Ultra-high-depth macrogenomic sequencing revealed differences in microbial composition and function between high temperature and medium-high temperature Daqu

Complex microorganisms in Daqu of different temperatures play a vital role in the taste, flavor and quality of Baijiu during fermentation. However, understanding the functional diversity of the whole microbial community between the Daqus of two different temperatures (high temperature Daqu, HD and medium-high temperature Daqu, MD) remains a major challenge. Here, a systematic study of the microbial diversity, functions as well as physiological and biochemical indexes of Daqu are described. The results revealed that the Daqu exhibited unique characteristics. In particular, the diversity of microorganisms in HD and MD was high, with 44 species including 14 novel species (Sphingomonas sp. is the main novel species) detected in all samples. Their profiles of carbohydrate-active enzymes and specific functional components supported the fact that these species were involved in flavor formation. The Daqu microbiome consisted of a high proportion of phage, providing evidence of phage infection/genome integration and horizontal gene transfer from phage to bacteria. Such processes would also regulate Daqu microbiomes and thus flavor quality. These results enrich current knowledge of Daqu and can be used to promote the development of Baijiu fermentation technology.

Novel Insights into the Physiology of Nutrient Sensing and Gut-Brain Communication in Surgical and Experimental Obesity Therapy

Despite standardized surgical technique and peri-operative care, metabolic outcomes of bariatric surgery are not uniform. Adaptive changes in brain function may play a crucial role in achieving optimal postbariatric weight loss. This review follows the anatomic-physiologic structure of the postbariatric nutrient-gut-brain communication chain through its key stations and provides a concise summary of recent findings in bariatric physiology, with a special focus on the composition of the intestinal milieu, intestinal nutrient sensing, vagal nerve-mediated gastrointestinal satiation signals, circulating hormones and nutrients, as well as descending neural signals from the forebrain. The results of interventional studies using brain or vagal nerve stimulation to induce weight loss are also summarized. Ultimately, suggestions are made for future diagnostic and therapeutic research for the treatment of obesity.

Discovery of active ingredients in Traditional Chinese Medicine based on odor and flavor compounds analysis

BACKGROUND

The odor and flavor produced by a complex mixture of chemical components with different amounts and thresholds, which is the unique property for food and Traditional Chinese Medicine (TCM). These compounds usually belong to mono- and sesquiterpenes, esters, lipids, and others.

OBJECTIVE

This review was aimed to demonstrate the extraction method and reliable technology for identifying the compounds responsible for their odor and flavor.

METHOD

Summarize existing techniques for the analysis of taste and odor components and their characteristics, such as electronic nose (enose, EN) and electronic tongue (etongue, ET), which can separate the high-quality food from low quality, natural from artificial food in terms of unique odor and flavor.

RESULTS

Gas chromatography-olfactometry mass spectrometry (GC-O-MS), a technique coupled Gas chromatography mass spectrometry (GC-MS) with human sense by Olfactory Detector Ports, has been successfully applied for screening the odor-producing components with representative odor for the food or Chinese medicine.

CONCLUSION

This current review provides some guidelines for quality evaluation of food or Chinese medicine.