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The food industry has been developing new products with health benefits, extended shelf life, and without chemical preservation. Bacteriocin-producing lactic acid bacteria (LAB) strains have been evaluated for food fermentation to prevent contamination and increase shelf life. In this study, potentially probiotic LAB strains, Lactiplantibacillus (Lb.) plantarum ST8Sh, Lacticaseibacillus (Lb.) casei SJRP38, and commercial starter Streptococcus (St.) thermophilus ST080, were evaluated for their production of antimicrobial compounds, lactic acid and enzyme production, carbohydrate assimilation, and susceptibility to antibiotics. The characterization of antimicrobial compounds, the proteolytic activity, and its inhibitory property against Listeria (List.) monocytogenes and Staphylococcus (Staph.) spp. was evaluated in buriti and passion fruit-supplemented fermented milk formulations (FMF) produced with LAB strains. Lb. plantarum ST8Sh was found to inhibit List. monocytogenes through bacteriocin production and produced both L(+) and D(−) lactic acid isomers, while Lb. casei SJRP38 mainly produced L(+) lactic acid. The carbohydrate assimilation profiles were compatible with those usually found in LAB. The potentially probiotic strains were susceptible to streptomycin and tobramycin, while Lb. plantarum ST8Sh was also susceptible to ciprofloxacin. All FMF produced high amounts of L(+) lactic acid and the viability of total lactobacilli remained higher than 8.5 log CFU/mL during monitored storage period. Staph. aureus ATCC 43300 in fermented milk with passion fruit pulp (FMFP) and fermented milk with buriti pulp (FMB), and Staph. epidermidis KACC 13234 in all formulations were completely inhibited after 14 days of storage. The combination of Lb. plantarum ST8Sh and Lb. casei SJRP38 and fruit pulps can provide increased safety and shelf-life for fermented products, and natural food preservation meets the trends of the food market. [ABSTRACT FROM AUTHOR]

Fruit by-products, due to their unique chemical composition containing dietary fibers and bioactive compounds, may favor the growth of probiotic strains. This study evaluated the fermentation of araticum, baru, and pequi by-products using Lactobacillus acidophilus (La-5, LA3, and NCFM) and Bifidobacterium animalis subsp. lactis (Bb-12) probiotic strains. We assessed probiotic viability, short-chain fatty acid levels, and bioactive compound levels after 48 h of fermentation. Araticum and pequi by-products led to counts higher than 6 log CFU/mL after 48-h fermentation for all Lactobacillus strains, but only the araticum by-product supported the growth of the Bb-12 strain. Fermentation of araticum by-product resulted in greater amounts of acetate (39.97 mM for LA3 and 39.08 mM for NCFM) and propionate (0.20 mM for NCFM), while baru by-product showed greater amounts of butyrate (0.20 mM for La-5 and Bb-12). Fermentation of araticum and baru by-products resulted in an increase in bioactive compounds, with the latter showing total phenolic compounds and antioxidant activity from 1.4 to 1.7 and from 1.3 to 3.1 times higher, respectively, than the negative control treatment. Araticum by-product exhibited a higher potential for prebiotic effects, and fermentation by the tested probiotic strains is essential to increase bioactive compound levels. [ABSTRACT FROM AUTHOR]

The effect of putative probiotic fermented milk (FM) with buriti pulp (FMB) or passion fruit pulp (FMPF) or without fruit pulp (FMC) on the microbiota of healthy humans was evaluated. FM formulations were administered into a simulator of the human intestinal microbial ecosystem (SHIME®) to evaluate the viability of lactic acid bacteria (LAB), microbiota composition, presence of short-chain fatty acids (SCFA), and ammonium ions. The probiotic LAB viability in FM was affected by the addition of the fruit pulp. Phocaeicola was dominant in the FMPF and FMB samples; Bifidobacterium was related to FM formulations, while Alistipes was associated with FMPF and FMB, and Lactobacillus and Lacticaseibacillus were predominant in FMC. Trabulsiella was the central element in the FMC, while Mediterraneibacter was the central one in the FMPF and FMB networks. The FM formulations increased the acetic acid, and a remarkably high amount of propionic and butyric acids were detected in the FMB treatment. All FM formulations decreased the ammonium ions compared to the control; FMPF samples stood out for having lower amounts of ammonia. The probiotic FM with fruit pulp boosted the beneficial effects on the intestinal microbiota of healthy humans in addition to increasing SCFA in SHIME® and decreasing ammonium ions, which could be related to the presence of bioactive compounds. [ABSTRACT FROM AUTHOR]

Obesity is currently considered a global epidemic and it leads to several alterations on the human body and its metabolism. There are evidences showing that the intestinal microbiota can influence on the pathogenesis of obesity. Microbiota plays a vital role not only in the digestion and absorption of nutrients, but also in the homeostatic maintenance of host immunity, metabolism, and gut barrier. Its dietary alteration is an important target in the treatment of obesity. Emerging evidence suggests that modifying the composition of the gut microbiota through probiotic, prebiotic, and synbiotic supplementation may be a viable adjuvant treatment option for obese individuals. In this review, the impact of probiotics, prebiotics, and synbiotics on the anthropometric profile, biochemical regulation, clinical, and immunological markers, as well as on the gut microbiota of obese hosts is described. It also emphasizes how changes in the composition and/or metabolic activity of the gut microbiota through the administration of nutrients with probiotic, prebiotic, or synbiotic properties can modulate the host's gene expression and metabolism, and thereby positively influence on the host's adipose tissue development and related metabolic disorders. The beneficial effects on the host's metabolism promoted by prebiotics, probiotics, and synbiotics have been successfully demonstrated by several studies. However, further investigation is needed to fully explain the cellular mechanisms of action of probiotics and prebiotics on human health, and also to elucidate the relationship between microbiota and obesity etiology, using well-designed, long-term, and large-scale clinical interventions. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the probiotic properties of Lactobacillus casei and Lactobacillus fermentum strains, as well as to select novel and safe strains for future development of functional fermented products. The in vitro auto-aggregation, co-aggregation, hydrophobicity, β-galactosidase production, survival to gastrointestinal tract (GIT), and antibiotic susceptibility were evaluated. The selected strains were additionally tested by the presence of genes encoding adhesion, aggregation and colonization, virulence factors, antibiotic resistance, and biogenic amine production, followed by the evaluation of acidifying kinetic parameters in milk, and survival of the strains under simulated GIT conditions during refrigerated storage of fermented milk. Most strains of both species showed high auto-aggregation; some strains showed co-aggregation ability with other lactic acid bacteria (LAB) and/or pathogens, and both species showed low hydrophobicity values. Seven L. casei and six L. fermentum strains produced β-galactosidase enzymes, and ten strains survived well the simulation of the GIT stressful conditions evaluated in vitro. All strains were resistant to vancomycin, and almost all the strains were resistant to kanamycin. L. casei SJRP38 and L. fermentum SJRP43 were distinguished among the other LAB strains by their higher probiotic potential. L. fermentum SJRP43 presented fewer genes related to virulence factors and antibiotic resistance and needed more time to reach the maximum acidification rate (Vmax). The other kinetic parameters were similar. Both strains survived well (> 8 log10 CFU/mL) to the GIT-simulated conditions when incorporated in fermented milk. Therefore, these strains presented promising properties for further applications in fermented functional products. [ABSTRACT FROM AUTHOR]

The aims of this research were to evaluate the safety and probiotic potential of Enterococcus spp. strains and select novel strains for future development of new functional fermented products. Bile salt hydrolase (BSH) activity, capacity of auto-aggregation and co-aggregation, hydrophobicity, tolerance to different pH values and NaCl content, mucin degradation, and antibiotic susceptibility were evaluated. Considering the preliminary probiotic features and safety, the strains were selected for complementary tests: tolerance to gastrointestinal tract (GIT) conditions, adhesion to Caco-2 cells and β-galactosidase activity, and presence of genes encoding virulence factors, antibiotic resistance, and biogenic amines were also performed for the selected strains. Enterococcus faecium SJRP20 and SJRP65 resisted well to the GIT conditions, presented low adhesion property, produced β-galactosidase although they did not present genes implicated in adhesion, aggregation, and colonization. Enterococcus faecium SJRP65 showed fewer genes related to antibiotic resistance and virulence factors and presented good functional properties, with interesting features for future application in dairy products. [ABSTRACT FROM AUTHOR]

ABSTRACT This study examined the antioxidant activity of lyophilized rosemary extract added to soybean oil, subjected to thermoxidation conditions and also its synergistic effect with the synthetic antioxidant tertiary butylhydroquinone (TBHQ). Soybean oil samples with no antioxidant added (SO), 3,000 mg/kg rosemary extract (RE), 50 mg/kg TBHQ (TBHQ), and a mixture of those two antioxidants (RE + TBHQ) were heated to 180C for 20 h. After 0, 10 and 20 h, the oxidative stability, total polar compounds, tocopherol content and fatty acid profile were determined. The addition of rosemary extract increased oxidative stability and resulted in a lower formation of total polar compounds and a higher retention of tocopherols. The RE treatment showed the highest amount of polyunsaturated fatty acids after 20 h. There was not any synergy between TBHQ and rosemary extract in preventing oxidation of soybean oil. Rosemary extract showed a higher antioxidant potential when compared with TBHQ. PRACTICAL APPLICATIONS Antioxidants are important ingredients in food processing because they have the capacity to protect foods, containing oils and fats, from damage caused by free radicals and reactive oxygen species. Synthetic antioxidants are widely used in the food industry; however, their utilization has been questioned because of toxicity. Therefore, there is a growing interest in the use of natural antioxidants to reduce or replace the synthetic antioxidants. Several species are used in cooking, medicine and by the pharmaceutical industry, standing out the rosemary. Being rich in compounds with high antioxidant activity, the rosemary extract can be used to replace synthetic antioxidants used in vegetable oils. [ABSTRACT FROM AUTHOR]