Low-temperature plasma modification, structural characterization and anti-diabetic activity of an apricot pectic polysaccharide.

To fully research the anti-diabetic activity of apricot polysaccharide, low temperature plasma (LTP) was used to modify apricot polysaccharide. The modified polysaccharide was isolated and purified using column chromatography. It was found that LTP modification can significantly improve the α-glucosidase glucosidase inhibition rate of apricot polysaccharides. The isolated fraction FAPP-2D with HG domain showed excellent anti-diabetic activity in insulin resistance model in L6 cell. We found that FAPP-2D increased the ADP/ATP ratio and inhibited PKA phosphorylation, activating the LKB1-AMPK pathway. Moreover, FAPP-2D activated AMPK-PGC1α pathway, which could stimulated mitochondrial production and regulate energy metabolism, promoting GLUT4 protein transport to achieve an anti-diabetic effect. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy data showed that the LTP modification could increase the CH bond content while decreasing the C-O-C/C-O bond content, indicating that LTP destroyed the C-O-C/C-O bond, which enhanced the anti-diabetes activity of the modified apricot pectin polysaccharide. Our findings could pave the way for the molecular exploitation of apricot polysaccharides and the application of low-temperature plasma.

Age-dependent alteration in metabolism of vitamin B6 , neurotransmitters, and amino acids after 4'-O-methylpyridoxine administration in rats.

4'-O-methylpyridoxine (MPN), a recognized antivitamin B6 compound, is a potentially poisonous substance found in Ginkgo biloba L. In this work, the effects of MPN on the metabolism of vitamin B6 , neurotransmitters, and amino acids were compared in the plasma and brain of young and adult rats under various administration times. Results showed that the contents of MPN residues in the plasma and brain of young rats were 12.72 and 14.76 µM higher than adult rats, respectively. Moreover, the levels of 5-hydroxytryptamine and dopamine in the brain of young rats have decreased by 13.78% and 7.19%, respectively, compared with the control group, at 2 h after MPN administration. Furthermore, the principal component analysis revealed that MPN was an important contributor to the amino acid composition in the brain of young rats. These results suggest that age may lead to different toxic effects of MPN. PRACTICAL APPLICATION: 4'-O-methylpyridoxine is primarily responsible for poisoning due to overconsumption of Ginkgo biloba seeds. This study will provide an exploratory understanding of the age-dependent toxicity of 4'-O-methylpyridoxine.

In vivo toxicity assessment of 4'-O-methylpyridoxine from Ginkgo biloba seeds: Growth, hematology, metabolism, and oxidative parameters.

4'-O-methylpyridoxine (MPN), a recognized antivitamin B6 compound, is a potentially poisonous substance found in Ginkgo biloba seeds and leaves. In this work, the body weights, histopathological changes, plasma vitamin B6 (VB6), biochemical parameters, oxidative stress responses, and amino acids of rats were investigated after intragastric administration of MPN for 15 days. Results showed that intragastric administration of 50 mg/kg BW MPN caused pathological changes in the brain and heart tissues of rats. Administration of 10 mg/kg and 30 mg/kg BW MPN can significantly increase VB6 analogs in the plasma of rats, such as pyridoxal-5'-phosphate, pyridoxal. Results of biochemical parameters indicated that MPN can damage brains and hearts by changing the enzyme activity of these organs. These results suggest that consumption of Ginkgo biloba seeds for the long term, even in a small quantity, may lead to poisoning.

4'-O-methylpyridoxine: Preparation from Ginkgo biloba Seeds and Cytotoxicity in GES-1 Cells.

Ginkgo biloba seeds are wildly used in the food and medicine industry. It has been found that 4'-O-methylpyridoxine (MPN) is responsible for the poisoning caused by G. biloba seeds. The objective of this study was to explore and optimize the extraction method of MPN from G. biloba seeds, and investigate its toxic effect on human gastric epithelial cells (GES-1) and the potential related mechanisms. The results showed that the extraction amount of MPN was 1.933 µg/mg, when extracted at 40 °C for 100 min, with the solid-liquid ratio at 1:10. MPN inhibited the proliferation of GES-1 cells, for which the inhibition rate was 38.27% when the concentration of MPN was 100 µM, and the IC50 value was 127.80 µM; meanwhile, the cell cycle was arrested in G2 phase. High concentration of MPN (100 µM) had significant effects on the nucleus of GES-1 cells, and the proportion of apoptotic cells reached 43.80%. Furthermore, the Western blotting analysis showed that MPN could reduce mitochondrial membrane potential by increasing the expression levels of apoptotic proteins Caspase 8 and Bax in GES-1 cells. In conclusion, MPN may induce apoptosis in GES-1 cells, which leads to toxicity in the human body.

Influence of illumination on the greening and relative enzyme activity of garlic puree.

Garlic has attracted considerable attention because of its bactericidal and anticancer effects. However, the greening of garlic purees greatly affects the product quality. This study investigated the influence of light colors and power on the greening of garlic, and determined the key substances of garlic puree greening, including γ-glutamyl transpeptidase (γ-GT), thiosulfinate, and alliinase. Results showed that purple light source greatly affects greening power, γ-GT, and thiosulfinate. Illumination using a 3-W power lamp could reduce the production of thiosulfinate and alliinase and inhibit the green transformation reaction. Illumination using a 5-W power lamp greatly affected the thiosulfinate content and greening power, whereas that using a 7-W power lamp greatly influenced the γ-GT activity, porphobilinogen content, and alliinase content. Results showed that the green color of garlic puree is greatly affected by the illumination color and intensity, which provides theoretical support for the anti-greening of light garlic puree. PRACTICAL APPLICATION: Because garlic puree easily turns green during processing, which affects the product quality and economic value, this study uses controllable light source radiation to influence the greening of garlic puree, hoping to delay or even solve this problem and provide a new simple method to prevent garlic puree from turning greening.

Influence of packaging materials on postharvest physiology and texture of garlic cloves during refrigeration storage.

This study aims to investigate the postharvest physiology and texture of garlic cloves packaged in polyethylene terephthalate (PET), polyethylene (PE), aluminized kraft paper (AKP), single kraft paper (SKP), and mesh bag. Germination rate, electrical conductivity, respiration intensity, water content, and texture were determined during 180 d storage at -2 °C. Results showed that the germination of garlic cloves packaged in PET, PE, and AKP was effectively inhibited during storage. PE effectively reduced the degree of damage to the cell membranes of the garlic cloves. PE and SKP significantly inhibited respiratory intensity during storage. Garlic cloves water content did not change significantly in 90 d storage which packaged in PE and SKP. PE exhibited better effect on the texture and freshness of garlic cloves than the other materials. In conclusion, PE is the best packaging material for maintaining the quality attributes and extending the shelf lives of garlic cloves.

Determination and Comparison of 4'- O-Methylpyridoxine Analogues in Ginkgo biloba Seeds at Different Growth Stages.

The antivitamin B6, 4'- O-methylpyridoxine (MPN); its glucoside, 4'- O-methylpyridoxine-5'-glucoside (MPNG); and vitamin B6 compounds, including pyridoxal (PL), pyridoxamine, pyridoxine, pyridoxal-5'-phosphate (PLP), and pyridoxamine-5'-phosphate, exist in Ginkgo biloba seeds, which are widely used as food and medicine. This work aimed to determine the MPN analogues in G. biloba seeds at different growth stages in terms of cultivars and ages of trees. The highest total MPN contents of 249.30, 295.62, and 267.85 µg/g were obtained in the mature stages of three selected G. biloba samples. The total contents of vitamin B6 compounds decreased significantly in the entire growth period of the three samples. Principal-component analysis revealed that MPN and MPNG were important contributors in the MPN-analogue metabolism of G. biloba seeds. The influence of the cultivar on the content and composition of MPN analogues was greater than that of the age of the G. biloba tree.

Comparison of Phytochemicals and Antioxidant Capacity in Three Bean Varieties Grown in Central Malawi.

The aims of the current work were: (1) to study the influence of variety and geographical production area on the total phenolic content, total anthocyanin content, total flavonoid content, total carotenoid content and antioxidant activity in bean varieties (Dimeta, Napirira and Nanyati) from different growing areas in central Malawi, and (2) to evaluate the possibility of establishing a classification based on the geographical areas of the growing regions. A total of 47 bean samples were collected from Makowe, Mphathi, Chuma-Chitsala and Khulungira Zone. These four locations were segregated based on altitude, latitude and longitude. Principal component and hierarchical cluster analysis were used to distinguish and classify among these samples. Significant differences (P < 0.05) in total phenolic content (2.92-4.97 mg/g), total anthocyanin content (14.52-152.31 µg/g), total flavonoid content (2.01-6.38 mg/g) and oxygen radical absorbance capacity (16.75-24.51 µmol/g) were found among the different sampled villages, showing a significant effect of the producing region on these parameters. The beans in Makowe had lower polyphenols than in other locations. Results of principal component analysis indicate that phytochemicals and antioxidant capacity could serve as parameters to establish a bean classification according to the geographical area of production.

Allergic identification for ginkgo kernel protein in guinea pigs.

Ginkgo biloba L. can cause allergic reactions when consumed. In this paper, an allergy test to guinea pig was investigated. Guinea pigs were sensitized with 50 mg/mL of ginkgo kernel protein orally on days 1, 3, and 5, and intraperitoneally challenged with 100mg/mL of the protein on day 7 after the last sensitization. The volume of sensitization and challenge was 0.20mL/100 g weight. The results showed the average allergy grade for guinea pigs reached four and the allergy rate was 100%. The immunoglobulin G and E levels in sera were significantly higher than those in the controls. Footpads swelled distinctly, and the passive cutaneous allergy test manifested a positive response. There were inflammatory changes in the lungs and intestines. In conclusion, the present results may indicate that gingko kernel protein has an allergenic capacity.

Production of cordycepin and mycelia by submerged fermentation of Cordyceps militaris in mixture natural culture.

The submerged fermentation of Cordyceps militaris for cordycepin production and mycelial growth was investigated in this study. Three natural materials of brown rice paste (BRP), beerwort (B), and soybean meal juice (SMJ) were used for fermentation of C. militaris in shaking flasks. The effects of the ratio of three natural materials on dry mycelium weight (DMW) and on cordycepin yield (CY) were analyzed. D-Optional mixture design was used to optimize the ratio of these materials. Compared with the signal culture, the higher mycelial growth and cordycepin production were obtained in mixture. The analysis of Design Expert 6.0 indicated that BRP, B, and SMJ very significantly influenced (P < 0.001) DMW and CY of C. militaris, respectively. The highest DMW (18.96 g/l) and CY (2.17 mg/g) were both obtained at a ratio of 53:6:42. The experiments' results indicated that the above mixture of these natural materials by D-optional mixture design can be used as a proper medium for the growth of mycelium and the production of cordycepin.