Fermented Antler Recovers Stamina, Muscle Strength and Muscle Mass in Middle-Aged Mice

In a previous study, we found that Lactobacillus curvatus HY7602-fermented antler (FA) improved exercise endurance by increasement of muscle mass and strength in a young mouse model. In this study, we investigated the effect of FA on recovery of muscle mass and strength in aging-induced muscle loss. We have used a middle-aged model in which muscle decline begins in many mammalian species. All mice performed treadmill exercise and forced swimming, and measured muscle grip strength. Then, calf muscle weight and histological analysis, blood biomarker and gene expression in soleus muscle tissue were measured. Muscle strength and forced swimming time were significantly increased in the FA-intake groups compared to controls. The levels of muscle and liver damage-related indicators (ATL, ALP, LDH and CK) and muscle endurance, fatigue and exercise performance-related indicators (lactate and creatinine) were significantly improved by FA supplementation. In addition, FA regulates genes related to muscle protein degradation (Atrogin-1 and MuRF1) and muscle fiber synthesis (MyoD and Myf5), resulting in increased muscle mass, and fiber diameter and area values. The Bax/Bcl-2 ratio, related to apoptosis in skeletal muscle was significantly decreased. These results demonstrate that FA improves exercise performance with ameliorating blood biomarkers and also increases muscle mass and muscle strength by inhibiting muscle proteolysis and promoting muscle synthesis in a middle-aged mouse.

Application of Liposome Encapsulating Lactobacillus curvatus Extract in Cosmetic Emulsion Lotion

Probiotic extracts have various positive attributes, such as antioxidant, tyrosinase inhibitory, and antimicrobial activity. Lactobacillus curvatus produces bacteriocin, which activates the lipid membrane structure and has potential as a natural preservative for cosmetic emulsions. In this study, L. curvatus extract was encapsulated in liposomes and formulated as an oil-in-water (O/W) emulsion. Radical scavenging activity, tyrosinase inhibition, and challenge tests were conducted to confirm the liposome activity and the activity of the applied lotion emulsion. The liposome-encapsulated extract had a relatively high absolute ζ-potential (52.53 > 35.43), indicating its stability, and 96% permeability, which indicates its potential as an active agent in lotion emulsions. Characterization of emulsions containing the liposomes also indicated a stable state. The liposome-encapsulated extract exhibited a higher radical scavenging activity than samples without the extract and non-encapsulated samples, and the functionality was preserved in the lotion emulsion. The tyrosinase inhibition activity of the lotion emulsion with the liposome-encapsulated extract was similar to that of the non-treated extract. Candida albicans and Aspergillus niger were also inhibited in the challenge test with the lotion emulsions during storage. Collectively, these findings indicate that the liposome-encapsulated extract and the lotion containing the encapsulated extract have potential applicability as natural preservatives.

Bacteriocin-mediated inhibition of some common pathogens by wild and mutant Lactobacillus species and in vitro amplification of bacteriocin encoding genes

Lactobacilli are the most common probiotics used in food and other industries because of their capability of producing bacteriocins. Bacteriocins are compounds that are used to kill pathogenic microorganisms. As most bacteria have become resistant to synthetic antibacterial tools, the importance of using probiotics as antibacterial agents has increased. This work was done to check the bacteriocin effect on some common pathogens and the influence of mutation on the bacteriocin activity of Lactobacilli was also investigated. Four strains were isolated, identified from meat and pickles samples via culturing methods, staining, biochemical tests, and ribotyping. Preliminary tests, including Gram staining and catalase test, were done for the confirmation of Lactobacillus species. All strains were gram-positive and catalase-negative. Antibacterial activity was checked against Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus thuringiensis, Escherichia coli, and Salmonella enteritis via agar well diffusion method. The mutations were done using ethidium bromide and the influence of wild and mutants were also checked. Interestingly, mutants developed more virulence than wild ones. It was also observed that they all were sensitive to pepsin. Protein estimation was done via Bradford method. Ribotyping of GCU-W-PS1 revealed 99 % homology with Lactobacillus plantarum and GCU-W-MS1 to Lactobacillus curvatus (99 % homology). Curvacin A, sakacin P, and plantaricin A genes were also amplified using specific primers. Gene sequence showed the presence of curvacin A gene in GCU-W-MS1. It was concluded that lactic acid bacteria could be used as antibacterial tools against common pathogens.

Probiotic-mediated p38 MAPK immune signaling prolongs the survival of Caenorhabditis elegans exposed to pathogenic bacteria

The host-microbiota cross-talk represents an important factor contributing to innate immune response and host resistance during infection. It has been shown that probiotic lactobacilli exhibit the ability to modulate innate immunity and enhance pathogen elimination. Here we showed that heat-inactivated probiotic strain Lactobacillus curvatus BGMK2-41 stimulates immune response and resistance of the Caenorhabditis elegans against Staphylococcus aureus and Pseudomonas aeruginosa. By employing qRT-PCR and western blot analysis we showed that heat-inactivated BGMK2-41 activated PMK-1/p38 MAPK immunity pathway which prolongs the survival of C. elegans exposed to pathogenic bacteria in nematode killing assays. The C. elegans pmk-1 mutant was used to demonstrate a mechanistic basis for the antimicrobial potential of BGMK2-41, showing that BGMK2-41 upregulated PMK-1/p38 MAPK dependent transcription of C-type lectins, lysozymes and tight junction protein CLC-1. Overall, this study suggests that PMK-1/p38 MAPK‐dependent immune regulation by BGMK2-41 is essential for probiotic-mediated C. elegans protection against gram-positive and gram-negative bacteria and could be further explored for development of probiotics with the potential to increase resistance of the host towards pathogens.

Antimicrobial Activity of Bacteriocin Produced By a New Lactobacillus Curvatus sp.LAB-3H Isolated From Traditional Yogurt

In recent years, the use of bacteriocin-producing Lactobacillus species has received much attention in different areas including using as probiotics, food preservation, and as broad antimicrobial spectrum activity. In this study, a bacteriocin-producing Lactobacillus strain was isolated from traditional yogurt. The isolate was identified by morphological, biochemical,16S rRNA analysis, and designated as Lactobacillus curvatus LAB-3H. The primary antimicrobial activity of the isolate was evaluated on Micrococcus luteus PTCC 1408 by the agar gel diffusion method. The growth of L. curvatus LAB-3H in MRS broth at 37°C and its antimicrobial activity against Lactobacillus casei ATCC 39392 was evaluated. In batch culture analysis, bacteriocin production starts at the early exponential growth phase and continues to the middle of the stationary phase about (660 AU/ml) at 28h and pH 3.8. Bacteriocin produced by L. curvatus LAB-3H showed antibacterial activity against some selected foodborne pathogens including; Listeria monocytogenes PTCC1294, Bacillus cereus PTCC1857, Staphylococcus aureus PTCC1917 and, Escherichia coli PTCC1276. For purification of bacteriocin, ammonium sulfate precipitation and cation exchange chromatography methods were used. The maximum antimicrobial activity observed was about 3985.15 AU/mg of protein, which was a 249.22-fold increase, and 5.21% yield compared with that in the cell-free supernatant. The molecular weight of bacteriocin was approximately 55 kDa by SDS-PAGE. The obtained results in this study demonstrate that bacteriocin from L. curvatus LAB-3H is a potential candidate for controlling microbial contaminations and can be used in different sectors such as food industries.

Isolation and identification of lactic acid bacteria from fermented meat products and evaluation of their antimicrobial effect

In this study, 30 lactic acid bacteria (LAB) were isolated from 20 different fermented meat products obtained from the Afyonkarahisar province (Turkey). Molecular identification of these isolates was performed by amplification of the 16S rDNA gene using the polymerase chain reaction (PCR) method. LAB isolated from 'sucuk' (spicy and fermented sausage) samples were identified as Enterococcus faecalis (2 isolates), Enterococcus durans (1 isolate), Lactobacillus sakei (3 isolates), Lactobacillus curvatus (2 isolates), Weissella viridescens (3 isolates), Weissella cibaria (2 isolates) and Weissella hellenica (1 isolate). LAB, isolated from salami samples, were identified as W. viridescens (1 isolate), E. durans (3 isolates), Leuconostoc mesenteroides (4 isolates), Carnobacterium maltaromaticum (1 isolate), Macrococcus caseolyticus (1 isolate). Also, LAB, isolated from sausages samples, were identified as E. faecalis (1 isolate), E. durans (4 isolates), Lactobacillus plantarum (1 isolate). Both agar spot and agar well diffusion assay methods were used to determine the antimicrobial activity of the LAB isolates. Isolates of LAB showed higher antimicrobial activity against Listeria monocytogenes ATCC 19115, Staphylococcus aureus ATCC 25923, Klebsiella pneumoniae NRRL B 4420, Pseudomonas aeruginosa ATCC 11778, Streptococcus faecalis NRRL B 14617 than against Escherichia coli ATCC 35218 and Bacillus subtilis NRS 744. Results showed that the LAB isolates produced antimicrobial substances that have a potential for different industrial and biotechnological uses.

Fermentative losses and chemical composition and in vitro digestibility of corn grain silage rehydrated with water or acid whey combined with bacterial-enzymatic inoculant

This study aimed to evaluate the effects of rehydration with water or acid whey, as well as the effects of bacterial-enzymatic inoculant on fermentation losses, aerobic stability, and chemical composition and in vitro digestibility of corn grain silages. The treatments consisted of corn kernels (Zea mays) ground through a 3-mm sieve and rehydrated with chlorine-free water or unsalted whey (NaCl) combined or not with bacterial-enzymatic inoculant. This was a 2 x 2 factorial completely randomized design with sources of rehydration (water or whey) and absence and presence of bacterial-enzymatic inoculant with eight replications. Water and acid whey were added to ground corn with 12% moisture in order to increase it to 35%. Rehydrated corn was ensiled in Polyvinyl chloride (PVC) minisilos and stored for 60 d. The bacterial-enzymatic inoculant used was composed of Lactobacillus curvatus, L. acidophilus, L. plantarum, L. buchneri, L. lactis, Pediococcus acidilactici, Propionibacterium acidipropionici and Enterococcus faecium, in concentrations of 1010 CFU g-1 and 5% cellulose-based enzyme complex. The aerobic exposure of silages was evaluated for 120 hours. There was interaction (P = 0.02) between the sources of rehydration and the use or not of the inoculant on the values of silage temperature during aerobic exposure. There was a difference for dry matter (DM) losses (P=0.38) between rehydrated corn silages with and without inoculant. DM losses were 37.51% higher in silage without inoculant compared to silage with inoculant (3.84% DM). There was no difference between the sources of rehydration on DM losses (P = 0.39), with a mean value of 4.99%. Corn rehydration using acid whey (P < 0.01) increased 2.19% and 31.36% DM and ash content compared to water, an average of 66.14% and 1.28%, respectively. There was no interaction (P = 0.30) between the sources of rehydration and the use of inoculants on the in vitro digestibility of DM (mean of 79.26%). The use of the bacterial-enzymatic inoculant improved the fermentation characteristics, aerobic stability and nutritional value of corn grain silage rehydrated with water or whey.