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The objective of this study was to perform phytochemical screening, estimate the total phenolics and flavonoids, and to evaluate the antioxidant potential of Tomborissa comorensis fruit. The dried and pulverized fruit of Tomborissa comorensis (150 g) were extracted exhaustively by the Soxhlet method with increasing polarity of solvents (hexane, ethyl acetate, and methanol). Folin–Ciocalteu reagent and aluminum chloride colorimetric methods were used to estimate the total phenolic and flavonoid content of the extracts. Three different methods, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power scavenging activity (FRAP), and total antioxidant capacity, were used to determine in vitro antioxidant activity. Phytochemical screening concerns the presence of flavonoids in the ethyl acetate and methanol extracts and tannins only on the methanol extract. The total phenolic and flavonoid content results show greater dominance in the methanol extract. All tests showed significant dose-dependent antioxidant activities. The ethyl acetate extract shows high activity in DPPH radical scavenging activity, but in a reducing power assay, it is the methanol extract that manifested high activity. The results of this study show that the fruit of T. comorensis is a rich source of phenolic compounds that can play an important role in preventing the progression of many diseases.

This study is planned to perform phytochemical screening, evaluate antioxidant activity and assess total phenolics and flavonoids content of methanolic and ethyl acetate extracts from the leaves of Stachys germanica subs cordigera briq. The dried powdered leaves of Stachys germanica subs cordigera briq (80 g) were extracted exhaustively by Soxhlet apparatus with increasing polarity of solvents (hexane, ethyl acetate and methanol). The total phenol and flavonoid contents in the methanolic and ethyl acetate extracts were determined by using the Folin-Ciocalteu reagent and aluminum chloride method, respectively. The antioxidant activities were examined by three different methods, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power scavenging activity (FRAP) and total antioxidant capacity. Phytochemical analysis of all extracts showed the presence of major classes of phytochemicals such as, flavonoids, tannins and polyphenols. Total phenolic and flavonoid contents results are showed in a large dominance in ethyl acetate extract. In vitro antioxidant activities of both extracts (ethyl acetate and methanol) were significant and ethyl acetate extract showed a higher potency than reference antioxidant Butylated Hydroxy Toluene (BHT) in total antioxidant capacity essay. It can be concluded that the crude extracts from the leaves of Stachys germanica subs cordigera briq. are a potential source of natural antioxidants which can be used in preventing the progression of many diseases.

The known flavonoid chrysin-7-O-(beta-D-glycopyranoside) (chrysin glucoside,1) as a major fraction and a new glycoside flavone, chrysin-7-O-beta-D-[(6"-acetyl)glycopyranoside] (2) were isolated from the flowers and leaves of Calycotome Villosa Subsp. Intermedia, They were identified by UV-Vis, 1R, (1)H-, (13)C-NMR and ESI-MS.