Pro- and Antioxidant Effects and Cytoprotective Potentials of Nine Edible Vegetables in Southwest Nigeria

Facile biosynthesis, characterisation and biotechnological application of ZnO nanoparticles mediated by leaves of Cnidoscolus aconitifolius

The present study synthesised and characterised zinc oxide nanoparticles (ZnO NPs) using spinach tree, Cnidoscolus aconitifolius and investigated its potential use as nanofertilizer. The synthesised nanoparticles showed UV-Vis absorption peak at 378 nm which is a feature of ZnO NPs. FT-IR analysis further revealed the presence of O-H stretching, C = C bending, O-H bending and C-N stretching functional groups of the stabilising action of the plant extract on the surface of the nanoparticles. SEM images displayed the shape of NPs to be spherical whereas TEM images showed their distribution sizes to be 100 nm. Synthesised ZnO NPs were used as a nano fertilizer on Sorghum bicolour plant. An increase in the shoot leaf length with an average length of 16.13 ± 0.19 cm as compared to the control group of 15.13 ± 0.07 cm was observed. The rate of photosynthesis also showed a significant increase with total chlorophyll content of 0.2806 ± 0.006 mg/mL as compared with control of 0.2476 ± 0.002 mg/mL. The activity of antioxidative enzymes was measured with an increase in the specific activity of SOD in the plant when ZnO NPs were used over NPK whereas, the specific activities of CAT were similar in all cases.

Toxicity assessment of the methanol extract of Jatropha tanjorensis (Euphorbiaceae) leaves

Background

The leaves of Jatropha tanjorensis have been found to have important application both in traditional medicine and as an edible vegetable in Nigerian soups. It is popularly employed in Nigeria for the treatment of anemia, diabetes, and malaria. The dearth of information on its toxicity prompted this study. Mice were administered single oral doses of 10, 100, 1000, 1600, 2900, and 5000 mg/kg b.wt (n = 3/group) of the extract and were observed for 24 h for any sign of toxicity and mortality in the acute toxicity study. For the sub-acute toxicity study, doses of 100, 200, and 400 mg/kg b.wt of the extract were administered to experimental rats (n = 6/group) for 28 days after which the assessment of hematological and biochemical parameters, as well as liver and kidney histology was conducted post-treatment. Body weight of the animals was also taken weekly.

Results

The result showed that percentage weight gain decreased as the dose of extract increased. The haematological and biochemical parameters showed that the extract had no toxic effect on experimental animals, though there was a non-significant dose-dependent decrease in WBC. The extract also showed potential to cause hepatotoxicity at the highest dose.

Conclusion

Though the median lethal dose of the plant extract suggests relative safety of the plant material, consuming large amounts over a prolonged time may need to be discouraged to avoid potential damage to vital organs such as the liver.

Functional and sensory properties of jam with different proportions of pineapple, cucumber, and Jatropha leaf

Introduction. Fruits and vegetables are vital for healthy food consumption. Conservation is the only option to prolong their shelf life. Nigeria is currently experiencing an increase in production of fruit jams that incorporate vegetables. Cucumbers, Jatropha tanjorensis L. leaf, and pineapples have a lot of health benefits, which makes them very promising for jam making. The present research featured the effect of cucumber, pineapple, and Jatropha leaf in different proportions on the functional and sensory properties of composite jam. Study objects and methods. The technology of jam making followed standard procedures. Pineapple jam without cucumbers and Jatropha leaf served as control (pineapple:cucumber:Jatropha leaf = 100:0:0). The experimental jam samples had increasing amounts of Jatropha leaf (J), decreasing amounts of pineapple pulps (P), and a constant amount of cucumber (C), i.e. P:C:J = 85:10:5, 80:10:10, 75:10:15, and 70:10:20. The functional analysis involved chemical and proximate aspects, whereas the sensory evaluation involved appearance, aroma, taste, spreadability, and overall liking. Results and discussion. The experimental samples showed a significant difference (P < 0.05) in vitamins, minerals, total titratable acidity, pH, Brix, and total soluble solids. The control sample (P:C:J = 100:0:0) had significantly lower (P < 0.05) contents of moisture, protein, ash, fat, and fiber than the experimental ones. However, the pH and total titratable acidity of the experimental samples 85:10:5 and 80:10:10 appeared to be quite similar (P > 0.05). Compared to the control sample, the sensory properties of the experimental samples differed significantly (P < 0.05) by appearance, aroma, and spreadability but were of similar (P > 0.05) taste and overall liking. Conclusion. The obtained functional and sensory data proved that the new pineapple jam with cucumber and Jatropha leaf is a promising functional product.

Antioxidant Activities of Methanol Extracts of Thirteen Cameroonian Antibacterial Dietary Plants

This study falls within the search for alternative solutions to problems related to diseases associated with oxidative stress. It involved the evaluation of antioxidant activities extracts from thirteen antibacterial Cameroonian food plants, namely, P. nigrum, A. cruentus, L. sativa, S. edule, S. nigrum, V. amygdalina, A. hybridus, V. hymenolepis, L. capensis, M. esculenta, C. melo, T. occidentalis, and T. triangulare. The thirteen plant extracts with a broad spectrum of antibacterial activity all showed total reducing powers ranging between 2.41 and 27.81 AAE (mg ascorbic acid equivalents per gram of dried extract) and total phenol contents between 2.65 and 35.03 GAE (mg of gallic acid equivalents per gram of dried extract) of dry extract. Except for extracts of L. capensis, the other 12 extracts showed flavonoid contents ranging between 0.29 and 5.99 RE (rutin equivalents per gram of dried extract). All 13 plant extracts also showed free radical scavenging activity against DPPH· with IC50 ranging between 1.65 and 310.52 μg/ml, while 12 of these extracts exhibited inhibitory activity against NO· radical (IC50 ranging from 19.77 to 157.72 μg/ml). Statistically insignificant positive correlations ( $p>0.5$ ) were found between antibacterial activities of these plants and their antioxidant activities. The different results of this study provide scientific evidence for the use of these antibacterial food plants in the control of different conditions associated with oxidative stress.

Chaya (Jatropha tanjorensis) leafs protect against sodium benzoate mediated renal dysfunction and hepatic damage in rats

Background

Jatropha tanjorensis is a commonly consumed green leafy plant that has found usage in folk medicine. Sodium benzoate (C6H5COONa) is a widely used preservative in food/drink industries with potential cytotoxicity. Protective effect of some leafy plants on xenobiotic-induced toxicity have been established. Hence, this study sought to investigate the protective effect of methanolic leaf extract of Jatropha tanjorensis on sodium benzoate mediated renal and hepatic dysfunction in rats.

Results

Sodium benzoate treatment caused significant (P < 0.05) alteration in kidney (serum urea, uric acid, and creatinine) and liver (aspartate and alanine transaminases, acid and alkaline phosphatases) damage markers, serum albumin, globulin and total protein levels as well as cellular architecture which were significantly reversed in groups treated with the leaf extracts. Phytochemical screening of the leaf extract revealed the presence of terpenoids, saponins, cardiac glycosides, flavonoids and tannins.

Conclusion

Sodium benzoate-induced alterations in the renal and hepatic indices were mitigated following treatment with J. tanjorensis leaf extracts which suggests protective effect of the extract against sodium benzoate intoxication.

Crassocephalum rubens, a leafy vegetable, suppresses oxidative pancreatic and hepatic injury and inhibits key enzymes linked to type 2 diabetes: An ex vivo and in silico study

Crassocephalum rubens falls under the wild edible, under-cultivated traditional leafy vegetables (TLV) in Africa; it is used by locals in managing diabetes mellitus among other diseases. This study investigated the in vitro, ex vivo antioxidant and antidiabetic potentials of different extracts of C. rubens. The ameliorative effects of the extracts on Fe²⁺ -induced oxidative injury was investigated ex vivo together with the effects of the aqueous extract on intestinal glucose absorption and muscle glucose uptake in freshly harvested tissues from normal rats. The aqueous extract was subjected to Liquid Chromatography-Mass Spectrometry (LC-MS) analysis to identify possible bioactive compounds which were then docked with the tested enzymes through in silico modeling. The extracts exhibited antioxidant activity, inhibited α-glucosidase and lipase enzyme activities, intestinal glucose absorption and enhanced muscle glucose uptake compared to controls. Sanguisorbic acid dilactone identified through LC-MS analysis showed a high binding affinity for catalase and lipase enzymes. PRACTICAL APPLICATIONS: The results of this study suggest that the aqueous extract of C. rubens possesses better antioxidant and possible antidiabetic potentials compared to other extracts which could be associated to the synergistic action of its identified bioactive compounds.

Role of reactive oxygen species-total antioxidant capacity status in Telfairia occidentalis leaves-associated spermatoprotective effect: a pointer to fatty acids benefit

Background The present study used reactive oxygen species (ROS)-total antioxidant capacity (TAC) score to understand the role of redox status on the effect of Telfairia occidentalis (TO) on testicular parameters. The fatty acids (FAs) components of methanol extract of TO (METO) and its fractions were also identified with gas chromatography-mass spectrometry. Methods A total of 66 male Wistar rats were randomly divided in a blinded fashion into six oral treatment groups as follows: group I (control, n=6) received 10% ethanol (vehicle for TO administration). Groups II to VI (n=12 rats each) were subdivided into two treatment subgroups (n=6 each) that received 200 mg/kg and 600 mg/kg of METO and its chloroform, petroleum ether, acetone, and ethanol fractions, respectively. All treatments lasted for 30 days. Results The major FAs detected in TO were myristic, palmitic, oleic, linoleic, linolenic, and stearic acids including their esters. Both doses of METO and its fractions increased the semen parameters, TAC and ROS-TAC scores but decreased the ROS when compared with control. Conclusions Using the ROS-TAC score, this study suggests that TO-associated improvement in semen parameters might be partly mediated by a reduction in free radical generation, and that the FAs present in TO might be involved in its spermatoprotective effect.

Betalains in Some Species of the Amaranthaceae Family: A Review

Natural pigments are largely distributed in the plant kingdom. They belong to diverse groups, with distinct biochemical pathways. Betalains with colours that range from yellow to red-violet can de divided into two main subgroups: betaxanthins and betacyanins. These types of pigments are confined into 13 families of the order Caryophyllales and in some genera of higher fungi (Amanita muscaria, Hygrocybe and Hygrophorus). The Amaranthaceae family includes diverse genera in which betalains are present: Alternanthera, Amaranthus, Beta, Chenopodium, Celosia and Gomphrena. The biosynthesis of betalains and their general biological properties were reviwed in the present work. In addition, the types of betalains present in some species of the aforementioned genera, their stability and production, as well as biological attributes, were reviewed.

Evaluation of acute and subacute toxicity of aqueous extract of Crassocephalum rubens leaves in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Crassocephalum rubens is found throughout tropical Africa including the Indian Ocean islands. The leaves are commonly eaten in form of soups and sauces in South-Western Nigeria, also in other humid zones of Africa. Traditionally, it is used as an antidote against any form of poisoning; used to treat stomach and liver complaints; and externally to treat burns, sore eyes, earache, leprosy and breast cancer. In this study, acute and subacute toxicity of aqueous extract of C. rubens leaves was evaluated in rats in order to assess its safety profile.

MATERIALS AND METHODS

In acute toxicity study, rats were given a single oral administration of aqueous extract of C. rubens leaves at graded doses (250-5000mg/kg). The animals were monitored for behavioural changes and possible mortality over a period of 24h and thereafter, for 14 days. In the subacute toxicity study, rats of both sexes were administered C. rubens orally at doses of 250mg/kg, 500mg/kg, 750mg/kg and 1000mg/kg body weight daily, for 28 days. Rats were observed weekly for any changes in general behaviour and body weights. In addition, other relevant parameters were assayed at the end of the main and reversibility study periods.

RESULTS

There was no observed adverse effect; including mortality in the animals. The extract caused no significant difference in the body weights as well as organs weights of treated groups when compared with the control groups. Haematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological assessments were normal in liver and kidney.

CONCLUSIONS

It can therefore be suggested based on the results from this study that aqueous extract of C. rubens leaves, at dosage levels up to 1000mg/kg, is non-toxic and could also offer protection on some body tissues. Aqueous extract of C. rubens could therefore, be considered safe. This study supports the application of Crassocephalum rubens in traditional medicine.

Ultra high performance liquid chromatography-ultraviolet-electrospray ionization-micrOTOF-Q II analysis of flavonoid fractions from Jatropha tanjorensis

Background:

Jatropha tanjorensis (Euphorbiaceae) an exotic traditional plant unique to Thanjavur district of Southern India also commonly called as Catholic vegetable. It has been used traditionally in decoctions for treating various ailments and as a health tonic.

Objective:

The objective of the present work is to study a comprehensive characterization of methanolic extract fractions using ultra high performance liquid chromatography (UHPLC)+-electrospray ionization (ESI)-micrOTOF-Q II and correlate their bioactivities.

Materials and Methods:

Phytoconstituents from J. tanjorensis leaves were extracted with methanol (MeOH) followed by successive chromatography using linear gradient polar solvents system. All fractions obtained were evaluated for their chemical potential using micrOTOF-Q II techniques and identified key molecules were determined for their anticancer and anti-oxidant potential using in vitro methods.

Results:

Successive column chromatography of the MeOH residue yielded six fractions. Compounds such as such as C-glycosylflavones (mono-C-, di-C-), O, C-diglycosylflavones and aglycones were identified for the first time in this plant using UHPLC-ultraviolet-micrOTOF-Q II ESI and a correlation with their anticancer using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay on Ehrlich ascites cells (EAC) and antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl and lipid peroxidation were studied; fraction D extract exhibited the strongest activity against cancer cell.

Conclusions:

LC-mass spectrometry has been successfully applied for a quick separation and identification of the major phytoconstituents. All fractions have shown potent antioxidative activity as compared to standard antioxidant 3,5-di-tert-butyl-4-hydroxytoluene. EAC cell-based cytotoxicity assay also revealed encouraging results. The antioxidant and anticancer activity determined in the present work can be attributed to the presence of flavonoids and flavone glycosides. Present work provides the first scientific report on phytoconstituents of J. tanjorensis and its ethnopharmacological significance.

Modulatory role of kolaviron in phenytoin-induced hepatic and testicular dysfunctions in Wistar rats

Phenytoin, an anticonvulsant agent used for the treatment of epilepsy has been reported to exhibit toxic side effects on the liver and testes. The present study investigated the protective effects of kolaviron (KV, a bioflavonoid from Garcinia kola seeds) against hepatic and testicular damage in rats exposed to phenytoin. The study consisted of four groups of six rats per group. Group I rats received 2 mL/kg of corn alone while group II received 75 mg/kg of phenytoin (PHT) alone. Groups III and IV were co-treated with kolaviron (200 mg/kg KV) and vitamin E (500 mg/kg VTE), respectively, for 14 days. The antioxidant status, hepatic and reproductive functional parameters were subsequently determined. PHT treatment significantly (p < 0.05) increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated lipid peroxidation (LPO) and hydrogen peroxide (H2O2) levels along with significant reduction in the hepatic and testicular levels of glutathione (GSH). Moreover, PHT exposure elicited significant increases in alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels. The significant reduction in seminal epithelium thickness and the diameter of seminiferous tubules was accompanied with marked decrease in sperm motility, sperm count, and viability in PHT-treated rats. However, antioxidant status and the functional indices of liver and testes were restored to near control levels in rats co-treated with KV and VTE. In conclusion, KV and VTE protect the liver and testes against functional impairment due to PHT treatment.

Antimicrobial activity and cytotoxicity of triterpenes isolated from leaves of Maytenus undata (Celastraceae)

Background

Plants of the genus Maytenus belong to the family Celastraceae and are widely used in folk medicine as anti-tumour, anti-asthmatic, analgesic, anti-inflammatory, antimicrobial and anti-ulcer agents, and as a treatment for stomach problems. The aim of this study was to isolate and identify active compounds with antifungal activity from Maytenus undata after a preliminary study highlighted promising activity in crude extracts.

Methods

Sequential extracts of M. undata leaves prepared using hexane, dichloromethane (DCM), acetone and methanol (MeOH) were tested for activity against Cryptococcus neoformans, a fungal organism implicated in opportunistic infections. Bioassay-guided fractionation of the hexane extract using C. neoformans as test organism was carried out to isolate antifungal compounds. The cytotoxicity of compounds isolated in sufficient quantities was evaluated using a tetrazolium-based colorimetric cellular assay (MTT) and a haemagglutination assay (HA).

Results

The hexane extract was most active with an MIC of 20 μg/ml against C. neoformans. The triterpene compounds friedelin (1), epifriedelanol (2), taraxerol (3), 3-oxo-11α-methoxyolean-12-ene-30-oic acid (4), 3-oxo-11α-hydroxyolean-12-ene-30-oic acid (5) and 3,11-dihydroxyolean-12-ene-30-oic acid (6) were isolated. Compound 6 was isolated for the first time from a plant species. The antimicrobial activity of compounds 1, 3, 5 and 6 was determined against a range of bacteria and fungi implicated in opportunistic and nosocomial infections. Compounds 5 and 6 were the most active against all the tested microorganisms with MIC values ranging between 24 and 63 μg/ml, except against Staphylococcus aureus which was relatively resistant. Compounds 1 and 3 had a low toxicity with an LC₅₀ > 200 μg/ml towards Vero cells in the MTT assay. Compounds 5 and 6 were toxic with LC₅₀ values of 6.03±0.02 and 2.98±0.01 μg/ml, respectively. Compounds 1 and 3 similarly were not toxic to the red blood cells (RBCs) but compounds 5 and 6 were toxic, showing HA titer values of 1.33 and 0.67 respectively.

Conclusions

Compounds 5 and 6 were the most active but were also relatively cytotoxic to monkey kidney cells and red blood cells, while the other isolated compounds were less active and less cytotoxic.

A review of the medicinal potentials of plants of the genus Vernonia (Asteraceae)

ETHNOPHARMACOLOGICAL RELEVANCE

The Vernonia genus has about one thousand species and members of the genus are widely used as food and medicine. The aim of this review is to analyze published data on the ethnomedicinal, ethnoveterinary and zoopharmacognostic uses of plants of the Vernonia genus. This will help to identify the state of ethnopharmacological knowledge in regard to this genus and to propose future research priorities.

MATERIALS AND METHODS

The major scientific databases including SciFinder, Sciencedirect, Medline and Google Scholar were queried for information on Vernonia genus using various keyword combinations. The International Plant Name Index was also used to verify the names of species and authors.

RESULTS

A total of 109 Vernonia species were reported in the literature to have medicinal properties. One hundred and five (105) plants were linked to the treatment or management of 44 human diseases or health conditions. Plants of the genus also feature in ethnoveterinary and zoopharmacognostic practices. A total of 12 vernonia species were identified to be used in ethnoveterinary medicine while 2 species are used in self medication practices by chimpanzees and gorillas. In vitro and in vivo research studies reporting the validation of the medicinal properties of some species were also reviewed. One hundred and three bioactive compounds isolated from various Vernonia species were also identified. Vernonia amygdalina was identified as the most frequently used member of the Vernonia genus. The Vernolides, a class of sesquiterpene lactone were identified as the most studied compounds from the genus and show interesting bioactivity in antiplasmodial, antileishmanial, antischistosomial, cytotoxicity, antimicrobial and anti-inflammatory assays.

CONCLUSION

On the basis of results from a combination of in vitro and in vivo efficacy and toxicity studies reported, Vernonia amygdalina holds the most promise for development into a nutraceutical against diabetes and malaria while Vernonia cinerea has potential against cancer and inflammatory conditions. Vernolide A is so far the most promising single agent from a Vernonia species that has potential for development into an anticancer agent. The other Vernonia species and isolated compounds require further studies to ascertain their medicinal potentials.

Hepatic, testicular and spermatozoa antioxidant status in rats chronically treated with Garcinia kolaseed

ETHNOPHARMACOLOGICAL RELEVANCE

Garcinia kola seed is commonly used in African Traditional Medicine as a remedy for liver disorders, hepatitis, bronchitis, throat infections as well as an aphrodisiac and fertility enhancing substance. Owing to the abundance of complex mixture of phenolic compounds in Garcinia kola seed, there is a growing safety concern on its long-term use in folklore medicine. The present study evaluated the hepatic, testicular and spermatozoa antioxidant status in rats chronically treated with Garcinia kolaseed.

MATERIALS AND METHODS

Adult male Wistar rats were randomly assigned to four groups of 10 rats each and were orally administered with Garcinia kola at 0, 250, 500 and 1000mg/kg for 6consecutive weeks. Clinical observations, serum biochemistry, oxidative stress biomarkers, spermatozoa parameters and histopathological examination of the organs were assessed to monitor treatment-related adverse effects inrats.

RESULTS

Long-term treatment of Garcinia kola had no adverse effect on the spermatozoa characteristics but significantly elevated testosterone concentration when compared to the control group. Improvement of antioxidant systems was accompanied by a significant decrease in malondialdehyde level in the liver, testes and spermatozoa of Garcinia kola-treated rats. Histological observation revealed that chronic administration of Garcinia kola had no effect on the liver and testes at all doses when compared with control.

CONCLUSION

Garcinia kola seed boosts the antioxidant status and exhibits no adverse effect on the liver, testes and spermatozoa after a long-term oral exposure inrats.

Antioxidative and chemopreventive properties of Vernonia amygdalina and Garcinia biflavonoid

Recently, considerable attention has been focused on dietary and medicinal phytochemicals that inhibit, reverse or retard diseases caused by oxidative and inflammatory processes. Vernonia amygdalina is a perennial herb belonging to the Asteraceae family. Extracts of the plant have been used in various folk medicines as remedies against helminthic, protozoal and bacterial infections with scientific support for these claims. Phytochemicals such as saponins and alkaloids, terpenes, steroids, coumarins, flavonoids, phenolic acids, lignans, xanthones, anthraquinones, edotides and sesquiterpenes have been extracted and isolated from Vernonia amygdalina. These compounds elicit various biological effects including cancer chemoprevention. Garcinia kola (Guttiferae) seed, known as "bitter kola", plays an important role in African ethnomedicine and traditional hospitality. It is used locally to treat illnesses like colds, bronchitis, bacterial and viral infections and liver diseases. A number of useful phytochemicals have been isolated from the seed and the most prominent of them is the Garcinia bioflavonoids mixture called kolaviron. It has well-defined structure and an array of biological activities including antioxidant, antidiabetic, antigenotoxic and hepatoprotective properties. The chemopreventive properties of Vernonia amygdalina and Garcinia biflavonoids have been attributed to their abilities to scavenge free radicals, induce detoxification, inhibit stress response proteins and interfere with DNA binding activities of some transcription factors.

Ethnopharmacological survey among migrants living in the Southeast Atlantic Forest of Diadema, São Paulo, Brazil

BACKGROUND

Understanding how people of diverse cultural backgrounds have traditionally used plants and animals as medicinal substances during displacements is one of the most important objectives of ethnopharmacological studies. An ethnopharmacological survey conducted among migrants living in the Southeast Atlantic Forest remnants (Diadema, São Paulo, Brazil) is presented herein.

METHODS

Ethnographical methods were used to select and interview the migrants, and botanical and zoological techniques were employed to collect the indicated resources.

RESULTS

We interviewed five migrants who described knowledge on 12 animals and 85 plants. Only 78 plants were present in Diadema, they belong to 37 taxonomic families; 68 were used exclusively for medicinal purposes, whereas 10 were reported to be toxic and/or presented some restriction of use. These taxa were grouped into 12 therapeutic categories (e.g., gastrointestinal disturbances, inflammatory processes or respiratory problems) based on the 41 individual complaints cited by the migrants. While the twelve animal species were used by the migrants to treat nine complaints; these were divided into six categories, the largest of which related to respiratory problems. None of the animal species and only 57 of the 78 plant species analysed in the present study were previously reported in the pharmacological literature; the popular knowledge concurred with academic findings for 30 of the plants. The seven plants [Impatiens hawkeri W. Bull., Artemisia canphorata Vill., Equisetum arvensis L., Senna pendula (Humb. & Bonpl. ex Willd.) H.S. Irwin & Barneby, Zea mays L., Fevillea passiflora Vell. and Croton fuscescens Spreng)] and the two animals (Atta sexdens and Periplaneta americana) that showed maintenance of use among migrants during their displacement in Brazilian territory, have not been studied by pharmacologists yet.

CONCLUSIONS

Thus, they should be highlighted and focused in further pharmacology and phytochemical studies, since the persistence of their uses can be indicative of bioactive potentials.

Traditional antimalarial phytotherapy remedies used by the South Coast community, Kenya

AIM OF THE STUDY

This study was conducted to document herbal medicines used in the treatment of malaria as well as the existing knowledge, attitudes and practices related to malaria recognition, control and treatment in South Coast, Kenya.

METHODS

Data was collected using semistructured questionnaires and interviews. A focused group discussion held with the community members, one in each of the study villages supplemented the interview and questionnaire survey.

RESULTS

The respondents were found to have a good understanding of malaria and could distinguish it from other fever types. They were also aware that malaria was spread by mosquitoes. Malaria prevalence was high, and affected individuals an average of four times a year. Community members avoided mosquito bites by using mosquito nets, clearing bushes around their homesteads and burning plant parts to generate smoke. They prevented and treated malaria by taking decoctions or concoctions of traditional herbal remedies. Forty plant species in thirty-five genera distributed in twenty-four families were used as antimalarials in the study area. Five plant species, namely; Heeria insignis Del. (Anacardiaceae), Rottboelia exaltata L.F (Gramineae), Pentanisia ouranogyne S. Moore (Rubiaceae), Agathisanthenum globosum (A. Rich) Hiern (Rubiaceae), and Grewia trichocarpa Hochst ex A. Rich (Tiliaceae) are documented for the first time in South Coast, Kenya, for the treatment of malaria.

CONCLUSIONS

The plants documented in the current study are a potential source for new bioactive compounds of therapeutic value in malaria treatment. The results provide data for further pharmacological and toxicological studies and development of commercial antimalarial phytotherapy products.

Evaluation of selected South African plant species for antioxidant, antiplatelet, and cytotoxic activity

The antioxidant, antiplatelet, and cytoxoxic effects of seven South African plant extracts, namely, Combretum vendae A.E. van Wyk (Combretaceae), Commiphora harveyi (Engl.) Engl. (Burseraceae), Khaya anthotheca (Welm.) C.DC (Meliaceae), Kirkia wilmsii Engl. (Kirkiaceae), Loxostylis alata A. Spreng. ex Rchb. (Anacardiaceae), Ochna natalitia (Meisn.) Walp. (Ochnaceae), and Protorhus longifolia (Bernh. Ex C. Krauss) Engl. (Anacardiaceae), were evaluated using established in vitro assays. All the extracts showed comparably low toxicity except for the extract of C. harveyi that showed high hemagluttination assay titer value, which indicates toxicity. The extracts of P. longifolia, K. wilmsii, O. natalitia, L. alata, C. harveyi, and C. vendae exhibited antioxidant properties in the qualitative assay using DPPH. In the quantification of antioxidation using ABTS, only the extracts of P. longifolia, L. alata, and C. vendae showed antioxidant activity with respective TEAC values of 1.39, 1.94, and 2.08. Similarly, in the quantitative DPPH assay, L. alata (EC50, 3.58+/-0.23 microg/mL) and K. wilmsii (EC50, 3.57+/-0.41 microg/mL) did not differ significantly (p<or=0.05) from the control. K. anthotheca showed a higher EC50 (176.40+/-26.56 microg/mL) value, and differed significantly (p<or=0.05) from all the other extracts and control. In addition, the extracts of C. vendae and C. harveyi showed significant (p<or=0.05) antiplatelet activity and did not differ from the control (aspirin) with EC50 of 0.06+/-0.01 microg/mL and 0.19+/-0.00 microg/mL, respectively. Lower EC50 values in the antioxidant and antiplatelet studies are indicative of superior activity of the plant extract against oxidation and platelet aggregation.

Antimalarial herbal remedies of Msambweni, Kenya

Malaria is a serious cause of mortality globally. The disease is of regional concern in Africa and of national interest in Kenya due to its high morbidity and mortality as a result of development of resistant strains of Plasmodium falciparum to many existing drugs such as chloroquine. Alternative medicine using herbal remedies are commonly used to treat malaria in Kenya. However, plants used in some rural areas in Kenya are not documented. Many antimalarial drugs have been derived from plants. This study was conducted to document medicinal plants that are traditionally used by the Msambweni community of Kenyan South Coast to treat malaria, where the disease is endemic. Herbalists were interviewed by administration of semistructured questionnaires in order to obtain information on medicinal plants traditionally used for the treatment of malaria. Focused group discussions held with the herbalists supplemented the interview and questionnaire survey. Twenty-seven species of plants in 24 genera distributed in 20 families were reported to be used in this region for the treatment of malaria. Labiatae, Rutaceae and Liliaceae families had each eleven percent of the plant species reported and represented the species that are most commonly used. Thirteen plant species, namely; Aloe deserti Berger (Liliaceae), Launea cornuta (Oliv and Hiern) C. Jeffrey (Compositae), Ocimum bacilicum L. (Labiatae), Teclea simplicifolia (Eng) Verdoon (Rutaceae), Gerranthus lobatus (Cogn.) Jeffrey (Cucurbitaceae), Grewia hexaminta Burret. (Tiliaceae), Canthium glaucum Hiern. (Rubiaceae), Amaranthus hybridus L. (Amaranthaceae), Combretum padoides Engl and Diels. (Combretaceae), Senecio syringitolius O. Hoffman. (Compositae), Ocimum suave Willd (Labiatae), Aloe macrosiphon Bak. (Liliaceae) and Laudolphia buchananii (Hall.f) Stapf. (Apocynaceae) are documented from this region for the first time for the treatment of malaria. These results become a basis for selection of plants for further pharmacological, toxicological and phytochemical studies in developing new plant based antimalarial drugs.

The analgesic and antiplasmodial activities and toxicology of Vernonia amygdalina

Vernonia amygdalina possesses several bioactive compounds and is used in traditional medicines of southwestern Uganda, along with other regions. Its analgesic potential has not been investigated thus far. The present study examines the antinociceptive potential of the aqueous leaf extract (50-200 mg/kg) using three models of nociception (acetic acid-induced writhing, formalin test, and tail-flick test), antiplasmodial activity, and toxicology of the extract. The results show the extract significantly inhibits acetic acid-induced writhing and the formalin test in mice but did not give a potent effect in the tail-flick test, suggesting that the extract may have peripheral and central analgesic properties. The extract also exhibited significant antiplasmodial activity in mice against Plasmodium berghei with 73% inhibition in the group that received a dose of 200 mg/kg i.p. daily for 4 days. Toxicology results show no clinical signs of toxicity or adverse toxicological effects in the treated groups, except for a significant decrease in red blood cell count and a dose-dependent increase in serum bilirubin. These changes were within control values based on historical reference ranges at doses of 500-2,000 mg/kg/day for 14 consecutive days as compared to the control. This study supports the traditional use of V. amygdalina as an alternative therapy for malaria and the symptomatic relief of pain usually associated with malaria.

Clinical effects of Garcinia kola in knee osteoarthritis

Objectives

Over the past years, there has been a growing number of knee osteoarthritis (KOA) patients who are not willing to comply with long-term non-steroidal anti-inflammatory drugs (NSAID) treatment and wish to use herbal anti- rheumatic medicine. This study assessed the clinical effects of Garcinia kola (GK) in KOA patients.

Patients and methods

Prospective randomized, placebo controlled, double blind, clinical trial approved by the institutional medical ethics review board and written informed consent obtained from each patient. All KOA patients presenting at the Obafemi Awolowo University Teaching Hospital complex were recruited into the study. The patients were grouped into four (A = Placebo, B = Naproxen, C = Garcinia kola, D = Celebrex). The drugs and placebo were given twice a day per oral route. Each dose consisted of 200 mg of G. kola, Naproxen (500 mg), Celebrex (200 mg) and Ascorbic acid (100 mg). The primary outcome measure over six weeks study period was the change in mean WOMAC pain visual analogue scales (VAS). Secondary outcome measures included the mean change in joint stiffness and physical function (mobility/walking).

Results

143 patients were recruited, 84 (58.7%, males – 24, females – 60) satisfied the selection criteria and completed the study. The effect of knee osteoarthritis bilateralism among the subjects was not significant on their outcome (p > 0.05). The change in the mean WOMAC pain VAS after six weeks of G. kola was significantly reduced compared to the placebo (p < 0.001). Multiple comparisons of the mean VAS pain change of G. kola group was not lowered significantly against the naproxen and celebrex groups (p > 0.05). The onset of G. kola symptomatic pain relief was faster than the placebo (p < 0.001). However, it was slower than the active comparators (p > 0.05). The duration of therapeutic effect of Garcinia kola was longer than the placebo (p > 0.001). G. kola period of effect was less than naproxen and celebrex (p < 0.001). G. kola subjects had improved mean change mobility/walking after six weeks better than the control group(p < 0.001). The mean change in mobility of the G. kola group when compared to the active comparators was not significantly better (p < 0.05). The mean change of knee joint stiffness (p < 0.001) and the change of mean WOMAC score (p < 0.001) were improved on Garcinia kola as compared to the placebo. The mid term outcome of eleven Garcinia kola subjects after cessation of use had a mean pain relief period of 17.27 +/- 5.15 days (range: 9–26 days). There was no significant cardiovascular, renal or drug induced adverse reaction to Garcinia kola.

Conclusion

Garcinia kola appeared to have clinically significant analgesic/anti-inflammatory effects in knee osteoarthritis patients. Garcinia kola is a potential osteoarthritis disease activity modifier with good mid term outcome. Further studies are required for standardization of dosages and to determine long-term effects.

A new 14,15-dinor-labdane Glucoside from Crassocephalum Mannii

A new 14,15-dinor-labdane glucoside, named crassoside A (1), was isolated from the aerial parts of Crassocephalum mannii. The structure of 1 was elucidated on the basis of spectroscopic analysis (1H NMR, 13C NMR, HMQC, HMBC and NOEs). Compound 1 demonstrated a low inhibitory effect against COX-1, but was inactive against COX-2.

Cyclooxygenase (COX)-1 and -2 inhibitory labdane diterpenes from Crassocephalum mannii

Two new labdane diterpenes, 8alpha,19-dihydroxylabd-13 E-en-15-oic acid (1) and 13,14,15,16-tetranorlabdane-8alpha,12,14-triol (2), as well as an acetylated derivative, 8alpha-O-beta-D-glucopyranosyllabd-13 E-ene-15,19-diol-8alpha-2',3',4',6'-hexaacetate (3a), were isolated from the aerial parts of Crassocephalum mannii. The structures of 1, 2, and 3a were elucidated by spectroscopic data analysis. Selective inhibitory activity for 1 and 2 and their acetate derivatives, 1a and 2a, against cyclooxygenases (COX-1 and COX-2) was detected.