CONTENT AND COMPOSITION OF LIPID PRODUCED BY CHLORELLA VULGARIS FOR BIODIESEL PRODUCTION

This study aims at investigating the lipid profile of Chlorella vulgaris to determine its suitability as an alternative bio-fuel source. Chlorella vulgaris (stock culture UTEX 259) was sub-cultured at laboratory scale. The cells were kept in 250ml, 500ml, and 1000ml Erlenmeyer flasks with 200ml, 300ml, and 600ml of medium respectively and shaken occasionally in Bold Basal Medium with initial pH value 7 at the temperature of 22+ 30c with constant light intensity for the culture medium which was not more than 2500 lux on a 16:8 light to dark cycle for 7 weeks. The Chlorella vulgaris cells were harvested and the oil extracted. The percentage lipid content was determined by soxhlet extraction and was shown to be 25%. The GC-MS analysis of the transesterified oil showed this lipid profile; nonanoic acid, decanoic acid, palmiltic acid, stearic acid ,oleic acid, linoleic acid with this  chain length C9:0,10:0,16:0,18:0,18:1,18:2 respectively. The percentage unsaturated fatty acid for nitrogen rich media and nitrogen deprived media were 79.22% and 74.2% respectively while the percentage saturated fatty acids were 20.2% and 25.8% respectively. This study shows that Chlorella vulgaris is a suitable candidate for biodiesel production because the lipid profile, lipid composition and level of unsaturation meets requirement of oil suitable for biodiesel production. Key words: Chlorella vulgaris , lipids, oleic acid ,bio-fuel

Descriptive and Vegetative Characterization of fifteen ecotypes of Snake Gourd (Trichosanthes cucumerina L.) in Nigeria

The descriptive and vegetative characterization of fifteen ecotypes of Trichosanthes cucumerina L (snake gourd) in Nigeria was carried out. The field study was done in two locations Markurdi and Umudike to evaluate the descriptive and vegetative characters of fifteen ecotypes of T. cucumerina from Middle Belt of the country, the South-South, South Eastern part and South Western part of Nigeria. Randomized Completed Block Design was adopted for the experiment at the exploration farm of Michael Okpara University of Agriculture, Umudike and Federal University of Agriculture, Makurd at the same growing season. Descriptive and vegetative analysis was done using Minitab 16. The qualitative vegetative characteristic of snake gourd accessions vigour levels ranged from low, moderate and high. Leaf colour was from deep/pale/light green, stem colour was light, pale and deep green. The mean of the vegetative characters ranged from 2.7660-1575 ±0.48-99; cumulative variation percentage 7.65-64.75;. The germination percentage of all the accessions was significant (p<0.05). CRS – IKM (100+00), Osu – OSH – 2 (91.67±4.82).EKT – OYE was higher than Ben-MKDI (58.36±8.34). The plant height among the accessions was not significant, block was significant (P≤0.05). Leaf sizes (cm) of all the accessions were not significant (P>0.05), while main vine length (cm) at 5% probability was not significant and their treatment interaction was insignificant (P>0.05). The main vein length was highest in ABI-UKW with 636.0±164.0, followed by EKI-OYE 514.0±84.3 and least from RIV-ELE 275.7±26.4. The fruit colour at ninety days (90) of ten (10) accessions of snake guard was orange green or strip orange green and remaining accessions was milky green or light green. The fruit shape was long, thick and cylindrical. The seed colour was speckled russet

Comparison of transcriptome-derived simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers for genetic fingerprinting, diversity evaluation, and establishment of relationships in eggplants

[EN] Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers are amongst the most common markers of choice for studies of diversity and relationships in horticultural species. We have used 11 SSR and 35 SNP markers derived from transcriptome sequencing projects to fingerprint 48 accessions of a collection of brinjal (Solanum melongena), gboma (S. macrocarpon) and scarlet (S. aethiopicum) eggplant complexes, which also include their respective wild relatives S. incanum, S. dasyphyllum and S. anguivi. All SSR and SNP markers were polymorphic and 34 and 36 different genetic fingerprints were obtained with SSRs and SNPs, respectively. When combining both markers all accessions but two had different genetic profiles. Although on average SSRs were more informative than SNPs, with a higher number of alleles, genotypes and polymorphic information content (PIC), and expected heterozygosity (He) values, SNPs have proved highly informative in our materials. Low observed heterozygosity (Ho) and high fixation index (f) values confirm the high degree of homozygosity of eggplants. Genetic identities within groups of each complex were higher than with groups of other complexes, although differences in the ranks of genetic identity values among groups were observed between SSR and SNP markers. For low and intermediate values of pair-wise SNP genetic distances, a moderate correlation between SSR and SNP genetic distances was observed (r(2) = 0.592), but for high SNP genetic distances the correlation was low (r(2) = 0.080). The differences among markers resulted in different phenogram topologies, with a different eggplant complex being basal (gboma eggplant for SSRs and brinjal eggplant for SNPs) to the two others. Overall the results reveal that both types of markers are complementary for eggplant fingerprinting and that interpretation of relationships among groups may be greatly affected by the type of marker used.This work has been funded by European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No 677379 (G2P-SOL project: Linking genetic resources, genomes and phenotypes of Solanaceous crops) and by Spanish Ministerio de Economia y Competitividad and Fondo Europeo de Desarrollo Regional (Grant AGL2015-64755-R from MINECO/FEDER). Pietro Gramazio is grateful to Universitat Politecnica de Valencia for a pre-doctoral contract (Programa FPI de la UPV-Subprograma 1/2013 call). Mariola Plazas is grateful to Spanish Ministerio de Economia, Industria y Competitividad for a post-doctoral grant within the Juan de la Cierva-Formacion programme (FJCI-2015-24835).Gramazio, P.; Prohens Tomás, J.; Borras, D.; Plazas Ávila, MDLO.; Herraiz García, FJ.; Vilanova Navarro, S. 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Associated microbial contaminants in in-vitro micropropagation of sweet potato (Ipomoea batatas l)

Studies were carried out to determine the microbial contaminants associated with in-vitro micropropagation of Ipomea batatas (sweet potato). The contaminants were found to be mostly fungal organisms, Aspergillus Spp (62%), Penicillum Spp. (31%), Fusarium Spp. (5%) and Alternaria Spp.(2%). Bacterial contamination was insignificant compared to the fungal population. Aspergillus Spp were the dominant contaminants affecting this crop in vitro. Stunted growth, chlorosis and necrosis of the leaves as well as death of propagules were some of the effects of the contaminants on the performance of the plant in vitro. Minimal conditions for managing the plant in vitro to eliminate contaminations were also suggested. The implications of these findings in the production of disease free propagules of Ipomea batatas were discussed.Keywords: Ipomoea batatas, sweet potato, micro-propagation, microbial contaminants, fung

Quality assessment of drinking water from different sources in Lafia, Nassarawa State, Nigeria

One hundred and twenty four (124) samples of drinking water from different sources in Lafia and its environs were investigated during the months of February to June 2008. The city and its environs were divided into seven zones and samples of water collected from each zones analyzed for physical and microbial quality. The water sources included hand dug wells, boreholes, streams a river. Treated pipe borne water, sachet water and water sold in open containers were also investigated. Standard plate count technique, multiple tube fermentation technique, and membrane filtration technique were employed in determining the microbial quality of the water. The study showed uniform temperature range of 27.5 to 320C in all the zones. The pH at all the stations ranged from 4.9 recorded for Ombi stream to 6.9 recorded for hand dug well from zone C and were within the acceptable standard range for drinking water. Color values range from 6 to 25 hazen, while turbidity ranged from 1.5 NTU for sachet water to 15 NTU for River Amba. The bacterial counts revealed total heterotrophic bacteria range of 12 cfu/ml to too numerous to count. Coliform were present in all sources except sachet and borehole water. E. coli, Aerobacter aerogenes and fecal streptococci were present. E. coli counts of 8 cfu/ml were obtained in hand dug well and 61 cfu in Ombi stream. Yeast (Candida spp), filamentous fungi, the protozoa (Amoeba spp and Paramecium spp), algae, particularly Spirogyra spp were detected in hand dug wells, the three streams and River Amba. The detection of these organisms in dinking water is an indication of the unsuitability of the water sources. Protection of water sources, regular monitoring of drinking water supplies and enforcement of good sanitation habit are  recommended for the study area.Keywords: Drinking water, bacterial count, coliform, heterotrophic bacteria, microbial qualit