Variation for caffeic acid and phenolic content in different plant parts of Solanum xanthocarpum Schrad. and Wendl. – a commercially important dashmool species

Abstract

Background: Environmental factors have profound effect on quantity vis-a-vis quality of phytochemicals in medicinal plants. Solanum xanthocarpum Schrad. and Wendl. is among the 10 dashmool species which is utilized in more than hundreds of Ayurvedic preparations including 'Dashmoolarishta'. Phenolics are the pharmacologically valuable compounds. Therefore, the present study was undertaken to assess the total phenolic (TP) and Caffeic acid (CA) contents in four different plant parts i.e., leaves, fruits, stem and roots of S. xanthocarpum sampled randomly from different locations of Madhya Pradesh, a central Indian state. Methods: Plant samples were collected from 99 places of 29 districts falling in 11 agroclimatic regions of Madhya Pradesh through random sampling. UV-VIS spectrophotometer and HPTLC were used to determine TP and CA contents, respectively. Phytochemical screening was carried out using standard methods. Results: Preliminary phytochemical screening indicates the presence of alkaloids, cardiac glycosides, flavonoids, phenols, steroids and terpenoids in all plant parts. Quantification of TP and CA contents revealed that both varied significantly between agroclimatic zones as well as within plant parts of S. xanthocarpum. Results revealed that among analysed plant parts, roots and stem harbored highest content of CA while fruits and leaves had the highest TP content. Among agroclimatic regions, accessions of Satpura plateau can be considered rich in CA and TP contents for fruits (0.030\%; 28.70 mg CE/g), leaves (0.058\%; 27.90 mg CE/g) and roots (0.161\%; 5.17 mg CE/g). For stem, highest CA (0.100\%) and TP (13.23 mg CE/g) contents were observed in samples of Malwa Plateau and Central Narmada Valley, respectively. Conclusion: We conclude that agroclimatic regions have significant effect on studied phytochemicals and Satpura plateau agroclimatic zone may be targeted for conservation and sustainable utilization of this valuable dashmool species if the target plant parts are fruits, leaves and roots. While, Malwa Plateau and Central Narmada Valley zones may be targeted for stem. Further, fruits and roots may be utilized for extraction of TP compounds and CA respectively.