Full text
| |
| Author(s): |
Alessandra de Cassia Romero
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB) |
| Defense date: | 2013-03-15 |
| Examining board members: |
Adibe Luiz Abdalla;
Ives Cláudio da Silva Bueno;
Marisa Aparecida Bismara Regitano d\'Arce;
Evandro Maia Ferreira;
Simone Mendonça
|
| Advisor: | Adibe Luiz Abdalla |
| Abstract | |
The growing demand for sustainable and clean energy sources has increased the search of alternative raw materials for the production of biofuels. Castor-oil plant, jatropha and cotton seeds are among the plant resources that are not used for food although they have high level of oil for biodiesel production and might have considerable potential to use their residues to feed ruminants. However, for these \"residues\" to achieve status of co-products it is necessary to evaluate its toxicity before using them at safe levels or to perform its detoxification. This study aimed to measure the content of gossypol, ricin and phorbol esters bioactives molecules in cottonseed, castor and jatropha meals respectively in order to evaluate the potential of the use of these co-products to feed ruminants, considering the action of these biomolecules in ruminal fermentation in vitro into different substitution levels of soybean meal in the concentrate. The experimental design was completely randomized; one level of a meal by replacing 22,2% of soy in its concentrate and three levels by adding biomolecules extracted from meals simulating the replacement of 33,3, 66,6 and 100% of soy in its concentrate in the same diet base (control) of others treatment in order to evaluate differences of effects of biomolecules in natura both in a meal or extracted. The results were analyzed by linear and quadratic regression, ANOVA and Dunnett´s test for comparison of averages of treatments compared to control. The HPLC methodologies to quantify the biomolecules were adapted and validated. The biomolecules\' concentrations were within the values were quoted in the literature and both the gossypol as ricin could be added in the feeding of ruminants at the levels proposed in this report, providing intake levels below those quoted as toxic in literature. Likewise, the gas production in rumen fermentation in vitro showed no effects of biomocules on rumen microbial. According to the literature, the jatropha levels proposed could cause toxicity by the content of phorbol esters ingested. In the bioassay with jatropha, effects on methane efficiency rate were observed when 22,2% of meal were added, suggesting that phorbol esters are bioactives only in meal in natura or even the presence of other toxic compound, alone or in synergy with phorbol esters, might have affected the ruminal microflora. The viability of cottonseed and castor meal in natura inclusion was not denied by this report, however, it is extremely necessary to consider their concentration of biomolecules and correct animal handling. For the use of jatropha in natura at any level of addition further studies are still needed on the toxicity of phorbol esters in meal in natura and its possible synergy with other toxic compounds. The identification and quantification of phorbol esters before and after detoxification treatment has still being a main barrier to jatropha meal becomes a co-product of animal nutrition (AU) | |