Evaluation of antioxidant activity of Tetracarpidium conophorum (Müll. Arg) Hutch & Dalziel leaves.

This study evaluated the antioxidant activity as well as bioflavonoid content of the methanol and ethanol-water extracts of the fresh and dried leaves of Tetracarpidium conophorum. Antioxidant activity was determined by spectrophotometric methods using DPPH free radical, nitric oxide radical inhibition and ferric reducing antioxidant power assays. In addition, total phenolics, flavonoids and proanthocyanidin content were also determined. The ethanol: water extract of the dried leaves had the highest antioxidant activity with a 50% inhibition of DPPH at a concentration of 0.017 mg/mL compared to the standards, Vitamin C and Vitamin E with inhibition of 0.019 and 0.011 mg/mL, respectively. This extract also showed nitric oxide radical inhibition activity comparable to that of rutin, 54.45% and 55.03% for extract and rutin, respectively, at 0.1 mg/mL. Ferric reducing power was also comparable to that of ascorbic acid (281 and 287 µM Fe (11)/g, resp.) at a concentration of 1 mg/mL. The methanol extract of both the dried and the fresh leaves had higher phenolic, flavonoids and proanthocyanidin content than the ethanol:water extract. The study reveals that T. conophorum can be an interesting source of antioxidants with their potential use in different fields namely food, cosmetics and pharmaceuticals.

The physicochemical and antibacterial properties of ciprofloxacin-Mg2+ complex.

PURPOSE: Co-administration of quinolone antibiotics with cation-containing medicaments such as, antacids has been reported to influence the overall bioavailability leading to subtherapeutic plasma concentrations of these antibiotics in humans. OBJECTIVES OF THE STUDY: The present work was designed to evaluate the binding constant, binding molar ratio, influence of temperature on the binding constant of ciprofloxacin-Mg2+ and to determine the antimicrobial activity of ciprofloxacin and ciprofloxacin-Mg2+. METHODS: Job's method of continuous variation and Bonesi-Hildebrand equation were adopted to determine the molar ratio and stability constant respectively. The antibacterial activity was determined by the Agar diffusion method. RESULTS: A complexation molar ratio of 1:1 was obtained for ciprofloxacin-Mg2+ complex. The stability constants were 3.59 and 3.50 at 25 degrees C and 60 degrees C respectively. There was a significant difference between the zones of inhibition of ciprofloxacin-Mg2+ complex and that of ciprofloxacin alone against E. coli, P. aeruginosa, and S. aureus (p < 0.05). This difference showed that the complex formed was not as active as ciprofloxacin. CONCLUSION: The present studies have shown that ciprofloxacin readily complex with Mg2+ and that the stability constant was temperature dependent. The antibacterial activity of ciprofloxacin was markedly reduced in the presence of Mg2+. Concomitant administration of ciprofloxacin with Mg2. containing medicaments should be avoided to prevent resistance.

Invitro evaluation of the neutralising capacity of twenty brands of antacids in Lagos, Nigeria.

BACKGROUND: The use of substandard drugs is a great threat to the lives of people in the community. Identification of substandard drugs is important to exclude their use in clinical practice. These drugs may lead to reduced efficacy of pharmacotherapy. Antacid preparations are weakly basic and consist of metal salts, most commonly aluminium hydroxide or magnesium hydroxide. These salts dissociate to neutralise gastric acid and form neutral salts. The ultimate goal of antacid therapy is to reduce the concentration and the total load of acid in gastric juice with a pH of 1.3 to a pH between 3.5 and 5.0. OBJECTIVE: The aim of this work is to carry out an in-vitro test on the acid neutralising capacity (ANC) of commonly available antacid brands in Lagos market. METHOD: The British pharmacopoeia (BP) method of analysis of antacids was adopted. Twenty different brands of antacid suspensions and tablets were analysed. RESULT: Brand SH suspension gave the highest neutralising capacity, 101.65 ml +/- 0.15, while brand SN gave the lowest, 99.75 ml +/- 0.75. All the fourteen antacid suspensions analysed complied with the official specification and therefore passed the analysis. Brand TB tablet gave the highest acid neutralising capacity (ANC), 54.10 ml +/- 0.2 while brand TD 49.50 ml +/- 0.1 gave the lowest. All the six antacid tablet brands analysed passed the assay. The ANC of an antacid is a parameter used to measure the effectiveness of an antacid in relieving ulcer pain. CONCLUSION: The acid-neutralising capacity of the antacid brands analysed were within the BP specification. The acid neutralising capacity of antacids should be determined before administration.

Phytochemical Screening and Free Radical Scavenging Activities of the Fruits and Leaves of Allanblackia floribunda Oliv (Guttiferae)

Purpose: To compare the phytochemical constituents in the leaves and fruits of Allanblackia floribunda and determine their free radical scavenging activity. Methods: The fruit and leaves of AF collected from the uncultivated farmlands of Okeigbo; Ondo State; Nigeria; were dried; milled and extracted with methanol. Phytochemical screening was carried out according to standard procedures. Free radical scavenging activity was determined by measuring the decrease in the visible absorbance of 2;2-diphenyl-1-picrylhydrazyl (DPPH) on addition of the plant extract. The mean inhibitory concentration (IC50); which is the concentration of extract needed to decrease the initial absorbance of DPPH by 50was determined graphically. Total phenolic; flavonoids and proanthocyanidin contents were determined by spectro-photometric methods. Results: Alkaloids; anthraquinones; tannins; saponins; steroids; terpenoids; flavonoids and cardiac glycosides were found to be present in both the fruits and leaves. Only AF fruit contained phlobatannins. IC50 values of 0.01; 0.02 and 0.1 mg/ml were recorded for Vitamin E; AF leaves and AF fruits respectively. Total phenolic; total flavonoid and proanthocyanidin contents were 65; 0.07 and 2.38 mg/g of powdered plant material for AF fruits; and 12; 51.35; 19.5 mg/g of powdered plant material for AF leaves as gallic acid; rutin and catechin equivalents respectively. Conclusion: AF leaves are five times more potent as a free radical scavenger compared to the fruits though the fruit was found to contain a higher phenolic content

Phytochemical Screening and Free Radical Scavenging Activities of the Fruits and Leaves of Allanblackia floribunda Oliv (Guttiferae)

Purpose: To compare the phytochemical constituents in the leaves and fruits of Allanblackia floribunda and determine their free radical scavenging activity. Methods: The fruit and leaves of AF collected from the uncultivated farmlands of Okeigbo; Ondo State; Nigeria; were dried; milled and extracted with methanol. Phytochemical screening was carried out according to standard procedures. Free radical scavenging activity was determined by measuring the decrease in the visible absorbance of 2;2-diphenyl-1 -picrylhydrazyl (DPPH) on addition of the plant extract. The mean inhibitory concentration (IC50); which is the concentration of extract needed to decrease the initial absorbance of DPPH by 50was determined graphically. Total phenolic; flavonoids and proanthocyanidin contents were determined by spectro-photometric methods. Results: Alkaloids; anthraquinones; tannins; saponins; steroids; terpenoids; flavonoids and cardiac glycosides were found to be present in both the fruits and leaves. Only AF fruit contained phlobatannins. IC50 values of 0.01; 0.02 and 0.1 mg/ml were recorded for Vitamin E; AF leaves and AF fruits respectively. Total phenolic; total flavonoid and proanthocyanidin contents were 65; 0.07 and 2.38 mg/g of powdered plant material for AF fruits; and 12; 51.35; 19.5 mg/g of powdered plant material for AF leaves as gallic acid; rutin and catechin equivalents respectively. Conclusion: AF leaves are five times more potent as a free radical scavenger compared to the fruits though the fruit was found to contain a higher phenolic content

Phytochemical Screening and Antioxidant Activities of some Selected Medicinal Plants Used for Malaria Therapy in Southwestern Nigeria

Purpose: Oxidative stress has been shown to play an important role in the development of anaemia in malaria. Indeed; increase in total antioxidant status has been shown to be important in recovery from malaria. The antioxidant activities of four medicinal plants traditionally used in the treatment of malaria in southwestern Nigeria were determi- ned. Methods: The ethanolic extracts of the leaves of Carica papaya Linn. [Caricaceae] ; stem bark of Magnifera indica Linn. [Anacardiaceae]; leaves of Psidium guajava Linn. [Myrtaceae] and the leaves of Vernonia amygdalina Del. [Compositae]; were used in the present study. The plant parts commonly used in the locality in malaria therapy were employed in this study. The plants were screened for the presence of phytochemicals and; their effect on 2;2-Diphenyl-1-picryl-hydrazyl radical (DPPH) was used to determine their free radical scavenging activity. Results: Phytochemical screening of the plants showed the presence of flavonoids; terpenoids; saponins; tannins and reducing sugars. M. indica did not contain cardiac glycosides and alkaloids while; P. guajava also showed the absence of alkaloids and anthraquinones. Anthraquinones was similarly absent from V. amygdalina. Concentrations of the plant extracts required for 50inhibition of DPPH radical scavenging effect (IC50) were recorded as 0.04 mg/ml; 0.313 mg/ml; 0.58 mg/ml; 2.30 mg/ml and 0.054 mg/ml for P. guajava; M. Indica; C. papaya; V. amygdalina and Vitamin C; respectively. Conclusion : All the plants showed potent inhibition of DPPH radical scavenging activity; P. guajava being the most potent. The free radical scavenging (antioxidant) activities of these plants probably contribute to the effectiveness of the above plants in malaria therapy