Sensitivity of Bacillus coagulans spores to combinations of high hydrostatic pressure, heat, acidity and nisin

Effect of high pressure processing (HPP) on spore preparation of probiotic Bacillus coagulans LBSC [DSM 17654]

High pressure processing (HPP) has become a mainstream technology for modern age food processing. HPP conditions are detrimental to inherent microbial flora, including food pathogens. A probiotic intended for supplementation in a high-pressured processed food should therefore be stable to processing and subsequent storage conditions. The present study reports the viability of Bacillus coagulans LBSC [DSM 17654] spores at high hydrostatic pressures (HHP, 450 and 550 MPa) processing. B. coagulans LBSC spores were viable under both pressure condition at pH 2.60, 5.00, 7.00, and 8.25. Similar HPP conditions completely inactivated a reference strain Escherichia coli ATCC 25922. The HPP treated B. coagulans LBSC spore preparation showed no reduction in the viability on room temperature storage for a duration of six months. Results demonstrated the resilience of probiotic B. coagulans LBSC spores under HPP treatment, suggesting its potential incorporation in a range of functional foods and beverages.

A prospective, interventional, randomized, double-blind, placebo-controlled clinical study to evaluate the efficacy and safety of Bacillus coagulans LBSC in the treatment of acute diarrhea with abdominal discomfort

PURPOSE

Increasing resistance towards antibiotics has augmented the use of probiotics for the treatment of diarrhea and associated symptoms. Probiotics are active microorganisms which exert some health benefits when consumed in the right amount. This randomized, double-blind, placebo-controlled clinical trial was conducted on 60 "intention to treat" subjects to evaluate the safety and efficacy of probiotic preparation Lactic Acid Bacillus (LAB containing active ingredient Bacillus coagulans strain LBSC) for the treatment of acute diarrhea with abdominal discomfort.

METHODS

The Test-A arm (n = 30) was on B. coagulans LBSC [2 billion/g] and Placebo-B arm (n = 30) was on the carrier. The primary outcomes were the time to last unformed stool (TTLUS), number of unformed stools, change in severity of abdominal pain, time to complete resolution of abdominal discomfort, complete remission of diarrhea, and quality of life (QoL). The secondary outcomes were physical examination and vitals, hematological analysis, and assessment of reported adverse events (AEs) or serious adverse events (SAEs).

RESULTS

Trial data showed that the LAB was well-tolerated by participants at the dose provided. The LAB was effective in recovering from acute diarrhea with abdominal pain and discomforts and exhibited improved cluster of QoL. No AEs or SAEs were reported during the trial.

CONCLUSIONS

It is evident that the test drug, i.e., LAB (B. coagulans strain LBSC) is safe and effective for improving the pathophysiological conditions related to acute diarrhea and abdominal discomfort evaluated through stage-II clinical trial.

Inactivation of Bacillus anthracis Spores during Laboratory-Scale Composting of Feedlot Cattle Manure

Anthrax outbreaks in livestock have social, economic and health implications, altering farmer’s livelihoods, impacting trade and posing a zoonotic risk. Our study investigated the survival of Bacillus thuringiensis and B. anthracis spores sporulated at 15, 20, or 37°C, over 33 days of composting. Spores (∼7.5 log₁₀ CFU g^-1) were mixed with manure and composted in laboratory scale composters. After 15 days, the compost was mixed and returned to the composter for a second cycle. Temperatures peaked at 71°C on day 2 and remained ≥55°C for an average of 7 days in the first cycle, but did not exceed 55°C in the second. For B. thuringiensis, spores generated at 15 and 21°C exhibited reduced (P < 0.05) viability of 2.7 and 2.6 log₁₀ CFU g^-1 respectively, as compared to a 0.6 log₁₀ CFU g^-1 reduction for those generated at 37°C. For B. anthracis, sporulation temperature did not impact spore survival as there was a 2.5, 2.2, and 2.8 log₁₀ CFU g^-1 reduction after composting for spores generated at 15, 21, and 37°C, respectively. For both species, spore viability declined more rapidly (P < 0.05) in the first as compared to the second composting cycle. Our findings suggest that the duration of thermophilic exposure (≥55°C) is the main factor influencing survival of B. anthracis spores in compost. As sporulation temperature did not influence survival of B. anthracis, composting may lower the viability of spores associated with carcasses infected with B. anthracis over a range of sporulation temperatures.

In situ determination of Clostridium endospore membrane fluidity during pressure-assisted thermal processing in combination with nisin or reutericyclin

This study determined the membrane fluidity of clostridial endospores during treatment with heat and pressure with nisin or reutericyclin. Heating (90°C) reduced laurdan (6-dodecanoyl-2-dimethylaminonaphthalene) general polarization, corresponding to membrane fluidization. Pressure (200 MPa) stabilized membrane order. Reutericyclin and nisin exhibit divergent effects on heat- and pressure-induced spore inactivation and membrane fluidity.

Synergistic effect between different milk-derived peptides and proteins

Antimicrobial peptides derived from food proteins constitute a new field in the combined use of antimicrobial agents in food. The best examples of milk-derived peptides are those constituted by bovine lactoferricin [lactoferrin f(17-41)] (LFcin-B) and bovine alpha(s2)-casein f(183-207). The aim of this work was to study if the antimicrobial activity of a natural compound employed in food preservation, nisin, could be enhanced by combination with the aforementioned milk-derived peptides. Furthermore, the possibility of a synergistic effect between these peptides and bovine lactoferrin (LF) against Escherichia coli and Staphylococcus epidermidis was also studied. Finally, the most active combinations were assayed against the foodborne pathogens Listeria monocytogenes and Salmonella choleraesuis. Results showed a synergistic effect when LFcin-B was combined with bovine LF against E. coli. In the same way, the combination of LFcin-B with bovine LF was synergistic against Staph. epidermidis. Bovine LF and nisin increased their antimicrobial activity when they were assayed together with bovine alpha(s2)-casein f(183-207). It is important to note the synergistic effect among LFcin-B and bovine LF, because both compounds might be simultaneously in the suckling gastrointestinal tract and could, therefore, have a protective effect on it. The other synergistic effect high-lighted is that between alpha(s2)-casein f(183-207) and nisin against L. monocytogenes because of the ability of L. monocytogenes to develop resistance to nisin.