Optimization, Probiotic Characteristics, and Rheological Properties of Exopolysaccharides from Lactiplantibacillus plantarum MC5

Abstract

This study optimized the exopolysaccharides (EPS) production for Lactiplantibacillus plantarum MC5 (Lp. plantarum MC5) and evaluated the resistance to human simulated digestive juices, antioxidant activity in vitro, and rheological properties of EPS-MC5. The results showed that maximum EPS production of 345.98 mg/L (about 1.5-old greater than the initial production) was obtained at optimal conditions of inoculum size (4.0%), incubation time (30 h), incubation temperature (34.0 °C), and initial pH value (6.40). Furthermore, the resisting-digestion capacity of EPS-MC5 after 180 min in α-amylase, simulated gastric juice (pH 2.0, 3.0, 4.0), and simulated intestinal juice (pH 6.8) was 98.59%, 98.62%, 98.78%, 98.86%, and 98.74%, respectively. In addition, the radical scavenging rates of DPPH•, ABTS•, •OH, and ferric-iron reducing power (OD700) of EPS-MC5 were 73.33%, 87.74%, 46.07%, and 1.20, respectively. Furthermore, rheological results showed that the EPS-MC5 had a higher apparent viscosity (3.01 Pa) and shear stress (41.78 Pa), and the viscoelastic modulus (84.02 and 161.02 Pa at the shear frequency of 100 Hz). These results provide a new insight into the application of EPS in human health and functional foods, which could also improve theoretical guidance for the industrial application of EPS.

Functional features of the exopolysaccharide extracts produced by Lactiplantibacillus strains isolated from table olives

“…There is plenty of well-described evidence of the antioxidant activity of EPSs synthesised by Lactobacillus species, such as the EPSs produced by L. helveticus MB2–1, L. acidophilus P185, L. plantarum S123, L. plantarum RO30, L. plantarum MC5, L. casei NA-2, and L. pentosus . 23–29 Data obtained in this work showed the great antioxidant activity of many of the EPS crude extracts obtained from Lactiplantibacillus strains, especially LPG1.…”

“…In a recent study by Zhao & Liang (2023), RSM was employed to identify the optimal conditions for L. plantarum MC5 EPS production considering various environmental variables. 27 They achieved a maximum EPS production of 345.98 mg L −1 at an inoculum size of 4.0%, an incubation…”

“…In a recent study by Zhao & Liang (2023), RSM was employed to identify the optimal conditions for L. plantarum MC5 EPS production considering various environmental variables. 27 They achieved a maximum EPS production of 345.98 mg L −1 at an inoculum size of 4.0%, an incubation time of 30 h, an initial pH of 6.4, and a temperature of 34 Sánchez et al (2006) reported EPS production of 514 mg L −1 by L. pentosus LPS26, isolated from table olives. 8 This high production was observed at pH 6.0, a suboptimal growth temperature of 20 °C, and a glucose concentration of 30 g L −1 in the medium.…”

Whole genome sequence of Lactiplantibacillus plantarum MC5 and comparative analysis of eps gene clusters

“…plantarum JCM 1149 (92%), so strain MC5 was identified as Lp. plantarum ( Figure 2C , Zhao and Liang, 2023 ). The NR (non-redundant) database excludes the most significant sources of redundant sequences (EST, STS, GSS, HTGS) and contains protein sequences translated from DNA sequences preserved throughout NCBI GenBank; making the information in this database is very comprehensive.…”

“…plantarum JCM 1149 (92%), so strain MC5 was identified as Lp. plantarum (Figure 2C, Zhao and Liang, 2023).…”