Antioxidant and pro-oxidant actions of resveratrol on human serum albumin in the presence of toxic diabetes metabolites: Glyoxal and methyl-glyoxal

Methylglyoxal (MGO) and glyoxal (GO) are attracting considerable attention because of their role in the onset of diabetes symptoms. Therefore, to comprehend the molecular fundamentals of their pathological actions is of the utmost importance. In this study, the molecular interactions between resveratrol (RES) and human serum albumin (HSA) and the ability of the stilbene to counteract the oxidative damage caused by pathological concentrations of MGO and GO to the human plasma protein, was assessed. The oxidation of Cys34 in HSA as well as the formation of specific protein semialdehydes AAS (α-aminoadipic), GGS (γ-glutamic) and the accumulation of Advanced Glycation End-products (AGEs) was investigated. Resveratrol was found to neutralize both α-dicarbonyls by forming adducts detected by HESI-Orbitrap-MS. This antioxidant action was manifested in a significant reduction of AGEs. However, RES-α-dicarbonyl conjugates oxidized Cys34 and lysine, arginine and/or proline by a nucleophilic attack on SH and ε-NH groups in HSA. The formation of specific semialdehydes in HSA after incubation with GO and MGO at pathological concentrations was reported for the first time in this study, and may be used as early and specific biomarkers of the oxidative stress undergone by diabetic patients. The pro-oxidative role of the RES-α-dicarbonyl conjugates should be further investigated to clarify whether this action leads to positive or harmful clinical consequences. The biological relevance of human protein carbonylation as a redox signaling mechanism and/or as a reflection of oxidative damage and disease should also be studied in future works.

Shelf life of cooked goat blood sausage prepared with the addition of heart and kidney

This study focused on the effect of two packaging formats (vacuum packaging and over-wrap packaging) on the shelf life of cooked sausage prepared with blood, heart, kidney and goat meat fragments under storage at 4±1°C for a period of 90 days. The storage time and type of packaging significantly affected the chemical (pH, moisture, protein and TBARS number), physical (shear force) and microbial (mould and yeast) parameters of cooked sausage. Vacuum packaging maintained the microbiological and chemical qualities of cooked goat blood sausage for a longer period of time (63 days) compared to over-wrap packaging (41 days) and could be a viable alternative to refrigerated storage of the product for quality maintenance.

Castration and slaughter age effects on nutritive value of the "mestiço" goat meat

Groups of castrated male and intact "mestiço" goats were slaughtered at 175, 220, 265 and 310 days of age. After slaughter the carcasses were chilled for 24 h at 2°C, and pH, Aw, Ca, Fe, P, moisture, ash, protein and fat were determined on the total lean. Slaughter age had a significant (p<0.01) effect on moisture, protein, iron, calcium and pH. Calcium content was influenced by castration and the slaughter age×castration interaction was significant (p<0.01) for iron content. Meat from castrated males contained less moisture and protein and more fat, ash, iron and calcium than did meat from intact males. The fat, protein and iron content increased with increasing slaughter age, while moisture decreased. Composite results indicate slaughtering "mestiço" goats at 310 days exert favourable effects on the parameters investigated. ©

Castration and slaughter age effects on panel assessment and aroma compounds of the "mestiço" goat meat

Cooked meat from castrated male and intact "mestiço" goats slaughtered at 175, 220, 265 and 310 days of age, were analysed by panellists and GC-MS. Slaughter age had a (P<0.05) effect on organoleptic qualities of goat meat. Scores for sensorial attributes were not different (P<0.05) for intact and castrated goats. A total of 87 compounds were identified and a further 21 were partially characterized by GC-MS. Hydrocarbons were presented in the highest relative amounts and all aroma isolates were dominated by products of lipid degradation. Total relative abundance of volatiles was identified at higher levels in the cooked meat from castrated goats than from entires. Meat from goats slaughtered at first age (175 days) was preferred by panellists and was found to have the lowest number of volatiles and total relative abundance.

Efeito do feno de flor-de-seda sobre a carcaça e constituintes corporais de cordeiros morada nova

Avaliou-se a utilização do feno de flor-de-seda (Calotropis procera SW) (FFS) em cordeiros Morada Nova em confinamento. Utilizaram-se 32 cordeiros com peso vivo inicial de 12,72±1,99 kg e de abate 19,29±2,25 kg, distribuídos em delineamento inteiramente casualizado com 4 tratamentos (0%, 15%, 30% e 45% de FFS) e oito repetições. O aumento dos níveis de FFS diminuiu a conformação da carcaça (2,31; 2,58; 2,17; 1,81 pontos), perímetro da coxa (33,38; 32,17; 32,17; 30,00 cm), compacidade da carcaça (0,18; 0,18; 0,17; 0,15 cm), meia carcaça reconstituída (4,52; 4,63; 4,43; 3,69 kg), lombo (0,66; 0,69; 0,64; 0,50 kg), paleta (0,83; 0,86; 0,80; 0,67 kg) e costela (1,13; 1,09; 1,05; 0,84 kg), mas aumentou o linearmente os pesos da perna (30,98; 30,81; 31,60; 34,47 kg) e a gordura mesentérica (1,02; 0,65; 1,17; 1,42%). A inclusão de FFS na dieta promoveu efeito sobre as medidas da carcaça e seus rendimentos, assim como o rendimento dos cortes comerciais e componentes não-cons-tituintes da carcaça. Estima-se que a inclusão de até 30% de FFS na dieta é relevante na manutenção das boas características de carcaça em regiões onde se tenha oferta desta forragem.