•Degree of hydrolysis of milk proteins varied with probiotic strains.•Probiotic yogurt produced peptides of high antioxidative and antimutagenic potential.•Degree of hydrolysis correlated with ...antioxidative activity of peptide extract.•Degree of hydrolysis correlated with antimutagenic activity of peptide extract.
Search for bioactive peptides is intensifying because of the risks associated with the use of synthetic therapeutics, thus peptide liberation by lactic acid bacteria and probiotics has received a great focus. However, proteolytic capacity of these bacteria is strain specific. The study was conducted to establish proteolytic activity of Lactobacillus acidophilus (ATCC® 4356™), Lactobacillus casei (ATCC® 393™) and Lactobacillus paracasei subsp. paracasei (ATCC® BAA52™) in yogurt. Crude peptides were separated by high-speed centrifugation and tested for antioxidant and antimutagenic activities. The degree of proteolysis highly correlated with these bioactivities, and its value (11.91%) for samples containing all the cultures was double that of the control. Liberated peptides showed high radical scavenging activities with 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), IC50 1.51 and 1.63mg/ml, respectively and strong antimutagenicity (26.35%). These probiotics enhanced the generation of bioactive peptides and could possibly be commercially applied in new products, or production of novel anticancer peptides.
► Germination manipulated concentrations of bioactive compounds in selected grains. ► Grain and treatment dependant inhibition of α-glucosidase and α-amylase activities. ► Concentration of bioactives ...mainly increased, especially antioxidants and GABA. ► Barley, sorghum and rye may reduce risk of diabetes and colon cancer.
Germination of seven selected commercially important grains was studied to establish its effects on the nutritional and chemical composition. The changes in the concentration of the nutrients, bioactive compounds and the inhibitory effect of extracts on α-glucosidase and α-amylase activities were investigated. These were measured through proximate analysis, inhibition assays and HPLC. Germinated sorghum and rye extracts inhibited (p<0.05) α-glucosidase activity, whereas barley and sorghum extracts exhibited higher inhibitory activities against α-amylase. Germinated grains contained substantial amounts of total phenolics with rye having significantly higher content compared with the non-germinated grains. Radical scavenging activities of the phenolic extracts were between 13% and 73% for non-germinated and 14% and 53% for germinated. Inositol phosphate (InsP) 4, 5 and 6 were noted in all the grains, but InsP 6 was significantly lower in concentration. This study indicates the potential of germinated barley, sorghum and rye for the development of effective physiologically bioactive compounds for the reduction of the risk of diabetic agents and colon cancer.
Bioactive compounds released during milk fermentation by proteolytic cleavage of milk proteins have a role beyond their nutritional importance. This study assessed the proteolytic activity of ...Lactobacillus helveticus strains ASCC953, ASCC474, ASCC1188, and ASCC1315 and their ability to release bioactive compounds capable of exerting antioxidative and in vitro anticarcinogenic properties during incubation at 37°C in reconstituted skim milk. The performance of these strains was not affected by the pH decline during fermentation. Soluble extracts of fermented milk by L. helveticus 474 showed the highest free radical (1,1-diphenyl-2-picrylhydrazyl) scavenging activity at 12 h of fermentation, followed by a significant reduction of this activity at 24 h compared with the other strains and control (untreated milk). Skim milk fermented by L. helveticus strains contained compounds with anti-colon cancer activity at varied levels during fermentation. The activity (19.03–50.98% growth inhibition) was greatest in the extract obtained after 12 h of fermentation, which markedly declined (5.4–9.94%) at the end of fermentation. Lactobacillus helveticus 1315 released compounds into the skim milk supernatant with a greater growth inhibition (50.98%) on colon cancer HT-29 cell line than the other strains. More importantly, these compounds had no significant inhibition effect on normal, primary colon cells T4056. Whereas these results suggest that milk fermented by L. helveticus strains may release bioactive compounds with important multifunctional properties, the characteristics and activities of these compounds appear highly strain- and fermentation time-dependent.
Short-chain fatty acids (SCFAs) have been recognized as mediators of immune responses, including pathways of cytokine production. In this study, we investigated the immune-regulatory effects of SCFAs ...on human peripheral blood mononuclear cells (PBMCs) from buffy coat of healthy donors. PBMCs were exposed to varying concentrations of individual SCFAs or of their mixtures of acetate, propionate and butyrate. The productions of interleukin (IL) IL-1β, IL-2, IL-6, IL-10, IL-17, IL-21, IL-23 and transforming growth factor beta 1 (TGF-β1) were assessed. T cell differentiation after exposure to SCFAs was also examined. Compared with lipopolysaccharide (LPS)-stimulated cells (controls), SCFAs slightly decreased TGF-β1 production and reduced IL-6 production; butyrate was more effective than acetate or propionate. SCFAs particularly butyrate caused the induction of CD4+CD25+ regulatory T cells (Treg) rather than Th17 cells. SCFAs may up-regulate the production of anti-inflammatory cytokines in PBMCs, resulting in the induction of CD4+CD25+ Treg cells.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Prawn allergy is one of the most common food-borne allergies and current prevention is by avoidance. This review paper summarised different methodologies for the extraction, identification and ...quantification of prawn protein allergens, reported in various research studies. Following extraction, allergenic components have been analysed using well-established methodologies, such as SDS-PAGE, Immunoblotting, ELISA, CD Spectroscopy, HPLC, DBPCFC, SPT etc. Moreover, the preference towards Aptamer-based technique for allergenicity analysis has also been highlighted in this review paper. The summary of these methodologies will provide a reference platform for present and future research directions.
Display omitted
•Effective separation and visualization of proteins depend on SDS PAGE gel concentrations.•Sandwich ELISA is more precise than indirect and Inhibition ELISA for allergenicity quantification.•Aptamers provides more specific immunogenic reaction for allergens than antibodies.•Allergenic proteins can be isolated by reversed-phase, anion-exchange and hydrophobic interaction HPLC methods.•This review paper will provide a better platform for present and future research direction on allergenic prawn proteins.
The study determined β-glucosidase activity of commercial probiotic organisms for hydrolysis of isoflavone to aglycones in fermenting soymilk. Soymilk made with soy protein isolate (SPI) was ...fermented with Lactobacillus acidophilus LAFTI® L10, Bifidobacterium lactis LAFTI® B94, and Lactobacillus casei LAFTI® L26 at 37 °C for 48 h and the fermented soymilk was stored for 28 d at 4 °C. β-Glucosidase activity of organisms was determined using ρ-nitrophenyl β-D-glucopyranoside as a substrate and the hydrolysis of isoflavone glycosides to aglycones by these organisms was carried out. The highest level of growth occurred at 12 h for L. casei L26, 24 h for B. lactis B94, and 36 h for L. acidophilus L10 during fermentation in soymilk. Survival after storage at 4 °C for 28 d was 20%, 15%, and 11% greater (P < 0.05) than initial cell counts, respectively. All the bacteria produced β-glucosidase, which hydrolyzed isoflavone β-glycosides to isoflavone aglycones. The decrease in the concentration of β-glycosides and the increase in the concentration of aglycones were significant (P < 0.05) in the fermented soymilk. Increased isoflavone aglycone content in fermented soymilk is likely to improve the biological functionality of soymilk.
Bioactive peptides are food derived components, usually consisting of 3-20 amino acids, which are inactive when incorporated within their parent protein. Once liberated by enzymatic or chemical ...hydrolysis, during food processing and gastrointestinal transit, they can potentially provide an array of health benefits to the human body. Owing to an unprecedented increase in the worldwide incidence of obesity and hypertension, medical researchers are focusing on the hypotensive and anti-obesity properties of nutritionally derived bioactive peptides. The role of the renin-angiotensin system has long been established in the aetiology of metabolic diseases and hypertension. Targeting the renin-angiotensin system by inhibiting the activity of angiotensin-converting enzyme (ACE) and preventing the formation of angiotensin II can be a potential therapeutic approach to the treatment of hypertension and obesity. Fish-derived proteins and peptides can potentially be excellent sources of bioactive components, mainly as a source of ACE inhibitors. However, increased use of marine sources, poses an unsustainable burden on particular fish stocks, so, the underutilized fish species and by-products can be exploited for this purpose. This paper provides an overview of the techniques involved in the production, isolation, purification, and characterization of bioactive peptides from marine sources, as well as the evaluation of the ACE inhibitory (ACE-I) activity and bioavailability.
Introduction:
Calpain is a cysteine protease that participates in normal signal transduction events, but deregulation of its action may result in pathologies such as neurological disorders, muscular ...dystrophies, cataract, cancer and diabetes. Inhibition of calpain is demonstrably beneficial in animal models of these diseases; hence, the enzyme has been proposed as a potential drug target.
Areas covered:
A comprehensive review of calpain inhibitors reported in the patent and scientific literature over the past decade (2001 - 2010) is presented in this paper. Peptides, peptidomimetics and nonpeptide inhibitors with and without reactive warheads are discussed. Advances made in enhancing the cellular uptake of peptide calpain inhibitors, improving the pharmacokinetic properties of the inhibitors and site specific targeting of calpain inhibitors are also discussed.
Expert opinion:
Calpain inhibitors have demonstrated efficacy in animal models of calpain related diseases, but progression of the inhibitors into clinical trials has been hampered partly due to lack of calpain isoform selectivity and the general reactivity of the inhibitors. Therefore, efforts should be directed towards the discovery of compounds devoid of these problems. Exploration of compounds that bind to allosteric sites of the enzyme may circumvent these problems and afford new drug leads.
Fruit by-products are good resources of carbohydrates, proteins, vitamins, and minerals, which may function as growth nutrients for probiotic bacteria. This research aimed at evaluating effects of ...pineapple peel powder addition on the viability and activity of Lactobacillus acidophilus (ATCC 4356), Lactobacillus casei (ATCC393), and Lactobacillus paracasei ssp. paracasei (ATCC BAA52) in yogurts throughout storage at 4°C for 28d. Plain and probiotic yogurts supplemented with or without pineapple peel powder or inulin were prepared. The probiotic counts in supplemented yogurts at 28d of storage ranged from 7.68 and 8.03 log cfu/g, one log cycle higher compared with nonsupplemented control yogurt. Degree of proteolysis in synbiotic yogurts was significantly higher than plain yogurts and increased substantially during storage. Crude water-soluble peptide extract of the probiotic yogurt with peel possessed stronger antimutagenic and antioxidant activities evaluated measuring reducing power and scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl; 2,2’-azino-bis(3-ethyl benzothiazoline-6-sulfonic acid), and hydroxyl radicals than control and maintained during storage. Pineapple peel, a by-product of juice production, could be proposed as a prebiotic ingredient in the manufacture of yogurts with enhanced nutrition, and functionality.
The viability of
Lactobacillus acidophilus LAFTI
® L10,
Bifidobacterium lactis LAFTI
® B94, and
L. paracasei LAFTI
® L26 and their proteolytic activities were assessed in yoghurt at different ...termination pH of 4.45, 4.50, 4.55, and 4.60 in the presence of
L. delbrueckii ssp
. bulgaricus Lb1466 and
Streptococcus thermophilus St1342 during 28 days of storage at 4
°C. All strains achieved the recommended level of 6.00
log
cfu
g
−1 of the product with
L. acidophilus LAFTI
® L10 and
L. paracasei LAFTI
® L26 exceeding the number to 8.00 and 7.00
log
cfu
g
−1, respectively. Lactobacilli strains showed a good cellular stability maintaining constant concentration throughout storage period regardless of termination pH. On the other hand, the cell counts of
B. lactis LAFTI
® B94 decreased by one log cycle at the end of storage. The presence of probiotic organisms enhanced proteolysis significantly in comparison with the control batch containing
L. delbrueckii ssp
. bulgaricus Lb1466 and
S. thermophilus St1342 only. The proteolytic activity varied due to termination pH, but also appeared to be strain related. The increased proteolysis improved survival of
L. delbrueckii ssp
. bulgaricus Lb1466 during storage resulting in lowering of pH and production of higher levels of organic acids, which might have caused the low cell counts for
B. lactis LAFTI
® B94.
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