A Multivariate Analysis of Factors Influencing Green Space Provision in Residential Neighbourhood of Sub-Saharan African Cities

This research examines factors that influence the level of conformity to green space provision. Primary data was collected for three (3) types of residential neighbourhoods: Federal, State and Private. Reconnaissance survey revealed there are 8, 19 and 12 residential neighbourhoods respectively for Federal, State and Private. Ten (10%) of each were selected and thus, 1, 2, and 1 was selected for the Federal, State and Privately owned residential neighbourhoods. The total number of questionnaire that was administered on the household heads in the four (4) selected residential neighbourhoods was three hundred and thirty-two (332) but only three hundred and seven (307) was retrieved. Explanatory factor analysis was conducted on the perceived variables that could affect provision of green space. Within the first component there exist similarities between all the three (3) variables that were highly loaded {residential density (0.832), nature of surrounding neighbourhood (0.825) and inadequate land (0.745)}. Each of them were related to the environment and thus the first factor affecting the provision of green space within residential neighbourhood could be regarded as physical and natural factors. On the other hand, the column for the second component had three (3) variables that were related to activities within the planning authorities (agency in charge of green space provision and compliance). These were, lack of working tools in planning authorities (0.856), lack of qualified staff in planning authorities (0.821) as well as inadequate number of staff in planning authorities (0.757). The third column represents factors relating to the government and it governmental, while the fourth and final component (factor) could be termed political factors. A near perfect structure of the variables emerged from the factor analysis and thus the reduction of the thirteen variables to four major factors. The study concluded that, better provision and care for green spaces within residential neighbourhood will require an effective policy framework, in which all decision-makers, can operate and work in collaboration. Key Words: Cities, Green-space, Residential Neighbourhood and Sub-Saharan

Antitrichomonal and antioxidant activities of Dorstenia barteri and Dorstenia convexa

Dorstenia barteri and D. convexa extracts and some isolated components of the former were investigated for effectiveness against Trichomonas gallinarum and compared with quercetin and quercitrin. The antioxidant activity of the extracts/compounds was also determined. The minimum lethal concentrations (MLCs) for the extract of D. barteri leaves and twigs at 24 h were found to be 15.625 and 15.625 µg/ml, respectively. However, the MLCs of the leaf and twig extract of D. convexa were 125 and 437.5 µg/ml, respectively. The prenylated and geranylated chalcones were as active as the prenylated flavones, 6-prenylapigenin and the diprenylated derivative 6,8-diprenyleridictyol. The order of the antitrichomonal activity of the compounds at 24 h was: quercetin (0.121 µg/ml) > quercitrin (0.244 µg/ml) > or = bartericin B (0.244 µg/ml) > bartericin A (0.73 µg/ml) > stigmasterol (0.98 µg/ml) > 6,8-diprenyleridictyol = isobavachalcone = dorsmanin F (31.25 µg/ml). D. barteri extracts, quercitrin, and bartericin A, and the prenylated flavonoids had potent antioxidant properties. The twig extract of D. barteri was more potent than the leaf extract. Moderate (EC50 >50 µg/ml) and high (EC50 <50 µg/ml) antioxidant activities were detected in the leaf and twig extracts of D. barteri and the prenylated flavonoids. Prenylated flavonoids and the isolated compounds with antioxidant properties described here may account for the anti-inflammatory action of these extracts. The antitrichomonal and antioxidant activities shown by the extracts and compounds in this study are consistent with the ethnomedicinal and local use of the Dorstenia species studied