Effect of Magnolia officinalis Cortex Before and After Sweating on Distribution of Intestinal Flora and Levels of 5-HT and SP in IBS-C Rats / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Magnolia officinalis cortex for constipation-type irritable bowel syndrome（IBS-C） rats before and after sweating. MethodIBS-C rat model was established by gavage of ice water， and rats were randomly divided into the blank group， model group， mosapride group（1 mg·kg-1）， M. officinalis cortex group（10 g·kg-1） and sweated M. officinalis cortex group（10 g·kg-1）. The changes of body weight， fecal number and fecal water content of rats were observed， 16S rRNA sequencing was used to detect the structural changes of fecal intestinal flora in rats， the levels of 5-hydroxytryptamine（5-HT） and substance P（SP） in colonic tissues of rats were determined by enzyme-linked immunosorbent assay（ELISA）. ResultCompared with the model group， the fecal water content and fecal number of mosapride group， M. officinalis cortex group and sweated M. officinalis cortex group were significantly increased（P<0.05）. At the phylum level， the top four species of flora abundance were Firmicutes， Bacteroidetes， Spirochaetes and Proteobacteria. Compared with the blank group， the proportion of Firmicutes in the model group was significantly reduced（P<0.05）， while the proportion of Spirochaetes was significantly increased（P<0.05）. Compared with the model group， the proportion of Firmicutes and Spirochaetes in M. officinalis cortex group and sweated M. officinalis cortex group tended to be similar to that in the blank group， and the proportion of Spirochaetes in sweated M. officinalis cortex group was lower than that of M. officinalis cortex group. At the family level， the top four species of flora abundance were Lactobacillaceae， S24_7， Ruminococcaceae， Bacteroidaceae， compared with the blank group， the proportion of Lactobacillaceae in the model group decreased significantly（P<0.05）， and its proportion in the M. officinalis cortex group and sweated M. officinalis cortex group increased significantly after administration（P<0.05）， and the flora structure of the two groups tended to be similar to that of the blank group. At the genus level， the top four species of flora abundance were Lactobacillus， Unspecified_S24_7， Bacteroides and Treponema. Compared with the blank group， the proportion of Lactobacillus in the model group decreased significantly（P<0.05）， while the proportion of Treponema increased significantly（P<0.05）. Compared with the model group， ratio of bacterial structure of Lactobacillus and Treponema in the M. officinalis cortex group and sweated M. officinalis cortex group tended to be similar to those in the blank group， indicating that M. officinalis cortex could restore the intestinal microbial structure of IBS-C rats before and after sweating. Compared with the model group， the 5-HT content in mosapride group was significantly reduced（P<0.05）， the contents of 5-HT and SP in the M. officinalis cortex group and sweated M. officinalis cortex group were significantly increased（P<0.01）， and the sweated M. officinalis cortex group was higher than the M. officinalis cortex group. ConclusionM. officinalis cortex can play a therapeutic role on IBS-C rats by regulating 5-HT pathway and intestinal flora structure before and after sweating.

Advances on the production of organic acids by yeast / 生物工程学报

Organic acids are organic compounds that can be synthesized using biological systems. They often contain one or more low molecular weight acidic groups, such as carboxyl group and sulphonic group. Organic acids are widely used in food, agriculture, medicine, bio-based materials industry and other fields. Yeast has unique advantages of biosafety, strong stress resistance, wide substrate spectrum, convenient genetic transformation, and mature large-scale culture technology. Therefore, it is appealing to produce organic acids by yeast. However, challenges such as low concentration, many by-products and low fermentation efficiency still exist. With the development of yeast metabolic engineering and synthetic biology technology, rapid progress has been made in this field recently. Here we summarize the progress of biosynthesis of 11 organic acids by yeast. These organic acids include bulk carboxylic acids and high-value organic acids that can be produced naturally or heterologously. Finally, future prospects in this field were proposed.

Research Status and hot topics of studies on clinical nutrition in congenital heart disease at home and abroad: visual analysis based on CiteSpace / 中华临床营养杂志

Objective:To analyze the research status and discuss hot topics and development trends of studies on clinical nutrition in congenital heart disease (CHD) at home and abroad, so as to provide reference for Chinese researchers.Method:Studies on clinical nutrition in CHD were retrieved from the databases of CNKI and Web of Science, from the founding of database until 2020. CiteSpace 5.6.R5 was used for visual analysis of authors, countries, institutions, research hotspots and frontiers.Results:A total of 163 Chinese and 1,809 English publications were included. The number of literatures published at home and abroad shows an overall trend of growth. The United States has the largest number of publications, with China in seventh place. Domestic publishing institutions are mainly hospitals, led by Nanjing Children's Hospital affiliated to Nanjing Medical University. Foreign publications are mainly by university institutions, with Harvard University in the United States ranking first. Research teams led by authors including Gu Ying and Ravishankar C. are at the core in this field. The most discussed issues in China are mainly nutritional risk, nutritional support and nutrient research. The main target populations are ICU patients, premature infants, infants and children, etc. The forefront of research includes early enteral nutrition, prognosis and feeding intolerance. In foreign countries, studies mainly focus on epidemiology, nutritional support, malnutrition, risk factors, nutritional treatment, energy metabolism, obesity, clinical outcomes, etc. Main target population is special population, such as neonates with CHD, infants, children, patients after heart transplantation, etc. cohort studies and researches on overweight are at the frontier.Conclusions:The research on nutrition in CHD has attracted more and more attention. There are some differences in research content and hot topics between domestic and foreign studies. Therefore, we should strengthen the cooperation and exchanges among institutions, combine the advantages of CHD nutrition research in China, and strengthen the epidemiological study of CHD nutrition and the nutrition management of CHD key population, so as to further promote research development in this field.