Machine Learning-Assisted Portable Microplasma Optical Emission Spectrometer for Food Safety Monitoring.

To meet the needs of food safety for simple, rapid, and low-cost analytical methods, a portable device based on a point discharge microplasma optical emission spectrometer (µPD-OES) was combined with machine learning to enable on-site food freshness evaluation and detection of adulteration. The device was integrated with two modular injection units (i.e., headspace solid-phase microextraction and headspace purge) for the examination of various samples. Aromas from meat and coffee were first introduced to the portable device. The aroma molecules were excited to specific atomic and molecular fragments at excited states by room temperature and atmospheric pressure microplasma due to their different atoms and molecular structures. Subsequently, different aromatic molecules obtained their own specific molecular and atomic emission spectra. With the help of machine learning, the portable device was successfully applied to the assessment of meat freshness with accuracies of 96.0, 98.7, and 94.7% for beef, pork, and chicken meat, respectively, through optical emission patterns of the aroma at different storage times. Furthermore, the developed procedures can identify beef samples containing different amounts of duck meat with an accuracy of 99.5% and classify two coffee species without errors, demonstrating the great potential of their application in the discrimination of food adulteration. The combination of machine learning and µPD-OES provides a simple, portable, and cost-effective strategy for food aroma analysis, potentially addressing field monitoring of food safety.

Integrated microbiome-metabolomics analysis reveals the potential therapeutic mechanism of Zuo-Jin-Wan in ulcerative colitis.

BACKGROUND: Dysregulation in gut microbiota and host cometabolome contributes to the complicated pathology of ulcerative colitis (UC), while Zuo-Jin-Wan (ZJW), a traditional Chinese medicine has shown therapeutic effects against UC with its underlying mechanism remains elusive. PURPOSE: This study utilized an integrated analysis combining gut microbiome and host cometabolism to disclose the potential therapeutic mechanism of ZJW on dextran sulfate sodium (DSS)-induced UC in rats. METHODS: We first evaluated the therapeutic effects of ZJW treatment in DSS-induced rat model. 16S rRNA sequencing, 1H NMR spectroscopy-based metabolomics and Spearman correlation analysis were conducted to explore the potential therapeutic mechanism during the treatment. RESULTS: Our results showed that UC symptoms in ZJW rats were significantly attenuated. Marked decline in microbial diversity in ZJW group was accompanied by its correspondent function adjustment. Specific enrichment of genus Bacteroides, Sutterella, Akkermansia and Roseburia along with the major varying amino acid metabolism and lipid metabolism were observed meantime. Metabolic data further corroborated that ZJW-related metabolic changes were basically gathered in amino acid metabolism, carbohydrate/energy metabolism and lipid metabolism. Of note, some biochemical parameters were deeply implicated with the discriminative microbial genera and metabolites involved in tricarboxylic acid (TCA) cycle and amino acid metabolism, indicating the microbiome-metabolome association in gut microbiota-metabolite-phenotype axis during UC treatment of ZJW. CONCLUSION: For the first time, integrated microbiome-metabolome analysis depicted that ZJW could alleviate DSS-induced UC in rats via a crosstalk between gut microbiota and host cometabolites.

Dietary synbiotic ameliorates constipation through the modulation of gut microbiota and its metabolic function.

The purpose of this study is to investigate the mitigatory effect of a novel synbiotic (SBT) on constipation from the perspective of gut microbiome and metabolome. Here, intake of SBT effectively attenuated diphenoxylate-induced constipation, recuperated colonic epithelial integrity and increased serum levels of gastrointestinal excitatory neurotransmitters (P substance, vasoactive intestinal peptide, motilin, gastrin and serotonin). 16S rRNA sequencing showed that SBT intake rehabilitated the composition and functionality of gut microbiota. Relative abundances of short-chain fatty acids (SCFAs)-producing bacteria including Lactobacillus, Faecalibaculum and Bifidobacterium were elevated by administration of SBT. The gas chromatography-mass spectrometry analysis confirmed that fecal concentrations of propionate and butyrate were significantly increased in the rats intervened with SBT. In addition, SBT ingestion reduced the relative levels of opportunistic pathogens, such as Oscillibacter, Parasutterella and Parabacteroides. Microbial functional prediction showed that the relative abundances of lipopolysaccharide (LPS) biosynthesis and arachidonic acid metabolism were downregulated with SBT administration, which were in accordance with the serum metabolomics results. Furthermore, serum levels of LPS, tumour necrosis factor alpha and interleukin 6 were significantly decreased, indicating that SBT supplementation suppressed inflammatory responses. Therefore, this study demonstrated that consumption of SBT ameliorated constipation possibly by regulating gut microbiota, promoting the SCFAs production and inhibiting inflammatory responses in rats. Our study also indicated that SBT may provide a novel alternative strategy for the treatment of constipation clinically in future.