బయోప్రాసెసింగ్ & బయోటెక్నిక్స్ జర్నల్

The substitution of synthetic chemical pesticides has become a priority in agriculture and the induction of plant resistance by protein hydrolysates may offer a sustainable alternative. The protein source, method and degree of hydrolysis, as well as the amino acid and peptide composition may affect the efficacy of protein hydrolysates in protecting plants against pathogens. The aim of this work was to clarify the effect of enzymatic and acid hydrolysis on different plant protein sources (soybean, rapeseed and guar protein meal), in terms of efficacy against the powdery mildew of courgette plants (caused by Podosphaera xanthii). The enzymatic hydrolysates were obtained by incubating each protein suspension with a measured amount of Alcalase or Flavourzyme at 50°C for 24 h, in order to obtain an enzyme/substrate ratio of 1% and 50%. The chemical hydrolysates were obtained by acid hydrolysis using 6 N H2SO4 at 121°C for 15 min (6N A), or at 100°C for 8 h (6N B) respectively. Preventive foliar treatments with guar hydrolysates produced with both enzymatic (Alcalase 50% E/S ratio) and chemical (6N B) hydrolysis significantly reduced disease symptoms compared to the non-hydrolysed protein source. A positive correlation was found between efficacy and the degree of hydrolysis of guar acid hydrolysates, suggesting that the hydrolysis method may enhance the functional properties of the original protein source. In addition, positive correlations were found between the efficacy of guar hydrolysates and concentrations of specific peptides and amino acids. In conclusion, our results showed that the biocontrol effect of plant protein hydrolysates was related to the original protein source and two specific hydrolysis processes improved the functional properties of guar, producing peptide fragments and free amino acids that may be involved in the regulation of innate immune response in plants.

In the test to select hybrid F1generation of wild boar (wild boar ♂ × BAM ♀), local pig breeds (BAM and HZP) and YOK were adopted single factor experimental design, under the same nutrient levels, production performance, slaughter performance and meat quality characteristics of different varieties of pigs were studied. The results showed that a daily gain of F1 and BAM were significantly lower than YOK (P<0.05), while daily gain of HZP was significantly lower than another groups (P<0.01), and YOK fed remuneration and lean meat were the highest. Slaughter rate, carcass length, pH, water loss rate, storage loss and muscle fiber diameter of HZP were relatively lower, but meat score and marble texture were relatively higher. From AA and FA contents of the muscle, the pig's main UAA content of HZP was 23.91 g, accounting for 34.50% of the total AA contents, second only to the F1 hybrid, and the content of UFA was the highest, and UFA/SFA was 1.30. Compared with another breeds of pigs, HZP had good meat quality, The compounds which may contribute to the flavor of pork were 3-methyl-1-butanol, 1-nonanal, Octanal, Hexanal, 2-pentyl-furan, 1-penten-3-one, N-morpholinomethyl-isopropyl-sulfide, Methyl butyrate and (E,E)-2,4-decadienal. In conclusion, the volatile compounds in pork belong to several classes and the highest relative amount of volatile compounds was found in BAM.