In vitro antiplasmodial, cytotoxic and antioxidant effects, and phytochemical constituents of eleven plants used in the traditional treatment of malaria in Akwa Ibom State, Nigeria

Purpose: To evaluate the antiplasmodial effects of eleven plants (Bombax buonopozense, Carica papaya, Anthocleista djalonensis, Milicia excelsa, Heterotis rotundifolia, Homalim letestui, Starchystarpheta cayennnensis, Ocimum gratissimum, Cleistopholis patens, Chromolaena odorata and Hippocratea africana) reportedly used in the treatment of malaria in Akwa Ibom State of Nigeria. Methods: Phytochemical analysis was done by standard methods, while in vitro antiplasmodial evaluation was carried out using Plasmodium falciparum chloroquine-sensitive and chloroquineresistant strains using lactate dehydrogenase (pLDH) assay.  Cytotoxicity test was undertaken by MTT assay on LLC-MK2 cells and the concentration killing 50 % of the cells (CC50) was calculated.Antioxidant activity of the ethanol extract was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Results: Milicia excelsa, Heterotis rotundifolia and Chromolaena odorata had moderate antiplasmodial activity. Ocimum gratissimum and Hippocratea africana were weakly active. Milicia excelsa showed a considerable level of cytotoxicity, while Bombax buonopozense exhibited moderate cytotoxicity. Bombax buonopozense (95.3 %) and Ocimum gratissimum (92.0 %) exhibited high DPPH scavengingeffect comparable to Vitamin C (98.7 %). There was a significant correlation (p < 0.05) between DPPH inhibition and the total phenolic contents of the eleven plants studied (r2 = 0.6616), between DPPH inhibition and flavonoids (r2 = 0.3553), between antiplasmodial activity and saponin content (r2= 0.3992), and between the two antiplasmodial evaluation assay methods (r2 = 0.614).Conclusion: The results of this work provide some justification for the use of Milicia excelsa, Heterotis rotundifolia, Chromolaena odorata, Ocimum gratissimum and Hippocratea africana in the treatment of malaria. Keywords: Antiplasmodial, Antioxidant, Cytotoxicity, Phytochemicals, Antimalari

Isolation and characterization of antioxidant constituents of the fruit of Telfairia occidentalis Hook F (Cucurbitaceae)

Purpose: To evaluate the antioxidant property of the fruit of Telfairia occidentalis and isolate the components responsible for the antioxidant activity.Methods: The fruit pericarp was macerated with methanol and the extract obtained successively partitioned with n-hexane, dichloromethane and ethyl acetate. The in vitro antioxidant activity of the extract and fractions was evaluated using 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging, reducing power, nitric oxide scavenging, total antioxidant and hydrogen peroxide scavenging assays. The n-hexane fraction, which had the highest DPPH scavenging and total antioxidant activities, was subjected to column and thin layer chromatography to isolate the components. The isolated compounds were identified by ultraviolet-visible (UV), nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy and mass spectrometry.Results: Among the fractions tested, n-hexane had the best total antioxidant activity of 99.44 % at 20 mg/ml (p < 0.05) compared to ascorbic acid at 99.71 % of 20 mg/ml. This fraction also had the highest DPPH radical scavenging activity of all the fractions (p < 0.05) at all test concentrations. For nitric oxide scavenging activity, the whole extract, and the chloroform and aqueous fractions exhibited activity ranging from 92.29 to 97.66 % compared to 98.93 % for ascorbic acid. The hydrogen peroxide scavenging activity of the extract and fractions ranged from 92.60 to 96.23 % compared with of the standard, ascorbic acid (101.68 %). The major components of the n-hexane fractions were α- amyrin and β-amyrin.Conclusion: The fruit pericarp of Telfairia occidentalis possesses good DPPH radical scavenging activity. This is the first time the antioxidant activity of the fruit (pericarp) and the presence of α- and β- amyrins in Telfairia occidentalis have been reported.Keywords: Telfairia occidentalis, Fluted pumpkin, Amyrin, Antioxidant

Changes in Some Pharmacokinetics Parameters of Chloroquine by Gnetum Africana Maced

Abstract Effect of Gnetum africana on the pharmacokinetic parameters of chloroquine was investigated. Chloroquine phosphate (200 mg/Kg) was concurrently administered to overnight fasted albino rats. Blood samples were collected 15, 30, 60, 120, 240 and 480 minutes after administration through cardiac puncture. Serum concentration of chloroquine was evaluated spectrophotometrically. The results indicated that the extract significantly decreased Cmax (9.17%), Ka (3.06%), Ke (45.38%), C l (48.46%) and AUC ( 0-8 ) (16.90%). The extract also increased the values of t 1/2 (83.11%), t max (100.00%). The LD50 of the extract was 5.25 g/Kg. Phytochemical screening revealed the presence of steroids, tannins, flavonoids and traces of phlobatanins and alkaloids. Proximate and elemental analyses showed that the plant contained Sodium (26.37 + 0. Energy (407.80 Kcal). The results of this work showed that concurrent administration of the extract of Gnetum africana affected some of the pharmacokinetic parameters of chloroquine. Malaria patients on chloroquine therapy should therefore be advised to beware of consuming Gnetum africana

Synthesis of some esters of cinnamic acid and evaluation of their in vitro antidiabetic and antioxidant properties

Purpose: To synthesize various ester derivatives of cinnamic acid and to evaluate their in vitro antidiabetic and antioxidant properties. Methods: Esters of cinnamic acid were synthesized by refluxing the parent compound (cinnamic acid) with different alcohols using concentrated sulphuric acid as a catalyst. Physicochemical analyses (solubility, boiling point, refractive index) and spectrophotometric analyses (ultraviolet-visible spectroscopy (UV-VIS), Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectroscopy (GC-MS)) were carried out on the synthesized products. The antioxidant inhibitory property, uptake of glucose by yeast, and haemoglobin glycosylation of the synthesized products were also evaluated using standard methods. Results: The identities of methylcinnamate, ethylcinnamate, propylcinnamate, 2-propylcinnamate, butylcinnamate and 2-butylcinnamate were confirmed, at m/z ratios of (131,103,77 and M+ of162), (131,103,77 and M+ of 176), (147,103,77and M+ of 190), (147,103,77 and M+ of 204), (143, 103, 77 and M+ of 190), and finally (147,103,77 and M+ of 204) respectively. FT-IR results revealed the following important bonds for the synthesized compounds: C=O, C-C, C-O, C=H, C-H and adjacent H. The results for glucose uptake by yeast and of haemoglobin glycosylation test indicate that all the products facilitated the transport and detachment of glucose at varying concentrations, respectively. The DPPH scavenging activity of propylcinnamate, 2-butylcinnamate and methylcinnamate with the absorbance of 63.06, 56.85 and 53.06 at 50 μg/mL - 250 μg/mL, respectively, recorded the highest values when compared with the control (ascorbic acid). Conclusion: The results reveal that the six ester derivatives of cinnamic acid exhibit a certain degree of antidiabetic activity by facilitating the uptake of glucose by yeast and reducing glycation of haemoglobin; thus, showing a reasonable level of inhibition against free radicals

Direct Detection of Groundwater Accumulation Zones in Saprock Aquifers in Tectono-Thermal Environments

Some vertical electrical sounding (VES) data from tectono-thermal environments usually plot anomalously on a VES curve, thereby distorting the curve trend at the points of their occurrence. These datasets usually plot noisily in the form of a sudden rise and drop in electrical resistivity values. They constitute abnormal datasets that are usually deleted to recover trends and consequently develop confidence in both the datasets and the modelling and interpretational processes. This study was conducted to assess their origin and consequently gain an understanding of their contributions to groundwater accumulation and transmission in saprock aquifers. The results, supported by co-located drilling and pumping test data, show that these datasets are indicators of subsurface conditions where high-resistivity unconformal structures directly overlie saturated (low-resistivity) porous media, provided that the resistivity of the first breakout point is less than those from subsequent points. Remote sensing data reveal that these types of curves are common in hard rock and metasedimentary environments. Borehole groundwater yields can also be assessed qualitatively from the number and trend of breakoff points. The integrity of the breakoff points must be affirmed by using more sensitive equipment for data acquisition and repeating the measuring process using different potential electrode separations and—where possible—VES profile orientation