Showing papers in "Electronic journal of environmental, agricultural and food chemistry in 2009"

Characterization of seed and seed oil of Hura crepitans and the kinetics of degradation of the oil during heating.

Abstract: The seed and seed oil of Hura crepitans were analyzed for proximate composition and physico-chemical characteristics. The seed is a good source of oil and protein; these were found to be 37.78% and 22.20% respectively. The saponification and iodine values suggest the use of this oil in liquid soap, shampoo and oil based ice cream production. The moisture content is also low (3.00%) which indicates the possibility of long shelve-life. The degradation kinetic of the oil was also investigated. The thermal oxidation of the double bonds of the oil showed a first-order thermal oxidation kinetic and the Arrhenius plot yielded a straight line with a slope equivalent to activation energy of 1.989KJ\mol.There is the possibility of considering the seed as feed supplement and its oil for industrial application.

Evaluation of the pasting and some functional properties of starch isolated from some improved cassava varieties in Nigeria.

Abstract: Improved cassava of 13 cultivars (NR01/004, NR01/0161, NR01/0071, CR14A-1, CR.41 – 10, AR38 – 3, TMS01/0040, TMS01/1086, TMS00/0210, TMS00/0203, TMS00/0214, TMS30572CK and Local best (CK) were converted into starch and analysed for some functional and pasting properties. Variations were observed in the functional properties of the starch samples; water absorption capacity ranged from 59.75 – 68.02%; oil absorption capacity 60.70 – 80.01%; swelling power 5.49 – 6.92% and solubility index 4.25 – 5.96%. Significant differences (P lowest. The setback viscosity ranged between 9.75 – 49.25 RVU with starch from local best CK having the highest and that from TMS01/0040 having the lowest. The pasting temperature ranged from 63.00 – 64.70°C, with starch from TMS00/0214 having the highest and that from NR01/0161 having the lowest. There were significant differences (P best CK had the highest and that from TMS00/0203 had the lowest. Significant differences were observed in the amylose and starch contents of the cassava cultivars.

Impact of tannery and textile effluent on the chemical characteristics of Challawa River, Kano State, Nigeria.

Abstract: The impact of effluent from tanneries and textile on the chemical characteristics of Challawa River was carried out for a periods of one year. Water samples were collected on quarterly basis beginning from the months of June to September, 2007 (Rainy season), November, 2007 - February, 2008 (Harmattan period) and March - May, 2008 (Dry season) to reflect the seasonal 18 factors. Water samples from these areas were collected and designated S to S for the determinations of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), Dissolved oxygen (DO) total dissolved solid (TDS), anions and trace element. These parameters were determined using standard procedures. The concentrations of BOD (40.20±42.65 to 33.91 ±678.36mg/l.), COD (158.00 ±3439.11 to 15.41 ±210.33mg/l), %TOC (0.21 to 5.54 %) were higher than the WHO limits for the protection of fish and other aquatic life. The concentrations of heavy metals in the water and sediment samples were higher than the WHO guideline values for the protection of aquatic life. This is expected owing to its location close to tanneries and textile industries. Results of Analysis of variance (ANOVA) results revealed that BOD, COD, DO, TOC, TDS, nitrate, nitrite, sulphate, phosphate, heavy metals and chloride were significantly different among 13 the sampling points and seasons with exception of point S -S where the was no marked seasonal 5 variations. Point S which is the control point (upstream) recorded the lowest concentrations for all the parameters studied. The relationship between %TOC with BOD and COD; TDS with BOD and COD were also observed. The Pearson linear correlation analysis showed that the mean concentrations of heavy metals in the water and sediment samples revealed significantly positive correlated values. Base on the above results, the study underscores the need for immediate remediation programs to control the discharged of tanneries and textile effluent into Challawa River.

Antifungal activity screening and HPLC analysis of crude extract from Tectona grandis, Shilajit, Valeriana wallachi.

Abstract: The antifungal activity of methanolic crude extract of Tectona grandis, Shilajit, Valeriana wallachi was investigated against Alternaria cajani, Curvularia lunata, Fusarium sp., Bipolaris sp. and Helminthosporium sp. at different concentrations (1000, 2000, 3000, 4000 and 5000 �og/ml). Better antifungal activity was observed with the extracts of Valeriana wallachi, that showed excellent inhibitory activity against Helminthosporium sp. (96.15%) followed by Shilajit extract against Alternaria cajani (95.12 %) and Helminthosporium sp. (95.00 %) at concentration of 5000 �og/ml. Among different fungi tested Bipolaris sp. and Fusarium were found to be more sensitive to crude extract when compared to others. The increase in the production of phenolics in the extract can be correlated with the induction of resistance in treated plants against phytopathogenic fungi. HPLC analysis of the crude extract of medicinal plants showed four different Phenolic acids (Tannic acid, Gallic acid, Ferulic acid and Caffeic acid). The results of the study provide scientific basis for the use of the plant extract in the future development as antioxidant, antibacterial, antifungal and anti-inflammatory agent.

Antimicrobial activity of aqueous and ethanol extracts of nine Nigerian spices against four food borne bacteria.

Abstract: The antimicrobial activity of the aqueous and ethanol extracts of nine Nigerian spices (Xylopia aethiopica, Myristia fragran, Aframomum sceptum, Garcina cola, Zingiber official, Piper guanine, Allium cepa, Vanilla fragran and Opium gratissimum) against Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris and Streptococcus faecalis was evaluated by determining the minimum inhibitory concentrations (MIC) of the extracts By and large, all the extracts possessed antimicrobial properties with the MIC of the extracts in the range of 5 mg/ml to 22 mg/ml The ethanol extract of V fragran (MIC=5 mg/ml ─ 10 mg/ml) was the most potent of all extracts while the least potent of the extract was M fragran (MIC=18 mg/ml ─ 22 mg/ml) Key word: Antimicrobial, extracts, aqueous, ethanol, spices, bacteria, minimum inhibitory concentrations

Characterization of nutraceutical compounds in blue green alga Spirulina maxima.

Abstract: This work was conducted to evaluate the influence of culture conditions (nitrogen concentrations in growth medium) on characterization of some nutraceutical compounds in algal Spirulina maxima. Antioxidant and antibacterial activities as well as chemical composition of organic extracts obtained from different cultures were examined. The amounts of total carotenoids, chlorophylls-derived and phenolic compounds were associated inversely with concentration of nitrogen in growth media. The antibacterial results showed that all S.maxima extracts exhibited great potential antibacterial activities against six bacterial strains with inhibition zones ranged 7 - 18 mm and MICs values ranged 30 - 40 µg/mL. Also, all S.maxima extracts possessed potent antioxidant properties as comparable to commercial antioxidants. The chromatographic analyses of Spirulina organic extracts with TLC and HPLC showed that carotenoids, chlorophyll-derived and phenol compounds were presence as main constituents and their quantities was significantly changed dependant on culture conditions. Thus, it could be suggested that the Spirulina is useful bio-system for production bioactive compounds possess an antioxidants and antimicrobial principles and as natural pigments.

Associative impact of bio- and organic fertilizers on geranium plants grown under saline conditions

Abstract: Salinization plays a major role in soil degradation. Every year more and more land becomes non productive owing to salt accumulation. So it seems valuable, to test medicinal plant for their salt tolerance capacity. In the present investigation, experiments were conducted to study the effect of saline water in addition to bio and organic fertilization treatment on geranium plant growth, mineral and chemical constituents. Salinity affected most of the morphological parameters and decreased the growth performance. The use of peanut compost slightly increased plant fresh and dry weights. Although the use of compost full dose at 3000 ppm salinity level led to an increase in plant height and number of branches in the second cut. For the chemical constituents, the biofertilizer and compost application under saline conditions did not show any positive change in N, P, K contents except for Na% where it reached 1.919 when using (half dose of compost + Bio) at 3000 ppm and reached 1.97 when using (full dose of peanut compost + Bio) at 6000 ppm compared to their control. The oil percentage decreased at high salinity level of 6000 ppm but at 3000 ppm the oil percentage reached 0.4 when treated with (HD+Bio) and 0.6% when plants were supplied with full dose of peanut compost compared to the control. The major essential oil constituents were Geraniol and Citronellol. The highest level of oxidized compounds was attained by the untreated plants (control) and the plants supplied with half dose of compost.

Response of Seed Yield, Yield Components and Oil Content to the Sesame Cultivar and Nitrogen Fertilizer Rate Diversity

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Maize-cowpea intercropping and weed suppression in leaf stripped and detasselled maize in Zimbabwe.

Abstract: A study was conducted to evaluate the suitability of cowpea (Vigna anguiculata) varieties for maize-cowpea intercropping in leaf stripped and detasselled maize at the University of Zimbabwe Farm during the 2005/6 cropping season. A Randomized Complete Block Design (RCBD 4*3*2 factorial experimental design was adopted. Three factors that included cowpea variety, cropping system and detasselling/leaf stripping were used for the design. Trailing and climbing varieties invested more dry matter to vegetative growth than the new upright bushy cultivars that invested most of their dry matter in grain yield. Leafstripping and detasselling significantly increased cowpea grain and maize yields. Sole cowpea grain yield was significantly higher than grain yield from their respective intercrops. Weed density significantly (P<0.01) decreased at 6 weeks after crop emergence (WACE and at maize physiological maturity (PM), and biomass decreased at 6 (WACE) and maize (PM) respectively. Weed density was reduced in the intercrops when maize was intercropped with CBC3, BEB and L. Landrace. In contrast R.ex-Mbare was not effective in suppressing weeds when intercropped with maize. Leafstripping and detasselling maize at anthesis can be used by smallholder farmers to increase the productivity of maize and cowpea.

Climatic variability and its impacts on agricultural income and households' welfare in southern and Northern Nigeria.

Abstract: This study assessed variability in some weather variables and its impacts on agricultural incomes in northern and southern Nigeria. To achieve these, we combined time series weather variables obtained from some meteorological stations in Nigeria with household cross-sectional data collected by the National Bureau of Statistics (NBS). The descriptive and regression methods were used to analyze the data. The results show high variability in some weather with rainfall exhibiting the highest variability between 1971 and 2003. Impacts of climatic changes on agricultural income and welfare were modeled with climate-related variables like variability indices of annual for 1971-2003, actual annual rainfall data in 2003, time for gathering fuel wood, time for fetching water and season of interview. It was found that agricultural income and welfare in northern part of Nigeria will be more negatively affected by climatic changes than southern part. The study recommended development of alternative energy sources, promotion of irrigate agriculture and skill development for combating adverse climatic changes, among others.

Physico-chemical composition and functional properties of roes from some fresh water fish species and their application in some foods.

Abstract: Physico-chemical and functional properties of fresh roes from four fresh water fish species viz., Catla calla (catla), Cyprinus carpio (carp), Labeo rohita (rohu) and Channa striatus (murrel) were determined to assess the suitability for incorporation in different food products. The protein content ofroes was in the range of 16.6 to 28.2% and fat 3.2 to 9.5%. Phosphorous content was found in the range of 430-1085 mg%. Murrel roes contained lower protein (16.6%), higher fat (9.5%) and exhibited lower foam capacity (9.1%). Foam capacity and foam stability were found to be higher in case of catla roes. Maximum protein solubility of homogenised roes was found at pH 2 and 12. Protein solubility of roes was higher at pH 4 and 8 (50-88%) compared to that of pH 6.5 (40- 60%). Results indicated that the roes could be better utilized as supplements for preparation of various protein and PUF A rich bakery/extruded foods.

Biochemical and PCR-RAPD characterization of Pseudomonas fluorescens produced antifungal compounds inhibit the rice fungal pathogens in vitro.

Abstract: Plant growth-promoting rhizobacterial strains belonging to fluorescent pseudomonads were isolated from the rhizosphere of rice. Among 30 strains that were confirmed as Pseudomonas fluorescens, these P. fluorescens strains was characterized by PCR-RAPD analysis and biochemical methods. Ten exhibited strong antifungal activity against P. oryzae and R. solani mainly through the production of antifungal metabolites.