Diospyros lycioides Desf:Review of its botany, medicinal uses,pharmacological activities and phytochemistry

Diospyros lycioides Desf.(D. lycioides) is traditionally used as herbal medicine against various human and animal ailments in tropical Africa. The present paper reviewed information on botany, medicinal uses, phytochemistry and pharmacological activities of D. lycioides. This review was compiled using scientific literature from electronic search engine such as PubMed,Scopus, ScienceDirect, Springerlink, BioMed Central, Scielo, Medline and Science domain.Additional literatures were obtained from book chapters, books, dissertations, websites and other scientific publications. D. lycioides is used as traditional medicine in 50% of the countries where the species is native in tropical Africa. This study recorded 22 medicinal uses of D.lycioides which included abdominal pains, infertility in women, sexually transmitted infections,and used as chewing sticks(or mouthwash), toothbrushes and ethnoveterinary medicine. D.lycioides extracts demonstrated anti-adhesive, anti-inflammatory, antimetastatic, antioxidant,antifungal, antiproliferative, mutagenicity and antibacterial activities. Future research should focus on the pharmacological properties, phytochemistry, clinical trials and pharmacokinetics of D. lycioides which will enhance the therapeutic potential of the species.

Phytochemical and antioxidant activities of Rumex crispus L. in treatment of gastrointestinal helminths in Eastern Cape Province, South Africa

Objective: To evaluate the antioxidant activities and phytochemical content of the leaf and root extracts of Rumex crispus using the solvents extraction; methanol extract,ethanol extract, acetone extract(ACE), and water extract.Methods: Total flavonoids content, total phenolic content, and total proanthocyanidin were evaluated using spectrophotometric equivalents of the standards, quercetin, gallic acid and catechin respectively. The antioxidant activities of the plant extracts were determined using ABTS, DPPH, ferric reducing antioxidant power, total antioxidant capacity and nitric oxide scavenging assays.Results: The flavonoids and phenols contents of the extracts were in the range of(19.39 ± 4.08) to(526.23 ± 17.52) mg QE/g and(16.95 ± 12.03) to(240.68 ± 3.50) mg GAE/g, respectively. ACE of the leaf has the highest value of total flavonoids content(526.23 ± 17.52) mg QE/g while ACE of the root has the highest value of total phenolic content(240.68 ± 3.50) mg GAE/g. The highest content of total proanthocyanidin(645.38 ± 1.33) mg CE/g was in ACE of the root. Significant amounts of saponin and alkaloid were also present in the root and leaf extracts. All solvent fractions showed significant antioxidant activities(P < 0.05) with ACE of the root having the highest scavenging value as shown in DPPH, ABTS, total antioxidant capacity, nitric oxide and ferric reducing antioxidant power(IC50= 0.014 mg/m L, <0.005 mg/m L, 0.048 mg/m L,0.067 mg/m L, and 0.075 mg/m L, respectively).Conclusions: In this study, the mean phytochemical content of the root of Rumex crispus is higher than that of the leaf and this may have contributed to its high antioxidant activities. This may also justify the frequent use of the root more than the leaves in traditional medicine for the cure of helminthic infections.

Phytochemical screening and in vitro evaluation of antioxidant and antimicrobial activities of Kedrostis africana(L.)Cogn

Objective: To investigate phytochemical, antioxidant and antimicrobial activities of Kedrostis africana(K. africana).Methods: Dried tubers of K. africana were extracted in acetone, water and ethanol. The total phenol, flavonoid, proanthocyanidin and tannin contents were determined spectrometrically. The antioxidant activity was examined using 2,2-diphenyl-1-picrylhydrazyl,2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt, nitric oxide and hydrogen peroxide assays. The antimicrobial activity was determined by agar dilution method using minimum inhibitory concentration against 3 g positive and three gram negative strains while four fungal strains were also investigated.Results: Total phenol, flavonoids, proanthocyanidin and tannin contents ranged from(5.32 ± 0.01) to(10.51 ± 0.01) mg GAE/g;(42.58 ± 0.02) to(529.23 ± 0.01) mg QE/g;(15.05 ± 0.00) to(585.64 ± 0.00) mg CE/g and(0.301 ± 0.010) to(0.937 ± 0.000) mg TAE/g, respectively. The IC_(50) values of the ethanol extract for 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and hydrogen peroxide were 0.054 and 0.057 mg/mL,respectively, aqueous extract had an IC_(50) value of 0.135 7 mg/mL for nitric oxide while the acetone extract had an IC_(50) value of 0.300 mg/mL for 2,2-diphenyl-1-picrylhydrazyl.The ethanol extract demonstrated effective antimicrobial activity against the tested pathogenic species with minimum inhibitory concentrations values ranging from 2.5–5.0 mg/mL for bacteria and(0.312 5–5.000 0) mg/mL for fungi, respectively.Conclusions: The tuber of K. africana showed potent free radical scavenging property and antimicrobial activity.

Cytotoxicity and effect of extraction methods on the chemical composition of essential oils of Moringa oleifera seeds

Renewed interest in natural materials as food flavors and preservatives has led to the search for suitable essential oils. Moringa oleifera seed essential oil was extracted by solvent-free microwave and hydrodistillation. This study assessed its chemical constituents. Cytotoxicity of the oils was investigated using hatchability and lethality tests on brine shrimps. A total of 16 and 26 compounds were isolated from the hydrodistillation extraction （HDE） and solvent-free microwave extraction （SME） oils, respectively, which accounted for 97.515% and 97.816% of total identifiable constituents, respectively. At 24 h when the most eggs had hatched, values of the SME （56.7%） and HDIE （60.0%） oils were significantly different （P〈0.05） from those of sea water （63.3%） and chloramphenicol （15.0%）. Larva lethality was different significantly （P〈0.05） between HDE and SME oils at different concentrations and incubation periods. The median lethal concentration （LC50） of the oils was 〉 1000 mg/ml recommended as an index for non-toxicity which gives the oil advantage over some antioxidant, antimicrobial, therapeutic, and preservative chemicals.

Evaluation of acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. in Wistar rats

Objective： This study investigated the acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. （AEVM） in rats for evaluating its safety profile. Methods： AEVM for the acute （2000 and 5000 mg/kg） and subacute （200, 400 and 600 mg/kg） toxicity studies was administered orally to rats according the guidelines 425 and 407 of Organization for Economic Cooperation and Development, respectively. Food and water intake as well as body and organ weight of animals were recorded. Signs of toxicity were assessed, and hematological, biochemical and histopathological analyses were performed. Results： In the acute toxicity study, a single dose of the aqueous extract at 2000 or 5000 mg/kg caused no mortality in the animals, suggesting that the median lethal dose is greater than 5000 mg/kg. In the subacute toxicity study, administration of the extract for 28 d, at all doses, caused no significant changes in the body weights or organ weights of rats in the treated groups when compared with the control group. In addition, hematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological sections of the heart, liver and kidney from test animals showed no signs of degen- eration. Conclusion： These results showed that AEVM at dosage levels up to 600 mg/kg is nontoxic and could also offer protection on some body tissues. AEVM could, therefore, be considered safe.