Phytochemical Studies And Antioxidant Properties Of Four Medicinal Plants Used In Cameroon

Four plants (Amphimas pterocaroides, Harungana madagascariensis, Myrianthus arboreus, and Cussonia barteri) that are commonly used in Cameroon for the management or reversal of anaemia were screened for their phytochemical content and antioxidant potential. Four extracts (methanolic, hydro-ethanolic, aqueous, and hydrolysed) from each of the plants were prepared and analysed. Qualitative phytochemical tests were used to detect the presence of alkaloids, tannins, saponins, flavonoids, glycosides and phenols, while three quantitative methods; Folin, Ferric Reducing Antioxidant Power (FRAP) and diphenyl -1, 2-picryl hydrazyl (DPPH) were used to determine the antioxidant potential of these extracts. With the exception of the extracts of Cussonia barteri (negative for triterpenes and phenols) and the aqueous extract of Harungana madagascariensis (negative result for cardiac glycosides and glycosides), all other extracts contained the phytochemicals tested. The highest antioxidant activities were observed in the hydrolysed extracts of each plant, while the aqueous extract showed the least activity irrespective of the method used. The presence of active phytochemical substances with antioxidant activities may provide substantial basis for the use of these plants in ethnomedicine. Keywords: Phytochemicals, Antioxidant, Folin, FRAP, DPPH.African Journal of Traditional and Complementary Medicine Vol. 4 (4) 2007: pp. 495-50

In vitro ion chelating, antioxidative mechanism of extracts from fruits and barks of tetrapleura tetraptera and their protective effects against fenton mediated toxicity of metal ions on liver homogenates

The aim of the present study was to investigate the antioxidant activity and protective potential of T. tetraptera extracts against ion toxicity. The antioxidant activity of the extracts was investigated spectrophotometrically against several radicals (1,1-diphenyl-2-picrylhydrazyl (DPPH•), 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS•), hydroxyl radical (HO•), and nitric oxide (NO•)), followed by the ferric reducing power, total phenols, flavonoid, and flavonol contents. The effects of the extracts on catalase (CAT), superoxide dismutase (SOD), and peroxidase activities were also determined using the standard methods as well as the polyphenol profile using HPLC. The results showed that the hydroethanolic extract of T. tetraptera (CFH) has the lowest ICvalue with the DPPH, ABTS, OH, and NO radicals. The same extract also exhibited the significantly higher level of total phenols (37.24 ± 2.00 CAE/g dried extract); flavonoids (11.36 ± 1.88 QE/g dried extract); and flavonols contents (3.95 ± 0.39 QE/g dried extract). The HPLC profile of T. tetraptera revealed that eugenol (958.81 ± 00 mg/g DW), quercetin (353.78 ± 00 mg/g DW), and rutin (210.54 ± 00 mg/g DW) were higher in the fruit than the bark extracts. In conclusion, extracts from T. tetraptera may act as a protector against oxidative mediated ion toxicity. © 2015 Bruno Moukette Moukette et al

Mexican sunflower (Tithonia diversifolia, Asteraceae) volatile oil as a selective inhibitor of Staphylococcus aureus nicotinate mononucleotide adenylyltransferase (NadD)

Tithonia diversifolia, well-known as Mexican sunflower, is an invasive shrub growing in tropical areas of South America, Asia and Africa where it is used as a traditional medicine, ornamental plant and green biomass to improve soil fertility. Given the traditional uses in the treatment of skin infections, we have first analysed the chemical composition and the antimicrobial effects of the essential oil hydrodistilled from inflorescences of T. diversifolia. For the purpose the inhibition zones against a panel of pathogens were measured by the agar diffusion method. In addition, we evaluated the inhibitory effects on several NaMN/NMN adenylyltransferases, which are essential enzymes for NAD biosynthesis in most bacterial pathogens, and also tested the inhibition on the mammalian orthologue enzymes as a promising way to identify novel natural antibiotics. To complete the screening of biological effects, the antioxidant capacity and antiproliferative effects on human tumor cells were evaluated using the DPPH, ABTS, FRAP, and MTT methods. Results showed that T. diversifolia essential oil was mostly active against Staphylococcus aureus with a halo of 14 mm. The essential oil selectively inhibited in vitro the pure NAD biosynthetic enzyme NadD from S. aureus (IC50 of ~60 μg/mL), with basically none or only minor effects on mammalian orthologue enzymes. Finally, the essential oil displayed significant cytotoxic effects on A375, MDA-MB 231, HCT 116 and T98G tumor cells with IC50 values of 3.02, 3.79, 3.46 and 12.82 μg/mL, respectively, and noticeable radical scavenging activity on DPPH and ABTS radicals, with IC50 values of 108.8 and 41.7 μg/mL, respectively

Diverse biological effects of the ajwain oil from Iranian Trachyspermum ammi

Trachyspermum ammi (Apiaceae) is a plant with a good reputation in the traditional Persian and Ajurvedic medicine. The hydrodistilled essential oil from the fruits of T. ammi, known as ‘ajwain oil’, is used in countries like Iraq, Iran, Afghanistan, Pakistan, and India in the preparation of curry, to flavor several foods, as preservative, and in perfumery. At therapeutic level, ajwain oil is employed in the treatment of gastrointestinal ailments, lack of appetite and bronchial problems. In the present work, the essential oil of T. ammi growing in Iran was analysed by GC-FID and GC-MS showing thymol (67.4%), p-cymene (17.9%) and γ-terpinene (11.3%) as the major constituents. Afterwards, we investigated the biological effects displayed by ajwain oil, namely the antimicrobial and antioxidant activity, the cytotoxicity on tumor cells, and the induction of lymphocyte proliferation. In addition, the inhibition on nicotinate mononucleotide adenylyltransferase (NadD), which is a promising new target for developing novel antibiotics, was evaluated. The antimicrobial effects of ajwain oil, measured by the agar disc diffusion method, were relevant, with inhibition zones higher than those of reference antibiotics, especially on S. aureus and C. albicans (34.7 and 54.3 mm, respectively). This effect was not due to the enzymatic inhibition on NadD. The ajwain oil exhibited a considerable dose-dependent inhibition on the ABTS radical cation, with an IC50 value of 22.4 µg/mL. MTT assay revealed that ajwain oil is particularly cytotoxic on colon carcinoma cells, with a IC50 value of 9.6 µg/mL. Finally, PBMC proliferation assay revealed some role for the ajwain oil within the network of interactions of the cells of the immune system