Gulab N. Jham

Lipid classes, fatty acid composition and triacylglycerol molecular species in crude coffee beans harvested in Brazil

Abstract The lipids of crude coffee beans of Catuai Vermalho, Coffea arabica L. harvested in Brazil have been examined as a part of a broader program on their role for the quality of Brazilian coffee. Triacylglycerols (75%), terpene esters (14%), partial acylglycerols (5%), free fatty acids (1%), free sterols (1.5%), sterol esters (1%) and polar lipids (

Initial studies of mating disruption of the tomato moth, Tuta absoluta (Lepidoptera: Gelechiidae) using synthetic sex pheromone

The potential of the synthetic major component of T. absoluta (Meyrick) sex pheromone for mating disruption was studied in small plots (0.01 hectares) with fresh-market tomato crop. The effects of the application of the sex pheromone 3E,8Z,11Z-14:Ac (from 0 to 80 g a.i./ha) were assessed on male orientation to pheromone baited traps, mating in cages and plant damage. The highest levels of interruption in male orientation (60-90%) were found in plots treated with 35 to 50 g/ha of sex pheromone. However, no treatment with pheromone was capable of significantly reducing the percentage of mined leaflets or bored fruits or the frequency of mating in cages compared to the control plots. The failure in mating disruption technique may be attributed to the composition of the synthetic pheromone, doses used, high pest population density, and mated female migration to the area treated.

Identification of the major fungitoxic component of cinnamon bark oil

The study was done to identify the most active fungitoxic component of cinnamon bark (Cinnamomum zeylanicum) oil that can be used as a marker for standardization of cinnamon extract or oil based natural preservative of stored seeds. Aspergillus flavus and A. ruber were used as test fungi. The hexane extracted crude oil and the hydro-distilled essential oil from cinnamon bark had complete growth inhibition concentration (CGIC) of 300 and 100 µl/l, respectively. Both oils produced three fractions on preparative thin layer silica-gel chromatography plates. The fraction-2 of either oil was the largest and most active, with CGIC of 200 µl/l, but the fungitoxicity was also retained in the other two fractions. The fraction-1 and 3 of the crude oil reduced growth of both the fungal species by 65%, and those of distilled oil by 45% at 200 µl/l. The CGIC of these fractions from both the sources was above 500 µl/l. The gas chromatography and mass spectrometry (GC-MS) of the fraction-2 of the hexane extract revealed that it contained 61% cinnamaldehyde, 29% cinnamic acid, and two minor unidentified compounds in the proportion of 4% and 6%. The GC-MS of the fraction-2 of the distilled oil revealed that it contained 99.1% cinnamaldehyde and 0.9% of an unidentified compound. The CGIC of synthetic cinnamaldehyde was 300 µl/l and that of cinnamic acid above 500 µl/l. The 1:1 mixture of cinnamaldehyde and cinnamic acid had CGIC of 500 µl/l. The data revealed that cinnamaldehyde was the major fungitoxic component of hexane extract and the distilled essential oil of cinnamon bark, while other components have additive or synergistic effects on total fungitoxicity. It is suggested that the natural seed preservative based on cinnamon oil can be standardized against cinnamaldehyde.

Adição de Lipídios na Ração de Vacas Leiteiras: Parâmetros Fermentativos Ruminais, Produção e Composição do Leite

RESUMO - Objetivou-se avaliar o efeito de dois niveis de lipidios (3 e 7%) na dieta de vacas em lactacao e, dentro do nivel de 7% avaliar duas fontes de lipidios (grao de soja moido e oleo de soja), sobre a producao e composicao do leite, os parâmetros ruminais, a atividade de producao de amonia pela microbiota ruminal e o consumo de MS. Foram usadas seis vacas multiparas holandesas, puras e mesticas, com 500 kg de peso corporal, 30 dias pos-parto e producao media de 20 litros de leite/dia, distribuidas em dois quadrados latinos 3x3. Cada periodo experimental teve duracao de 23 dias, sendo 16 dias para adaptacao a dieta e sete dias para coleta de amostras ruminais. A producao de leite foi medida diariamente duas vezes, do 15 o ao 23 o dia de cada periodo experimental, fazendo-se uma amostragem do leite para analises de proteina e gordura. As amostras de liquido ruminal foram coletadas manualmente, por intermedio de sonda esofagica, e filtradas em gaze. As producoes de leite e leite corrigido para 4%, proteina, gordura, lactose, solidos totais, solidos desengordurados e densidade nao foram afetados pelo aumento de lipidios na dieta e nem pelas diferentes fontes de lipidios. Houve efeito depressivo de lipidios sobre a porcentagem de butirato e consumo de MS, sendo que o oleo de soja causou maior efeito. O pH aumentou somente com a inclusao de grao de soja moido na dieta. Os niveis de acetato, propionato, A:P, isobutirato, isovalerato, amonia e atividade de producao de amonia nao sofreram efeito de tratamentos.

Field Trapping of Tomato Moth, Tuta absoluta with Pheromone Traps

Field evaluations demonstrate that the addition of the minor pheromone component (3E,8Z)-tetradecadien-1-yl acetate to the major component (3E,8Z,11Z)-tetradecatrien-1-yl acetate does not significantly increase the trap catches of Tuta absoluta males in the field. The triene acetate itself is highly attractive, catching about 869 ± 255 males per trap in three consecutive nights. The addition of two isomers of the minor component (3E,8Z)-tetradecadien-1-yl acetate, (3E,11Z)-tetradecadienyl-yl acetate and (8Z,11Z)-tetradecadien-1-yl acetate, to the major component (3E,8Z,11Z)-tetradecatrien-1-yl acetate also did not significantly alter the number of the males caught in the traps.

Evaluation of the synthetic major component of the sex pheromone of Tuta absoluta (Meyrick) (Lepidoptera : Gelechiidae)

In wind-tunnel bioassays, dispensers loaded with 1 μg of the synthetic major component (3E,8Z,11Z)-3,8,11-tetradecatrienyl acetate (TDTA) of the sex pheromone emitted by Tuta absoluta (Meyrick) females were found to be highly attractive to conspecific males. Field experiments were conducted to evaluate the efficacy of five trap designs. The best trap, baited with 100 μg of the synthetic sex pheromone caught on average 1200 males per trap per night, while those baited with virgin females caught only 201 males. The male response to this pheromone is restricted to the same early-morning time window during which females exhibit calling behavior. The high biological activity of the synthetic pheromone suggests that it could be useful for pest monitoring and in mating disruption.

Isolation and Identification of the Principal Fungitoxic Component of Turmeric Essential Oil

Abstract The essential oil of turmeric (Curcuma longa L.) rhizomes showed toxicity to seven fungi involved in deterioration of stored agricultural commodities. Depending upon the fungus, in vitro growth inhibition varied from 36%-77% at 0.1%. Aspergillus flavus, Fusarium semitectum, Colletotrichum gloeosporioides and C. musae were most sensitive with growth inhibition of over 70%. The bioautography of the oil produced only one antifungal band representing 40% of the total oil. The fractionation of this band by reverse phase preparative HPLC (high performance liquid chromatography) yielded two peaks, in the proportion of 57.9% and 42.1%. The larger peak had only one compound, which was identified as ar-turmerone by MS (mass spectrometry) and NMR (nuclear magnetic resonance) spectra. The smaller peak contained two compounds, in the proportion of 31% and 69%, which were identified as β-turmer-one and ar-turmerone, respectively. Thus ar-turmerone constituted 87% of the fungitoxic component of the oil. The purified ar-turmerone showed antifungal activity similar to the crude oil.

Seletividade de extratos de nim (Azadirachta indica A. Juss.) ao ácaro predador Iphiseiodes zuluagai (Denmark & Muma) (Acari: Phytoseiidae)

The relative toxicity of the leaf, seed and oil neem cake extracts of Azadirachta indica A. Juss (neem) to the predatory mite Iphiseiodes zuluagai (Denmark & Muma) (Acari: Phytoseiidae) was evaluated. To verify the relative toxicity of these extracts on the predatory mite, discriminating concentrations of the extracts were determined for adult females of the Oligonychus ilicis (McGregor) (Acari: Tetranychidae), through the method of concentration-mortality. Coffee leaf disks with 3.5 cm of the diameter were put floating on water and impregnated with dry residue of the extracts. Concentrations of neem extracts which caused mortality (99%) of O. ilicis, after 72h of exposition, were 277.4; 520.9 e 10.9 mg/ml for leaf, seed and oil neem cake, respectively. The discriminating concentration of extract of oil neem cake for O. ilicis females was highly toxic to I. zuluagai; while extract of leaf and seed were selective to the predatory mite.

Ergosterol accumulation and oil quality changes in stored soybean invaded by Aspergillus ruber (A. glaucus group)

Soybean seed samples inoculated with spores of Aspergillus ruber were stored for 20 to 140 days at 25 ± 1 °C with moisture content varying from 11.3% to 17.7%. Seeds were colonised by the fungus within 20 days at all moisture levels. Ergosterol concentration in seeds increased with time of storage, being slow in samples with moisture content of 11.3% to 13.1% and more rapidly in those with higher moisture content. Free fatty acid (FFA) content also increased following the pattern of ergosterol. Equations were used to predict minimum safe storage period of the seeds at 25 °C. The rise in FFA is due to increase of A. ruber mass within the seed. Fungal growth did not affect fatty acids profiles or iodine index of the extracted oil. The results suggest revision of the present recommendations regarding seed moisture during storage. The FFA concentration of a seed lot can be used as a sensitive indicator of seed deterioration due to storage fungi.

Variability of Lycopersicon hirsutum f. typicum and possible compounds involved in its resistance to Tuta absoluta

1 The resistance of Lycopersicon hirsutum f. typicum and L. esculentum to the leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) was investigated in two experiments. The first experiment assessed the resistance of L. hirsutum f. typicum (accession LA 1777) to T. absoluta, the second assessed the variability of the resistance among plants of this accession.