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Phytochemical research using medicinal plants has been instrumental in discovering new drug skeletons. Infectious disease management and treatment are made more difficult by the growing issue of antibiotic resistance. Two new derivatives were obtained by reacting with 3-bromo-1-propyne to derivatise trans-N-coumaroyltyramine (1), a natural isolate from Celtis zenkeri stem-bark that our research group previously reported. These are 7-(prop-2-yn-1-yloxy)-N-coumaroyltyramine (1a) and 7, 6'-di-(prop-2-yn-1-yloxy)-N-coumaroyltyramine (1b). Compounds underwent screening for antibacterial activity after being characterised using NMR, MS, IR, and UV-VIS spectroscopic techniques. As compared to the zone of inhibition of 20 ± 0.34 mm to 31 ± 0.29 mm of streptomycin, the 1a and 1b (10 ± 0.17 mm to 16 ± 0.68 mm) demonstrated potent inhibitions across all tested bacteria. Pharmacokinetic analysis of the compounds and Streptomycin® (a common antibacterial drug) are part of the in silico studies, along with molecular docking. The potency and drug-like qualities of new derivatives were demonstrated by the in vitro and in-silico investigations. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the roots of Allophylus spicatus (Sapindacea) led to the isolation of four compounds, namely cleomiscosin A (1), cleomiscosin C (2), scopoletin (3) and 3-oxotirucalla-7,24-dien-24-oic acid (4). The structures of the compounds were established by spectroscopic analysis: UV, IR, 1D and 2D NMR, EI-MS and HR-EI-MS and compared with the literature. These compounds are reported for the first time from the plant. The compounds showed potent antibacterial activity, marked inhibition against most of the tested bacterial strains: Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Salmonella typhi (ATCC 25923), Klebsiella pneumonia (ATCC 13883), Streptococcus faecalis (ATCC 29212) and Micrococcus luteus (ATCC 10240), with a zone of inhibition between 0.7±0.35 - 16±0.46 mm as compared with the zone of inhibition of Streptomycin (20±0.34 - 31±0.29 mm), a known antibacterial drug used as the standard. The antibacterial activity of the isolated phytochemicals could be responsible for the plant ethno-medicinal uses. [ABSTRACT FROM AUTHOR]

Blighia unijugata (Baker) and B. sapida (K.D. Koenig) (Sapindaceae) are forest trees widespread in Tropical Africa. They are used in folk medicine for the treatment of rheumatism, cardiovascular diseases, yellow fever, dysentery, and epilepsy. The essential oils of the air-dried leaves, stem bark, and roots of the plants were extracted using the hydrodistillation method and were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical method using a-tocopherol and ascorbic acid as standards. The insecticidal activity of the oils was investigated by determining the percentage mortality of the grain insects (Sitophilus zeamaise). Results showed that the yield of the colorless oils (% w/w) from the leaves, stem bark, and roots of the plants were 0.91%, 0.42%, and 0.34% for B. unijugata and 0.67%, 0.32%, and 0.48% for B. sapida, respectively. The most abundant compounds in B. unijugata leaves were pentadecanoic acid (14-methyl-, methyl ester) (38.34%), carbonic acid, propyl-en-2-yl undecylpropyl ester (36.79%), and 9-octadecanoic acid (Z)-methyl ester (24.86%). The stem bark was rich in 1,3-dimethoxybenzene (79.01%) while the root contained limonene (20.51%), trans-13-octadecanoic acid (16.74 %), and cis-vaccenic acid (9.50%). The leaf essential oil of B. sapida had hexahydrofarnesyl acetone (21.43%), phytol (20.45%), geosmin (16.258%), and a-ionone (8.271%) as the major constituents. The stem bark had cholesterol (38.66%) as the major constituent while the root contained nonanal (18.09%) and 4-cyclopropyl carbonyl tetradecane (11.6%). The antioxidant analysis revealed that B. unijugata root had 83.96% inhibition at 100 mg/ml, while B. sapida stem had 79.73% inhibition, better than a-tocopherol. No significant insecticidal activity was observed in the essential oils of the plants against S. zeamaise except for B. sapida stem which showed 50% toxicity to the maize weevils. However, the two plants can be the source of antioxidant agents against oxidative stress and related diseases. [ABSTRACT FROM AUTHOR]

A new iso-benzofuranone propanamide: 3-(3-oxo-1, 3-dihydroisobenzofuran-1-yl) propanamide (zenkeramide) (1) along with three known compounds: Trans-N-coumaroyltyramine (2), β-Sitosterol (3) and β-sitosterol-3-0-β-D-glucopyranoside (4) were isolated from the ethyl acetate fraction of the stem-bark of Celtis zenkeri Engl (Ulmaceae). The structure of the new compound was elucidated by extensive spectroscopic analysis. The compounds were examined for Urease Inhibitory Activity. Compounds 1 and 2 showed moderate activities (IC50 values (μM) of 42.3 ± 0.19 and 45.2 ± 0.55, respectively), while compounds 3 and 4 were potent inhibitors of the Jack bean urease (IC50 values (μM) of 20.3 ± 0.37and 27.6 ± 0.52, respectively), when compared to the standard inhibitor (thiourea- IC50 21.5 ± 0.47). The isolation of all the compounds from C. zenkeri and the urease activity of compounds 1 and 2 are reported for the first time. [ABSTRACT FROM AUTHOR]

Physalis angulata is an annual herb which has tremendous medicinal uses. The antioxidant activity of the whole plant extract of Physalis angulata was investigated using DPPH radical scavenging activity. Purified compounds were isolated using column chromatography method. Their structures were determined using various spectroscopic techniques. A new compound named as Squalen-1-ol, Phytol, squalene and α-tocopherol were isolated. These compounds were isolated for the first time from Physalis angulata. The extract of Physalis angulata gave a significant IC50 value of 0.77 mg/mL as compared with the standard ascorbic acid with IC50 value of 0.24 mg/mL. It can be correlated that the antioxidant activity of Physalis angulata could be attributed to the presence of α – tocopherol which is a known antioxidant. The presence of these compounds gives a further added pharmacological value to the plant. [ABSTRACT FROM AUTHOR]

Gakolanone (3',5'-digeranyl-2',4',6',3-tetrahydroxybenzophenone; 1), a novel benzophenone derivative was isolated from the hexane extract of Garcinia kola Heckel stem-bark along with three known 3-8' linked biflavonoids: 3',4',4'',5,5',7,7'-heptahydroxy-3,8'-biflavanone (2); 3',4',5,5',5'',7,7'-heptahydroxy-4-methoxy-3,8'-biflavanone (3) and 4',4'',5,5',7,7'-hexahydroxy-3,8'-biflavanone (4) from the ethanol extract. The compounds were characterized primarily using 1 D and 2 D nuclear magnetic resonance spectroscopy and mass spectrometry and by comparing with literature. The compounds were subjected to in-vitro alpha-amylase enzyme inhibitory assay using DNSA (3,5-dinitrosalicylic acid) reagent with acarbose used as the standard drug. All the compounds were found to show alpha-amylase inhibitory activities with IC50 of 21.4 ± 1.5, 9.9 ± 0.2, 15.3 ± 2.3, 12.9 ± 2.3 µg/mL respectively. All the compounds exhibited better alpha-amylase inhibitory activities than the standard drug, acarbose (IC50= 38.1 ± 8.3 µg/mL). [ABSTRACT FROM AUTHOR]

In West Africa and Nigeria in particular, many virgin plants are still waiting to be evaluated for their medicinal importance. Claims of plants with folk medicinal applications need to be evaluated and verified. Gomphrena celosioides (family - Amaranthaceae) is a weed grown in lawns and the biological activity of the extract had earlier been established. In the present study, the plant was collected, air dried, ground and soxhlet extracted with n-hexane and two compounds were isolated from the flakes that were recovered from the n-hexane extract on cooling. Column chromatography using 5% chloroform in n-hexane effected the separation. The structures of the isolated compounds were elucidated by spectroscopic analysis using IR, NMR (1H and 13C) and EI-MS. The compounds were found to be aurantiamide and aurantiamide acetate. This is the first report of isolation of these compounds in Gomphrena celosioides. [ABSTRACT FROM AUTHOR]

A new prenylflavanone dimer named bis-sigmodiol was isolated from Erythrina sigmoidea, along with six known constituents isobavachin, lupiwighteone, orientanol A, ergosta-4, 6, 8 (14), 22-tetraen-3-one, lupenyl acetate, and p-hydroxybenzoic acid. These known constituents have not been reported so far from E. sigmoidea. Their structures were elucidated by spectroscopic methods. [ABSTRACT FROM AUTHOR]

Free radicals are involved in the process of lipid peroxidation and play a cardinal role in numerous chronic diseases like cancer, coronary heart disease and ageing. Thus the ability to scavenge free radicals in order to minimize oxidative damage to living cells is very important. The hexane extract of Acalypha hispida (Burn F.) was screened for phytochemical constituents and was found to contain flavonoids, carbohydrates, phenols and alkaloids. Fractions obtained from chromatographic separation were screened for free radical scavenging activities using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and hydrogen peroxide. Out of the sixteen pooled fractions (S 1 -S 16 ) screened, compounds S 10 (91.8 %), S 11 (93.8 %), S 14 (92.5 %) and S 15 (91.4 %) at a concentration of 0.1 mg/ml had significant antioxidant activities when compared to the known antioxidant ascorbic acid (90.9 %). However, in the analysis using hydrogen peroxide, S 1 (99.5 %), S 9 (99.2 %), S 10 (95.4 %),S 11 (95.8 %) and S 15 (95.6 %) gave better activity than ascorbic acid (94.8 %), while only S 1 and S 9 were more effective than butylated hydroxylanisole (98.9 %) and α-Tocopherol (99.1 %) at the same concentration. The cytotoxicity analysis using the Brine Shrimp lethality test gave LC 50 values greater than 1000 μg/ml for some of the fractions indicating very low level of toxicity. The better scavenging activity of A. hispida could be linked to the presence of secondary plant products like flavonoids and phenols, which have the ability to scavenge hydroxyl radicals, superoxide anions and lipid peroxy radicals.