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The fruits of Balanites aegyptiaca, a wild savannah tree, constitute a promising source of steroidal sapogenins, chemicals in demand by the pharmaceutical industry, in addition to an untapped source of an edible fixed oil. Large guantity of the fruit (ca. 400 000 tons per annum) are traditionally collected and marketed in Sudan due to their edible mesocarp. This study is concerned with accumulation of the fixed oil as well as of steroidal sapogenins in 11 fruit developmental stages, from the young immature to the fully ripe, dry stages. The fruits were separated into "kernels" and combined "epicarp+ mesocarp" tissues. An infra-red spectrophotometric method was used for sapogenin quantification. Total sapogenin contents expressed per tissue was 0.5 mg in kernels and 2.5 mg in "epicarp=mesocarp" in the first stage (S1). Thereafter, these values rose sharply in later fruit developmental stages so that by stage S7 (a mature but still green stage), they contained maximum values of 22.0 and 60.0 mg/tissue, respectively. Similarly, balanites kernel oil (BKO) dramatically increased in amount with fruit development; from < 5.0% in the first two very young stages to over 45.0% of kernel dry weight by stages 7 and 8. Thus, harvesting fruits at the still green 7th stage would minimize losses of the dry, sapogenin-rich epicarp encountered during traditional harvesting and handling of dry fruits. "Epiarp+mesocarp" tissue contained both 25a and 25b sapogenins, the proportion of 25b increased with fruit maturation. On the other hand, kernel tissue contained only 25a (diosgenin type) sapogenin till the very late fruit stage, when plastid degradation occurred. Linoleic acid was the major fatty acid of balanites kernel oil in all fruit developmental stages. Linolenic and palmitoleic acids were present in the kernel oil of very young fruits but disappeared with the degradation of plastid-membrane lipids on further fruit maturation and desication. [ABSTRACT FROM AUTHOR]

Problem statement: Certain basil essential oils were claimed to have a larvicidal activity towards mosquito's larvae. To test this claim the essential oils of four accessions of basil grown in Sudan were selected and tested for Anopheles larvae. Malaria is the major health problem in the Sudan and the whole country is now considered endemic, with varying degrees, about 35,000 deaths every year due to malaria. Anopheles mosquito is the major vector of malaria disease in Sudan. Search for larvicidal active compound(s) is one of several attempts to fine effective and affordable ways to control this mosquito. To determine the toxic effects of basil essential oils extracted by steam distillation against Anopheles larvae. Approach: For the larvicidal bioassay, three concentrations (100, 300, 500 ppm) of essential oil solutions of four basil accessions were prepared; 1 mL of ethanol was used to solubilize the oil in water (999 mL). In each concentration of oil solution were inserted 20 larvae (third instars). A set of controls using 0.1% ethanol and untreated sets of larvae in (tap) water, were also run for comparison. Data were evaluated through regression analysis, from the regression line; the [LC.sub.50] values were read. The active ingredients were separated and/ or identified by TLC, IR and GC-MS. Results: Larvicidal activity of the essential oils is varied, lasted for about 9 h and thereafter decreased, [LC.sub.50] values ranging from 190-300 ppm. Linalool, geraniol and eugenol are active components of basil essential oil against Anopheles larvae. Two accessions were caused 100% mortality at a concentration range 300-500 ppm for 3 h. Conclusion: These results indicated that basil essential oils have larvicidal activity towards Anopheles larvae. Therefore, could be affordable way to control this mosquito. Key words: Basil, Ocimum basilicum, essential oil, larvicidal activity, Anopheles mosquito, INTRODUCTION Mosquitoes are insects belonging to the order Diptera and as other true flies; develop through four distinct life stages-egg, larva, pupa and adult. It is hard to comprehend the [...]

A cDNA isolated from the prymnesiophyte micro-alga Isochrysis galbana, designated IgASE1, encodes a fatty acid elongating component that is specific for linoleic acid (C18:2n-6) and α-linolenic acid (C18:3n-3). Constitutive expression of IgASE1 in Arabidopsis resulted in the accumulation of eicosadienoic acid (EDA; C20:2n-6) and eicosatrienoic acid (ETrA; C20:3n-3) in all tissues examined, with no visible effects on plant morphology. Positional analysis of the various lipid classes indicated that these novel fatty acids were largely excluded from the sn-2 position of chloroplast galactolipids and seed triacylglycerol, whereas they were enriched in the same position in phosphatidylcholine. EDA and ETrA are precursors of arachidonic acid (C20:4n-6), eicosapentaenoic acid (C20:5n-3), and docosahexaenoic acid (C22:6n-3) synthesized via the so-called ω6 Δ8 desaturase and ω3 Δ8 desaturase biosynthetic pathways, respectively. The synthesis of significant quantities of EDA and ETrA in a higher plant is therefore a key step in the production of very long chain polyunsaturated fatty acid in oil-seed species. The results are further discussed in terms of prokaryotic and eukaryotic pathways of lipid synthesis in plants. [ABSTRACT FROM AUTHOR]