Derivatisation mechanistic-guided identification of phytoconstituents of different extracts of Cissus quadrangularis by TLC and standardization by HPTLC

•Antioxidant activity of four sequential extracts of Cissus quadrangularis (CQ) was performed and well explained by phytochemical screening.•First publication that described the in-depth analysis of CQ extracts using thin-layer chromatography, as well as potential detection pathways by derivatization.•Terpenoids, flavonoids, alkaloids, saponins, coumarin, steroidal and other phenolic phytoconstituents were found to be present in extracts of CQ.•Standardization was performed by HPTLC.•This study will be highly impacted in the phytochemicals screening of plant extracts by derivatization. Cissus quadrangularis is an indigenous medicinal herb which belongs to the family Vitaceae & commonly found in tropical and subtropical xeric wood. This plant is prescribed in the ancient Ayurvedic literature as a general tonic with excellent bone fracture healing properties. Different analytical approaches must be used to characterise the extracts to ascertain the therapeutic efficacy of different solvent-based plant extracts. Different extracts of Cissus quadrangularis (CQ) were screened by TLC, antioxidant activity and HPTLC. In the present study, the preliminary phytoconstituents’ analysis of sequential extracts of CQ; Petroleum ether extract (PECQ), Chloroform extract (ChCQ), Ethanol extract (EtCQ) and Water extract (WCQ) has been done by thin-layer chromatography (TLC). Additionally, the usage of derivative reagents and the reaction mechanism between derivative reagents and phytoconstituents were used to confirm the kind of phytoconstituents. The extracts were also evaluated by antioxidant activity that was accessed by the DPPH assay. The extract with the highest antioxidant activity was standardised by HPTLC. Terpenoids, flavonoids, alkaloids, saponins, coumarin, steroidal (phytoestrogen) and other phenolic/polyphenolic phytoconstituents were found to be present in extracts of Cissus quadrangularis. EtCQ showed the highest radical scavenging activity with an IC50 of 31.71±0.30 µg/ml which was significantly higher than PECQ, ChCQ and WCQ extract with an IC50 of 84.82±0.35 µg/ml, 79.16±0.35 µg/ml and 215.06±0.25 µg/ml respectively. EtCQ was standardized by HPTLC to quantify the marker constituent. This publication is the first to describe the in-depth analysis of Cissus quadrangularis extracts using thin-layer chromatography, as well as potential detection pathways using different reagents. TLC profiling also justifies the antioxidant behaviour of different extracts. [D