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The in vitro antioxidant and enzyme inhibitory activities of methanol and water extracts of Pseudevernia furfuracea (L) Zopf were evaluated. 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, cupric ion reducing (CUPRAC), metal chelating and phosphomolybdenum assays identified the methanol extract as superiority to the water extract. The water extract had the highest ferric reducing antioxidant power (FRAP) activity (105.97 mg trolox equivalents/g extract). The extracts showed weak inhibitory activity on cholinesterases. The water extract exhibited the highest tyrosinase inhibitory activity (7.46 mg kojic acid equivalent/g extract). The inhibitory activities of the methanol extract on α-amylase and α-glucosidase were 3.46 and 2.52 mmol acarbose equivalent/g extract respectively. The methanol extract was rich in both phenolic and flavonoid compounds. The methanol extract also contained considerable amounts of kaempferol and hesperidin. P. furfuracea was shown to be rich in polyunsaturated fatty acids. Among the polyunsaturated fatty acids, linoleic acid was the most abundant (27.87%).

The phytochemical composition, antioxidant and enzyme inhibitory activities of the ethanol and water extracts of Pyracantha coccinea were evaluated. Ethanol extract was found rich in phenolics, flavonoids, condensed tannins and saponins. Additionally, all the phytochemicals were found in higher amounts in ethanol extract except gallic, protocatechuic and trans-cinnamic acids. Ethanol extract had higher scavenging potential on DPPH radical, ABTS radical cation, superoxide anion and nitric oxide than the water extract. Ethanol extracts also exhibited higher activity in iron (III) to iron (II) reduction, cupric ion reducing, ferric reducing antioxidant power (FRAP) and phosphomolybdenum assays. On the other hand, activity of water extract was determined as 2.15 mg ethylenediaminetetraacetic acid equivalents (EDTAEs)/g fresh fruit in the chelating effect assay. Inhibitory activities of the extracts on acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase and tyrosinase were also analysed. In parallel to its phytochemical composition, ethanol extract showed better inhibitory activity on all enzymes tested.

The cytotoxic, anticholinesterase, antityrosinase and antioxidant effects of methanol extract from the flower of C. foetida subsp. rhoeadifolia (CFRME) were evaluated. The cytotoxic effect was investigated using HepG2, Caco-2, MCF-7 and MCF-10A cell lines. Enzyme inhibitory activities were tested by spectrophotometric methods. Different chemical assays were used to determine the antioxidant effects. In addition, phenolic constituents were quantified. High-performance liquid chromatographic (HPLC) analysis revealed that chlorogenic acid was the major phenolic component in the extract. The extract showed a strong antiproliferative, antioxidant, and anticholinesterase and antityrosinase effects. These findings suggest that C. foetida subsp. rhoeadifolia may be considered as a source of ingredients that can be used as food supplements.

The antioxidant and enzyme inhibitory potential of different solvent extracts (petroleum ether, ethyl acetate, methanol and water) from Sideritis galatica were evaluated. Cholinesterase, α-amylase and α-glucosidase inhibitory activities of the extracts were tested by microtiter plate assays. Antioxidant abilities were tested using free radical scavenging (DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid) and NO), reducing power (FRAP (ferric reducing antioxidant power) and CUPRAC (cupric reducing antioxidant capacity)), total antioxidant capacity and chelating assays. Methanol and water extracts showed higher phenolic content, DPPH and ABTS scavenging activity and reducing power activities, while the petroleum ether and ethyl acetate extract had the highest inhibition abilities on the enzymes. 18 phenolic components in these extracts were detected by using high performance liquid chromatography-diode array detector (HPLC-DAD). Results obtained in this work indicate that S. galatica may be useful as a source of natural agents for the management of oxidative process, Alzheimer's disease and type II diabetes.