Risk mitigation strategies and policy implications for carbon dioxide (CO2) emission in organically- amended soils in Nigeria

Global food security has been a challenge, especially in Africa. This has attracted the adoption of strategies to improve soil productivity and crop yield. One of such strategies is the use of solid wastes as soil organic matter amendments. An investigation of the effects of soil amendment using poultry manure, sawdust and their mixtures on carbon dioxide (CO2) emission, maize (Zea mays L.) growth and dry matter yield were assessed under laboratory and greenhouse conditions. Top soil obtained from unfertilized plots at the Obafemi Awolowo University Teaching and Research farm, Ile-Ife, Nigeria was used for the experiments. The organic amendments were added at the rate of 10 g/kg, treatments were in triplicates and treatment means were separated using Duncan’s Multiple Range Test at 95% level of significance. Results obtained revealed that CO2 emission decreased while maize heights and dry matter yields significantly (P > 0.05) increased with increasing ratios of poultry manure in the poultry manure-sawdust mixtures. The CO2 emission from poultry manure amended soil was about 61% that from sawdust amended soil while the mean height and dry matter yield in sawdust-amended soils were 84% and 52% respectively those obtained in poultry manure amended soil. This paper concludes that it is essential to design and implement policies that will guide and encourage the use of organic amendments at ratios that can enhance crop yield and mitigate CO2 emission to the environment.Key words: Food security, solid waste, carbon dioxide emission, organic amendments, environment and policy

A New Bioactive Thiophenolic Glycoside From The Leaf Of Massularia Acuminata (G. Don Bullock) Ex Hoyle (Rubiaceae)

Background: Massularia acuminata is a small tree or shrub of tropical rainforest. The leaves are used in Nigerian ethno-medicine for the treatment of microbial infections and pharmacological report suggested the leaf extract as possessing antioxidant activity. This study was therefore carried out to determine the most antioxidant and antimicrobial active  fraction(s) of Massularia acuminata leaf and the constituent(s) responsible for the activities.Matherials and Methods: The leaf of Massularia acuminata was investigated for in vitro antioxidant and antimicrobial activities, using a  2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and agar  dilution method respectively.Results: The ethyl acetate fraction demonstrated the best activities among the partitioned fractions tested. Bioassay guided purification of the most active ethyl acetate fraction led to isolation of a new thiophenolic glycoside, characterized as 4-(3´,3´-dihydroxy-1-mercaptopropyl)phenyl glycosylpyranoside.Conclusion: The isolated compound from the leaf of Massularia acuminata demonstrated antioxidant and antimicrobial activities and may be responsible for the activities of leaf extract and its ethyl acetate fraction, hence this may justify its ethnomedicinal use.Key words: Massularia acuminata, antioxidant, antimicrobial, DPPH, agar dilution, thiophenolic glycosid

Tetrapleura tetraptera: Molluscicidal activity and chemical constituents

No Abstract.Keywords: Molluscicidal; Schistosomiasis; Mimosaceae; Tetrapleura tetraptera; aridan; aridanin The African Journal of Traditional, Complementary and Alternative Medicines Vol. 4 (1) 2007: pp. 23-3

VARIATION STUDIES ON THE VOLATILE OIL OF EUGENIA UNIFLORA

The volatile oil content of the leaves of Eugenia uniflora L. growing in Nigeria was found to be between 0.63-1.09%v/w. From this study, the species is considered an economic source of the oil. The volatile oil content was highest at flowering of the plant and lowest at fruiting. The morphological part of the plant, stage of growth, time and season of collection of the leaves were found to be important factors that determine the amount of the oil produced. Also conditions for storage of the oil and its commercial exploitation were studied. Keywords: Eugenia uniflora, Myrtaceae, volatile oil, variation Nig. J. Nat. Prod. And Med. Vol.1 1997: 28-3

MOLLUSCIDIAL, INSECTICIDAL AND PISCICIDAL ACTIVITIES OF BARRINGTONIA RACEMOSA

The aqueous, methanol, chloroform, ethyl acetate, petroleum ether extracts of Barringtonia racemosa Blume pericarp and seed were evaluated for molluscicidal, larvicial and pisicidal activity against Biomphalaria glabrata, larvae of Aedes aegypti and fish (Clarias lazera and Tilapia nilotica) respectively. The mollusciicidal, larvicidal and piscicidal assays involved incubation of B. glabrata snails, larvae of A. aegypti and fish with extracts of the fruit and seed of B. racemosa compared with niclosamide and T. tetraptera. The pericarp extracts contain more potent molluscicidal components (LC 50 =367.3 — 625.0 ppm) than the seed extracts of the fruit (LC50= 530.53 - 704.27 ppm). The rank order of toxicity for the pericarp extracts tested was for the snails: CHCl3 extract 367.3 ppm >Ethyl acetate extract 390.3 ppm. > methanol extract 530.4 ppm > petroleum ether extract 704.27 ppm. The larvicidal active agents are higher in the seed extracts (LC50 = 588.44 — 1,604.2 ppm) than in the pericarp extracts of the fruit (LC50 = 1,507.0 — 4,000.0 ppm). The rank order of toxicity of the seed extract for the larvae of A. aegypti was: CHCl3 extract 588.44 ppm > MeOH extract 762.5 ppm > petroleum ether extract 1,244.2 ppm > Ethyl acetate extract 1,604.2 ppm. The C. lazera was more resistant to Niclosamide, aqueous extracts of the pericarp and Tetrapleura tetraptera than T. nilotica. These biological activities suggest possible role for B. racemosa in the control of snail intermediate hosts of schistosomiasis and dengue fever. Key Words: Barringtonia racemosa, Leeythidaceae, Aedes aegypti, Dengue, Biomphalaria glabrata, mollusicides, schistosomiasis, piscicides Nig. J. Nat Prod. And Med. Vol.5 2001: 56-5

Antimicrobial And Antioxidant Activities Of Some Nigerian Medicinal Plants

Ten Nigerian plants suggested from their ethnomedical uses to possess antimicrobial and antioxidant activities were studied for their anti-microbial and anti-oxidant properties. Antimicrobial activity was tested against Escherichia coli NCTC 10418, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Candida albicans, Candida pseudotropicalis and Trichophyton rubrum (clinical isolate). Trichilia heudelotti leaf extract showed both antibacterial and antifungal activities and was the most active against all the strains of bacteria tested. Boerhavia diffusa, Markhamia tomentosa and T. heudelotti leaf extracts inhibited the gram negative bacteria E.coli and P. aeruginosa strains whereas those of M. tomentosa, T. heudelotti and Sphenoceutrum jollyamum root inhibited at least one of the fungi tested. At a concentration of 312 μg/ml, hexane and chloroform fractions of T. heudelotti extract inhibited 6 and 14% of the fifty mult-idrug resistant bacteria isolates from clinical infectins, respectively. At ≤ 5mg/ml, the CHCl3 (64%) and aqueous (22%) fractions of T. heudelotti and those of CHCl3 (34%) and EtOAC (48%) of M. tomentosa gave the highest inhibition that was stronger than their corresponding methanol extracts. The corresponding EC50 of the extracts on M. acuminata, T. heudelotti, E. senegalensis and M. tomentosa were 4.00, 6.50, 13.33, and 16.50 ig/ml using the TLC staining and 1,1-dipheyl-2-picry-hydrazyl (DPPH) free radical scavenging assay. Therefore, leaf extracts of M. tomentosa and T. heudelotti, especially the latter, possess strong antimicrobial and antioxidant activities and should be further investigated. These activities justified the ethnomedical uses of these plants. Keywords: keAntimicrobial, antifungal, antioxidant properties, Nigerian medicinal plants. African Journal of Traditional, Complementary and Alternative Medicines Vol. 4 (2) 2007: pp.173-18