School of Animal Technology and Innovation, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
School of Food Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
Poult Sci. 2022 May;101(5):101776. doi: 10.1016/j.psj.2022.101776. Epub 2022 Feb 11.
Carnosine enrichment of slow-growing Korat chicken (KRC) meat helps differentiate KRC from mainstream chicken. We aimed to investigate the effects of β-alanine and L-histidine supplementation on the carnosine synthesis in and quality and secondary structure of proteins in slow-growing KRC meat. Four hundred 21-day-old female KRC were used, and a completely randomized design was applied. The chickens were divided into 4 experimental groups: basal diet (A), basal diet supplemented with 1.0% β-alanine (B), 0.5% L-histidine (C), and 1.0% β-alanine combined with 0.5% L-histidine (D). Each group consisted of 5 replicates (20 chickens per replicate). On d 70, 2 chickens per replicate were slaughtered, and the levels of carnosine, anserine, and thiobarbituric acid reactive substances were analyzed. Biochemical changes were monitored using synchrotron radiation-based Fourier transform infrared microspectroscopy; 5 chickens per replicate were slaughtered, and the meat quality was analyzed. Statistical analysis was performed using ANOVA and principal component analysis (PCA). Group D chickens exhibited the highest carnosine meat content, followed by those in groups B and C. However, amino acid supplementation did not affect anserine content and growth performance. Higher carnosine levels correlated with increasing pH and decreasing drip loss, cooking loss, shear force, and lipid oxidation. PCA revealed that supplementation with only β-alanine or L-histidine was related to increased content of β-sheets, β-turns, and aliphatic bending groups and decreased content of α-helix groups. This study is the first to report such findings in slow-growing chicken. Our findings suggest that KRC can synthesize the highest carnosine levels after both β-alanine and L-histidine supplementation. Higher carnosine contents do not adversely affect meat quality, improve meat texture, and alter the secondary structures of proteins. The molecular mechanism underlying carnosine synthesis in chickens needs further study to better understand and reveal markers that facilitate the development of nutrient selection programs.
肌肽富集的慢速生长 Korat 鸡肉（KRC）有助于区分 KRC 和主流鸡肉。我们旨在研究β-丙氨酸和 L-组氨酸补充对慢速生长 KRC 肉中肌肽合成和蛋白质质量及二级结构的影响。使用 400 只 21 日龄雌性 KRC，采用完全随机设计。鸡分为 4 个实验组：基础日粮（A）、基础日粮添加 1.0%β-丙氨酸（B）、0.5%L-组氨酸（C）和 1.0%β-丙氨酸加 0.5%L-组氨酸（D）。每个组包括 5 个重复（每个重复 20 只鸡）。在第 70 天，每个重复宰杀 2 只鸡，分析肌肽、鹅肌肽和硫代巴比妥酸反应物的水平。使用基于同步辐射的傅里叶变换红外微光谱监测生化变化；每个重复宰杀 5 只鸡，分析肉质。使用方差分析和主成分分析（PCA）进行统计分析。D 组鸡的肌肽肉含量最高，其次是 B 组和 C 组。然而，氨基酸补充并不影响鹅肌肽含量和生长性能。较高的肌肽水平与 pH 值升高和滴水损失、蒸煮损失、剪切力和脂质氧化降低相关。PCA 显示，仅补充β-丙氨酸或 L-组氨酸与β-折叠、β-转角和脂肪弯曲基团含量增加以及α-螺旋基团含量减少有关。本研究首次报道了慢速生长鸡中存在这种情况。我们的研究结果表明，KRC 在补充β-丙氨酸和 L-组氨酸后可以合成最高水平的肌肽。较高的肌肽含量不会对肉质产生不利影响，可改善肉质纹理，并改变蛋白质的二级结构。需要进一步研究鸡中肌肽合成的分子机制，以更好地理解和揭示促进营养选择计划发展的标记物。
