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Traditionally, cheese is manufactured by converting fluid milk to a semisolid mass through the use of a coagulating agent, such as rennet, acid, heat plus acid, or a combination thereof. Cheese can vary widely in its characteristics, including color, aroma, texture, flavor, and firmness, which can generally be attributed to the production technology, source of the milk, moisture content, and length of aging, in addition to the presence of specific molds, yeast, and bacteria. Among the most important bacteria, lactic acid bacteria (LAB) play a critical role during the cheese-making process. In general, LAB contain cell-envelope proteinases that contribute to the proteolysis of cheese proteins, breaking them down into oligopeptides that can be subsequently taken up by cells via specific peptide transport systems or further degraded into shorter peptides and amino acids through the collaborative action of various intracellular peptidases. Such peptides, amino acids, and their derivatives contribute to the development of texture and flavor in the final cheese. In vitro and in vivo assays have demonstrated that specific sequences of released peptides exhibit biological properties including antioxidant, antimicrobial, anti-inflammatory, immunomodulatory, and analgesic/opioid activity, in addition to angiotensin-converting enzyme inhibition and antiproliferative activity. Some LAB also produce functional lipids (e.g., conjugated linoleic acid) with anti-inflammatory and anticarcinogenic activity, synthesize vitamins and antimicrobial peptides (bacteriocins), or release γ-aminobutyric acid, a nonprotein amino acid that participates in physiological functions, such as neurotransmission and hypotension induction, with diuretic effects. This review provides an overview of the main bioactive components present or released during the ripening process of different types of cheese.

Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or antimicrobial) have been previously well documented; however, few studies describe multifunctional bioactive peptides, which may be preferred over single-activity peptides, as they can simultaneously trigger, modulate, or inhibit multiple physiological pathways. Hence, the aim of this study was to assess the anti-inflammatory, antihemolytic, antioxidant, antimutagenic, and antimicrobial activities of crude extracts (CE) and peptide fractions (<3 and 3-10 kDa) obtained from fermented milks with specific Lactobacillus plantarum strains. Overall, CE showed higher activity than both peptide fractions (<3 and 3-10 kDa) in most of the activities assessed. Furthermore, activity of <3 kDa was generally higher, or at least equal, to the 3 to 10 kDa peptide fractions. In particular, L. plantarum 55 crude extract or their fractions showed the higher anti-inflammatory (723.68-1,759.43μg/mL of diclofenac sodium equivalents), antihemolytic (36.65-74.45% of inhibition), and antioxidant activity [282.8-362.3µmol of Trolox (Sigma-Aldrich, St. Louis, MO) equivalents]. These results provide valuable evidence of multifunctional role of peptides derived of fermented milk by the action of specific L. plantarum strains. Thus, they may be considered for the development of biotechnological products to be used to reduce the risk of disease or to enhance a certain physiological function.

Aims:  To assess the ability of five probiotic bacteria to bind aflatoxin B1 and to determine the key role of teichoic acids in the binding mechanism. Methods and Results:  The strains were incubated in aqueous solutions containing aflatoxin B1 (AFB1). The amount of free toxin was quantified by HPLC. Stability of the bacteria–aflatoxin complex was evaluated by repeated washes with buffer. In order to understand the binding process, protoplasts, spheroplasts and cell wall components of two strains were analysed to assess their capacity to bind AFB1. Additionally, the role of teichoic acids in the AFB1 binding process was assessed. Lactobacillus reuteri strain NRRL14171 and Lactobacillus casei strain Shirota were the most efficient strains for binding AFB1. The stability of the AFB1–bacteria complex appears to be related to the binding ability of a particular strain; AFB1 binding was also pH‐dependent. Our results suggest that teichoic acids could be responsible for this ability. Conclusions:  Our results provide information concerning AFB1 binding by previously untested strains, leading to enhanced understanding of the mechanism by which probiotic bacteria bind AFB1. Significance and Impact of the Study:  Our results support the suggestion that some probiotic bacteria could prevent absorption of aflatoxin from the gastrointestinal tract.

The purpose of this work was to screen for and characterize the potential probiotic features of strains of lactic acid bacteria isolated from Galega cultivar fermented olives, to eventually develop an improved probiotic food from plant origin. From 156 isolated strains, 10 were acid e and bile salt tolerant, and exhibited survival rates up to 48%, following simulated digestion. All strains exhibited auto-(4-12%) and co-aggregation features (≥30%), as well as hydrophobicity (5-20%) and exopolysaccharide-producing abilities, while no strain possessed haemolytic capacity or ability to hydrolyse mucin. Antibiotic resistance, oleuropein degradation, proteolytic activity and antimicrobial activity were strain dependent features. Overall, 10 strains e belonging to Lactobacillus plantarum and Lactobacillus paraplantarum, appear to possess a probiotic value.2