Bio-preservation Potential of Leaf Extracts of Ocimum gratissimum L. on Fresh-Cut Fruits of Citrullus lanatus (Thunb)

This study was conducted to assess the retail market edibility quality of Citrullus lanatus fresh-cut fruits enhanced with the extracts from the leaves of Ocimum gratissimum. Analytical graded ethanol and hexane were used to extract O. gratissimum leaves differently. The fresh-cut fruits were dipped in the extract obtained from the leaves and reconstituted with Tween 80, fruits treated with Tween 80 and untreated fruits were used as controls. The treated fruits with the extracts, fruits treated with Tween 80 and fruits without treatment were analysed for quality test using the following parametres: carotenoids, ascorbic acids, total phenolic acid, pH, total soluble solids, microbial loads and moisture contents at day 0 and at an interval of 3, 5 and 9 days. The quantitative estimations of the phytochemicals in the extracts were determined and the constituents in the essential oil of the hexane extracts were established with the use of GC-MS system, and the data generated from the study were analysed with SPSS 20.0. This study showed that there was lower reduction in moisture content, pH, ascorbic acid and potential browning values of the treated fresh-cut fruits of C. lanatus, compared to higher reduction in untreated and tween 80 treated fresh-cut fruits during the storage intervals for nine days. The treated fresh-cut fruits had higher Brix values of TSS, total phenolic acid and carotenoids contents, compared with the untreated fresh-cut fruit, which was low during the period of storage for nine days. The microbial loads in the untreated fresh-cut fruit of C. lanatus were higher than what was obtained in the treated fresh-cut fruits of C. lanatus after nine days of storage. The yield of Alkaloids from ethanol and hexane extracts were 54.25±0.09 mg/100g and 51.86±0.06mg/100g respectively. γ-Terpinene (17.21 %) and (E)-9-Octadecenoic acid (11.848 %) had the highest percentage composition of phytoconstituents present in the essential oil from Citrullus lanatus. This study was able to establish the preservation potential of Ocimum gratissiumum on fresh-cut fruits of Citrullus lanatus.Keywords: Citrullus lanatus; Food Safety; Ocimum gratissiumum; Quality parametre

Growth of Gliricidia and Leucaena as affected by Rhizobium inoculation and N and P fertilizar application in Nigeria

Six field trials to determine the effects of rhizobium inoculation, and N and P fertilizer applications on the early growth of Gliricidia sepium and Leucaena leucocephala were conducted in farmers' fields at three sites: Alabata and Ajaawa located in the derived savanna of southwestern Nigeria and Zakibiam located in the southern Guinea zone of ease central Nigeria. At Alabara and Ajaawa the soils are Entisols and mean annual rainfall was 1300 mm; at Zakibiam, the soils belonged to the Alfisol group with a mean annual rainfall of 1070 mm. By 15 MAP Gliricidia responded significantly to inoculation in four fields and to fertilization in two fields. Leucaena responded significantly to inoculation in three fields and to fertilizer application in one field. The performance of the two species was better at Alabata and Ajaawa than at Zakibiam. The better performance may be related to soil fertility and rainfall. Gliricidia showed better early growth than Leucaena. The faster growing Gliricidia responded better to inoculation and fertilization. The mean response to rhizobium inoculation was higher in the control than in plots fertilized with N. The N response was more pronounced than P response in spite of the low available P level of the fields. Inoculation, and N and P fertilization increased the N and P uptake of the two species. To ensure the early establishment of both species, inoculation with rhizobium and starter applications of N and P fertilizers is highly recommended