Academic Journal of Materials & Chemistry, 2023, 4(7); doi: 10.25236/AJMC.2023.040701.
Yidong Yin1, Leran Yang2
1Department of Chemistry, Langara College, Vancouver, Canada
2Jinan No. 7 Middle School, Jinan, Shandong, China
Since mulberry leaves are rich in alpha-glucosidase inhibiting ingredients, they have been widely used in the treatment of diabetes since ancient times. Microbial fermentation is an effective way to increase the content and efficacy of active ingredients in medicinal plants. In this paper, the beneficial endophytic bacteria in fresh mulberry leaves were used for solid state fermentation, and the effects of fermentation on flavonoid content and α-glucosidase inhibition in fresh mulberry were investigated. The results showed that the polysaccharide content of fresh mulberry leaves decreased rapidly during natural fermentation. The content of flavonoids in mulberry leaves decreased first and then increased. After 10 days of fermentation, the flavonoid content in mulberry leaves was 3.858±0.193mg/g dried ML, which was 2.14 times that of MLF in unfermented mulberry leaves. The alkaloid content increased significantly, reaching the highest value of 12.407±0.993 mg/g dried ML on day 8 of fermentation, which was about 2.5-folds higher than that of unfermented mulberry leaves. The inhibitory rate of the mulberry leaf extract (MLE8) fermented for 8 d was higher than that of the unfernented fresh mulberry extract (MLEU) when compared with that of α-glucosidase. At the concentration of 0.05mg/ml, the inhibitory rate of α-glucosidase from MLF-F8 increased to 82.7±4.15%while that from MLF-UF was only 66.8±3.34%.At the concentration of 5 μg/ml, the α-glucosidase inhibitory rate of MLA-F8 was 87.5±6.55%, while MLA-UF was only 71.4±5.57%.
Diabetes mellitus, Mulberry leaves, α-glucosidase inhibitors, solid-state fermentation, active compounds
Yidong Yin, Leran Yang. Changes in the Content and α-Glucosidase Inhibition Efficiency of Active Substance in Mulberry Leaves during Natural Fermentation. Academic Journal of Materials & Chemistry (2023) Vol. 4, Issue 7: 1-7. https://doi.org/10.25236/AJMC.2023.040701.
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