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Objective: To investigate the effects of electron beam irradiation on the physicochemical properties and antioxidant activity of non-waxy and waxy proso millet. Methods: waxy (‘Yushu 1’) and non-waxy (‘Yumi 2’) proso millet were subjected to electron beam irradiation at different doses of 0 (control), 2, 4, 6, 8, and 10 kGy and were evaluated for physicochemical properties, bioactive substances and antioxidant capacity. Results: After electron beam irradiation, the color, starch content, ash content, phenolic content and antioxidant activity of non-waxy and waxy proso millet changed significantly (P 0.05). In addition, electron beam irradiation treatment significantly increased the contents of total phenols and total flavonoids, antioxidant activity and individual phenolic contents in non-waxy and waxy proso millet; the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity increased up to 78.01% and 70.22%, and the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation scavenging capacity increased up to 61.51% and 50.57%, respectively. The contents of gallic acid, caffeic acid, resveratrol, catechin and kaempferol in proso millet extract increased, while the contents of protocatechuic acid and epicatechin remained relatively stable. The correlation analysis suggested that the total phenolic content had a significantly positive correlation with the contents of catechin and quercetin (P < 0.01), the total flavonoid content had a significantly positive correlation with the contents of rutin and gallic acid (P < 0.01), and the antioxidant activity was positively correlated with the catechin content. Compared with the control, proso millet treated with electron beam irradiation exhibited stronger antioxidant properties and higher phenolic contents, which would be worthy of further research and development.

Summary: The purpose of this study was to investigate the fermentation characteristics of five varieties of fig juices (Ficus carica cv. Siluhongyu, Siluhuangjin, Silufeicui, Jinaofen and Fengchanhuang) by two select strains (Lactobacillus plantarum and Lactobacillus acidophilus), based on the changes of physicochemical parameters, bioactive components, antioxidant activities and flavour volatiles. Viable counts were above 9.5 log CFU mL−1 throughout the fermentation process, indicating that fig juices were suitable substrates for strain proliferation. Total phenolic and flavonoid contents were significantly enhanced during fermentation, particularly with Siluhuangjin by L. plantarum and Silufeicui by L. acidophilus, exhibiting the highest total phenolic (465 mg GAE L−1) and total flavonoid contents (152 mg RE L−1), respectively. Accordingly, antioxidant activities based on SOD, DPPH, ABTS and FRAP methods were significantly improved after fermentation (P < 0.05). SOD and ABTS were positively correlated with contents of protocatechuic acid and caffeic acid, respectively (P < 0.05). Furthermore, alcohols, ketones and terpenoids contents were increased, while aldehydes content was decreased significantly after fermentation (P < 0.05), suggesting the improved flavour characteristics of fermented fig juices. [ABSTRACT FROM AUTHOR]

Subcritical water extraction (SWE) and hot water extraction (HWE) were used to extract polysaccharides from Morchella sextelata (MSP). The physicochemical and structural characteristics and biological properties of MSPSWE and MSPHWE were evaluated. SWE achieved a higher crude MSP yield (18.09 ± 0.09%) than HWE (4.95 ± 0.05%; p <.01). Using SWE, MSPSWE showed a higher total sugar content and fat‐binding capacity. MSPSWE and MSPHWE contained the same monosaccharides, but with significantly different average molecular weights and microstructures without alterations in the main chemical structure, as revealed via FT‐IR and nuclear magnetic resonance (NMR) spectroscopy. DSC analysis revealed favorable thermal stability. Biological activity assays elucidated that MSPSWE had stronger antioxidant activity in vitro and significantly promoted RAW264.7 cell proliferation and nitric oxide production. Therefore, MSPSWE may represent a potent antioxidant and immunomodulator in the functional food field, with SWE serving as an effective method for extracting highly bioactive M. sextelata polysaccharides. Novelty impact statement: The molecular weight of Morchella sextelata polysaccharides (MSPs) decreased following subcritical water extraction (SWE), which also improved their yield (from 4.95% to 18.09%). Furthermore, the MSPs obtained via SWE showed stronger antioxidant and immunomodulatory activities than those obtained via hot water extraction. [ABSTRACT FROM AUTHOR]