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[Display omitted] • The EPS production from Enterococcus faecium MC-5 was optimized through RSM and purified. • This is the first report of levan production by E. faecium species, which is a fructan-homopolysaccharide. • The EPS was found to be a low molecular weight levan of 24 kDa. • The EPS exhibited excellent in-vitro antioxidant and antibiofilm activity. In the present study, Enterococcus faecium MC-5 isolated from the fish gut was cultured in the MRS broth to produce exopolysaccharide (EPS). The maximum EPS production was optimized using Response Surface Methodology (RSM) with three different factors which include sucrose, ammonium nitrate and pH. RSM result predicted that maximum EPS (16.48 g/L) production could be attained by supplementing 30 g/L sucrose and 15 g/L ammonium nitrate in the MRS broth with the initial pH of 6.407. The EPS produced was subjected to purification by column chromatography techniques. Monosaccharide analysis by HPLC confirmed the presence of fructose monomer. The purified EPS MC-5 showed a molecular weight of 24 kDa. The purified EPS was further characterized by FT-IR and NMR which confirmed the presence of β-(2,6) fructofuranoside units and suggested that the EPS MC-5 is a levan-type polysaccharide. Congo red analysis suggested that the EPS MC-5 possesses a triple-helix structure whereas the SEM images showed that the EPS has a porous and globular structure. The EPS was found to be semi-crystalline through XRD analysis. Thermogravimetric analysis showed EPS MC-5 possesses higher thermal stability having a degradation temperature of 338.13 °C. The EPS MC-5 exhibited excellent antioxidant activities and showed promising antibiofilm activity against Listeria monocytogenes , Salmonella enterica , Salmonella typhi and Vibrio anguillarum. The present study is the first report of levan-type EPS production by Enterococcus faecium sp., which has been characterized for its physicochemical and biological properties. These properties associated with EPS MC-5 suggested that it can serve as a potential ingredient or supplement in the food system with significant health benefits. [ABSTRACT FROM AUTHOR]

The goal of this study was to determine the unique characteristics of Enterococcus faecium MC-5, a probiotic bacteria isolated from the intestine of a fish, Cyprinus carpio specularis , collected from Dal Lake in Srinagar, Kashmir, India. For this, the important valuable probiotic attributes, some functional properties, and safety assessments were analyzed in-vitro for the strain MC-5. The strain E. faecium MC-5 exhibited high resistance to low pH, high bile salt, lysozyme, and phenol. The strain MC-5 showed excellent auto- and co-aggregation properties and displayed remarkable hydrophobicity towards various tested hydrocarbons which suggested that the strain possesses venerable adhesion properties. Apart from these, the cell-free supernatant (CFS) of strain MC-5 exhibited phenomenal antimicrobial activity against the tested pathogens. A scanning electron microscope (SEM) image revealed strain MC-5 finely adhered to human colon adenocarcinoma cells (HCT-15 cells). The strain MC-5 showed high bile salt hydrolase activity and excellent cholesterol removal ability of 70.27%. The intact cells of strain MC-5 also showed strong DPPH scavenging activity. The EPS produced by E. faecium MC-5 inhibited the adhesion of Listeria monocytogenes, Staphylococcus aureus, and Salmonella enterica on HCT-15 cells with maximum inhibition rates of 41.82, 40.34, and 55.51%, respectively for displacement assay, which was higher as compared to exclusion (26.06, 26.11, and 39.23%) and competition assays (30.06, 26.7, and 41.20%). Strain MC-5 did not exhibit hemolysis and was also found susceptible to vancomycin and other clinically important antibiotics. When evaluating all the results from the present study, it is propounded that strain MC-5 has enviable probiotic characteristics and thus can be used as bio-protective cultures and/or bio-shield in food and pharmaceutical industries. • Enterococcus faecium MC-5 was isolated from the intestine of a fish, Cyprinus carpio specularis. • The strain E. faecium MC-5 exhibited high resistance to low pH, high bile salt, lysozyme, and phenol. • SEM image revealed that strain MC-5 finely adhered to human colon adenocarcinoma cells (HCT-15 cells). • The strain MC-5 showed high bile salt hydrolase activity and excellent cholesterol removal ability of 70.27%. • Strain MC-5 did not exhibit hemolysis and was also found susceptible to vancomycin and other relevant antibiotics. [ABSTRACT FROM AUTHOR]

A low molecular weight polysaccharide, the AMLP was isolated from the leaves of Avicennia marina and sequentially purified using DEAE-Sepharose fast flow and size exclusion chromatography. Monosaccharide analysis suggested that AMLP is mainly composed of fucose (38.34 %), galactose (30.16 %), mannose (13.32 %), and rhamnose (18.18 %). IR spectroscopy and High-performance size-exclusion chromatography (HPSEC) analysis revealed that AMLP was a sulfated homogenous heteropolysaccharide, and their molecular weight observed was 1.31 kDa. The Spectroscopic analysis of AMLP comprised of (1,2)- α-L-Fuc p , (1,6)-β-D-linked galactan, α-rhamnose, and (1,4)-β-D mannose residues. AMLP has a loosely arranged granular bead-like appearance present on the surface and also with the presence of some porous structures. The rheological properties of AMLP exhibited pseudoplastic properties with shear-thinning flow behavior. Congo red test and X-ray diffraction (XRD) results indicated the semi-crystalline nature of AMLP with a triple-helical structure. Thermogravimetric and Differential scanning calorimetry (TGA-DSC) analysis of AMLP found was thermally stable and its degradation temperature observed was 280 °C. Furthermore, AMLP exhibited potential antibacterial and antibiofilm properties against bacterial pathogens such as Listeria monocytogenes, Escherichia coli , Klebsiella pneumonia , Salmonella typhimurium, and Staphylococcus aureus. The In vitro antioxidant activities such as DPPH scavenging, Superoxide radical scavenging, OH radical scavenging, and reducing power activities of AMLP were evaluated and the results revealed that the tested antioxidant activities of AMLP were significantly (P < 0.05) increased with increasing the concentrations. Overall, these findings suggested that AMLP could be used as a potential candidate in pharmaceutical, cosmetics, and food industry applications. [Display omitted] • AMLP (polysaccharide) from the leaves of Avicennia marina mangrove plant was characterized. • The backbone of AMLP contains (1,2)-α-L-Fuc p , (1,6)-β-D-linked galactan, α-rhamnose and (1,4)-β-D mannose residues. • It shows pseudoplastic flow properties with shear thinning behavior in solution. • AMLP showed triple-helix conformation and high thermal stability with degradation temperature of 280 °C. • It showed promising antioxidant activity and antibiofilm activity against several pathogens. [ABSTRACT FROM AUTHOR]

In the present work, a probiotic bacteria Weissella cibaria MD2 was used for the production of exopolysaccharide (EPS), which was characterized and evaluated for several technological and biological activities. The RSM assisted optimization resulted in maximum production of EPS (12.58 g/L) when the MRS broth was supplemented with optimal carbon and nitrogen source. The EPS produced was purified using chromatography techniques and the monosaccharide analysis by HPLC showed that it was a fructan EPS. The NMR analysis suggested that the EPS MD2 is an inulin-type linear polysaccharide that consists of β (1 → 2) linkage. The scanning electron microscopy (SEM) images revealed that EPS MD2 has a thin sheet-like appearance with fewer fibers-like structures. The results from the thermal analysis showed that the EPS MD2 was highly thermostable and possess a degradation temperature of 279.90 °C. The x-ray diffraction pattern showed that the powdered EPS MD2 has a semi-crystalline nature. The EPS MD2 showed excellent antioxidant activities to scavenge free radicals. The fructan EPS showed a promising effect in increasing oxidative stress tolerance and enhancing the lifespan of C. elegans by activating the nuclear localization of DAF-16. The incredible physico-chemical and antioxidant properties (in vitro and in vivo) of this EPS can be implemented in the pharmaceutical and food industry. • The EPS produced from Weissella cibaria MD2 was optimized, purified and characterized. • The EPS MD2 was found to be of low molecular weight inulin-type fructan (3.23 kDa). • This is the first report of the production of inulin-type fructan EPS by W. cibaria to be characterized. • The fructan EPS was highly thermostable and showed a degradation temperature of 279.90 °C. • Fructan EPS exhibit excellent antioxidant property in vitro and in vivo. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the probiotic potential of Weissella confusa MD1 and Weissella cibaria MD2 isolated from a fermented batter. They possessed characters like high survivability in gastrointestinal conditions, tolerance towards lysozyme and phenol. Both strains exhibited strong auto-aggregation property and co-aggregation with Listeria monocytogenes. The adhesion behavior towards intestinal epithelial cells (HT-29 cells) was observed by scanning electron microscopy (SEM). Both strains MD1 and MD2 exhibited antimicrobial activity against foodborne pathogens like Escherichia coli , Salmonella enterica , Listeria monocytogenes , Salmonella typhi and Staphyloccocus aureus. They also showed high bile salt hydrolase activity towards sodium taurocholate and bile salt mixture. Strain MD1 and MD2 demonstrated a tremendous reduction in the cholesterol by 67.11% and 78%, respectively. The intact cells of both strains showed strong antioxidant activity by scavenging 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical and inhibition of linoleic acid peroxidation. The formation of biofilm was demonstrated by using atomic force microscopy (AFM) on the glass cover. Both strains showed sensitivity towards conventionally used antibiotics and no hemolytic activity. The results from the study suggested that Weissella confusa MD1 and Weissella cibaria MD2 have exemplary technological properties that can be implemented in the pharmaceutical and food industry. • Probiotic properties of W. confusa MD1 and W. cibaria MD2 were evaluated. • SEM images revealed phenomenal adhesion behavior towards HT-29 cells. • Both strains showed antimicrobial activity against foodborne pathogens. • Intact cells of both strains possess high antioxidant property. • Both strains were regarded safe after safety evaluation. [ABSTRACT FROM AUTHOR]

Rhizophora mucronata Leaves Polysaccharide (RMLP) was extracted and purified from the mangrove Rhizophora mucronata leaves by anion-exchange and size-exclusion column chromatography. Physicochemical characterization of RMLP was evaluated by spectrtoscopic analysis (FT-IR, 1H & 13C NMR) and RP-HPLC. The molecular weight of RMLP was found to be 2.69 kDa, comprised of monosaccharides such as arabinose, galacturonic acid, galactose, mannose, xylose, rhamnose and glucose. The scanning electron microscope (SEM) images showed the appearance of irregular stacks of crystal blocks with a compact structure of RMLP at 5000x fold magnification. The viscosity analysis revealed the pseudoplastic fluid behavior of the polysaccharide with shear-thinning properties. The result of x-ray diffraction (XRD) and Congo red analysis confirmed the semicrystalline nature of RMLP and has triple-helical conformation. Thermal analysis (TGA and DSC) results proved high thermal stability of the RMLP fraction as its degradation temperature was found to be 310 C. The RMLP showed tremendous antibiofilm activity in a dose-dependent manner against the gram positive and gram negative pathogens. The RMLP showed effective antioxidant ability on DPPH scavenging, superoxide, ABTS, hydroxyl anion radical and Fe2+ chelating activities. These findings indicated that RMLP has promising antioxidant and antibiofilm properties against human pathogens, which makes it a better therapeutic agent in the field of functional foods and medicines. [Display omitted] • RMLP (polysaccharide) from the leaves of Rhizophora mucronata mangrove plant was characterized. • RMLP consists of arabinose, galacturonic acid, and galactose monosaccharides in major amount. • It showed shear thinning behavior in the solution having triple-helix conformation. • RMLP showed semi-crystalline nature and high thermal stability with a degradation temperature of 310 °C. • It shows promising antioxidant activity and antibiofilm activity against tested pathogens. [ABSTRACT FROM AUTHOR]