Ethical Issues and Standards of Responsible Research Conduct and Monitoring in an Adventist Institution of Higher Learning - The Babcock Experience

Ethical issues and standards of responsible research conduct involving human participants are important considerations in any institution of higher learning and in particular Adventist institutions. Research conduct and ethics are reviewed and approved before they begin by the Babcock University Health Research Ethics Committee (BUHREC

Phytochemical constituents and antioxidant activities of aqueous and methanol stem extracts of Costus afer Ker Gawl. (Costaceae)

Medicinal plants contain bioactive compounds capable of preventing and fighting oxidative related diseases. These compounds must be screened and assayed before effective drugs are developed. Thus, phytochemical constituents and antioxidant activities of aqueous and methanol stem extracts of Costus afer Ker-Gawl were evaluated. C. afer contained flavonoids, phenols, anthraquinones, cardiac glycosides, terpenoids, alkaloids and tannins. Preliminary screening of free radical scavenging activity of extracts with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) using thin layer chromatography tested positive. The aqueous extract had a higher free radical scavenging activity with IC50 (concentration of samples required for 50% inhibition of DPPH radical activity) value of 64.42 g/ml than methanol extract (92.33 g/ml). Furthermore, total phenolic content in aqueous extract (0.66 ± 0.02 mg gallic acid equivalent/g) was significantly higher (p < 0.05) than methanol extract (0.52 ± 0.01 mg gallic acid equivalent/g). In addition, inhibition of lipid peroxidation by aqueous extract (80.60 ± 0.28%) was significantly higher (p < 0.05) than methanol extract (77.00 ± 0.84%). Nevertheless, methanol and aqueous extracts of C. afer possess anti-oxidative properties as well as bioactive metabolites. Thus, stem extracts of C. afer could serve as sources of antioxidants and bioactive compounds for nutrition and therapeutic purposes.Key words: Costus afer, phytochemicals, antioxidant, phenol, nutrition, therapeutic

Cytomorphological analysis of a novel hybrid from Solanum melongena 'Golden' x S. scabrum 'Scabrum' (Solanaceae)

Genotype manipulation through the introduction of novel genes for improved yield, agronomic qualities and a larger gene pool informed an experimental cross between diploid Solanum melongena 'Golden' (2n = 2x = 24) and tetraploid S. scabrum 'Scabrum' (2n = 4x = 48). The F1 fruit contained eight seeds which had a 100% germination and a chromosome number 2n = 6x = 72. Surviving hybrids were closer to the diploid parent in many characters. Leaves were fairly lobed, sparsely hairy and were 13.5 x 8.6 cm in the hybrid compared to the hairy, deeply lobed, 14.8 x 10.6 cm leaves in the diploid and glabrous, entire and 11.4 x 10.6 cm leaves in the tetraploid parent. The inflorescence in the hybrid was a raceme as in the diploid parent but was umbellate in the tetraploid. Pollen viability was 38.2% in the hybrid but was 71% and 97.4% in the diploid and tetraploid parents, respectively. Fruit was seedless in the F2; it was round and red, containing 384 seeds, globose-shaped, yellow seeds in the diploid, and 67, round, purple seeds in the tetraploid parent. Meiosis was regular in the hybrid with few univalents and impaired bivalents due to dissimilar parental genomes. Mitotic chromosomes were asymmetrical with various sizes. Epistasis and negative gene interaction mechanisms were implicated in the hybrids� low quality and breakdown. Backcross to the tetraploid parent may bring about gene recombination and allelic realignment for desirable phenotypes in the F2 and subsequent generations. Endoduplication of the triploid zygote might have produced an autoallohexaploid hybridLa manipulación genotípica permite la introducción de genes nuevos para la mejora de la producción y otras cualidades agronómicas. Se llevó a cabo un cruce experimental entre Solanum melongena 'Golden' (diploide, 2n = 2x = 24) y S. scabrum 'Scabrum' (tetraploide, 2n = 4x = 48). Los frutos de la F1 contenían ocho semillas con un 100% de germinación y un nº de cromosomas 2n = 6x = 72. Los híbridos que sobrevivieron estaban más próximos, en muchos caracteres, al parental diploide. Las hojas del híbrido eran de 13,5 x 8,6 cm, algo lobuladas y tenían escasos pelos, mientras que las del diploide eran de 14,8 x 10,6 cm, con pelos y profundamente lobuladas, y las del parental tetraploide de 11,4 x 10,6 cm, sin pelos y sin lobular. Las inflorescencias del híbrido y del diploide eran en racimo, mientras que en el tetraploide eran umbeladas. La viabilidad del polen fue del 38,2%, 71% y 97,4% en el híbrido, diploide y tetraploide, respectivamente. El fruto de la F2 no tenía semilla, era redondeado y rojizo; mientras que en el parental diploide contenía 384 semillas, era alargado y amarillo, y en el tetraploide tenía 67 semillas, y era redondeado y púrpura. La meiosis en el híbrido fue regular, con algunos cromosomas sin aparear. Los cromosomas mitóticos fueron asimétricos y de varios tamaños. La baja calidad y fallo de los híbridos se explican por la epistasis y los mecanismos de interacción génica negativos. El retrocruzamiento con el parental tetraploide puede dar una recombinación génica y realineamiento de los alelos para los fenotipos deseables en la F2 y generaciones siguientes. La endoduplicación del cigoto del tetraploide podría haber producido un híbrido autoalohexaploid

Effect of X-ray irradiation on growth physiology of Arachis Hypogaea (Var. Kampala)

Small doses of X-ray may stimulate cellular activities and growth while higher doses may cause higher aberrations. Seeds of Arachis hypogaea cv Kampala were exposed singly to X-ray radiations (6 mA-77 mA) X-ray significantly decreased seed germination above 6 mA, reduced root and shoot growth as X-ray exposure increased. X-ray radiation causes chromosomal aberration. Therefore, higher X-ray radiation affects the plant germination negatively by retarding the growth