Kuhnen Shirley, Moacyr Juliana R, Mayer Jaqueline K, Navarro Bruno B, Trevisan Rafael, Honorato Luciana A, Maraschin Marcelo, Pinheiro Machado Filho Luiz C
Laboratório de Bioquímica e Morfofisiologia Animal, CCA, Departmento de Zootecnia e Desenvolvimento Rural, Universidade Federal de Santa Catarina, Florianópolis, SC, 88034-001, Brazil.
J Sci Food Agric. 2014 Dec;94(15):3110-7. doi: 10.1002/jsfa.6654. Epub 2014 Apr 30.
Phenolic compounds are widely present in forage. However, few studies have been carried out to investigate the presence of these compounds in animal products such as milk. In this study, the total phenolic content (TPC) and ferric reducing-antioxidant power (FRAP) of milk produced under agroecological and conventional management systems in southern Brazil were determined. Three systems were compared: (a) agroecological, with intensive rotational grazing, also known as Voisin grazing (ECO); (b) semi-intensive conventional (SIC); and (c) conventional grazing (CGR) (n = 8 per group). Pastures with distinct and more diverse botanical composition were observed on the ECO farms.
Significantly (P < 0.05) lower amounts of TPC were found in agroecologically produced milk in autumn and summer and the CGR system showed the highest FRAP value (P < 0.05) for the samples collected in autumn. Positive correlations where found between the TPC and FRAP values obtained for the milk samples (0.198, P < 0.05), milk FRAP and forage TPC values (0.344, P < 0.05), and the TPC and FRAP values obtained for the forage (0.70, p < 0.01). PCA applied to the UV spectra dataset (200-350 nm) clearly distinguished the samples collected from the ECO system in the winter.
Our results revealed that, under the conditions prevalent in southern Brazil, since the cows were allowed to graze in all of the systems, the TPC and antioxidant capacity of the milk samples showed minimal variation. However, since the forage TPC and FRAP values for the milk were correlated, TPC appears to be a promising variable for the purpose of monitoring forage prior to its selection aimed at enhancing the antioxidant activity of milk.
酚类化合物广泛存在于饲料中。然而，针对这些化合物在牛奶等动物产品中的存在情况，开展的研究较少。本研究测定了巴西南部农业生态管理系统和传统管理系统下生产的牛奶的总酚含量（TPC）和铁还原抗氧化能力（FRAP）。比较了三种系统：（a）农业生态系统，采用集约轮牧，也称为瓦赞放牧（ECO）；（b）半集约传统系统（SIC）；（c）传统放牧系统（CGR）（每组n = 8）。在ECO农场观察到具有不同且更为多样植物组成的牧场。
秋季和夏季农业生态生产的牛奶中TPC含量显著较低（P < 0.05），CGR系统在秋季采集的样本中显示出最高的FRAP值（P < 0.05）。牛奶样本的TPC和FRAP值之间存在正相关（0.198，P < 0.05），牛奶FRAP和饲料TPC值之间存在正相关（0.344，P < 0.05），饲料的TPC和FRAP值之间也存在正相关（0.70，P < 0.01）。应用于紫外光谱数据集（200 - 350 nm）的主成分分析（PCA）清楚地区分了冬季从ECO系统采集的样本。
我们的结果表明，在巴西南部普遍存在的条件下，由于所有系统中的奶牛都被允许放牧，牛奶样本的TPC和抗氧化能力显示出最小的变化。然而，由于牛奶的饲料TPC和FRAP值相关联，TPC似乎是一个有前景的变量，可用于在选择饲料以提高牛奶抗氧化活性之前监测饲料情况。
