Red Clover (<i>Trifolium pratense</i> L.) Sprout Prevents Metabolic Syndrome

Abstract

We examined the prevention effect of red clover (Trifolium pratense L.) sprout on metabolic syndrome using a high-carbohydrate and high-fat diet (Western diet; WD)induced male C57BL/6J obese model mouse. Red clover sprout-lyophilized powder (RC) contained 3.5 mg/g dry-weight of formononetin as a major phenolic compound, as analyzed by high performance liquid chromatography. Supplementation of 0.3% (w/w) RC in a WD (WD1RC) showed an anti-obesity effect and ameliorated lipid metabolism in the obese model mice. Additionally, fasting plasma glucose levels were significantly reduced in the WD1RC group. Administration of 0.1 mg/kg formononetin reduced the postprandial blood glucose level, as assessed using the oral maltose tolerance test. However, no significant formononetin intake effect was observed on the plasma insulin level. These results suggest that the formononetin contained in red clover sprout inhibits a-glucosidase and thereby contributes to reducing the postprandial blood glucose response in mice.

Perspectives on the Combined Effects of Ocimum basilicum and Trifolium pratense Extracts in Terms of Phytochemical Profile and Pharmacological Effects

“…Figure 2 shown the Trifolium species that contain amounts of isoflavones in descending order. Among the Trifolium species the richest in isoflavones is T. pratense [ 27 , 31 , 32 ].…”

Red Clover Isoflavones Influence Estradiol Concentration, Exercise Performance, and Gut Microbiota in Female Mice

“…In recent years, RC has been used in ameliorating menopausal symptoms, such as hot flush, night sweats, urogenital atrophy, depression, and anxiety, in postmenopausal women (6). In addition, RC can contribute to postprandial blood glucose level reduction, improves hypoglycemia, is an antioxidant, and has effects against obesity in a rat model (7) and osteoporosis in postmenopausal women (3,(7)(8)(9)(10).…”

Effects of isoflavone‐rich red clover extract on blood glucose level: A randomized, double‐blind, placebo‐controlled trial

“…The RC extract was prepared by Oryza Oil & Fat Chemical Co. Ltd (Aichi, Japan) by extraction from RC sprouts using a 90% ethanol solution equivalent to five times the weight of the raw material, at 60 °C for 2 hr. The 1.91 g of RC extract contained 8 mg formononetin and 1.8 mg biochanin A, an amount calculated as the human equivalent dose (in a previous study that used 0.3 % [w/w] lyophilized RC‐sprout powder containing those isoflavones for mice; Yokoyama et al., 2020). The ingredients of RC extract are shown in Table 1.…”

“…As with other legumes, RC is rich in isoflavones with various beneficial health effects, most notably for menopausal symptoms (Ghazanfarpour et al., 2016; Kanadys et al., 2020). RC sprouts have been reported to be rich in formononetin as their major isoflavone and second in biochanin A (Yokoyama et al., 2020). Formononetin and biochanin A are potent α‐glucosidase (also called maltase) inhibitors, which block α‐glucosidase from hydrolyzing the α‐1,4‐glucosidic bond (Jiang et al., 2015; Yuk et al., 2011).…”

“…The inhibitory effects of those isoflavones for α‐glucosidase are considered to suppress sugar absorption, and thus decrease blood glucose levels (Gong et al., 2020). A study of oral maltose tolerance test (OMTT) in obese mice showed that supplementation of those isoflavones (as lyophilized RC‐sprout powder) suppressed the increase in postprandial blood glucose, in addition to body weight, and adipose tissue weight (Yokoyama et al., 2020). However, whether suppressive effect of those isoflavones on blood glucose applies to humans is unclear.…”