Nigerian Journal of Natural Products and Medicine

Synthesis and bio performance of encapsulated antimalarial co-artemeter in mesoporous nanosilica vesicle

O.P. Oladipo — 2024-11-27

Nano carrier vessel is a new approach for ultimate delivery of drugs. This research work synthesised Mobile Composition of Matter (MCM-41) [1] for loading of two antimalarial drugs: MCM-41Artemether(ATM) [2] and MCM-41Lumefantrine(LFT) [3] under varying time, pH and temperature effects. FT-IR spectra depict major functional groups of the silanol group (Si-OH) and silaxone (Si-O) at 3450 and 964 cm^-1, respectively for the 1, while 2 and 3 exhibited only functional groups similar to the parent silica core. 1 had average pore diameter of 5.16 nm while 2 and 3 pore sizes decreased to 4.04 and 3.16 nm, respectively due to the adsorption of the drugs. Morphology of 1 is spherical while 2 and 3 have distorted rod-like shapes attributed to the drugs impregnation as obtained from SEM. The optimal loading conditions of 2 at pH 3.5 ambient temperature, and 3 h gave drug loading capacity (DLC) of 79% and entrapment efficiency (EE) of 65% compared to 3 with DLC of 77% and EE of 50% attributable to the size effect. For the in vitro kinetic release of 2 at 1 h, ambient temperature and pH 3.5 gave 61.4% optimal release, which was very much higher compared to 3 of 7.4% at 0.5 h with other conditions similar. The in vivo measurement of 1 showed better bio performance for Plasmodium berghei NK65 parasite clearance in infected mice on the third day compared to 2 or 3 for nanodrugs and the individual parent drugs. This study confirmed the suitability of 1 for better delivery of ATM and LFT antimalarial drugs.

Hypolipidaemic and hepatoprotective effects of six Nigerian antidiabetic plants

M. D. Ayoola — 2024-11-27

The methanol extracts of the leaves of Hoslundia opposita (HOL), Cleistopholis patens (CPL), Dioscoreophyllum cumminsii (DCL), Olax subscorpioidea (OSL) and Plumbago zeylanica (PZL), as well as whole plant of Senecio biafrae (SBW) that have been earlier reported for their antidiabetic activities were evaluated in this study for their hypolipidaemic and hepatoprotective potentials with a view to establishing their possible ability to reduce the complications of diabetes mellitus. Effects of the methanol extracts of these plants on biochemical parameters, such as, total cholesterol, triglycerides, high-density lipoprotein-cholesterol, were estimated in alloxan-induced diabetic rats. Histopathological examinations of pancreases and livers of rats were carried out at 400 mg/kg for leaves of H. opposita, O. subscorpioidea, C. patens and S. biafrae whole plant, while D. cumminsii and P. zeylanica leaves at 200 mg/kg. Results obtained were expressed as mean ± SEM using GraphPad Prism 7 (GraphPad Software Inc., La Jolla, CA, USA). Analysis of Variance (ANOVA), followed by the Dunnett multiple comparison tests were used while p < 0.05 was taken as significant. All the six plants' extracts significantly reduced total cholesterol and triglycerides levels and increased the highdensity lipoprotein-cholesterol levels of the diabetic rats. Leaves of P. zeylanica and C. patens being the most active extracts, reduced cholesterol level from 2.3 to 1.0 and 0.8 mMol/L, respectively and reduced triglyceride from 0.6 to 0.9 mMol/L. The extracts also caused a pronounced reduction in vacuolation within the islet cells with the evidence of regeneration of the cells coupled with reduction in fibrosis, indicating possible reversal of pancreatic lesions in the pancreases of the alloxan-induced diabetic rats. The methanol extracts of these six Nigerian antidiabetic plants demonstrated hypolipidaemic and hepatoprotective effects in alloxan-induced diabetic rats and showed evidence of regeneration of the pancreatic cells.

Isolation and characterisation of a novel xanthone with board-spectrum antibacterial activity from the roots of Allanblackia floribunda oliver (guttiferae)

P. A. Idowu — 2024-11-27

The increasing antimicrobial resistance of pathogens to existing therapeutic agents is currently a global health challenge, which led
us to a bioassay-guided investigation of Allanblackia floribunda Oliver (Guttiferae) roots for new antimicrobial constituents. The roots were extracted successively in Soxhlet with hexane, ethyl acetate and methanol. Isolation from the ethyl acetate extract was done using an open Column Chromatography, and Preparative Thin Layer Chromatography for purification. Structural elucidation was done using extensive 1-D and 2-D NMR, IR, MS data and physico-chemical properties. Antimicrobial activity and Minimum Inhibitory Concentration (MIC) were determined using agar-well diffusion and broth dilution methods, respectively. The root extracts, pooled fractions and isolated compound were tested on bacteria including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Bacillus subtilis ATCC 6633 and clinical isolates of Salmonella typhi. The root extracts and pooled fractions (Al , Al A, F , A and A ) were active on the test bacteria with zones of 1 2 19 18 100 inhibition ranging from 12 to 20 mm. Fraction Al A showed highest consistent activity comparable to gentamycin standard and 2 yielded compound Al , a novel xanthone: 1, 2, 3, 4, 5, 8-hexahydroxy-9H-xanthen-9-one. The MICs in mg/mL of Al on the test 2 2 organisms are: S. aureus (0.75), E. coli (1.25), P. aeruginosa (1.13), B. subtilis (0.15) and S. typhi (0.08). These results justify the ethnomedicinal use of the root bark of Allanblackia floribunda in the treatment of diseases and the isolated xanthone has a high potential to become a chemotherapeutic agent for bacterial infections.

In vitro membrane stabilisation and free radical scavenging activities of Entandrophragma utile (dawe and sprague) sprague stem bark and Uvaria afzelii Scott-Elliot root

Augustine Ebuka Mbanu — 2024-11-27

Ethnobotanical surveys indicated that Entandrophragma utile and Uvaria afzelii are used for the treatment of several inflammatory diseases. However, there is no scientific validation of the traditional claims of the anti-inflammatory properties of the plants. Thus, this study was carried out to assess the anti-inflammatory potentials of the extracts of E. utile and U. afzelii and validate the ethnomedicinal claim of the plants in the treatment of inflammatory diseases. Membrane stabilisation activity, free radical scavenging activity and phytochemical screening were carried out on the two plants. The inhibition of lysis by the crude extract and fractions of E. utile stem bark (EUSB) and U. afzelii root (UAR) ranged from 6.21–78.80 and 4.17–86.05%. At the lowest tested concentration (0.125 mg/mL), the best inhibition activities of 44.51±2.39 and 27.02±0.80% were by the ethyl acetate fractions of EUSB and UAR, respectively. Similarly, at 1.5625 μg/mL, the ethyl acetate fractions of EUSB and UAR proved active for free radical scavenging with activities of 48.47±0.51 and 87.24±0.21%, respectively. The results from the membrane stabilisation and free radical scavenging activities could support the ethnomedicinal claim on the use of Entandrophragma utile stem bark and Uvaria afzelii root in the treatment of inflammatory diseases in Southwestern Nigeria.

Pharmacognostic evaluation and development of HPLC fingerprint for standardisation of Waltheria indica l. (Malvaceae)

Y.M. Oyetunde — 2024-11-27

Studies have supported ethnobotanical claims on Waltheria indica L. Malvaceae. However, its standardisation parameters are yet to be defined. This study conducted pharmacognostic evaluation and High-Performance Liquid Chromatography (HPLC) to develop standards for Waltheria indica. The plant was collected, identified, and authenticated. The morphological and anatomical characters were studied by organoleptic evaluation and microscopy, respectively. Physicochemical constants and phytochemical contents were determined. Chromatographic fingerprints of the leaf, stem, and root powders were obtained, and peaks were identified and quantified based on phenolic standards. Physical characters of Waltheria indica were described. Photomicrographs showed abundant stellate trichomes in leaves and stem of the plant. The vascular bundles were arranged in amphicribral form with endarch xylems. The adaxial surface of the leaf has straight epidermal cells with anisocytic and diacytic stomata, while the abaxial surface has wavy epidermal cells with only anisocytic stomata. The alcohol and water extractives values of leaf, stem, and root are (22.2%, 11.8%, and 14.44%) and (15.47%, 7.6% and 7.33%) respectively. Moisture content (6.62%, 2.78%, and 3.63%) and ash values (7.77%, 2.73%, and 2.33%) were within pharmacopoeia limits. Steroids, terpenoids, saponins, tannins, phenols, flavonoids, cardiac glycosides, anthraquinone, and alkaloids were present in all plant parts. Chromatographic fingerprints of plant parts showed unique peaks for phenolic standards. All plant parts had 4-hydroxybenzoic acid, epigallocatechin gallate, and epicatechin, with epicatechin most abundant in the leaf (1,371,061 ng/g). The standardisation parameters developed would be helpful in monograph preparation for Waltheria indica.

Antipsychotic activity of Aframomum melegueta (roscoe) K. Schum (Zingiberaceae) and Bidens pilosa l. (Compositae) in male mice

Victoria Onosemudiana Eigbe — 2024-11-27

Mental disorder features unhealthy situations such as sleep disturbance, social withdrawal and impaired role functioning, all of which are treated with herbal formulations, by traditional healers. Aframomum melegueta and Bidens pilosa are medicinal plants applied traditionally to treat psychosis. Hence, this study investigated the antipsychotic effect of the two plants in ketamine induced psychosis in mice. Pulverised plant samples consisting of Aframomum melegueta seeds and leaves, and stem of Bidens pilosa were macerated in absolute methanol for 72 h. Extracts were evaluated in mice for hyper-locomotion in open field and stereotype behaviour in transparent chamber models. Statistical analysis was done using one-way ANOVA at p < 0.05. Aframomum melegueta seeds, and B. pilosa leaves at 500 mg/kg and B. pilosastem at 250 mg/kg, decreased hyperactivity in mice, when compared to the negative control group (ketamine only). Furthermore, the highest dose (500 mg/kg) of Aframomum melegueta seeds, B. pilosa leaves and 250 mg/kg of B. pilosastem gave total tranquilising effect at 60 min into the experiment. Findings from this study revealed that seeds of Aframomum melegueta, and the leaves as well as stem of Bidens pilosa possess constituents responsible for the treatment of psychosis. This in turn justifies the traditional use of both plants in the treatment of mental illness. Different ratios of both plants under study may be combined as formulations and tested in future research, as a step towards drug development.

Evaluation of antioxidant and antacid activities of Globimetula braunii and Parquetina nigrescens extracts

Basirat Atinuke Raji — 2024-11-27

Natural products are one of the best sources of therapeutic-based compounds for the treatment of peptic ulcer, which denotes open sores on the lining of the stomach or small intestines. Globimetula braunii (Family Loranthaceae), Microdesmis puberula (Family Pandaceae) and Parquetina nigrescens (Family Apocynaceae) have been documented for various medicinal uses, including the traditional treatment of peptic ulcer in Nigeria. This study aimed to assess the antioxidant and antacid properties of Globimetula braunii, Microdesmis puberula and Parquetina nigrescens. The plant samples were collected, identified and authenticated. The samples were allowed to air dry, pulverised and then extracted using methanol. The extracts were assessed for antioxidant (2,2-diphenyl-1-icrylhydrazyl, DPPH), free radical scavenging activity, total phenolic content (TPC), total flavonoid content (TFC), and antacid activity. The total phenolic content was highest in G. braunii, followed by P. nigresens and then M. puberula with values of 6.74 mg GAE/g, 3.35 mg GAE/g and 0.56 mg GAE/g, respectively. The crude extract of G. braunii showed the highest radical scavenging activity below 50% with IC₅₀ value of 53.73. Globimetula braunii methanol extract (250 mg/250mL) showed the highest artificial gastric acid neutralising activity by raising the pH of the artificial gastric acid from 1.2 to 1.80±0.04, which is like the standard NaHCO₃ (100 mg/250mL) that raised the pH of the artificial gastric acid from 1.2 to 1.78±0.03. The results from this study support the ethnomedicinal claims that plants can be used in the management of peptic ulcer, and these plants could serve as sources of lead compounds to produce natural antacids.