Nigerian Journal of Natural Products and Medicine

Isolated compounds from Alternanthera dentate (Moench) stuchlik leaf extracts and their antimicrobial effects

B.O. Olorungbeja — 2023-09-14

Alternanthera dentata leaf extracts are used to treat infectious diseases such as skin diseases in folk medicine. This study isolated and evaluated activities of its bioactive compounds. A. dentata crude leaf extract obtained from 80% methanol was partitioned with n-hexane, dichloromethane, ethyl acetate and n-butanol respectively. The four fractions obtained were assayed for their antimicrobial activities against reference and clinical bacteria and fungi strains using agar dilution and micro-well dilution methods. Activity directed fractionation of the ethyl acetate fraction afforded two compounds and their structures elucidated using NMR (1D and 2D) spectroscopic data. The results of the antimicrobial assays showed that the ethyl acetate fraction had the best activities. This fraction afforded two compounds identified as 7-O-flavone glycosides: chrysoeriol-7-O--glucoside (1) and apigenin-7-O--glucoside (2) from the spectroscopic data. The compounds are reported from A. dentata extracts for the first time. Compound 1 showed moderate to weak antimicrobial activities against some of the selected organisms though better than compound 2. It had MIC of 0.63 mg/mL against Bacillus subtilis (ATCC 1263), Escherichia coli (ATCC 700727) and clinical strain of Methicillin Resistant Staphylococcus aureus (MRSA) and 2.50 mg/mL against Candida pseudotropicalis. Structure Activity Relationship Studies (SARS) of the antimicrobial properties of compounds 1 and 2 indicated that the relative potency of compound 1 when compared with compound 2 is due mainly to the presence of 3' methoxylation of its ring B. This study concluded that, of the two compounds isolated, chrysoeriol-7-O--glucoside (1) contributes more to the antimicrobial activities of the plant.

An overview of ethnobotany, phytochemistry and pharmacological action of selected medicinal plants

R. Nithya — 2023-09-14

The plants Acorus calamus, Withania somnifera, Clitoria ternatea, Centella asiatica, Wedillia chinensis, Cissus quadrenqularis are the commonly used plants in South India in day-to-day life as part of food as well as to treat many diseases as traditional medicine, Cassytha filiformis is a parasite herb which is used in many parts of the world for traditional medicine. Like food, these are consumed for immunity, energy, vitamin and mineral sources as well as home remedies for certain health conditions. As a medicine, these plants have many Phytochemical constituents which are the reason for their biological activity. Various secondary metabolites were found from these plants including Alkaloids, Terpenoids, Saponins, Tannins, Flavonoids, etc and multiple biological activities were established by in-vivo and in vitro studies so far. In the future also, studies need to be carried out to bring effective medicines to cure various new diseases in humans.

In vitro anti-ulcer activity and isolation of 5 – hydroxymethyl furan – 2 – carbaldehyde and palmatine from Curculigo pilosa (schumach. & thonn.) Engl.

Idayat Adeola Akinwumi — 2023-09-14

Curculigo pilosa (Schumach. & Thonn.) Engl. (Hypoxidaceae) is commonly used in traditional medicine in the management of several ailments. The rhizome is traditionally used for treating gastrointestinal diseases. The present study focuses on the in vitro anti-ulcer activity of Curculigo pilosa and isolation of compounds. Powdered rhizomes of the plant were extracted with methanol. The extract was successively partitioned into n-hexane, dichloromethane, ethyl acetate (EtOAc), n-butanol and aqueous fractions. Fractions were screened for antacid and urease inhibitory activities using titrimetric method and urease inhibitory assay with sodium bicarbonate and acetohydroxamic acid used as standards. Compounds were isolated from active fractions of the plant using chromatographic techniques. Structures of isolated compounds were elucidated using spectroscopic techniques. Only compound 1 was evaluated for urease inhibitory and antacid. Data were analyzed using one-way ANOVA and Dunnet multiple comparison test at P 0.05. The n hexane and aqueous fractions were active in comparison with standard drug acetohydroxamic acid for urease inhibitory assay, while the ethyl acetate and n butanol fractions gave good antacid activities which were comparable to the activity exhibited by sodium bicarbonate. 5-Hydroxymethyl-2-furancarbaldehyde (1) and Palmatine (2) were isolated for the first time in Curculigo pilosa and new to family Hypoxidaceae. 5-Hydroxymethyl-2-furancarbaldehyde (1) displayed excellent antacid activity. Few compounds have been isolated from this plant despite the numerous reported biological activities. The antacid and the urease inhibitory activities are reported for the first time.

Mineral composition and antioxidant analysis of the leaves of monkey’s potato (Solenostemon monostachyus (P. Beauv) Briq)

P.C. Chijindu — 2023-09-14

This study investigated the mineral composition and antioxidant potentials of the leaves of Monkey’s Potato (Solenostemon monostachyus (P. Beauv.) Briq.) The leaves of S. monostachyus used in this study were collected from the Biological garden at College of Education, Warri, Delta State. Standard methods were employed to determine the composition of minerals and antioxidant capacity of S. monostachyus. The results from the mineral analysis revealed that calcium had the highest composition (2.64 ± 0.01 mg/kg) followed by manganese (1.74 ± 0.00 mg/kg) and zinc (1.02 ± 0.00 mg/kg). While the composition of iron, copper, nickel and lead were 0.83 ± 0.01 mg/kg, 0.64 ± 0.01 mg/kg, 0.04 ± 0.01 mg/kg and 0.02 ± 0.00 mg/kg respectively. Results from the antioxidant analysis (DPPH Assay) revealed a significant difference in the radical scavenging activity of Solenostemon monostachyus and Ascorbic acid, with Solenostemon monostachyus having a significantly higher DPPH radical scavenging activity with an IC₅₀ value of 0.25ug/ml than Ascorbic acid with an IC₅₀ value of 0.03ug/ml. The total antioxidant capacity of Solenostemon monostachyus was 0.6 ± 0.01 (AAE/g) indicative of strong antioxidant activity. These minerals and antioxidant properties may account for the various health benefits of Solenostemon monostachyus. Based on the result obtained, it is therefore recommended that S. monostachyus should be cultivated for its various nutritional and antioxidant potentials rather than being treated as a weed.

Pharmacognostic and physicochemical evaluation of the leaf and root of Uvaria chamae (P. Beauv.) annonaceae

Awodayo O. Adepiti — 2023-09-14

The ethnomedicinal use of Uvaria chamae (P. Beauv) Annonaceae as an antimalarial has been scientifically justified. This study was carried out to determine the pharmacognostic and physicochemical characters of its leaf and root with a view to establishing pharmacopoeial parameters for their quality control. The fresh leaf and root of U. chamae, collected and authenticated in the IFE Herbarium, Obafemi Awolowo University, Nigeria, were preserved in ethanol (50%) while some were oven-dried and powdered. Organoleptic evaluation of the fresh samples and microscopy of the powders were carried out according to standard methods. Transverse section and surface preparation of the fresh leaf as well as radial and tangential longitudinal sections of the root were carried out. Physicochemical properties such as moisture content, ash and extractive values were determined. The methanol extracts of the powders were subjected to HPLC-MS analysis. The transverse section of the leaf revealed a dorsiventral midrib and striated cuticle. On the abaxial surface, paracytic stomata were observed but the adaxial surface lacked stomata while the vascular bundle was of the collateral type. The root of U. chamae had prismatic calcium oxalate crystals and tyloses. The physicochemical results were as follow: the total ash (9.6 & 9.7%), loss on drying (8.8 & 8.1%), alcoholextractive value (3.5 & 0.8%), water-extractive value (4.5 & 1.3%) for the leaf and root, respectively. Flavonoids such as pinocembrin and chamanetin were identified in the root. The study revealed pharmacognostic and chemical profiles that may aid the identity, and therefore, quality control of U. chamae.

Antisickling activity-guided fractionation of some plants used for the management of sickle cell disease in southwest Nigeria

J.M. Agbedahunsi — 2023-09-14

The study evaluated the antisickling activities of some plants used in the Southwestern Nigeria ethno-medicine for the management of sickle cell disease (SCD), with a view to determining the most active plant extract and fraction. A semi-structured questionnaire was administered to two hundred and ten (210) respondents, which comprised traditional medical practitioners, herb sellers and community elders. Aqueous extracts of the plants with high fidelity levels alongside the positive controls (vanillic acid and p-hydroxybenzoic acid) were tested in vitro against the sickled erythrocytes, using the inhibitory and reversal assay methods. The active extracts were solvent- partitioned into petroleum spirit, ethyl acetate and aqueous fractions, and subsequently bioassayed. A total of 166 plants were mentioned as being used for the management of SCD within the zone, among which 27 plants were selected. Six of the selected plant extracts demonstrated remarkable antisickling activities. The aqueous extracts of Moringa oleifera leaf (MOL), Alchornia laxiflora leaf (ALL), Kigelia africana fruit (KAF), Olax subscorpioidea leaf (OSL), Pyrenacantha staudtii leaf (PSL) and Parquentina nigrescense leaf (PNL) demonstrated 88.0, 86.2, 76.2, 75.8, 54.4 and 52.2% inhibitory activities respectively, while the reversal activities were 76.9, 65.3, 75.5, 66.6, 52.4 and 66.0% respectively. The ethyl acetate fraction of MOL and KAF (4 mg/mL) demonstrated 94.6 and 87.2% inhibitory activities, and 94.7 and 81.4% reversal activities respectively. The mode of activity of KAF was by membrane stabilisation with 81.1% activity. Silica gel column purification, followed by preparative thin-layer chromatography of the ethyl acetate KAF fraction afforded 5 bands, M₁ – M₅ . At 4 mg/mL, band M₂ demonstrated the highest activity with 78.9% inhibitory and 70.8% reversal, and also showed strong free radical scavenging property. The findings validated the ethnomedicinal use of the six listed plants, especially M. oleifera leaves and K. africana fruits for the management of SCD and identified the ethyl acetate fractions of both plants to contain the putative compounds.

Nigerian Journal of Natural Products and Medicine

Isolated compounds from Alternanthera dentate (Moench) stuchlik leaf extracts and their antimicrobial effects

An overview of ethnobotany, phytochemistry and pharmacological action of selected medicinal plants

In vitro anti-ulcer activity and isolation of 5 – hydroxymethyl furan – 2 – carbaldehyde and palmatine from Curculigo pilosa (schumach. & thonn.) Engl.

Mineral composition and antioxidant analysis of the leaves of monkey’s potato (Solenostemon monostachyus (P. Beauv) Briq)

Pharmacognostic and physicochemical evaluation of the leaf and root of Uvaria chamae (P. Beauv.) annonaceae

Antisickling activity-guided fractionation of some plants used for the management of sickle cell disease in southwest Nigeria