Omonike O. Ogbole

Antimalarial Ethnobotany: In Vitro. Antiplasmodial Activity of Seven Plants Identified in the Nigerian Middle Belt

Abstract Seven methanol extracts of seven plants from seven plant families were screened for antimalarial properties. The plants were identified and selected from Gboko and Kastina-Ala local government areas in the Tivland ethnobotany in the Middle Belt Zone of Nigeria. Methanol plant extracts were evaluated for in vitro. antimalarial properties using the lactate dehydrogenase technique, with a multiresistant strain of Plasmodium falciparum. K1. Quantification of activity was by estimation of the concentration of extracts that inhibited 50% growth of parasite (IC50) in µg/ml. Of the seven plants screened, Erythrina senegalensis. DC (Leguminosae), Pericopsis elata. Harms (Papilionaceae), and Bridelia micrantha. Benth (Fabaceae) had IC50 values of 99.7, 124.8, and 158.7 µg/ml, respectively. Nauclea latifolia. SM (Rubiaceae) extract exhibited the least activity in the assay with an IC50 value of 478.9 µg/ml.

Cajachalcone: An Antimalarial Compound from Cajanus cajan Leaf Extract.

Cajanus cajan L, a member of the family Fabaceae, was identified from the Nigerian antimalarial ethnobotany as possessing antimalarial properties. The bioassay-guided fractionation of the crude methanol extract of C. cajan leaves was done in vitro using the multiresistant strain of Plasmodium falciparum (K1) in the parasite lactate dehydrogenase assay. Isolation of compound was achieved by a combination of chromatographic techniques, while the structure of the compound was elucidated by spectroscopy. This led to the identification of a cajachalcone, 2′,6′-dihydroxy-4-methoxy chalcone, as the biologically active constituent from the ethyl acetate fraction. Cajachalcone had an IC50 value of 2.0 μg/mL (7.4 μM) and could be a lead for anti-malarial drug discovery.

Phytochemicals from Kigelia pinnata Leaves Show Antioxidant and Anticancer Potential on Human Cancer Cell Line

Studies suggest that the traditional applications of Kigelia pinnata leaves have beneficial effects against oxidative stress-mediated diseases and cancers. The pulverized dried leaves of K. pinnata were extracted with hexane, ethyl acetate, and methanol sequentially, and the crude extracts were fractionated by silica gel column chromatography with solvent gradient of increasing polarity. 3-hydro-4,8-phytene, trans-phytol, (9Z,12Z)-methyl octadeca-9,12-dienoate, and two oil fractions were obtained. The chemical compositions of chromatographic fractions were determined using gas chromatography-mass spectroscopy. The structure elucidations of the isolated compounds were based on FTIR, MS, and NMR spectral data analyses. These along with the crude extracts were examined for their antioxidant activities using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) assays. Total phenolic contents were also determined. The crude extracts and purified compounds were evaluated on the rhabdomyosarcoma human cancer cell for their cytotoxicity using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assays. The methanol extract was richer in phenolics and was most potent as antioxidant and cytotoxic agent among all the substances tested. Among the fractions and pure compounds, the two oil fractions showed more cytotoxicity potency, with IC50s of 143.4±0.5 and 147.9±1.3 ng/mL, which is more significant than the reference standard, cyclophosphamide (165.6±1.0 ng/mL). 3-hydro-4,8-phytene showed lower antioxidant and cytotoxicity potential (IC50=1818±5.2 μg/mL and 171.7±0.8 ng/mL, respectively). Trans-phytol did not show a high cytotoxic power (IC50=769.8±4.3 ng/mL). The comparatively high cytotoxicity index of (9Z, 12Z)-methyl octadeca-9,12-dienoate (IC50=153.3±0.1 ng/mL) indicated that it may be one of the principal cytotoxic agent in the ethyl acetate extract. These results suggest that the leaves of K. pinnata possess tumor cytotoxic potential and could be part of a drug combination for future cancer chemotherapy.

Traditional anti-fever phytotherapies in Sagamu and Remo North Districts in Ogun State, Nigeria.

An ethnobotanical survey was conducted to identify the medicinal plants in Sagamu Local Government Area (LGA), and Remo North LGA of Ogun State, Nigeria, implicated in the treatment of various types of fever. The survey tools consisted of a semi-structured questionnaire and oral interviews. Seventy respondents mostly ages 31 to 50 covered in this survey were drawn from among the villagers, herbalists, herb sellers, traditional medical practitioners, students, community leaders, and elders who are mostly educated. Four types of fever including malaria, yellow fever, typhoid, and cold were identified with malaria and yellow fever being very common. The majority of the respondents were quite knowledgeable in the etiology, symptoms, and seasonality of all fevers except cold. Survey results document 116 anti-fever herbal recipes being administered as oral decoction or infusion for both curative and preventive purposes. Treatment is usually devoid of known side effects. Cymbopogon citratus, Citrus aurantifolia, Enantia chlorantha, Carica papaya, Morinda lucida, and Lawsonia inermis were frequently included in anti-fever herbal recipes.

Energy Dispersive - XRF Metal Analysis and Cancer Cell Line Cytotoxicity of Kigelia pinnata Root

Human exposure to heavy metals is attributed to consumption of herbs grown in polluted environment. The objective of this study was to assess the health risks associated with metals toxicity in Kigelia pinnata root and also evaluate the cytotoxic potential of the root on rhabdomyosarcoma, RD cancer cell line. Energy dispersive X-Ray Fluorescence, ED-XRF was employed for the assessment of the total metal profile of the root while the hexane, ethylacetate and methanol extracts of the root obtained through exhaustive sequential extraction were evaluated on the RD cancer cell line for its cytotoxicity index using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, MTT cell viability assay. All the extracts showed high cytotoxicity. However, ethylacetate extract (IC50, 142.2 ± 1.1 ng/mL) showed the highest activity compared to the reference drug, cyclophosphomide (IC50, 165.6 ± 1.0 ng/mL). Heavy metal concentrations in the root of plant grown in the forest did not exceed the permissible limits set by the EU regulatory body. The health risk index of the root of plant is considered relatively safe for therapeutic purposes. With regards to metal toxicity, the study indicated that there is a relative absence of health risks associated with the ingestion of Kigelia pinnta root extracts while administering for treatment of cancer related diseases in traditional medicine. The root extracts could serve as a basis for development of disease-oriented drugs or nutraceuticals. There is however a need for caution since iron concentration is high.

Acridone alkaloids from the stem bark of Citrus aurantium display selective cytotoxicity against breast, liver, lung and prostate human carcinoma cells

ETHNOPHARMACOLOGICAL RELEVANCE Citrus aurantium L. (Rutaceae) is used, either singly or as a part of a polyherbal preparation, in Nigerian traditional medicine for the management of cancer and inflammatory diseases. Currently, there is a dearth of knowledge demonstrating its anticancer potential. AIM OF THE STUDY This study was carried out to determine the in vitro cytotoxicity of the crude extract of the stem bark of C. aurantium, identify and isolate the bioactive constituents and to establish the cytotoxicity of such constituents. MATERIALS AND METHODS The powdered bark of C. aurantium was extracted by MeOH at room temperature (25-34 °C) and the crude extract was partitioned successively, with n-hexane, dichloromethane and methanol. Amongst the fractions, the DCM fraction was the most active and compounds were isolated from this fraction using a combination of chromatographic techniques. The structures of the isolated compounds were elucidated by spectroscopic means (MS, 1D and 2D NMR). The cytotoxicity of the extract, and the isolated compounds were evaluated by the MTT assay against four human cancer cell lines: A549 (lung), HepG2 (liver), MCF7 (breast) and PC3 (prostate). The selectivity of the isolated compounds was assessed using the normal human prostate epithelium cells (PNT2). RESULTS AND DISCUSSION Of the three plant fractions, the DCM fraction showed significant cytotoxicity, with its highest activity against A549 cells (IC50 = 3.88 µg/mL) and the least activity on HepG2 cells (IC50 = 5.73 µg/mL). Six acridone alkaloids, citrusinine-I (1), citracridone-I (2), 5-hydroxynoracronycine (3), natsucitrine-I (4), glycofolinine (5) and citracridone-III (6), were isolated from the DCM fraction of C. aurantium. The isolated compounds demonstrated potent to moderate cytotoxicity (IC50 = 12.65-50.74 µM) against the cancer cells under investigation. It is noteworthy that the compounds exerted cytotoxicity at least four times more selective towards the carcinoma cells than the PNT2 cells. CONCLUSION The results obtained from this study have provided some evidence for the ethnomedicinal use of C. aurantium against cancer and the acridone alkaloids present in its stem bark, have appeared to be responsible for the anticancer effects.

Antioxidant, Brine Shrimp Lethality, and Antiproliferative Properties of Gel and Leaf Extracts of Aloe schweinfurthii and Aloe vera

ABSTRACT Leaf and gel extracts of Aloe schweinfurthii and A. vera were subjected to in vitro antioxidant assay using 2,2-diphennyl-1-picryl hydrazyl (DPPH), brine shrimp lethality bioassay, and cytotoxicity using the MTT assay with two human cancer cell lines: Rd and Hep-2c. Extracts of A. schweinfurthii gel had IC50 values of 44.59; A. vera gel, 41.48, and A. vera leaf, 38.84 µg.mL–1, had similar DPPH radical-scavenging properties and were more active than A. schweinfurthii leaf. Ascorbic acid had an IC50 of 9.26 ± 0.14 µg.mL–1. Aloe vera leaf (LC50 = 325 ± 5.38 µg.mL–1) was more active than the other three extracts in the BSL assay. The gel extracts of A. schweinfurthii (CC50 = 4.06 µg.mL–1on Rd and 9.00 µg.mL–1 on Hep-2c) and A. vera (CC50 = 4.31 µg.mL–1 on Rd, 9.06 µg.mL–1 on Hep-2c) elicited similar and more potent cytotoxicity comparable to cyclophosphamide, with CC50 = 2.2 µg.mL–1 on Rd and 2.66 µg.mL–1 on Hep-2c. Leaf extracts were less active than gel extracts. This study showed that A. schweinfurthii gel, A. vera gel and leaf had weak DPPH activity which were similar. Aloe vera and A. schweinfurthii did not elicit potent cytotoxicity in BSL assay. The gels from both Aloe species displayed antipoliferative activity on Rd and Hep-2c, two human cell cancer lines.

Alpha-amylase Inhibition and Brine Shrimp Lethality Activities of Nine Medicinal Plant Extracts from South-West Nigerian Ethnomedicine

ABSTRACT Acanthospermum hispidum, Alchornea laxiflora, Calyptrochilum christyanum, Heliotropicum indicum, Holarrhena floribunda, Ipomoea asarifolia, Nauclea diderrichii, Piper guineense, and Tetracera scandens were extracted into methanol and screened for the availability of alpha-amylase inhibitors. Plant extracts’ toxicity was determined by brine shrimp lethality assay (BSLA). The most active plant, Nauclea diderichii, was fractionated into four solvent systems (n-hexane fractions, ethyl acetate, dichloromethane, and n-butanol) and tested. All the extracts showed varying degrees of alpha-amylase inhibitory activity. N. diderrichii with IC50 = 248.30 ± 0.27 µg.mL–1 had the highest inhibitory activity, while its butanol fraction with IC50 = 137.8 µg.mL–1 had activity comparable to the standard α-amylase inhibitor acarbose (IC50 = 177.50 ± 0.42 µg.mL–1). LC50 values for BSLA ranged from 11.35 to 1,127.50 µg.mL–1, with T. scandens being the most toxic with 11.35 µg.mL–1 and N. diderrichii the least toxic with 1,127.50 µg.mL–1.

Resveratrol derivatives from Commiphora africana (A. Rich.) Endl. display cytotoxicity and selectivity against several human cancer cell lines

Commiphora africana (A. Rich.) Endl. (Burseraceae) is a medicinal plant widely used in Nigerian ethnomedicine. The in vitro cytotoxicity of the stem bark extract of C. africana and isolated cytotoxic compounds was investigated. Three resveratrol derivatives: (E)‐resveratrol 3‐O‐rutinoside (1), 5‐methoxy‐(E)‐resveratrol 3‐O‐rutinoside (2), and pinostilbene (3), together with 3‐hydroxy‐5‐methoxybenzoic acid (4) were isolated from the methanol fraction of C. africana. Their structures were determined by extensive analysis of their HREIMS and NMR spectra. The cytotoxicity of the isolated compounds against four human carcinoma cells was determined using the MTT assay. Compound 1 displayed the highest antiproliferative effect on the cell lines, with IC50 values of 16.80, 21.74, 17.89, and 17.44 μM, against MCF7, A549, PC3, and HepG2 human cancer cell lines, respectively. In addition, compounds 1–3 showed low toxicity against normal human prostate cell line, with selectivity indices greater than five across the carcinoma cells, indicating that the compounds possess potential in the development of low‐toxicity chemotherapeutic agents. These results support the traditional use of this plant in the treatment of cancer.

Antiviral potentials of Lactobacillus plantarum, Lactobacillus amylovorus, and Enterococcus hirae against selected Enterovirus

Enteroviruses have been associated with a host of clinical presentations including acute flaccid paralysis (AFP). The site of primary replication for most enteroviruses is the gastrointestinal tract (GIT) and lactic acid bacteria (LAB) may confer protection in the GIT against them. This study therefore investigates the antiviral potential of some selected lactic acid bacteria against enterovirus isolates recovered from AFP cases. The antiviral activities of Lactobacillus plantarum, Lactobacillus amylovorus, and Enterococcus hirae in broth culture, their cell-free supernatant (CFS), and bacterial cell pellets were assayed against Echovirus 7 (E7), E13, and E19 in a pre- and post-treatment approach using cytopathic effect (CPE) and cell viability (MTT) assay. The tested Lactobacillus plantarum, Lactobacillus amylovorus, and Enterococcus hirae strains have good antiviral properties against E7 and E19 but not against E13. Lactobacillus amylovorus AA099 shows the highest activity against E19. The pre-treatment approach displays better antiviral activities compared to post-treatment approach. The LAB in broth suspension have better antiviral activities than their corresponding CFS and bacterial pellet. Lactic acid bacteria used in this study have the potential as antiviral agents.