羊骨酶解液的植物乳杆菌发酵

Fermentation of sheep bone enzymatic hydrolysates by Lactobacillus plantarum

摘要:

为进一步提高羊骨酶解液的营养价值和生物利用度，探讨乳酸菌发酵对钙离子释放、短肽形成以及酶解液抗氧化活性的影响。首先从7株乳酸菌中筛选出了产蛋白酶能力最强的植物乳杆菌，接种羊骨酶解液，以发酵液中Ca2+浓度为指标，响应面法优化得到发酵工艺：酶解液中添加1%的麦芽糖，调节起始pH为5.5，以4%接种量接种驯化好的植物乳杆菌，37 ℃摇床发酵14 h。发酵过程中，植物乳杆菌活菌数与Ca2+含量 (R=0.495，P<0.01)和短肽得率 (R=0.655，P<0.01) 呈极显著正相关，而多肽生成量与短肽得率呈负相关 (R=-0.013)。发酵液中的Ca2+浓度 (P<0.05)、水解度 (P<0.01)、短肽得率 (P<0.01)、羟脯氨酸含量 (P<0.01) 均显著高于酶解液 (P<0.01)，植物乳杆菌活菌数达到94.6×108 CFU/mL。发酵还可使酶解液对DPPH、·OH、O2-·三种自由基的清除能力显著提高 (P<0.01，P<0.05)。综上所述，以植物乳杆菌发酵羊骨酶解液可进一步促进骨钙的转化和胶原短肽的生成并显著提高其体外抗氧化能力，短肽和Ca2+反过来促进植物乳杆菌的繁殖，增强了酶解液的益生功能，乳酸菌产生的维生素、胞外多糖等物质使羊骨酶解液更富营养。

Abstract:

In order to improve the nutritional value and bio-availability of sheep bone enzymatic hydrolysates, we tried to ferment the hydrolysates with lactic acid bacteria (LAB) to enhance free Ca2+, to generate oligopeptide and antioxidative activity. First, we isolated 7 LAB strains from commercial starters and selected Lactobacillus plantarum as the starter for its highest protease-producing ability. The content of released Ca2+ was evaluated when the fermenting conditions were optimized by the method of responsive surface design. When supplemented with 1% maltose and inoculated 4% L. plantarum, at initial pH 5.5 and 37 ℃ for 14 h, Ca2+ content in the hydrolysates increased significantly (P<0.05), as well as the generation oligopeptide (P<0.01), and the content of hydroxyproline (P<0.01). The count of L. plantarum in the fermented hydrolysates reached to 94.6×108 CFU/mL. L. plantarum fermentation significantly enhanced the ability to scavenge free radicals DPPH, ·OH and O2-· (P<0.01, P<0.05). Therefore, fermenting sheep bone hydrolysates by L. plantarum can increase free Ca2+, oligopeptide and antioxidative ability.