Reducing Immunoreactivity of Gluten Peptides by Probiotic Lactic Acid Bacteria for Dietary Management of Gluten-Related Diseases.

Immunoreactive gluten peptides that are not digested by peptidases produced by humans can trigger celiac disease, allergy and non-celiac gluten hypersensitivity. The aim of this study was to evaluate the ability of selected probiotic strains to hydrolyze immunoreactive gliadin peptides and to identify peptidase-encoding genes in the genomes of the most efficient strains. Residual gliadin immunoreactivity was measured after one- or two-step hydrolysis using commercial enzymes and bacterial peptidase preparations by G12 and R5 immunoenzymatic assays. Peptidase preparations from Lacticaseibacillus casei LC130, Lacticaseibacillus paracasei LPC100 and Streptococcus thermophilus ST250 strains significantly reduced the immunoreactivity of gliadin peptides, including 33-mer, and this effect was markedly higher when a mixture of these strains was used. In silico genome analyses of L. casei LC130 and L. paracasei LPC100 revealed the presence of genes encoding peptidases with the potential to hydrolyze bonds in proline-rich peptides. This suggests that L. casei LC130, L. paracasei LPC100 and S. thermophilus ST250, especially when used as a mixture, have the ability to hydrolyze immunoreactive gliadin peptides and could be administered to patients on a restricted gluten-free diet to help treat gluten-related diseases.

Encapsulation and Biological Activity of Hesperetin Derivatives with HP-ß-CD.

The encapsulation of insoluble compounds can help improve their solubility and activity. The effects of cyclodextrin encapsulation on hesperetin's derivatives (HHSB, HIN, and HTSC) and the physicochemical properties of the formed complexes were determined using various analytical techniques. The antioxidant (DPPH•, ABTS•+ scavenging, and Fe2+-chelating ability), cytotoxic, and antibacterial activities were also investigated. The inclusion systems were prepared using mechanical and co-evaporation methods using a molar ratio compound: HP-ß-CD = 1:1. The identification of solid systems confirmed the formation of two inclusion complexes at hesperetin (CV) and HHSB (mech). The identification of systems of hesperetin and its derivatives with HP-ß-CD in solutions at pHs 3.6, 6.5, and 8.5 and at various temperatures (25, 37 and 60 °C) confirmed the effect of cyclodextrin on their solubility. In the DPPH• and ABTS•+ assay, pure compounds were characterized by higher antioxidant activity than the complexes. In the FRAP study, all hesperetin and HHSB complexes and HTSC-HP-ß-CD (mech) were characterized by higher values of antioxidant activity than pure compounds. The results obtained from cytotoxic activity tests show that for most of the systems tested, cytotoxicity increased with the concentration of the chemical, with the exception of HP-ß-CD. All systems inhibited Escherichia coli and Staphylococcus aureus.

Influence of the Microalga Chlorella vulgaris on the Growth and Metabolic Activity of Lactobacillus spp. Bacteria.

The aim of this study was to evaluate the effect of the algae Chlorella vulgaris on the growth, acidifying activity, proportion of lactic acid isomers, and enzymatic profile of Lactobacillus brevis (LOCK 0944, LOCK 0980, LOCK 0992, and MG451814) isolated from vegetable silages. The results indicated that adding algae at concentrations of 0.1% (w/v) and 1.5% (w/v) to the Lactobacillus spp. growth medium accelerated the growth of bacteria and thus shortened their phase of logarithmic growth. The acidifying activity of the tested Lactobacillus brevis increased with an increased concentration of algae. Lactobacillus spp. cultured in the presence of Chlorella vulgaris showed higher production of l-lactic acid and lower d-lactic acid production. Moreover, the addition of algae changed the enzymatic activity of lactic acid bacteria; for instance, Lactobacillus brevis LOCK 0980 demonstrated more enzymatic activity of valine arylamidase, α-galactosidase, and α-glucosidase. Combining Lactobacillus brevis with the algae Chlorella vulgaris allows for the creation of innovative, functional products which confer favorable properties to the final product and open new horizons for the food industry.

Algae in food: a general review.

Algae are common all over the Earth. Due to their rich chemical composition and content of bioactive substances they have been used in many fields of industry. Their gelling, thickening and stabilizing properties have led to the development of such products as agar, alginate and carrageenan. Moreover, algae are used in the food industry as food supplements and an addition to functional food. Algae are also added to meat products, such as pasty, steaks, frankfurters and sausages, as well as to fish, fish products, and oils, to improve their quality. Cereal-based products, such as pasta, flour and bread, are another group of products enriched with algae. Due to their properties algae may also be used for construction of fermented functional food. Fermented products containing algae are, most of all, dairy products, such as cheese, cream, milk deserts, yoghurt, cottage cheese, and processed cheese. Combination of fermented products offering a high content of lactic acid bacteria with algae possessing biologically active metabolites of natural origin allows not only to compose products with a high content of nutrients, but also to create a brand new segment of fermented food.