Comprehensive evaluation of phytoestrogen accumulation in plants and in vitro cultures of Medicago sativa L. ‘Elçi’ and natural tetraploid Trifolium pratense L.

Abstract

IntroductionHigher plants synthesize a wide variety of phenolic compounds during their regular growth and development. These phenolic compounds are products of the phenylpropanoid biosynthetic pathway and generally accumulate at relatively high concentrations in cell vacuoles, and they are usually chemically associated with sugars (Coronado et al., 1995). Flavonoids are found throughout the plant kingdom, whereas isoflavones are more restricted and particularly prevalent in the subfamily Papilionoideae of Fabaceae.The Fabaceae taxonomic class includes a variety of plants with significant economic value, including soybean, alfalfa, clover, pea, and various beans. These leguminous plants accumulate a wide range of phenolic secondary compounds, including isoflavonoid conjugates (Kessmann et al., 1990b). An important group of legume natural products, isoflavones, have been better understood at the molecular genetic level (Dixon et al., 1995;Dixon 1999;Dixon et al., 2004). These compounds function as preformed or inducible antimicrobial, antiinsecticidal compounds, signaling molecules in symbiotic nodulation by Rhizobium bacteria, or as allelopathic agents. In vitro cultures, which are a key method for secondary metabolite production, have been established for some of the legumes. Cell suspension cultures of Glycine max contained higher amounts of total isoflavones than that of the callus cultures (Federici et al., 2003). Genistein, daidzein, formononetin, and biochanin A were observed in the cell suspension cultures of Medicago truncatula (barrel medic), which is the model legume in plant functional genomics (Suzuki et al., 2005;Farag et al., 2007). T. pratense, usually called red clover, has a variety of isoflavones, including biochanin A, genistein, daidzein, and formononetin, which were reported in high concentrations (Setchell et al., 2001;Khaosaad et al., 2008). Isoflavones may act as an estrogen agonist or antagonist, depending on the compound and content present in the organism (Dog, 2005). Thus, red clover has become popular as a food supplement for the amelioration of menopausal disorders (Dornstauder et al., 2001;Beck et al., 2003). Although red clover blossoms have been used in traditional herbal medicine for centuries, it is the semipurified isoflavone leaf extracts for relief of menopause-related symptoms that interest

Phytochemical Composition of Different Red Clover Genotypes Based on Plant Part and Genetic Traits

“…In this study, concentrations of formononetin were in ranges of 0.22–4.68 mg/g, 0–0.95 mg/g and 0.10–1.54 mg/g in leaves, flowers and stems, respectively, while these values for biochanin A were 0.59–5.94 mg/g, 0.17–1.52 mg/g and 0.08–0.56 mg/g ( Table 2 ). These ranges correspond with several published results [ 5 , 23 , 32 , 33 , 36 , 37 ]. Still, higher values are also observed and can go up to 28.5 mg/g for formononetin [ 38 ] and 17.9 mg/g for biochanin A [ 7 ].…”

“…The content of these compounds varies greatly depending on different factors. However, the majority of studies found that formononetin and biochanin A are the dominant isoflavones in red clover [ 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ]. In this study, concentrations of formononetin were in ranges of 0.22–4.68 mg/g, 0–0.95 mg/g and 0.10–1.54 mg/g in leaves, flowers and stems, respectively, while these values for biochanin A were 0.59–5.94 mg/g, 0.17–1.52 mg/g and 0.08–0.56 mg/g ( Table 2 ).…”

“…Also, it was established that leaves contain the highest concentration of isoflavones, which corroborates with the results of this study ( Table 2 ). Concerning other plant parts, in a few studies, it is reported that flowers contain the lowest concentration of isoflavones [ 7 , 23 , 33 , 37 ]. On the other hand, a study published by Butkutė et al (2014) showed that stems had the highest total isoflavone concentrations (over 4.5 mg/g) among aerial plant parts.…”

Silver nanoparticles production mediated by natural tetraploid Trifolium pratense L.: Characterization and potential biological activity

“…e natural tetraploid T. pratense L. (red clover) chromosome number is 2n = 4x = 28 (Buyukkartal & Colgecen, 2007). e natural tetraploid T. pratense L. variety contains more secondary metabolites than the diploid variety of the plant (Çölgeçen et al, 2014;Khaosaad et al, 2008). Its phytoestrogenic activity is very high mostly due to its content of isoflavones, which can act as estrogen agonists or antagonists, depending on the compound and its content in the body (Dog, 2005).…”

Formononetin Production by Large-Scale Cell Suspension Cultures of Medicago sativa L.

“…Medicago is also known as a model plant because of its ability to regenerate in vitro in plant tissue culture (Erişen, 2006). M. sativa is also reported to reduce the menopausal symptoms in women by increasing the levels of estrogen (Gülen, 2013;Çölgeçen et al, 2014;Franciscis et al, 2019). M. sativa is rich in flavonoids, too.…”