Changes in the composition of the pulp, alpha-amylase activity and titratable acidity during the controlled rotting of egusi fruits (Colocynthis citrullus l.) for the harvesting of the seeds

The laboratory rotting of Egusi Fruits was completed in 120 hours. At this stage pulp became soft and the seeds were extracted easily with the fingers. The changes in the composition of the pulp, alpha-amylase activity and titratable acidity during the controlled rotting of egusi fruit (Colocynthis citrullus L.) for the harvesting of the seeds showed that moisture content (MC) increased from 82.04% at 0 hour of rotting to 85.00% at 120 hours of rotting. The Titratable acidity increased from 0.10mg lactic acid/g, wet matter (WM) at 0 hour to 0.70mg lactic acid/g, at 120 hours. The total carbohydrate (water soluble carbohydrate) decreased from 10.76% at 0 hour to 0.35% at 120 hour and the reducing sugars also decreased from 1.25mg/g (WM) at 0 hour to 0.25mg/g (WM) at 120 hours; the protein content increased from 0.39% at 0 hour to 4.38% at 96 hours and then fell to 1.14% at 120 hours. The alpha-amylase activity which was not detectable at 0 hour reached a peak of 0.80mg/g (WM) at 48 hours and then fell to 0.02mg/g at 120 hours. The crude fat decreased from 6.85% at 0 hour to 6.72% at 120 hours. The pH rose from 5.20 at 0 hour to 6.70 at 120 hours while the temperature rose from 28.00C at 0 hour to 300C at 120 hours. These changes resulted in the softening of the pulp and hence facilitating the easy removal of the seeds from the fruits with fingers.KEYWORDS: Rotting, Egusi, Pulp, Composition, Alpha-amylase, titratable acidity

Application of Used Engine Oil in Soil-Cement Stabilization

A lot of studies has shown that the addition of oils to some soils at 3% and 6% contaminations by dry weight resulted in an increase in the unsoaked California bearing ratio (CBR) of the soil. This paper presents the result of investigating the applicability of used engine oil at 3% contamination as a means of reuse in the production of ordinary Portland cement (OPC) stabilized soils. The soils which are classified as clayey Gravel (GC) and clayey Sand (SC) according to the unified soil classification system were subjected to classification tests, compaction tests, soaked and unsoaked CBR tests, X-ray fluorescence and X-ray diffraction tests. The results show that there is a general reduction in the optimum moisture content of the oil contaminated soils while the effect of oil contamination on maximum dry density varied for the two types of soils under consideration. Furthermore, an increase of 130.45% and 240.37% were observed respectively in the CBR values of the oil contaminated soils after curing it for six days and soaking for 24hours in water at 8% OPC content.  The procedure for curing, soaking and CBR testing were all in line with the recommendation of the Nigerian general specification for roads and bridges.http://dx.doi.org/10.4314/njt.v34i1.1

Studies on lysine production by Bacillus megaterium

A Lysine-producing strain recovered from soil was found to produce large amount of the amino acid. The bacterium identified as Bacillus megaterium SP 14 accumulated a lysine yield of 3.56 mg/ml in a broth culture in 96 h. Fermentation experiments show that 8.0% (w/v) glucose and 4.0% (w/v) ammonium chloride used as sources of carbon and nitrogen, respectively, in a medium/fermenter volume ratio of 25.0%, influenced accumulation of the amino acid. Amino acids other than the aspartate family at 0.01% (w/v) stimulated growth and improved lysine yield. Addition of 0.01 unit/ml penicillin to the fermentation medium, immediately after inoculation, stimulated growth and appreciably enhanced lysine accumulation.African Journal of Biotechnology Vol. 4 (7), pp. 633-638, 200

Stability and durability of sawdust ash-lime stabilised black cotton soil

The assessment of the durability of twelve cylindrical samples of black cotton soil, a well-known problem soil, stabilized with a combination of 4%lime and 16% sawdust ash were carried out in laboratory using the methods of [1] and that recommended by [2] and [3]. The results showed that the unconfined compressive strength of the samples under varying curing and soaking conditions ranged from 1217kPa to 265kPa while the durability indices were 59.51% and 59% respectively. Thus, the stabilizers have elevated the otherwise non-durable soil into the marginally durable zone.Keywords: Black cotton soil, Durability, Sawdust ash, Stabilisation, Unconfined compressive strengt

Evolution of Volatile Flavour Compounds during Fermentation of African Oil Bean ( Pentaclethra macrophylla

Fermented African oil bean (Pentaclethra macrophylla Benth) seed is a successful and well studied seasoning and snack in parts of Western Africa. GC-MS analysis of fermenting seeds revealed a mixture of several volatile aroma compounds which changed with time and starter organism. During natural mixed culture process 36 volatile compounds including 12 hydrocarbons, 10 esters, 5 alcohols, 2 phenols, 2 ketones, and one each of furan, amine, acid, thiophene, and lactone were identified. When Bacillus subtilis was used in pure culture, 30 compounds comprising 10 hydrocarbons, 8 esters, 3 alcohols, 2 amines, 2 sulfur compounds, and one of each of acid, aldehyde, phenol, ketone, and furan were identified. Sample fermented with B. megaterium produced 29 aroma compounds comprising 9 hydrocarbons, 10 esters, 2 nitrogenous compounds, 2 ketones, 3 alcohols, and one of each of lactone, aldehyde, furan, and amine. Methyl esters of various long chain fatty acids may be key aroma compounds, based on consistency and persistence. Qualitative or quantitative contribution of individual compounds may only be determined following flavour threshold analysis

Studies Of Heat Resistant Fungi In The Soil:Talaromyces flavus Isolated In Nigerian Soils

Abstract Heat resistant fungi are a group of fungi which are able to withstand thermal processes employed in the preservation of most acid foods. A total of 85 soil samples collected from gardens/farmlands in Ohodo, EnuguEzike, Ogbede, Adani, Oturkpo, Umuahia/Orlu, Imilike, and Gboko were examined for the presence of heat resistant fungi using standard methods.HRF were isolated from 74 soils representing approximately 94%. Fungal counts ranged from non-detectable to 437 colony forming units per 2g of soil. Neosartorya fischeri was the most common isolate. Other isolates were Talaromyces flavus, Eupenicillium cinnamopurpurem, Eupenicillium crustaceum,Emeriella rugulosa and Paecilomyces variotii/Byssochlamys fulva

Moisture Sorption Behaviour and Mould Ecology of Trade Garri Sold in South Eastern Nigeria

Garri is a creamy white or yellow starchy grit produced by roasting to gelatinization and dryness of peeled, washed, mashed, and fermented dewatered cassava roots. It is the most important product of cassava in West and Central Africa. Mean moisture content of yellow and white garri was 11.11% and 10.81% within 24 hrs of sampling from the market, increasing to 17.27% and 16.14%, respectively, following 3 months of storage at room temperature. The water activity of samples varied from initial 0.587 to 0.934 following storage. Moisture sorption isotherms, determined by static gravimetric techniques at 20° and 30°C, showed temperature dependent BET Sigmoidal type II behaviour typical of carbohydrate rich foods but modulated very slightly by the content of palm oil. Equilibrium moisture content decreased with increase in temperature at constant water activity. A total of 10 fungal species belonging to the genera Mucor, Penicillium, Cephalosporium, Aspergillus, Scopulariopsis, Rhizopus, and Paecilomyces were identified, with range increasing with water activity of samples