To elucidate the impact of microorganisms on the metabolites and flavor of Xuanwei ham, the correlation between volatile compounds, small molecule metabolites, and microbial communities in Xuanwei ham was studied. The results showed that the predominant bacteria and fungi were Proteobacteria , Firmicutes , and Ascomycota , respectively at the phylum level, and the main bacteria was Staphylococcus , and the predominant fungi was Aspergillus at the genus level. A total of 48 differential metabolites were screened, and amino acids were the most abundant. Upon pathway analysis, 21 metabolic pathways were found to be related to ham ripening. More than 20 key metabolites such as arginine were accurately matched by Public Chemistry Database (Pub Chem) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Eighteen volatile flavor characteristic compounds were identified, and the relative content of acetone in ham samples from various years was the highest. Additionally, the findings explored the relationship between small molecule metabolites, volatile compounds, and microorganisms in Xuanwei ham, which showed that the microorganisms in the samples had a positive effect on a variety of amino acids and alcohols. The findings represent a fertile ground for the formation of ham quality.
Summary Xuanwei ham is a kind of traditional meat product with unique flavour along with abundant of bioactive peptides. This study was to investigate the in vitro stability of bioactive peptide extract from dry-cured Xuanwei hams and its anti-inflammatory effect in RAW264.7 cells. Firstly, the Xuanwei ham peptides (XHPs) were extracted and then tested in the lipopolysaccharide (LPS)-induced macrophage cell model. Furthermore, the XHPs were exposed to different pretreatments including heating, acid-base environment and simulated gastrointestinal digestion to evaluate their inflammatory regulation capacity. The heating temperature and pH did not show significant effects on the anti-inflammatory capacity of XHPs, whereas the secretion of NO and TNF-α was not suppressed after heating at 100 °C for 60 min. After digestion, the numbers of free amino acids and short peptides were enhanced significantly and the XHPs showed better inhibitory effect on LPS-induced NO and TNF-α secretion. Overall, the heating and pH treatment had no significant influence on the stability of XHPs but the anti-inflammatory effect was enhanced after the simulated gastrointestinal digestion along with the releasing of novel bioactive peptides.
YiXun Li,Huan Li,Yong Duan,XueMei Cai,DingYun You,Feng Zhou,ChuanQi Yang,XiaoYu Tuo,ZiJie Liu
Background. Xuanwei City in Yunnan province has been one of the towns with highest lung cancer mortality in China. The high content of amorphous silica in the bituminous coal from Xuanwei of Yunnan is mainly present as irregular and spherical silica nanoparticles (SiNPs). It has been reported that silica nanoparticles in bituminous coal correlated with the high incidence of lung cancer in Xuanwei. To explore the role and mechanism of SiNPs in the tumorigenesis of lung cancer in Xuanwei, human mononuclear cells (THP-1) and human bronchial epithelial cells (BEAS-2B) were cocultured in a transwell chamber. Combined with Benzo[a]pyrene-7, 8-dihydrodiol-9, and 10-epoxide (BPDE), SiNPs could significantly promote the proliferation and Epithelial-Mesenchymal Transition (EMT) and inhibit apoptosis of BEAS-2B cells and induce the release of TGF-α from THP-1 cells. After neutralizing TGF-α with antibody, the proliferation and EMT were decreased and enhanced apoptosis of BEAS-2B cells. Furthermore, the results showed that TGF-α in the sera of patients with lung adenocarcinoma in Xuanwei were significantly higher than in patients with benign pulmonary lesions in Xuanwei and those with lung adenocarcinoma in outside of Xuanwei of Yunnan. Taken together, our study found that SiNPs promoted the proliferation and EMT of BEAS-2B cells by inducing the release of TGF-α from THP-1 cells.
危险品化学品经营许可证（带存储）