Phytochemicals and in vitro antioxidant potentials of defatted methanolic extract ofHolarrhena floribunda leaves

Plant-based dietary components and additives are known to protect cells from deleterious effect of reactive oxygen species (ROS). Proximate, phytochemical and antioxidant potentials of methanolic extract of defatted Holarrhena floribunda (G.Don) leaves were assessed using in vitro systems such as, 1,1 diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, nitric oxide radical scavenging and inhibition of lipid peroxidation. Total antioxidant activity was measured using phosphomolybdenummethod. Total phenol content and the reductive potential of the extract were also evaluated. The results of the proximate analysis revealed that the leaf contained 0.23% moisture, 12.8% ash, 9.62% crude fat, 23.3% crude fibre, 21.17% protein and 32.68% carbohydrate while the phytochemical constituents included alkaloid, saponin, tannin and cardiac glycosides. The leaf extract of H. floribunda (G. Don) exhibited scavenging activity with IC50 of 12.63, 1,377.00 and 244.00 ìg/ml for DPPH, hydroxyl radical and nitric oxide radical respectively. The extract conferred 50% protection at the concentration of 73.80 ìg/ml on lipid peroxidation induced by FeSO4 in egg yolk. Total antioxidant capacity equivalent of gallicacid and vitamin C were 195.57 and 519.28 g/mg of extract respectively and total phenol content equivalent of gallic acid was 1427.87 ìg/mg. The reductive potential increased with increasing concentration of extract. The results obtained from this study reveal that the extract is rich inantioxidant components with several mechanisms of eliciting antioxidant actions which provide scientific basis for its use in folk medicine

Effect of stem - bark ofErythrophleum suaveolens (Guill. & Perri.) saponin on fresh water snail (Lanistes lybicus) tissues

The study investigated the activity of saponin from ethanolic extract of Erythrophleum suaveolens stem bark against freshwater snail, Lanistes lybicus. The crude saponin (4 g) was separated by silica gel using gradient elution with dichloromethane in methanol (100:0 to 0:100) followed by thin layer chromatography using precoated silica gel 60 F254. Fractionated saponins (90:10, 80:20 and 70:30) were employed for snail toxicity using fresh water snails, L. lybicus. The biochemical changes were evaluated in haemolymph, muscle, intestine and hepatopancreas of fresh water snails exposed to sublethal dose of fractionated saponins. Elevation of activities of acid and alkaline phosphatase in the intestine and hepatopancreas, haemolymph and total protein level were observed. The activity ofacetylcholinesterase was inhibited in the haemolymph, muscle, hepatopancreas and intestine of the snails. The activity of saponin was observed to be dose dependent as mortality increased with relativeincrease in the saponin concentrations. The study provides considerable scope in exploiting local indigenous plant resources for control of fresh water snails and monitor water pollution.Key words: Erythrophleum suaveolens, saponin, molluscicidal activity, Lanistes lybicus, pollution, hepatopancreas

Biological activities (anti-inflammatory and anti-oxidant) of fractions and methanolic extract of Philonotis hastate (Duby Wijk & MargaDant).

Background: Bryophytes like other lower plants (non-vascular plants) are not traditionally employed for therapeutic purposes. Hence this study evaluated the in vitro anti-oxidant potentials and anti-inflammatory activities of the fractions and methanolic extract of Moss (Philonotis hastata, Duby) with a view to studying its biological activities.Methods: Plant materials were collected, identified, dried, pulverized and extracted with 70% (v/v) methanol to afford methanolic extract (ME). The ME was fractionated using solvent of increasing polarity and followed by phytochemical screening of the extract and fractions. The anti-oxidant potentials (total phenolics and flavonoids), anti-oxidant activities (DPPH-radical scavenging, reductive power, hydroxyl radical scavenging and ABTS+ radical scavenging) and anti-inflammatory activity (red blood stabilizing) of the extract and fractions were investigated.Results: Phytochemicals detected included alkaloids, steroids and cardiac glycosides. The fractions and methanolic extract exhibited moderate antioxidant potentials with various models. The flavonoid contents of the methanol extract and fractions ranged between 1.70 ± 0.05 and 129.70 ± 1.00 mg/g extract RE (Rutin Equivalent) and total phenol content ranged between 1.84 ± 0.62 and 136.25 ± 0.18 mg/g extract TAE (Tannic Acid Equivalent). The reductive power activity ranged between 5.71 ± 0.02 and 40.40 ± 0.30 mg/g Vitamin C equivalent, the hydroxyl radical scavenging (15.54 ± 0.02 to 30.07± 0.29 %), and the ABTS+- radical scavenging activity (11.59 ± 2.85 to 40.50 ± 1.35%). The membrane stabilizing potentials of the fractions and extract (methanol) ranged between 19.19 ± 2.66% and 78.26 ± 2.60%. The activities were comparable to standard antiinflammatory drugs and chemicals.Conclusion: It could be concluded that the fractions and methanol extract of P. hastata exhibit moderate, potent and appreciable anti-oxidant and anti-inflammatory activities with aqueous and ethyl acetate fractions elicited highest activities. As such, bryophytes possess therapeutic potentials and could be employed in the treatment and management of anti-oxidant and anti-inflammatory disorders.Key words: Philonotis hastata, bryophytes, membrane - stabilizing, flavonoids, anti-oxidant, anti-inflammatory

Toxicity of Erythrophleum guineense stem-bark: role of alkaloidal fraction

The effect of the in vivo administration of the total alkaloidal fractions of the stem-bark of the Erythropleum guineense on certain biological parameters of Sprague-Dawley rats was investigated. The results revealed that plasma alanine aminotransferase activity, liver aspartate aminotransferase activity, liver glycogen, liver protein, creatinine and haemoglobin concentrations were reduced while plasma aspartate aminotransferase activity, liver alanine aminotransferase activity, plasma urea concentration, bilirubin concentration and alkaline phosphatase activity were elevated in Sprague -Dawley rats treated with total alkaloidal fractions of E. guineense stem-bark. The phytochemical assays revealed that the chemical composition of E. guineense include alkaloids, saponins, cardiac glycosides and tannins. The toxicity of the stem-bark of E. guineense could be attributed to the combined toxicity of other constituents such as tannins, saponins and glycosides with the alkaloids as earlier speculated. Key Words: Toxicity, hepatic, Erythrophelum guineese, alkaloidal fraction, aminotransferases, alkaline phosphatase. Afr. J. Trad. CAM (2004) 1: 45-5

Bioactivity-guided evaluation of the root extract of Plumbago zeylanica

The haemagglutination, free radical scavenging and membrane stabilizing activities of combined ethyl acetate/diethylether extract of root of Plumbago zeylanica were investigated. The combined fraction (ethyl acetate/diethylether) was chromatographed on silica gel column using hexane/ethyl acetate gradient elution (100:0 – 0:100 v/v) to afford seven fractions (A-F) based on Rf values and phytochemical evaluation tests. The fractions were assayed for phytochemical constituents, total phenol contents, free radical scavenging and membrane stabilizing activities and toxicity using haemaglutination assay method. The phytoconstituents include anthraquinones, flavonoids and phenolic acids. The phenolic contents in the fractions ranged between 0.27 ± 0.04 and 0.93 ± 0.28 mg/g tannic acid equivalent (TAE). The fractions exhibited strong and appreciable free radical scavenging and membrane stabilizing activities and agglutinated red blood cells, which implied toxicity. These activities compared favourably with standard anti-inflammatory and anti-oxidant drugs. The results revealed that while some of the fractions haemaglutinated red blood cells, others provided effective antioxidant and anti-inflammatory activities