Evaluation of probiotic potential of autochthonous lactobacilli strains isolated from Zabuli yellow kashk, an Iranian dairy product.

AIMS: The aim of this study was to evaluate the probiotic potential and anti-biofilm activity of five lactobacilli strains which isolated and identified from an Iranian product. METHODS AND RESULTS: Five lactobacilli strains, which were isolated from Zabuli yellow kashk, were evaluated for the presence of probiotic properties, such as resistance to low pH, resistance to simulated gastrointestinal conditions, bile salt tolerance, hydrophobicity, and auto- and co-aggregation. In addition, antimicrobial susceptibility, adherence to Caco-2 cells (human colon cancer cell line), anti-adhesion activity, ability against biofilm formation and biofilm degradation of mentioned strains against Pseudomonas aeruginosa PTCC 1707 were assessed. All the strains tested showed acceptable characteristics, but Lactiplantibacillus plantarum TW57-4 appeared of particular interest. Some probiotic properties of this strain were similar and in some cases higher than the commercial probiotic strain Lacticaseibacillus rhamnosus GG (standard sample). Cholesterol assimilation and radical-scavenging activity of Lpb. plantarum TW57-4 were 70.2% and 62.3%, respectively. The adhesion degree of Lpb. plantarum TW57-4 was 10.6%. Applying competition and inhibition assay, this strain showed 55.3% and 62.3% of competition and inhibition activity in adhesion of P. aeruginosa PTCC 1707 to the intestinal cells, respectively. CONCLUSIONS: According to the obtained results, it can be concluded that Lpb. plantarum TW57-4 strain can be used as a promising candidate for in-vivo studies with the aim of developing new probiotic starter cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study furthers our understanding of lactobacilli strains behaviour after consumption to establish their beneficial effects.

Aggregation, adherence, anti-adhesion and antagonistic activity properties relating to surface charge of probiotic Lactobacillus brevis gp104 against Staphylococcus aureus.

Positive effects of fermented foods consumption on humans have stimulated lots of research attention. In this study, we investigated the probiotic potentials, antagonistic activities, and safety properties of Lactobacillus brevis gp104 isolated from Iranian traditional cheese. The results showed that the strain had high resistance to acidic conditions, simulated gastric and intestinal fluid. L. brevis gp104 was able to assimilate cholesterol from the medium; 41% in medium without bile salts and 58% in medium with bile salts. The potential of this strain was relatively low in phytate hydrolyzation and 62.02% hydrophobicity, 40.2% auto-aggregation, and 48.3% co-aggregation were observed. The adhesion value of L. brevis gp104 to adenocarcinoma Caco-2 cells was 13.4% that was also confirmed by scanning electron microscopy (SEM). Antibacterial effect of L. brevis fg104 was imposed against pathogenic strains (Escherichia coli ATCC 25922, Pseudomonas aeruginosa PTCC 1707, Salmonella typhimurium PTCC 1609, and Staphylococcus aureus ATCC 25923) and the most sensitive strain S. aureus. L. brevis gp104 was able to compete (52%), inhibit (47%) and displace (21%) the adhesion of S. aureus to Caco-2 cells. L. brevis gp104 did not show haemolytic or DNase activity, which confirms its safety aspects. Therefore, L. brevis gp104 was demonstrated promising properties for its potential health benefits for its application as novel bio-therapeutic and bio-preservation agents.

Inhibition of Escherichia coli adhesion to human intestinal Caco-2 cells by probiotic candidate Lactobacillus plantarum strain L15.

Probiotics are microbial strains beneficial to human health if consumed in appropriate amounts. Their potential has recently led to a significant increase in research interest in their effects on the intestine, mainly by reinforcing the intestinal epithelium and modulating the gut microbiota. This study aimed to evaluate the probiotic features of Lactobacillus plantarum strain L15 based on adhesive properties for the inhibition of the adhesion of infectious pathogens. The molecular identification of the strain was performed from the sequencing of 16S ribosomal DNA with 27FYM and 1492R primers, and its probiotic features, including resistance to gastric juices, resistance to bile salts, and hydrophobicity were evaluated. The potential of Lactobacillus plantarum strain L15 to adhere to human adenocarcinoma intestinal cell line, Caco-2, as well as the auto and co-aggregation and anti-adherence activity against Escherichia coli were investigated. The results demonstrated that this strain has a desirable potential for passing through the low pH of the stomach and entering the intestines. Moreover, 54% hydrophobicity, 44% auto-aggregation, and 32% co-aggregation were observed for this strain. The adhesion level of Lactobacillus plantarum strain L15 to Caco-2 cells was 12%, and adhered lactobacilli cells were observed by scanning electron microscopy (SEM). Furthermore, this strain showed appropriate anti-adherence effects, including competition, inhibition, and replacement properties against Escherichia coli. The results indicated that Lactobacillus plantarum strain L15 had good potential for exerting antagonistic effects against E. coli.

Cumin essential oil: Phytochemical analysis, antimicrobial activity and investigation of its mechanism of action through scanning electron microscopy.

In this study, the antimicrobial effects of cumin essential oil (CEO) and its mechanism of action through scanning electron microscopy (SEM) against Escherichia coli and Listeria innocua were investigated. The SEM images were taken at 0, 12 and 24 h at the minimum inhibitory concentration (MIC). The chemical composition of CEO was identified through gas chromatography/mass spectrometry (GC-MS). The antimicrobial effects of CEO were evaluated by the methods of Kirby-Bauer, well diffusion agar, microdilution broth and minimum bactericidal/fungicidal concentration (MBC/MFC). Antioxidant activity was examined by the methods of ß-carotene/linoleic acid inhibition and 2,2-diphenyl-1-picrylhydrazyl. Total phenol content (TPC) was measured by Folin-Ciocalteu method. The subsequent analysis of CEO through GC-MS revealed that cuminal (28.28%) was the major compound of CEO. CEO showed a high TPC of 89.45 ±â€¯0.78 mg GAE/g. The free radical scavenging activity of CEO (based on IC50) was equal to 9.10 ±â€¯0.63 µg mL-1. In addition, CEO showed a remarkably high inhibitory effect (63%) on ß-carotene bleaching via neutralizing hydroperoxides, which are responsible for the oxidation of highly unsaturated ß-carotene. The antimicrobial effect increased as a function of essential oil concentration. However, there were no inhibitory effects on E. coli at 5 mg mL-1. The electron micrographs demonstrated that CEO caused an increase in the permeabilization of the cells and disrupted the membrane integrity.

Evaluation of adherence and anti-infective properties of probiotic Lactobacillus fermentum strain 4-17 against Escherichia coli causing urinary tract infection in humans.

Gastrointestinal (GI) infection is one of the most common types of infectious diseases. Application of probiotic strains in the control of such infections represents a promising approach. In this study, Lactobacillus fermentum strain 4-17 was isolated from kashkineh, an Iranian cereal fermented food, and identified by sequencing its 16S rRNA gene using universal primers. Its probiotic features, including resistance to acid, bile tolerance, antibacterial activity, resistance to intestinal and gastric juices, and hydrophobicity were evaluated. The ability of this strain to adhere to human intestinal cells as well as the anti-adhesive effect of L. fermentum strain 4-17 against E. coli isolated from patients with urinary tract infection was investigated. L. fermentum strain 4-17 was capable of surviving at various conditions such as low pH values, bile salts exposure, and GI tract environment. It showed 43% cell hydrophobicity. The adhesion level of L. fermentum strain 4-17 to human colon adenocarcinoma Caco-2 cells was 8.5% which was also confirmed by scanning electron microscopy (SEM). Furthermore, this strain showed appropriate anti-adhesive properties (including competition, inhibition and replacement properties) against human pathogenic bacteria. These data suggest that L. fermentum strain 4-17 could be examined further for its useful effects and introduced as a novel candidate probiotic to control GI infection disease.

Exploring the Nutritional Impact of Sourdough Fermentation: Its Mechanisms and Functional Potential.

Sourdough fermentation is one of the oldest traditional methods in food technology and occurs as a result of fermentation of flour prepared from grains. The nutritional role of sourdough is related to the final composition of fermented foods prepared through sourdough fermentation, and recently, sourdough has become an important application to improve nutrition characteristics of bread. Thanks to lactic acid bacteria (LAB) presented in sourdough microflora and metabolites partially produced by yeasts, technological and important nutritional features of the bread improve and an increase in shelf life is achieved. In addition, sourdough bread has a low glycemic index value, high protein digestibility, high mineral and antioxidant content, and improved dietary fiber composition, making it more attractive for human nutrition compared to regular bread. When the sourdough process is applied, the chemical and physical properties of fibers vary according to the degree of fermentation, revealing the physiological importance of dietary fiber and its importance to humans' large intestine microbiota. Therefore, taking these approach frameworks into consideration, this review highlights the benefits of sourdough fermentation in increasing nutrient availability and contributing positively to support human health.

Bio-synthesis, purification and structural analysis of Cyclosporine-A produced by Tolypocladium inflatum with valorization of agro-industrial wastes.

Cyclosporine A (CyA) holds significant importance as a strategic immunosuppressive drug for organ transplant patients. In this study, we aimed to produce pure and cost-effective Cyclosporine A (CyA) by fermenting a culture medium containing dairy sludge, using Tolypocladium inflatum PTCC 5253. Following the fermentation stage, ethyl acetate extraction and fast protein liquid chromatography were employed for sample purification. The initial evaluation of the effectiveness of CyA obtained from these processes was performed through bioassay, wherein the antimicrobial clear zone diameter was found to be larger compared to the sample obtained from the fermentation culture. The concentration of CyA was determined using high-performance liquid chromatography, yielding values of 334 mg/L, 456 mg/L, and 578 mg/L for the fermented, extracted, and purified samples, respectively. Further analysis utilizing liquid chromatography tandem mass spectrometry (LC/MS/MS) confirmed a purity of 91.9% and proper agreement with the standard sample based on the ion intensity of Z/m 1205. To validate the structure of CyA, nuclear magnetic resonance spectroscopy, Fourier-transform infrared (FT-IR), and Raman spectroscopy were employed. X-ray diffraction and differential scanning calorimetry analyses demonstrated that the purified CyA exhibited a crystal structure similar to the standard sample, characterized by two broad peaks at 2θ = 9° and 20°, and comparable glass transition temperatures (57-68 °C for the purified sample; 53-64 °C for the standard sample). Dynamic light scattering analysis confirmed a uniform particle size distribution in both the purified and standard samples. The zeta potentials of the purified and standard samples were determined to be - 25.8 ± 0.16 and - 23.63 ± 0.12 mV, respectively. Our results demonstrate that dairy sludge can serve as a suitable culture medium for the production of (CyA).

Investigating the Effect of Melittin Peptide in Preventing Biofilm Formation, Adhesion and Expression of Virulence Genes in Listeria monocytogenes.

Listeria monocytogenes is a notable food-borne pathogen that has the ability to create biofilms on different food processing surfaces, making it more resilient to disinfectants and posing a greater risk to human health. This study assessed melittin peptide's anti-biofilm and anti-pathogenicity effects on L. monocytogenes ATCC 19115. Melittin showed minimum inhibitory concenteration (MIC) of 100 µg/mL against this strain and scanning electron microscopy images confirmed its antimicrobial efficacy. The OD measurement demonstrated that melittin exhibited a strong proficiency in inhibiting biofilms and disrupting pre-formed biofilms at concentrations ranging from 1/8MIC to 2MIC and this amount was 92.59 ± 1.01% to 7.17 ± 0.31% and 100% to 11.50 ± 0.53%, respectively. Peptide also reduced hydrophobicity and self-aggregation of L. monocytogenes by 35.25% and 14.38% at MIC. Melittin also significantly reduced adhesion to HT-29 and Caco-2 cells by 61.33% and 59%, and inhibited invasion of HT-29 and Caco-2 cells by 49.33% and 40.66% for L. monocytogenes at the MIC value. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) revealed melittin's impact on gene expression, notably decreasing inlB (44%) and agrA (45%) gene expression in L. monocytogenes. flaA and hly genes also exhibited reduced expression. Also, significant changes were observed in sigB and prfA gene expression. These results underscore melittin's potential in combating bacterial infections and biofilm-related challenges in the food industry.

Effect of a mobile-based educational app on blood pressure of patients with hypertension.

BACKGROUND: Hypertension is known as one of the most important non-communicable pervasive diseases. OBJECTIVE: The purpose of the present study was to determine the effect of a mobile-based educational app on the blood pressure (BP) of patients with hypertension. METHODS: This clinical trial was conducted on 66 military personnel who were definitively diagnosed with hypertension by a physician, and then assigned randomly into two groups as intervention (receiving mobile-based educational app) and control (receiving standard medical management but no app). Before the intervention, BP levels of both groups were measured with a calibrated sphygmomanometer. After 6 weeks, the BPs of both groups were remeasured using the same sphygmomanometer. Thereafter, descriptive and inferential statistics, including paired t-test, Mann-Whitney, Chi-square and Wilcoxon tests, were used. The data obtained were analysed using SPSS-21 software at a significance level of p<0.05. RESULTS: Comparison of the intervention and control groups showed no statistically significant difference between the groups in systolic BP (p=0.479) and diastolic BP (p=0.851) in the pre-intervention phase, but after the intervention, systolic and diastolic BP levels were significantly lower in the intervention group than in the control group (p=0.0001). CONCLUSION: The results suggested that the mobile-based educational app had a significant effect on reducing BP in patients with hypertension. Therefore, using this app is recommended for those military personnel with hypertension.

The Effect of Plasma-Activated Water Combined with Rosemary Extract (Rosmarinus officinalis L.) on the Physicochemical Properties of Frankfurter Sausage during Storage.

This study investigated the impact of plasma-activated water (PAW) and rosemary extract on the bacterial inactivation and quality attributes of Frankfurter sausages during a 6-day storage period. The antibacterial activity, total phenol content (TPC), and total flavonoid content (TFC) of the rosemary extract were evaluated. The TPC of the rosemary extract was 89.45 mg gallic acid/g dry weight, while the TFC was 102.3 mg QE/g dry weight. Even at low concentrations, the rosemary extract effectively inhibited the growth of all the tested pathogens using the Well Diffusion Agar method (WDA). The sausages were treated with different concentrations of PAW and rosemary extract and stored for 1 and 6 days. Sample B (100% rosemary extract + PAW treatment) showed the greatest reduction in microbial load and was selected for further analysis. Throughout the storage period, Sample B exhibited no significant changes in pH, moisture content, textural parameters, or sensory evaluation compared to the control group. However, the hardness and color parameters (L*, a*) of Sample B decreased, while the TBARS value increased after 6 days of storage. The combination of PAW and rosemary extract, particularly Sample B, effectively inhibited bacterial growth in the Frankfurter sausages without compromising most quality attributes. Some changes in hardness, color, and lipid oxidation were observed over the extended storage period.

Safety, probiotic properties, antimicrobial activity, and technological performance of Lactobacillus strains isolated from Iranian raw milk cheeses.

The objective of this study was to investigate probiotic, antimicrobial, technological and safety properties of lactobacillus strains isolated from local Iranian cheese made from raw milk. Six different samples were prepared, after serial dilution, culture was performed on MRS culture medium. The gram-positive and catalase-negative lactobacillus strains were subjected to grouping and identifying using biochemical tests, carbohydrates fermentation profiles, and 16S rDNA analysis. The results of sequence analysis showed the Lactobacillus spp. belonged to Lactobacillus brevis, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei. After 3 hr incubation at pH=2, 3-6 log units of strains decreased which Lactobacillus acidophilus (B14) and Lactobacillus brevis (B2) showed highest resistance to low pH as well as simulated GIT juices. The highest and lowest hydrophobicity degree was belonged to L. acidophilus (B14) (65.9%) and L. casei (B22) (25.6%), respectively. Also, the highest auto-aggregation and coaggregation were observed in L. acidophilus (B14) (51.3%) and L. plantarum (B20) (43.6%). The adhered percentage of strains varied from 2.5% to 14.6%. L. plantarum (B20) showed highest proteolytic activity followed by L. acidophilus (B14). Also, the highest autolytic activity belonged to L. acidophilus (B14). All of the strains showed low acidifying potential, except for L. acidophilus (B17) which decreased 2.05 unit of pH after 24 hr. The isolates did not show lipolytic activity as well as biogenic amines production (except L. brevis B3). All of the strains were sensitive to chloramphenicol and erythromycin except L. acidophilus (B15) and L. casei (B22). All strains showed no hemolysis activity which make them safe for consumption. Based on the obtained results, L. acidophilus (B14) presented the best probiotic and technological characteristics and is proposed for using as coculture in the dairy industrial.

Control of microbial growth and lipid oxidation in beef using a Lepidium perfoliatum seed mucilage edible coating incorporated with chicory essential oil.

In this study, chicory essential oil (CEO) was obtained by hydrodistillation-based extraction method and it was rich in camphor (31.3%) and phenolic compounds with outstanding antioxidant and antimicrobial properties. The CEO was then incorporated into Lepidium perfoliatum seed mucilage (LPSM) based aqueous solution to prepare an active CEO-loaded LPSM edible coating. The effect of the edible coating was then investigated on the quality and shelf life of beef slices during 7 days storage at 4°C. The results revealed that beef slice coated with CEO-loaded LPSM edible coating had a significant inhibitory effect on its lipid oxidation and microbial growth. The CEO-LPSM coating also inhibited the weight and texture losses of beef slices during display more efficiently compared with the control and CEO-free LPSM coating. Besides, the beef slices coated with CEO-LPSM were the preferred samples in terms of sensory scores throughout the storage. Thus, using CEO-rich LPSM edible coating might inhibit decay and significantly improve the shelf life of fresh beef.

Preparation and Functional Properties of Synbiotic Yogurt Fermented with Lactobacillus brevis PML1 Derived from a Fermented Cereal-Dairy Product.

Nowadays, production of functional foods has become very essential. Inulin is one of the most functional hydrocolloid compounds used in such products. In the present study, the production of a synbiotic yogurt containing 1, 2.5, and 5% (w/v) inulin has been investigated. The yogurt was fermented with Lactobacillus brevis PML1 derived from Tarkhineh, an Iranian cereal-dairy fermented food. Furthermore, the physicochemical properties, antioxidant activity, sensory attributes, and microbial viability properties were investigated on the 0th, 7th, and 14th days of storage after fermentation. The viable cells of L. brevis PML1 reached 108 CFU/g, and the product resisted to simulated digestive juices. Moreover, the synbiotic yogurt impressively increased the production of antimicrobial compounds and had the most profound antimicrobial effect on S. typhimurium. The physiochemical properties were in the normal range, and the fat content of the synbiotic yogurt was reduced remarkably. The antioxidant capacity of the fermented yogurt was significantly increased (p < 0.05), which was equal to those of DPPH (69.18 ± 1.00%) and BHA (89.16 ± 2.00%). The viability of L. brevis PML1 was increased during storage. Sensory analysis showed that there were significant differences in terms of the impressive parameters between the samples and the control (p < 0.05). Addition of 2.5% inulin not only improved the physical properties but also retained the viability of the probiotic after 14 days of storage, in addition to the viability of L. brevis with a viability count above 6 log CFU/g in the yogurt. Therefore, a novel synbiotic product containing L. brevis PML1, which can exert the desired properties, can be used as a suitable carrier for the delivery of the probiotic strain, exerting its beneficial health effects.

Optimization of gamma-aminobutyric acid production by Lactobacillus brevis PML1 in dairy sludge-based culture medium through response surface methodology.

Gamma-aminobutyric acid (GABA) is a pharmaceutical, bioactive amino acid that can produce by some species of Lactic Acid Bacteria (LAB). For the first time, we evaluated the production of GABA by Lactobacillus brevis PML1 in the medium that contain the contaminant food bio-product like dairy sludge and soybean meal. GABA production was analyzed by chromatography (TLC, HPLC) and the features of fermented extract which contains this amino acid were evaluated. The results of Response Surface Methodology (RSM) of Central Composite Design (CCD) at p < .05 showed 300 ppm of GABA production in optimal treatment including 14.77% dairy sludge powder, 6.27% soybean meal, and 0.49% ammonium sulfate (32°C for 120 hr fermentation). The results of fermented extract also showed the acceptable antimicrobial, antioxidant, and toxicity (against cancer cell) properties. Also, L. brevis PML1has not shown any hemolytic or DNase activity which confirm its safety aspects. According to the results, this new culture can be used as a cheap substrate to biological production of GABA, by L. brevis PML1 in various food and pharmaceutical formulations.

Probiotic characterization of Pediococcus strains isolated from Iranian cereal-dairy fermented product: Interaction with pathogenic bacteria and the enteric cell line Caco-2.

In present study, we investigated the probiotic potential of three Pediococcus spp. isolated from Iranian traditional fermented cereal-dairy product, Tarkhineh. These 3 strains were identified as Pediococcus acidilactici VKU2, P. acidilactici IAH-5 and P. pentosaceus DHR005 by 16S rRNA gene sequencing. All the strain were found tolerate to pH 3 and 0.3% oxall for 3 h as well as simulated gastric and intestinal juice. P. acidilactici IAH-5 showed the highest cholesterol removal (67.52%), hydroxyl radical scavenging activity (58.32%), hydrophobicity (40.3%) and auto-aggregation (48%). Pediococcus spp. inhibited the growth of tested pathogens (Escherichia coli ATCC 25922, Pseudomonas aeruginosa PTCC 1707, Salmonella typhimurium PTCC 1609, and Staphylococcus aureus ATCC 25923) which the most susceptible strain was S. aureus. In competition assay, P. acidilactici IAH-5 was able to inhibited adhesion of 67.3% of S. typhimurium and in inhibition assay 45.8% of the pathogenic adhesion to Caco-2 cells were decreased. P. acidilactici VKU2 and P. acidilactici IAH-5 showed 16.32 and 12.25% adhesion to simulated epithelial cell line which were also confirmed by scanning electron microscopy. Pediococcus spp. did not showed DNase production or hemolytic activity which confirm its safety aspects. Our findings suggested that the P. acidilactici IAH-5 has the best properties with probiotic features and cholesterol assimilation for its application as novel bio-therapeutic and bio-preservation agents.

Gamma-aminobutyric acid production by Lactobacillus brevis A3: Optimization of production, antioxidant potential, cell toxicity, and antimicrobial activity.

In this study, whey powder was used as the basic compound for fermentation culture and the production of bioactive gamma-aminobutyric acid (GABA) compound. GABA is a nonprotein four-carbon amino acid that inhibits stress signals by preventing brain signals, reducing stress, and being effective in treating neurological disorders and decreasing the growth of cancer cells. Due to the side effects caused by the chemical type of GABA, the biological production of GABA has attracted. Three levels of whey powder (5%, 10%, and 15%), and monosodium glutamate (MSG) (1%, 3%, and 5%) were selected at temperatures (25, 30, and 37°C) and after fermentation, the presence of GABA in the culture medium was examined by thin-layer chromatography. The optimal amount of GABA was measured by using high-performance liquid chromatography. The results of the central composite design of the response surface methodology at a significant level of 95% showed that the optimal treatment was 14.96% whey powder, 4.95% MSG at temperature of 37°C and fermentation for 48 hr and under these conditions, GABA production was 553.5 ppm. The results of the fermented extract tests showed that the highest antimicrobial activity was on Escherichia coli and the highest free radical scavenging was 59.67%. The IC50 level in the Caco-2 cancer cell cytotoxicity test was 39.5 mg/ml. According to the results, the combination of whey with MSG can be used as a cheap substrate to produce a valuable bioactive GABA product, and the cellular extract of this fermentation can also be used as an antimicrobial and antioxidant compound in food and pharmaceutical formulations.

Oral Immunotherapy Using Probiotic Ice Cream Containing Recombinant Food-Grade Lactococcus lactis Which Inhibited Allergic Responses in a BALB/c Mouse Model.

This study was conducted to evaluate the effects of recombinant probiotic bacteria as a candidate for oral vaccine with the potential of treating allergy to Amaranthus retroflexus pollens. The main gene of this allergen, Ama r 2, was cloned into the food grade plasmid pNZ7025 and then was electrotransformed into the food grade Lactococcus lactis NZ1330. No expression was observed in the primary structure due to the distance between the ribosome binding site and the start codon. Therefore, the vector structure was corrected using the site-directed mutagenesis (SDM) technique. The cell extract of this strain was used for assessing the expression of the recombinant allergen in western blot analysis, and the existence of this protein with a molecular weight of 14.2 kDa was confirmed. To evaluate the efficacy of this strain in the treatment of allergies as an oral vaccine, probiotic ice cream was prepared. After the sensitization of mice, the treatment was performed by oral immunotherapy for 4 weeks, 4 to 5 times per week. 20 µl of functional ice cream with 1012 CFU/ml of r-L. lactis NZ1330 significantly reduced the serum IgE level. The levels of IFN-γ and TGF-ß cytokines increased in the 20 µl ice cream treatment group as well as 40 µg/ml pure allergen compared with the PBS-treated group, and IL-4 cytokine levels decreased compared with the PBS-treated group. Overall, 20 µl ice cream with 1012 CFU/ml of the recombinant bacteria resulted in the best performance in terms of improving allergies to Th1 and Treg responses.

Chemical Composition and Antioxidant, Antimicrobial, and Antiproliferative Activities of Cinnamomum zeylanicum Bark Essential Oil.

This study examines the chemical constituents, antioxidant potential, antibacterial mechanism, and antiproliferative activity of Cinnamomum zeylanicum bark essential oil. The compositions of the oil were analyzed by GC-MS, and the major constituents were found to be (E)-cinnamaldehyde (71.50%), linalool (7.00%), ß-caryophyllene (6.40%), eucalyptol (5.40%), and eugenol (4.60%). C. zeylanicum essential oil contained remarkable levels of phenolic and bioactive compounds with outstanding ability to scavenge free radicals and inhibit ß-carotene oxidation. The growth of pathogenic and spoilage bacteria, especially Gram-positive ones (i.e. Listeria innocua, Staphylococcus aureus, and Bacillus cereus), was highly inhibited by the oil, compared to the Gram-negative pairs (i.e. Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi). The cells of L. innocua and E. coli (as the most sensitive and resistant strains to the oil, respectively) treated with C. zeylanicum essential oil were observed by scanning electron microscopy to unravel structural changes. It was observed that the essential oil quickly exerted its antibacterial activity through disrupting cell envelope and facilitating the leakage of intracellular compounds. The essential oil had also a dose-dependent antiproliferative effect on adipose-derived mesenchymal stem cells (AT-MSCs), and the cell proliferation could be induced by low concentrations of the oil. The present study indicated that C. zeylanicum essential oil with remarkable antioxidant and antimicrobial properties could be applied to develop novel natural preservatives for food and medicinal purposes.

Antioxidant potential and antimicrobial activity of chitosan-inulin conjugates obtained through the Maillard reaction.

Chitosan (1%) was glycated with inulin (0.5, 1, and 2%) via the Maillard reaction at various initial pH values (5, 5.5, and 6). Higher pHs led to a greater pH drop and increase in the intermediate products and browning intensity (BI). The chitosan-inulin conjugates were then classified into three levels of low, medium, and high BI through K-means clustering in order to investigate the effect of BI development on the antioxidant and antimicrobial attributes of the conjugates. Covalent linkage between chitosan and inulin was confirmed by fourier transform infrared spectroscopy. High BI chitosan-inulin conjugate had significantly higher antioxidant property compared to chitosan and other conjugate fractions. In addition, the conjugates obtained at low pH values mainly presented greater antimicrobial activities than those prepared at high pHs. It can be concluded that chitosan-inulin Maillard-born conjugates can be used as novel antioxidant and antimicrobial prebiotic-based ingredients for food applications.