Exopolysaccharides of Lactic Acid Bacteria: Production, Purification and Health Benefits towards Functional Food

Abstract

Lactic acid bacteria (LAB) are capable of synthesising metabolites known as exopolysaccharides (EPS) during fermentation. Traditionally, EPS plays an important role in fermented dairy products through their gelling and thickening properties, but they can also be beneficial to human health. This bioactivity has gained attention in applications for functional foods, which leads them to have prebiotic, immunomodulatory, antioxidant, anti-tumour, cholesterol-lowering and anti-obesity activity. Understanding the parameters and conditions is crucial to optimising the EPS yields from LAB for applications in the food industry. This review provides an overview of the functional food market together with the biosynthesis of EPS. Factors influencing the production of EPS as well as methods for isolation, characterisation and quantification are reviewed. Finally, the health benefits associated with EPS are discussed.

Laktik Asit Bakterileri Tarafından Üretilen Ekzopolisakkaritler ve Terapötik Etkileri

“…Lactococcus, Leuconostoc ve Weissella cinslerinin EPS üreticisi oldukları bilinmektedir [3,18]. LAB'ler tarafından üretilen EPS'ler, hücreyi ozmotik stres, düşük su aktivitesi, fagositoz, bakteriyofajlar, toksik bileşikler ve makrofajlara karşı koruyucu işlevlere sahiptir [8]. Diğer yandan, EPS'ler hücre tanımada, yüzeylere tutunma ve probiyotikler gibi mikrobiyal ekosistemlerin bağırsak florasında kolonizasyonunu kolaylaştıran biyofilmlerin oluşmasında kilit öneme sahiptir.…”

“…EPS'lerin birçoğu uzun karbohidrat zincirlerinden oluştuğundan kısa zincirlere kıyasla daha yavaş metabolize edilerek, kolon bölgelerinde daha uzun süre kalmaktadır. Kolondaki bir ya da sınırlı sayıdaki bakterinin büyüme ve gelişmesini sağlayarak prebiyotik olarak fonksiyon gösterdiği ve bağırsak mikrobiyotasını modifiye ederek sağlığı olumlu yönde etkilediği bilinmektedir [6,8].…”

Probiotic Properties of Exopolysaccharide-Producing Bacteria from Natto

“…They contain several kinds of useful probiotics which can stimulate the immune system and inhibit the growth of pathogen [ 11 ]. Moreover, some probiotics may secrete the EPS [ 12 ].…”

Improvement of the Lyophilization Survival Rate of Lactobacillus casei via Regulation of Its Surface Substances

“…Numerous studies have shown that surface substances produced by lactobacilli are functional substances that afford protection from harsh environments [ 8 ]. Exopolysaccharides could improve resistance to dry environments and phagocytosis by other cells [ 9 ], resistance to antibiotics, osmotic pressure, resistance to phage attack [ 10 ], and the freeze-dried survival rate [ 11 ]. Dimopoulou et al found that the survival rate of Oenococcus oeni -producing CPSs is significantly higher than that of Oenococcus oeni -not producing CPSs, which indicated that the CPSs produced by Oenococcus oeni could protect the cell structure in cooperation with maltodextrin or sucrose, thereby improving the freeze-drying survival rate [ 12 ].…”