Saponins are a class of glycosides whose aglycones can be either triterpenes or helical spirostanes. It is commonly recognized that these active ingredients are widely found in various kinds of advanced plants. Rare saponins, a special type of the saponins class, are able to enhance bidirectional immune regulation and memory, and have anti-lipid oxidation, anticancer, and antifatigue capabilities, but they are infrequent in nature. Moreover, the in vivo absorption rate of saponins is exceedingly low, which restricts their functions. Under such circumstances, the biotransformation of these ingredients from normal saponins—which are not be easily adsorbed by human bodies—is preferred nowadays. This process has multiple advantages, including strong specificity, mild conditions, and fewer byproducts. In this paper, the biotransformation of natural saponins—such as ginsenoside, gypenoside, glycyrrhizin, saikosaponin, dioscin, timosaponin, astragaloside and ardipusilloside—through microorganisms (Aspergillus sp., lactic acid bacteria, bacilli, and intestinal microbes) will be reviewed and prospected.
Clinically, Chaenomeles sinensis (Thouin) Koehne (C. sinensis) has been used to treat hyperuricemia and gout. However, the exact mechanism of action is still unknown. In the present study, the ethyl acetate fraction of C. sinensis fruit extract (CSF-E) was separated. Potassium oxonate (PO)-induced hyperuricemic mice and normal mice were administered with CSF-E at 60, 120 and 180 mg kg−1, respectively for 7 days. Serum uric acid, creatinine and BUN levels, liver oxidative damage, and serum and hepatic XOD activities were primarily measured using assay kits. The evaluation of its nephroprotective effects was carried out by renal histopathological analysis. Simultaneously, renal protein levels of organic anion transporters, such as mURAT1 and mOAT1, were detected using western blotting to elucidate the possible mechanisms. The results showed that CSF-E could significantly inhibit XOD activities in both serum and liver (p < 0.05), decreasing uric acid, creatinine and BUN levels in serum, and increasing levels in the excretion of uric acid by down-regulated of mURAT1 and up-regulated mOAT1 protein expression of kidney in hyperuricemic mice. Moreover, PO-induced alterations in the levels of MDA, hepatic SOD and GSH-Px activities and renal inflammation damage in hyperuricemic mice were effectively recovered by CSF-E at 120 mg kg−1. CSF-E possessed anti-hyperuricemic and nephroprotective effects by suppressing XOD activity, improving renal function and regulating renal mURAT1 and mOAT1 protein expression, which resulted in beneficial effects on hyperuricemia and gout prevention.
Rice is a globally important staple consumed by billions of people, and recently there has been considerable interest in promoting the consumption of wholegrain brown rice (WBR) due to its obvious advantages over polished rice in metabolically protective activities. This work highlights the effects of innovative processing technologies on the quality and functional properties of WBR in comparison with traditional approaches; and it is aimed at establishing a quantitative and/or qualitative link between physicochemical changes and high-efficient processing methods. Compared with thermal treatments, applications of innovative nonthermal techniques, such as high hydrostatic pressure (HHP), pulsed electric fields (PEF), ultrasound and cold plasma, are not limited to modifying physicochemical properties of WBR grains, since improvements in nutritional and functional components as well as a reduction in anti-nutritional factors can also be achieved through inducing related biochemical transformation. Much information about processing methods and parameters which influence WBR quality changes has been obtained, but simultaneously achieving the product stabilization and functionality of processed WBR grains requires a comprehensive evaluation of all the quality changes induced by different processing procedures as well as quantitative insights into the relationship between the changes and processing variables.