Studies of In vitro Antioxidant and Cytotoxic Activities of Extracts and Isolated Compounds from Parinari curatellifolia (Chrysobalanaceae)

Parinari curatellifolia (family: chrysobalanaceae) is a plant used in Nigerian folk medicine for treatment of cancer and other diseases. In our search for pharmacologically active compounds, we have isolated and characterized compounds through column chromatography and spectroscopic techniques (MS, NMR and IR). We have evaluated the in vitro antioxidant activity of the different extracts and the pure compounds using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical model. The in vitro cytotoxic activity of the extracts and the pure compounds using the sodium 3’-[1-(phenylamino-carbonyl) -3,4-tetrazolium]-bis-[4-methoxy-6-nitro] benzene sulfonic acid hydrate (XTT) colorimetric method on cervical cancer (HeLa) cell line have also been assessed. The extracts and pure compounds have displayed moderate to excellent antioxidant and cytotoxic activities.  The biological results suggest that these compounds may be suitable candidates for further drug development and investigation. The results obtained have provided a promising scientific basis for the use of P. curatellifolia in traditional medicine for treatment of cancer. Keywords: Parinari curatellifolia, Cytotoxicity, HeLa Cell line, Antioxidant, DPPH Free Radica

Isolation and Characterization of Triterpenes from Petroleum Ether and Ethyl acetate Extracts of Stem Bark of Parinari curatellifolia Planch Ex. Benth (Chrysobalanaceae)

Parinari curatellifolia (Chrysobalanaceae) is a plant used in Nigerian folk medicine for cancer treatment. Through series column chromatography, betulin (lup-20(29)-en-3?,28-diol) and betulinic acid (3?-hydroxy-lup-20(29)-en-28-oic acid) have been isolated from petroleum ether and ethyl acetate extracts of the stem bark of Parinari curatellifolia respectively. The compounds were characterized on the basis of 1D-NMR (1HNMR, 13CNMR and DEPT-45, 90 and 135), 2D-NMR (HSQC, HMBC, 1H-1H COSY,  1H-1H NOESY), MS and IR spectroscopic studies. These two compounds are reported for the first time as constituents in Parinari curatellifolia. Key words: Parinari curatellifolia, Chrysobalanaceae, Betulin, Betulinic acid and Triterpene

Development of Quality Standards of Prosopis africana (Guill. & Perr.) Taub. Stem Bark

Prosopis africana (Guill. & Perr.) Taub. (Mimosoidae) is the only known species of its genus found in Africa. Almost all parts of the tree are used in medicine. Remedies for skin diseases, caries, fevers and eye washes are obtained from the bark. They are used as diuretic and for the treatment of gonorrhoea, tooth and stomach-ache, dysentery and bronchitis. It is therefore considered worthwhile to establish quality standard for the stem bark. Pharmacognostic standardization was carried out on the pulverized stem bark and its anatomical section, to determine the macro and micro morphological characters, quantitative and qualitative profiles. The results of this study produced vital data that could be useful in setting some diagnostic indices for the identification and preparation of a monograph of the plant stem bark. Keywords: Prosopis africana, anatomical indices, physicochemical, morphological characters, microscopical,  macroscopica

A Friedelane Type Triterpene From Prosopis africana (Guill. & Perr.) Taub. Stem Bark

Prosopis Africana can be found growing wild in Northern and the Middle Belt of Nigeria and it is the only known species of its genus found in Africa. In folk medicine, the stem bark is used as remedies for skin diseases, caries, fevers gonorrhoea, tooth and stomach-ache, dysentery and bronchitis. Chemical investigation of the stem bark resulted in isolation and characterisation of a friedelane type triterpene, compound J29. J29 was isolated by column chromatography from the chloroform fraction of ethylacetate extract. The J29 1H-NMR 13C-NMR and DEPT135 spectra matched the characteristic data of the proposed triterpene skeleton. The compound was finally identified as friedelin on the basis of spectroscopic evidence, including 2D NMR as well as its IR spectrum. Friedelin is being reported for the first time as a chemical constituent of P. africana. Keywords: Prosopis africana, friedelane type, phytochemical constituents, spectroscopy, chromatograp

Isolation and Characterization of Anti-inflammatory Compound from Ocimum gratissimum Leaves Extract

The study was undertaken to identify the possible bioactive compound responsible for the anti- agent in Nigerian traditional medicine. Thin layer chromatographic profile of the extract was determined using appropriate solvent system. The compound isolated had a percentage yield of 33.3% and corresponding Rf value of 0.78 with characteristic aromatic, reddish-brown, oily appearance. Paper and Sudan III tests gave positive test for oil. Subsequent isolation and characterization of the purified compound using column chromatography, alpha-D determination and spectroscopic techniques (UV, IR, NMR and MS) led to the discovery of the proposed compound: methyl-octadeca-9, 12-dienoate also known as methyl linoleate. An increase in the rats hind paw diameters induced by sub-planter injection of a phlogistic agent (formalin 0.1 mL/kg of 2.5 %) was used as a measure of acute inflammation. Ethyl acetate extract was found to have a significant (P <0.01) inhibitory effect on the formalin-induced oedema in rats at the doses of 50, 100, and 200mg/kg body weight (orally) tested in rats when compared to the normal saline (negative control). The extract also competed significantly (p<0.05) and favourably with standard drug, prednisolone (positive control) at 10 mg/kg body weight. The results confirmed that ethyl acetate extract contains bioactive compound which maybe responsible for the anti-inflammatory activity of the plant’s leaves and is probably the reasons for the widespread use of the plant as anti-inflammatory agent locally and in Nigerian traditional medicin

Comparative Phytochemical Screening and Antibacterial Activity of Tapinanthus globiferus (Mistletoe) Growing on Azadirachta indica, Olea europaea and Albezia chevelleri

Tapinanthus globiferus is mistletoe which grows on many plants. Mistletoes have been used in traditional medicine for treatment of diseases. Their extracts have been reported to demonstrated potent biological activities. Tapinanthus globiferus from Azadirachta indica, Olea europaea and Albezia chevelleri were extracted with the aid of a soxhlet extractor using n-hexane and methanol. The extracts were screened for the presence of phytochemicals using standard procedures. The antibacterial activity of the extracts were evaluated against gram positive (S. aureus and B. subtillis) and Gram negative (E. coli and P. aeruginosa) bacterial isolates using agar diffusion method. The preliminary phytochemical screening revealed the presence of saponins, tannins, flavonoids and cardiac glycosides in all the three samples. Anthraquinones were absent in all three samples. Alkaloid was found to be present in Tapinanthus gloiferus growing on Azadirachta indica. The susceptibility test of the methanol extracts showed zone of inhibition with the range of 8-20 mm. The hexane extracts did not show any activity. The result of the MIC (minimum inhibition concentration) of the methanol extract was 7.5 mg/mL and the MBC (minimum bactericidal concentration) was 15 mg/mL. The result of this study indicates a little difference in the chemical composition of various Tapinanthus globiferus growing on each of the plants. This may be attributed to the fact that the chemistry Tapinanthus globiferus depends on the host plant. Since they grow on different host plants, they may contain slightly different chemical constituents. The antibacterial activity demonstrated may be due to the presence of these phyochemicals

Phytochemical studies and elemental analysis of the root bark of Piliostigma thonningii(Schum.) obtained in Sokoto

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Isolation and Characterization of Di-(2-ethylhexyl) Phthalate from the Leaves of Combretum micranthum (Altum) Combretaceae

Combretum micranthum is a medicinal plant used in traditional medicine for treatment of wounds, sores, diarrhoea, pain, fever and skin infections. This study was aimed at isolation and characterization of compounds from the leaves of Combretum micranthum. The pulverized leaves of the plant were gradiently extracted with hexane, ethyl acetate and methanol using soxhlet apparatus. The isolation of the compound was done using silica gel gravity column chromatography and preparative thin layer chromatography which yielded yellow compound ‘A’. The characterization of the isolated compound was carried out using 13C-NMR, 1H-NMR and GC-MS. Data obtained from the spectral analyses, suggested the compound to be di-(2-ethylhexyl) phthalate