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The effects of dynamic high-pressure microfluidization (DHPM at 400 MPa) and heat treatment (HT) on the microbial inactivation, quality parameters, and flavor components of not-from-concentrate (NFC) cucumber juice were investigated. Total aerobic bacteria, yeasts and molds were not detected in the 400 MPa-treated cucumber juice. Total phenolic content increased by 16.2% in the 400 MPa-treated cucumber juice compared to the control check (CK). The significant reduction in pulp particle size (volume peak decreasing from 100–1000 µm to 10–100 µm) and viscosity increased the stability of the cucumber juice while decreasing the fluid resistance during processing. HT decreased the ascorbic acid content by 25.9% (p < 0.05), while the decrease in ascorbic acid content was not significant after 400 MPa treatment. A total of 59 volatile aroma substances were identified by gas chromatography–ion mobility spectrometry (GC-IMS), and a variety of characteristic aroma substances (i.e., valeraldehyde, (E)-2-hexenal, (E)-2-nonenal, and (E,Z)-2,6-nonadienal, among others) were retained after treatment with 400 MPa. In this study, DHPM technology was innovatively applied to cucumber juice processing with the aim of providing a continuous non-thermal processing technology for the industrial production of cucumber juice. Our results provide a theoretical basis for the application of DHPM technology in cucumber juice production. [ABSTRACT FROM AUTHOR]

Foodborne pathogens are serious challenges to food safety and public health worldwide. Fermentation is one of many methods that may be used to inactivate and control foodborne pathogens. Many studies have reported that lactic acid bacteria (LAB) can have significant antimicrobial effects. The current review mainly focuses on the antimicrobial activity of LAB, the mechanisms of this activity, competitive growth models, and application of LAB for inhibition of foodborne pathogens. [ABSTRACT FROM AUTHOR]

Alternaria sp. MG1, an endophytic fungus previously isolated from Merlot grape, produces resveratrol from glucose, showing similar metabolic flux to the phenylpropanoid biosynthesis pathway, currently found solely in plants. In order to identify the resveratrol biosynthesis pathway in this strain at the gene level, de novo transcriptome sequencing was conducted using Illumina paired-end sequencing. A total of 22,954,434 high-quality reads were assembled into contigs and 18,570 unigenes were identified. Among these unigenes, 14,153 were annotated in the NCBI non-redundant protein database and 5341 were annotated in the Swiss-Prot database. After KEGG mapping, 2701 unigenes were mapped onto 115 pathways. Eighty-four unigenes were annotated in major pathways from glucose to resveratrol, coding 20 enzymes for glycolysis, 10 for phenylalanine biosynthesis, 4 for phenylpropanoid biosynthesis, and 4 for stilbenoid biosynthesis. Chalcone synthase was identified for resveratrol biosynthesis in this strain, due to the absence of stilbene synthase. All the identified enzymes indicated a reasonable biosynthesis pathway from glucose to resveratrol via glycolysis, phenylalanine biosynthesis, phenylpropanoid biosynthesis, and stilbenoid pathways. These results provide essential evidence for the occurrence of resveratrol biosynthesis in Alternaria sp. MG1 at the gene level, facilitating further elucidation of the molecular mechanisms involved in this strain's secondary metabolism. [ABSTRACT FROM AUTHOR]