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Liuyang Douchi is a kind of traditional fermented Aspergillus -type Douchi in China for excellent favor. However, studies on the microbial diversity and the characterization of predominate fungi of Liuyang Douchi are few. In present study, the Illumina HiSeq sequencing was performed to reveal the fluctuation characteristics of microbial diversity during fermentation. Results showed that Staphylococcus (33.86%), Staphylococcaceae_unclassified (27.39%) and Pediococcus (8.80%) were the dominated bacteria, while Petromyces (74.57%), Rhizopus (10.93%) and Penicillium (2.68%) were the most predominant fungi during entire fermentation period. Intriguingly, Petromyces was negatively correlated with Alternaria, Saccharomyces and Saccharomycetales_unclassified. Further, four non-aflatoxigenic Aspergillus flavus strains were first identified and isolated from Liuyang Douchi according to phylogenetic and macroscopic characteristics. These four Aspergillus flavus displayed high cellulase and protease activities, but weak lipase activity. This study could contribute to the quality control of Liuyang Douchi by providing an overview of the microbial diversity. • Staphylococcus and Pediococcus was the dominated bacteria in qu-making period and pile fermentation, respectively. • Petromyces were the predominant fungi in Douchi that was negative correlated with Alternaria and Saccharomyces. • Four Aspergillus flavus strains isolated from Douchi displayed high cellulase and protease activity. • No aflatoxin B1 was detected in these four strains in conditions provided. [ABSTRACT FROM AUTHOR]

Citri Reticulatae Pericarpium (CRP), has been used in China for hundreds of years as a functional food and medicine. However, some short-age CRPs are disguised as long-age CRPs by unscrupulous businessmen in order to obtain higher profits. In this paper, a rapid and nondestructive method for the classification of different-age CRPs was established using portable near infrared spectroscopy (NIRS) in diffuse reflectance mode combination with appropriate chemometric methods. The spectra of outer skin and inner capsule of CRPs at different storage ages were obtained directly without destroying the samples. Principal component analysis (PCA) with single and combined spectral pretreatment methods was used for the classification of different-age CRPs. Furthermore, the data were pretreated with the PCA method, and Fisher linear discriminant analysis (FLD) with optimized pretreatment methods was discussed for improving the accuracy of classification. Data pretreatment methods can be used to eliminate the noise and background interference. The classification accuracy of inner capsule is better than that of outer skin data. Furthermore, the best results with 100% prediction accuracy can be obtained with FLD method, even without pretreatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bacterial succession of different salinity peppers within 10 months storage is revealed. • Salinity and storage time greatly effected the composition and structure of bacteria. • Lactobacillus's growth was inhibited at over 15% salinity. • The addition of 12% salt is beneficial to the long-term preservation of salted peppers. Chopped pepper is one of the traditional fermented pepper products in China. At present, the industrial production method is mainly to preserve the peppers with high salt about 1 year, and then make the product after desalination and seasoning when it is processed. However, the composition and succession of the bacterial community involved in the long-term preservation of salted pepper was complex. In this study, Illumina Miseq sequencing technology was used to reveal the succession in the bacterial community structure of different salted pepper within 10 months of preservation. The results showed that Firmicutes and Proteobacteria were dominant bacteria in all samples at the Phylum level. At the Genus level, among fresh unsalted capsicum, Fructobacillus (44.66%), Enterobacteriaceae unclassified (26.78%), Leuconostoc (12.04%) and Lactococcus (8.45%) had relatively high abundance. Enterobacteriaceae unclassified , Lactobacillus , Marinospirillum and Halomonas were identified as the main dominant bacteria in the samples with 6%-12% (w/w) salinity, and Enterobacteriaceae unclassified mainly appeared in the early stage of preservation. In 15% and 18%(w/w) salinity samples, with the increase of preservation time, the dominant genus was changed from Enterobacteriaceae unclassified to Chromohalobacterter , Tetragenococcus , Halomonas , Halovibrio , etc., while the relative abundance of Lactobacillus remained at an extremely low level. The bacterial structure of 6% (w/w) salinity samples changed significantly during preservation, while the distribution in PCoA analysis of salinity samples of 9% was similar to that of 12%. In the high-salinity samples (15%-18%), the composition of the community was highly similar in 0–6 months, but the composition changed significantly with the increase of the preservation time and the growth of halophilic bacteria (p < 0.01). Pearson correlation analysis was used to investigate that Lactobacillus exhibited a negative correlation with salinity (p < 0.01). And the salinity had a positive correlation with both the species richness and evenness in the samples, which might be the key factor for the change of the microbial community. [ABSTRACT FROM AUTHOR]