Biopolymers from lactic acid bacteria. Novel applications in foods and beverages

Abstract

Lactic acid bacteria (LAB) are microorganisms widely used in the fermented food industry worldwide. Certain LAB are able to produce exopolysaccharides (EPS) either attached to the cell wall (capsular EPS) or released to the extracellular environment (EPS). According to their composition, LAB may synthesize heteropolysaccharides or homopolysaccharides. A wide diversity of EPS are produced by LAB concerning their monomer composition, molecular mass, and structure. Although EPS-producing LAB strains have been traditionally applied in the manufacture of dairy products such as fermented milks and yogurts, their use in the elaboration of low-fat cheeses, diverse type of sourdough breads, and certain beverages are some of the novel applications of these polymers. This work aims to collect the most relevant issues of the former reviews concerning the monomer composition, structure, and yields and biosynthetic enzymes of EPS from LAB; to describe the recently characterized EPS and to present the application of both EPS-producing strains and their polymers in the fermented (specifically beverages and cereal-based) food industry.

Exopolysaccharides Production by Lactic Acid Bacteria

“…Molecular mass of HePS ranges from 10 4 to 10 6 Da, which is generally lower than the average molecular mass of HoPS (up to approximately 10 7 Da) [16]. As it is seen, the HePS production levels from LAB are generally lower than those for HoPS [17,18]. Also, producer microorganisms don't use the bacterial EPSs as energy sources [19].…”

“…Some of characteristics of HoPS have been described such as the isolation of HoPS-producing strains, the molecular and structural characterization of these EPS, studies on their biosynthetic enzymes, and the HoPS application in food. Weissella genera are mainly produced HoPS [18]. The HoPS consist of one type of monosaccharide ( Figure 1).…”

Exopolysaccharides produced by lactic acid bacteria: from health-promoting benefits to stress tolerance mechanisms

“…The molecular mass is generally between 10 4 and 10 6 Da (Ryan et al 2015). The exopolysaccharides yield and composition produced by some LAB appear to be significantly influenced by culture and fermentation conditions (i.e., pH, temperature, incubation time, and medium composition) (Dueñas et al 2003;Torino et al 2015;Zannini et al 2016) while in some strains appear a relatively constant production of these polymers under a variety of conditions (Boels et al 2003). To date, among LAB, the yield of heteropolysaccharides is quite variable (Tsuda 2013); one of the largest EPS producers is L. rhamnosus RW-9595M (2775 mg/L) (Macedo et al 2002) and Lactobacillus kefiranofaciens WT-2B (2500 mg/L) (Maeda et al 2004a) followed by L. lactis subsp.…”

Isolation and Characterization of Larvicidal Extracellular Polysaccharide (EPS) from Pseudomonas aeruginosa B01

“…The linkage pattern of the monomer is evaluated by methylation of all free hydroxyl groups. The combination of EPS from P. aeruginosa and P. fluorescens was studied by various research groups (Tian, 2008;Torino et al, 2015). (Andersson et al, 2009).…”