Coordination compounds of 4-hydroxy-3-nitro-2H-chromen-2-one and their mixed ligand complexes with aminoethanoic acid and pyrrolidine-2-carboxylic acid were synthesized by the reaction of Cu(II) and Zn(II) salts in molar ratio 1 : 2 for the coumarin complexes and 1 : 1 : 1 for the mixed ligand complexes, in basic media. The compounds formed were characterized using infrared, Uv-vis spectrophotometric analyses, mass spectrometry, magnetic susceptibility measurements, and EDX analyses. It was concluded that 4-hydroxy-3-nitro-2H-chromen-2-one coordinated as a monobasic ligand for all the complexes; it also coordinated via the carbonyl moiety in the case of the Cu(II) mixed ligand complexes. Similarly it was proposed that the amino acids also coordinated in a bidentate fashion via their amino nitrogen and carboxylate oxygen atoms. The synthesized compounds were screened for their antimicrobial and cytotoxic activities. The complexes exhibited marginal antimicrobial activity but good cytotoxic activity.

Objective: Vigna unguiculata ssp. dekindtiana (L.) Walp is used in traditional practice to treat depression-like disorders in some communities of Southwest Nigeria. This study investigated the antidepressant-like effects of the aqueous fraction of the dried aerial parts of V. unguiculata ssp. dekindtiana (AFVU). Methodology: AFVU was evaluated for antidepressant effect on the force-swimming test (FST), tail suspension test (TST) and locomotor activity (LC) in the open field test (OFT) using mice; and its probable neural mechanism(s) investigated using various receptor antagonists. Elemental composition (EC) and phyto-constituents of AFVU were analyzed using standard methods. Results: The AFVU (600 and 800 mg/kg, p.o.) significantly (p<0.05) decreased the immobility time of mice in FST and TST without significant (p<0.05) effect on LC, suggesting that its antidepressant-like effect is specific; anti-immobility effect of AFVU was significantly (p<0.05) blocked by intraperitoneal injection of prazosin (62.5 µg/kg), yohimbine, (1 mg/kg), cyproheptadine (3 mg/kg), sulpiride (50 mg/kg), methylene blue (10 mg/kg) and L-NNA (10 mg/kg) suggesting adrenergic, serotonergic, dopaminergic and nitergic pathways. The EC assured its safety; while phenols and alkaloids were the most abundant phytoconstituents in AFVU. Conclusion: This study concluded that AFVU possessed antidepressant-like effects which may be mediated through multiple receptor pathways.

The study investigated the antioxidant and antimicrobial activities of some West African hemi-parasitic plants, which comprised Tapinanthus bangwensis (TB), Tapinanthus globiferus (TG) and Globimetula braunii (GB), used in Nigerian ethnomedicine for the management of skin and other microbial infections. This was with a view to determining the most active plant extract and fraction. The leaf and stem of each plant was separately air-dried, powdered and macerated in ethanol-H20 (8:2). The extracts were subjected to in vitro antioxidant tests such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), Fe2+ chelating ability (FIC) and total antioxidant capacity (TAC) assays, with L-ascorbic acid, quercetin and ethylenediaminetetraacetic acid (EDTA) as positive controls. The antimicrobial test was carried out using micro-broth dilution method against reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, where ciprofloxacin and ketoconazole were the positive controls. An activity-guided fractionation approach was adopted in the study. The most active GB leaf extract was fractionated to obtain n-hexane, dichloromethane, ethylacetate, n-butanol and aqueous fractions, and were subsequently tested. The results showed that the extract of GB leaf demonstrated the highest bioactivities with inhibitory concentration (IC50) of DPPH at 31.21±1.11 µg/mL, FRAP value of 109.30±0.76 mg AAE/g, TAC value of 178.15±3.54 mg AAE/g and MIC of 5.0 – 10.0 mg/mL. The Ethylacetate fraction of GB leaf demonstrated the highest bioactivities, which were four-times, thrice and twice better than its GB leaf extract in the DPPH, TAC and antimicrobial studies respectively. The EtOAc fraction (IC50 = 8.58±1.39 µg/mL) was comparable (P > 0.05) in antioxidant activity with quercetin (IC50 = 7.72±0.88 µg/mL). The EtOAc fraction also exhibited broad-spectrum antimicrobial activity with inhibitory concentration of 1.25 mg/mL against MRSA and C. albicans. In conclusion, the extract of G. braunii leaf demonstrated considerable bioactivities and the moderately polar EtOAc fraction was the most active fraction; hence, validates the folkloric use G. braunii leaf as a remedy for microbial infections.

Objective: The mechanism of ethanol-induced gastrointestinal mucosal lesions is known to include direct damage to mucus synthesis. The present study histochemically evaluated the activity of mucus secreting cells and determined the concentration of nitric oxide (NO) in ethanol injured pylorus and duodenum of rats pretreated with ethanol extract of Moringa oleifera (MO) leaves. Methods: Male adult rats were randomly assigned into five groups: group A served as control; group B received single dose of 5 ml/kg ethanol orally; group C received 200 mg/kg MO only orally for five days; group D and E received MO at 200 mg/kg and cimetidine at 100 mg/kg orally for five days, respectively, and then ethanol was administered at 5 ml/kg orally on the 6 th day to these groups. Results: Ethanol significantly reduced NO concentration in pylorus, and this was attenuated with MO pretreatment. Pretreatment with both MO and cimetidine significantly attenuated the hemorrhagic injuries induced by ethanol. Pretreatment with MO increased activity of mucus secreting cells compared to ethanol only group. Conclusion: The present study demonstrated that the antiulcer activity of Moringa oleifera may be attributed to preservation of mucus secreting cells and maintenance of endogenous NO concentrations in ethanol injured gastroduodenal tissues.

Heliotropium indicum L. has been shown to be very important in traditional healing medicine. However, many reports have indicated that the toxicity is not unconnected with pharmaceutical properties. This study therefore investigated the cytotoxic, genotoxic and biotoxic activities of methanolic leaf extract of H. indicum using Brine Shrimp lethality assay. The results revealed that the leaf extract of H. indicum showed lethality against the Brine Shrimps nauplii. The highest mortality was recorded at a concentration of 1000 μg/ml. The LC50 value of the Brine Shrimps mortality of the extract was recorded to be 461.04±10.02 μg/ml. In addition, the extract inhibited mitotic division in A. cepa root meristematic cells. The mitotic index was reduced from 59.99% in the control to 2.2% at 1000 μg/ml of the leaf extract. Chromosomal aberrations were observed at different concentrations. These include sticky chromosomes at metaphase and anaphase, chromosome breakage, degenerated and disoriented chromosomes at metaphase plate. It can be concluded from this present study that methanolic leaf extract of H. indicum was cytotoxic and genotoxic to Brine Shrimps and A. cepa cells respectively. Hence, caution should be exercised with respect to the consumption of H. indicum leaf in any form. © 2020 International Formulae Group. All rights reserved. Keywords: Mitotic index, chromosome aberrations, Brine Shrimps Lethality assay, Allium cepa assay, leaf extract