Phytochemical analysis and simultaneous quantification of solasodine and diosgenin content in different parts of Solanum xanthocarpum Schrad. & Wendl. by a validated high-performance thin-layer chromatography method

Abstract

Solanum xanthocarpum Schrad. & Wendl. (synonyms: Solanum virginianum L., Solanum surattense Burm.f.) (family: Solanaceae) is distributed throughout India in dry places as a weed, along roadsides and in wastelands. It is commonly known as yellow berried nightshade (English), kantkari (Sanskrit), bhatkatiya, kateli, choti kateli (Hindi). Traditionally, the species is described as pungent, bitter, digestive, alternative astringent, bitter and carminative. The root of S. xanthocarpum is the key ingredient of dashamula (ten roots) as depicted in Ayurveda and is also used as febrifuge, effective diuretic and expectorant [1]. Charaka and Sushruta used the extract of entire plant for bronchial asthma, dysuria and rejuvenation [2]. The different parts of S. xanthocarpum possess a wide range of biological activities such as antioxidant, hepatoprotective [3, 6], antibacterial [3], antiurolithiatic [4] and anti-HIV activity [5]. The fruit of S. xanthocarpum is a potential source of two medicinally and commercially important steroidal glycoalkaloid and sapogenin, i.e., solasodine and diosgenin [6, 7]. Other important chemical constituents from this species are solasonine, solamargine, caffeic acid, solanocarpidine, solanocarpine [8], lupeol, ursolic acid, campesterol, β-sitosterol, aesculetin, aesculin, campesterol, cycloartanol and daucosterol [9]. Solasodine is reported to have different biological—such as anti-fertility [10], anti-inflammatory, anticancer [11, 12]—activities and effects on the central nervous system [13]; diosgenin has a hypocholesterolemic effect, anticancer and antidiabetic activities [14, 15]. In the available literature, several high-performance thinlayer chromatography (HPTLC) methods are presented for the quantification of solasodine in different Solanum species and Ayurvedic formulations [16, 17]. However, the simultaneous quantification, isolation and characterization of solasodine and diosgenin were reported earlier only in the fruits of S. xanthocarpum [6]. Hence, the present study aims to develop a validated HPTLC method for the simultaneous quantification of solasodine and diosgenin in root, stem and fruit of S. xanthocarpum. The developed method is an efficient, quick, accurate and relatively inexpensive method of quantification, and thus eliminates the possible interference given by other structurally related compounds. This study will help in the standardization and regulation of batch to batch consistency in solasodineand diosgenin-containing raw material and/or formulations.