenient methods are required.Matrix-assisted laser desorption ionization mass spectrometry(MALDI-MS)is more attractive for faster and direct detection.Therefore,MALDI-MS detection combined with isotope-labeled internal standard was applied to the measurement of cordycepin content in the fermentation broth and mycelium.This method made accurate quantification of cordycepin in the range of 5-400μg/mL with a relative standard deviation of 5.6%.The recovery rates of fermentation samples after the 1,13,and 25 days were 90.15%,94.27%,and 95.06%,respectively.The contents of cordycepin in the mycelium and fermentation broth were 136 mg/g and 148.39 mg/mL on the 20 th culture day,respectively.The cordycepin secretion curve of the liquid fermentation of C.militaris was real-time traced over 25 days.
基金supported by the Fundamental Research Funds for the Central Universities (2016JX03)the National Natural Science Foundation of China (21435002, 31400085, 81373373)
文摘Intestinal flora play an important role in human's immune system. Many bacteria adhere to the wall of the testinal wall. These Intestinal flora help digestion, and also stop their disease-causing counterparts from invading. Most of the current researches focused on the interaction between cells and the construction of organs, but few researches studied on the role of microorganisms and cells. Here, we developed an in vitro living cell systems to simulate the structure, absorption, transport and pathophysiological characteristics of the human intestinal tract and the key microbial symbiosis. The co-culture of Clostridium butyricum(C.butyricum) and colon cancer cells showed a different immune effect. C. butyricum could inhibit the proliferation of HCT116 cells, cause cell cycle arrest and promote apoptosis. But it had no significant effect on Caco-2 cells. Thus, basic functional characteristics of the gut were successfully simulated in a controlled microfluidic system. This approach is suggested as a powerful method in the investigation on drug metabolism and intestinal diseases.
