Iorizzo Massimo, Lombardi Silvia Jane, Macciola Vincenzo, Testa Bruno, Lustrato Giuseppe, Lopez Francesco, De Leonardis Antonella
Department of Agriculture, Environmental and Food Sciences (DiAAA), University of Molise, Via De Sanctis, 86100 Campobasso, Italy.
Department of Biosciences and Territory (DiBT), University of Molise, Contrada Lappone, Pesche, 86090 Isernia, Italy.
ScientificWorldJournal. 2016;2016:1917592. doi: 10.1155/2016/1917592. Epub 2016 Jun 30.
Technological properties of two strains of Lactobacillus plantarum (B3 and B11) and one of Lactobacillus pentosus (B4), previously isolated from natural fermented green olives, have been studied in vitro. Acidifying ability, salt, temperature, and pH tolerances of all strains were found in the range reported for similar strains produced in Italy and optimal growth conditions were found to be 6.0-8.0 pH, 15-30°C temperature, and less than 6% NaCl. Moreover, all strains showed very good tolerance to common olive phenol content (0.3% total phenol) and high oleuropein-degrading capability. It was found that medium composition affected the bacterial oleuropein degradation. B11 strain grown in a nutrient-rich medium showed a lower oleuropein-degrading action than when it was cultivated in nutrient-poor medium. Furthermore, enzymatic activity assays revealed that oleuropein depletion did not correspond to an increase of hydroxytyrosol, evidencing that bacterial strains could efficiently degrade oleuropein via a mechanism different from hydrolysis.
对先前从天然发酵绿橄榄中分离出的两株植物乳杆菌（B3和B11）和一株戊糖乳杆菌（B4）的技术特性进行了体外研究。发现所有菌株的酸化能力、耐盐性、温度耐受性和pH耐受性均在意大利生产的类似菌株所报告的范围内，最佳生长条件为pH 6.0 - 8.0、温度15 - 30°C和NaCl含量低于6%。此外，所有菌株对常见橄榄酚含量（总酚0.3%）表现出非常好的耐受性，并且具有高橄榄苦苷降解能力。发现培养基组成会影响细菌对橄榄苦苷的降解。在营养丰富的培养基中生长的B11菌株比在营养贫乏的培养基中培养时表现出更低的橄榄苦苷降解作用。此外，酶活性测定表明，橄榄苦苷的消耗与羟基酪醇的增加并不对应，这表明细菌菌株可以通过不同于水解的机制有效降解橄榄苦苷。
