Sub-Acute toxicological evaluation of the aqueous stem bark extract of Brachystegia eurycoma (harms

Brachystegia eurycoma is a mainstay in the treatment of malaria, diabetes, hypertension, microbial infections and inflammatory conditions in folkloric medicine in Eastern Nigeria. Thus, the present study investigated the in vivo sub-acute toxicity of its aqueous stem bark extract. Toxicological evaluation was done using organ weight index, haematological, biochemical and histopathological parameters, following daily oral administration of 100, 400 and 800 mg/kg of the extract to albino Wistar rats for 14 days. The extract at all doses caused no significant changes in the organ weight index of selected organs except for 100 mg/kg which caused a significant (p < 0.05) increase in the weight of lungs compared to control. There was significant elevation of white blood cells and lymphocytes observed at all doses of extract tested. However, B. eurycoma caused mild periportal infiltrates of chronic inflammatory cells and Kupffer cell activation in the liver, lymphoid  aggregate activation in the lungs as well as activation of lymphoid follicle and sinus histiocyte in the spleen, thus indicating activation of the immune system. Overall, the results suggest that aqueous extract of B. eurycoma stem bark is not toxic in rats, although it has a tendency to activate the immune system.Keywords: B. eurycoma, immunity, spleen, toxicity

Anticancer and antioxidant studies of the methanol extract and fractions of Conyza sumatrensis (retz.) E. H. Walker (asteraceae

The in vitro antiproliferative and antioxidant studies of the leaf extract and fractions of Conyza sumatrensis was investigated by applying the Sulforhodamine-B and 2, 2-diphenyl-1-picrylhydrazyl assays (DPPH-RSA) respectively. While the antiproliferative activity was carried out at 1-250 and 1-100 μg/ mL for the extract and fractions against breast (MCF-7) and lung (NCI-H460) cancer cell lines, the antioxidant study was conducted using DPPH at 31.25 -500 μg/ mL with the total phenolic and flavonoid contents calculated as well with reference to quercetin and gallic acid respectively. The extract and fractions were observed to elicit cytotoxic and growth inhibitory effects against breast (MCF-7) and lung cancer cell lines (NCI-H460) respectively. At 250 μg/mL, the extract of C. sumatrensis gave cytotoxicity of –1.76 ± 0.20 % against MCF-7 cell lines and inhibited growth of NCI-H460 at +94.40 ± 1.0 % respectively. While the chloroform fraction at 100 μg/mL gave -5.38 ± 0.33 % and 91 ± 1.61 % against MCF-7 and NCI-H460 cell lines, the aqueous fraction was observed to be inactive. For the DPPH-RSA activity, the chloroform fraction demonstrated an IC50 value of 125.5 μg/ mL compare to quercetin at 62.5 μg/ mL. The bioactivities were more pronounced in the chloroform fraction. This work has shown that C.  sumatrensis has antiproliferative and antioxidant activities which could be tied to the secondary metabolites present in the plant

Chemical composition and anticancer effects of Zingiber officinale volatile oil

Zingiber officinale rhizome is used in ethnomedicine in treating tumor-related ailments. This study was undertaken to evaluate the cytotoxic effects of this plant. The oil was extracted using a Clavenger apparatus by hydro-distillation method. Preliminary screening was carried out with brine shrimp cytotoxicity test at 10-1000 µg/mL. The volatile oil was further tested on breast cancer (AU 565) and cervical cancer (HeLa) at 50 µg /mL using MTT assay and later subjected to GCMS analysis. LC50 of 157.75 µg/mL was obtained in the brine shrimp mortality assay. Z. officinale oil showed high anticancer activities with 50 and 43 % inhibitions against HeLa and AU 565 cells respectively. GCMS analysis revealed the major constituents of Z. officinale oil as a-citral (11.68 %) and a-citral (10.18 %). These results suggest the medicinal potency of this plant oil

Chemical composition and anticancer effects of Hyptis Suaveolens L. Poit (lamiaceae) volatile oil

The leaf of Hyptis suaveolens have found application in ethnomedicine in the treatment of various ailments including those that are related to tumor and cancer. This study was therefore undertaken to evaluate the cytotoxic effects of its volatile oil. Volatile oil distilled from freshly collected leaves using a Clavenger-type apparatus was screened using tadpoles of Raniceps ranninus (10-40 µg/mL) and brine shrimp of Artemia salina (10-1000 µg/mL) with bench-top assay procedures for cytotoxicity while growth inhibitory activity was assessed using radicles of Sorghum bicolor seeds (1-30 mg/mL). The essential oils were further tested on breast cancer (AU 565) and cervical cancer (HeLa) at 50 µg /mL using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay and afterwards subjected to Gas Chromatography Mass Spectrometric (GCMS) analysis for its constituents. An LC50 of 188.67 and 8 µg/mL were obtained in the brine shrimp mortality and tadpole lethality assays respectively. The oil showed inhibitions of 86.74 and 21.8 % against AU 565 and HeLa cells respectively. GCMS analysis revealed the major constituents as sabinene (10.64 %) and (-)-4-terpineol (7.27 %). These results support its use in treating tumor-related ailments and should be considered for further studies

Isolation of the antidiarrhoeal tiliroside and its derivative from Waltheria indica leaf extract

The antidiarrhoeal effect of Waltheria indica methanol extract and fractions have been reported earlier but, the present work examined the intestinal relaxant effects of two flavonoid-phenyl propanoids isolated from the methanol extract. The active aqueous fraction was subjected to vacuum liquid chromatography using dichloromethane with increasing concentration of ethyl acetate, and that of methanol and water successively. The ten (10) fractions obtained were combined to give seven (7). The fraction 2 (C, D) was subjected to preparative thin layer chromatography on silica gel GF254 (10-40μm) using CHCl3-CH3OH (8:2) to obtain compound coded F2. Fraction 4 (F) was subjected to column chromatography using silica gel (60-120μm mesh) and eluted with  dichloromethane with increasing concentrations of methanol. Fractions 9-28 were combined and subjected to column  chromatography using chloroform with increasing concentration of methanol. The fractions 1-16 of these were purified on Sephadex LH-20 to obtain compound BAA. The identities of the two compounds were established using spectroscopic methods. The  antidiarrheal effect of compound F2 was evaluated on mice using charcoal transit (100,200, 400mg/kg), castor oil (40, 60 mg/kg)  while the two compounds were examined for their inhibitory effects on Ach-induced ileum contraction. The effects of the  compounds were compared with loperamide (3mg/kg) and atropine (80μg). Compounds F2 and BAA were identified as tiliroside and 3’’’, 5’’’-dimethoxy tiliroside respectively. Tiliroside inhibited the charcoal transition in the animals in a dose dependent pattern with 400mg/ mL eliciting 63.41% inhibition compared to 59.23% produced by loperamide. The compound also elicited significantly (P<0.05) prolonged onset of stooling and reduced the number and weight of stools produced lower than the control. The two  compounds drastically inhibited the Ach-induced contractions of the ileum. The compound, tiliroside at 10mg, completely abolished  the contraction by Ach unlike 3’’’, 5’’’-dimethoxy tiliroside which reduced the contraction to 1.92% at 20mg. The identified compounds seem to be responsible for the ethnomedicinal use of the plant in treating diarrhea

Evaluation of the antidepressant activity of methanol extract and fractions of Parquetina nigrescens (Asclepidiaceae) leaves in mice

Parquetina nigrescens is used in ethnomedicine for the management of pain, diabetes, wounds and central nervous system disorders. This study investigated the toxicity profile and antidepressant effects of methanol extract and fractions of leaves of P. nigrescens in murine models of depression. Phytochemical screening was conducted and the mean lethal dose was estimated. Antidepressant activity of the methanol extract, aqueous and chloroform fractions was evaluated using the forced swim and tail suspension tests at doses of 50, 100 and 200 mg/kg with imipramine (15 mg/kg) as the standard drug. Changes in body weights and organ weight ratio were also evaluated following treatment with P. nigrescens for 2 weeks. The mean lethal dose was estimated to be greater than 5 g/kg. Lower doses (50 and 100 mg/kg) of P. nigrescens significantly (p<0.05) reduced periods of immobility in both the forced swim and tail suspension tests. The aqueous fraction was more potent at ameliorating depression; no changes in body weights and organ weight ratios were recorded. The results obtained suggest that the leaf of P. nigrescens possesses antidepressant property which may account for its use in ethnomedicine.Keywords:  Parquentina nigrescens, antidepressant, forced swim test, methanol extract, phytochemical test

Preliminary in vitro screening of some spices and medicinal plants from Edo and Rivers States, Nigeria for reducing enteric methane production in ruminants

Methane gas produced by ruminants during feed fermentation contributed to global warming as well as poor efficiency of food utilization.  Mitigating ruminal methane production through anti-microbial feed additive has serious health implications. A preliminary study of the potential of medicinal plants and spices from Edo and Rivers State, as possible replacement to antibiotic feed additives was carried out. Medicinal plants and  spices were purposefully sampled, dried at 40oC, milled and 10 mg was added with 190 mg of substrate in a preweighed nylon incubation bags. Bags and their contents were incubated using 30 mL of buffered rumen liquor in 100 mL syringes following the standard procedure of in vitro fermentation. Variables monitored were 24h total gas volume, short chain fatty acids (SCFA), methane (CH ) gas, dry matter degradability (DMD) as well as some chemical, cell wall and 4 anti-nutritive components. Results revealed that adding the medicinal plants and spices as feed additives did not depress gas production in most cases (19.5 – 29.50 mL, 17.75 – 30.00 mL and 12.00 – 29.00 mL for Edo medicinal plants, Edo spices and Rivers  medicinal plants respectively) and also did not depress DMD (> 50%). Azadirachta indica stem reduced CH4 production mostly by 53.56% while Dennttia tripetala did by 47.69% among the Edo medicinal plants and spices, respectively. In Rivers State, Amaranthus spinosus gave the highest value of 60.33% CH reduction. In the same bracket of similar and good CH4 reduction potentials were Alstonia boonei leaves (49.06%),  Newbouldia laevis root (41.50%), Euphorbia heterophyla (37.97%), Allium crispum (47.31%), Allium cepa (46.80%), Aframomum mueguata (46.54%), Capsicum annum (47.32%), Ageratum conyzoides (56.52%), Lagenaria breviflora (48.03%) and Centrosema molle (45.08%). All the medicinal plant and spices with potential for CH4 reduction had corresponding high SCFA 4 values (0.46 – 0.65 Mmol) with tannin (%) and saponin (%) contents of  0.011 – 17.50 and 0.01 – 2.40 respectively. Conclusively, the medicinal plants and spices demonstrated good potentials for reducing rumen methane production in vitro and may be subjected to further in vivo studies. Keywords: in vitro, spices, medicinal plants, methane production, ruminant