Effects of gassericins A and T, bacteriocins produced by Lactobacillus gasseri, with glycine on custard cream preservation
Effects of gassericins A and T, bacteriocins produced by Lactobacillus gasseri, with glycine on custard cream preservation
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DOI：
10.3168/jds.2008-1240
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发表时间：
2009-06-01
影响因子：
3.5
通讯作者：
Saito, T.
中科院分区：
文献类型：
--
作者：
Arakawa, K.;Kawai, Y.;Saito, T.
从人类婴儿粪便中分离的加氏乳杆菌LA 39和LA 158分别产生名为加氏菌素A和T的细菌素。这两种gassericin都具有高的热稳定性（121 ℃，10 min），良好的pH耐受性（pH 2-11），以及对许多革兰氏阳性菌，特别是乳酸菌的强杀菌性，因此有望成为有效的食品防腐剂。对12株吉士奶油腐败菌的微孔板抑菌试验表明，gassericin比nisin A具有更广的抑菌谱。虽然gassericins允许革兰氏阴性分离株生长，但在添加甘氨酸的情况下，它们成功地抑制了微孔中所有测试细菌菌株的生长。甘氨酸对除乳酸菌外的许多菌株都有抑菌作用。在实际应用中，通过在使用奶酪乳清、营养蛋白胨和表面活性剂蛋黄卵磷脂改进的食品级培养基中培养来有效地生产加丝菌素A。通过对蜡状芽孢杆菌、乳酸乳球菌、葡萄球菌乳杆菌、无色杆菌和荧光假单胞菌。每毫升含有123个任意单位的gassericin A的奶油冻完全抑制了2种革兰氏阳性菌株的生长。在含有不足量的gassericin A（49任意单位/mL）的奶油中，革兰氏阳性菌株逐渐生长，但通过添加0.5%（wt/wt）甘氨酸而被完全抑制。2株革兰氏阴性菌在不含添加剂的奶油中也没有繁殖，可能是生长环境不适宜所致。本文首次报道了细菌素和甘氨酸的联合作用及其在食品防腐中的应用，为今后在食品工业中的应用提供了参考。
Lactobacillus gasseri LA39 and LA158 isolated from human-infant feces produce bacteriocins named gassericins A and T, respectively. Both gassericins have high heat stability (121 degrees C, 10 min), good pH tolerance (pH 2-11), and strong bactericidality against many gram-positive bacteria, especially lactic acid bacteria, and thus are expected to be effective food preservatives. A microwell plate assay against 12 strains of custard cream spoilage bacteria showed that the gassericins had broader antibacterial spectra than nisin A. Although the gassericins allowed gram-negative isolates to grow, they successfully inhibited the growth of all tested bacterial strains in microwells with the addition of glycine. Glycine was bacteriostatic against many strains except lactic acid bacteria. For practical use, gassericin A was efficiently produced by cultivation in a food-grade medium improved using cheese whey, nourishing proteose peptone, and surfactant yolk lecithin. The practical preservative effect of gassericin A and glycine was verified from the viability of 4 isolated strains, Bacillus cereus, Lactococcus lactis ssp. lactis, Achromobacter denitrificans, and Pseudomonas fluorescens, in custard creams. Custard cream containing 123 arbitrary units of gassericin A per milliliter entirely growth-inhibited the 2 gram-positive strains. In custard cream containing an insufficient amount of gassericin A (49 arbitrary units/mL), the gram-positive strains gradually grew but were completely inhibited by the addition of 0.5% (wt/wt) glycine. The 2 gram-negative strains did not multiply even in the additive-free custard cream, probably because of the unsuitable growth environment. This is the first report showing the combined effect of bacteriocin and glycine and their application for food preservation, which may be helpful for future use in the food industry.