不同条件对两株乳酸菌降解生物胺的影响

为探究从新疆熏马肠中分离出的植物乳杆菌和唾液乳杆菌在不同环境条件下降解生物胺的效果,通过高效液相色谱(High Performance Liquid Chromatography,HPLC)检测两株菌在不同条件下(生物胺浓度、初始pH、温度、NaCl浓度和乙醇浓度)降解生物胺的情况。结果表明:当生物胺浓度在200~300 μg/mL时两株菌生物胺降解能力基本达到最大,而当生物胺浓度大于300 μg/mL时两株菌降解生物胺的能力逐渐下降,但唾液乳杆菌(Lactobacillus salivarius)对生物胺的降解能力显著高于植物乳杆菌(Lactobacillus plantarum)(p<0.05),分别在pH为6.5和7.0时对大多数生物胺具有较高的降解能力;两株菌均在32~37 ℃温度范围内对生物胺有较好的降解效果;当NaCl浓度达到8%,乙醇浓度达到4.5%时,两株菌对生物胺的降解活性被强烈抑制。可见本研究中的唾液乳杆菌相对于植物乳杆菌更适合作为商业发酵剂,具有更好的降解生物胺的特性。

Impact of Different Conditions on Biodegradation of Biogenic Amines by Two Lactic Acid Bacteria Strains

To explore the degradation of biogenic amines by Lactobacillus plantarum and Lactobacillus salivarius in different circumstances which had been isolated from from Xinjiang smoked horsemeat sausage. High performance liquid chromatography(HPLC)was used to detect the degradation of biogenic amines by the two strains in different conditions(biogenic amines concentration,initial pH,temperature,NaCl and ethanol concentration). The results showed that when the concentration of biogenic amines at 200~300 μg/mL,the bioamine degradation capacity of the two bacterial strains reached the maximum basically. However,the ability of the two bacterial strains to degrade biogenic amines gradually decreased when the concentration of biogenic amines was more than 300 μg/mL,but the ability of Lactobacillus salivarius to degrade biogenic amines was significantly higher than Lactobacillus plantarum(p<0.05),which had higher biogenic amines degrading activity at pH6.5 and 7.0,respectively. In the environment of temperature ranging was 30~40 ℃,two bacterial strains could keep most of its biogenic amines degrading activity. The biogenic amines degrading activity of Lactobacillus plantarum and Lactobacillus salivarius could be strongly inhibited when the concentration of NaCl and ethanol more than 8% and 4.5%,respectively. So,comparing with Lactobacillus plantarum,Lactobacillus salivarius emerged out to be more suitable for commercial starter cultures with lowered biogenic amines because of its better biodegradability.