Characterization of Lactobacillus plantarum Lb41, an isolate from kimchi and its application as a probiotic in cottage cheese

Probiotic Lactobacillus plantarum Ln4 Showing Antimicrobial and Antibiofilm Effect against Streptococcus mutans KCTC 5124 Causing Dental Caries

Dental caries has known as an infectious disease that is considered a serious global public health problem. Recently, report indicate that probiotics play a vital role in maintaining oral health. Therefore, this study aimed to evaluate the prevention effects of Lactobacillus plantarum Ln4 against dental infection by the pathogenic bacterium Streptococcus mutans KCTC 5124 through biofilm formation inhibition. To evaluate such prevention effects against S. mutans KCTC 5124, antimicrobial activity, auto-aggregation, co-aggregation, cell surface hydrophobicity, total exopolysaccharide (EPS) production rate, and biofilm formation were analyzed. Results showed that L. plantarum Ln4 showed higher antimicrobial activity than L. rhamnosus GG (LGG). In the group treated with L. plantarum Ln4, the co-aggregation (58.85%), cell surface hydrophobicity (16.75%), and EPS production rate (73.29%) values were lower than those of LGG and the negative control. Additionally, crystal violet staining and confocal laser scanning microscopy (CLSM) revealed that L. plantarum Ln4 effectively inhibited biofilm formation in S. mutans KCTC 5124. Therefore, L. plantarum Ln4 could be used in the industry as a probiotics to prevent and improve oral health.

Synergistic Immunostimulatory Activities of Probiotic Strains, Leuconostoc lactis and Weissella cibaria, and the Prebiotic Oligosaccharides They Produce

Synbiotics contain health-beneficial bacteria, i.e., probiotics and prebiotics selectively utilized by the probiotics. Herein, three probiotic strains, Leuconostoc lactis CCK940, L. lactis SBC001, and Weissella cibaria YRK005, and the oligosaccharides produced by these strains (CCK, SBC, and YRK, respectively) were used to prepare nine synbiotic combinations. Macrophages (RAW 264.7) were treated with these synbiotic combinations and the corresponding lactic acid bacteria and oligosaccharides alone to evaluate the treatments' immunostimulatory activities. The level of nitric oxide (NO) production was significantly higher in the macrophages treated with the synbiotics than in those treated with the corresponding probiotic strains and the oligosaccharide alone. The immunostimulatory activities of the synbiotics increased regardless of the probiotic strain and the type of oligosaccharide used. The expressions of tissue necrosis factor-α, interleukin-1β, cyclooxygenase-2, inducible NO synthase genes, and extracellular-signal-regulated and c-Jun N-terminal kinases were significantly higher in the macrophages treated with the three synbiotics than in those treated with the corresponding strains or with the oligosaccharides alone. These results indicate that the synergistic immunostimulatory activities of probiotics and the prebiotics they produced in the studied synbiotic preparations resulted from the activation of the mitogen-activated protein-kinase-signaling pathway. This study suggests the combined use of these probiotics and prebiotics in the development of synbiotic preparations as health supplements.

Probiotic activity of ropy Lactiplantibacillus plantarum NA isolated from Chinese northeast sauerkraut and comparative evaluation of its live and heat-killed cells on antioxidant activity and RAW 264.7 macrophage stimulation

Lactic acid bacteria are known to have a positive impact on health and considered as functional supplements and additives. This study aimed to evaluate the probiotic properties of ropy Latilactobacillus isolated from Chinese northeast sauerkraut and to determine the antioxidant and immunoregulatory activities of its heat-killed cells compared to its live strains to assess its functional activity. After the analysis of the 16r DNA and phylogenetic tree, it was identified as a Lactiplantibacillus plantarum and named L. plantarum NA. L. plantarum NA was resistant to simulated gastrointestinal conditions in vitro. In addition, L. plantarum NA exhibited cholesterol degradation, antibiotic susceptibility, and antibacterial activity. Heat-killed L. plantarum NA exhibited antioxidant and immune-stimulating activities similar to live cells, which may be associated with the undamaged overall structure after heating. The results of antioxidant activity analysis suggested that both live and heat-killed L. plantarum NA possessed capacity for scavenging free radicals, including 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), hydroxyl radicals and superoxide radicals. The ABTS scavenging activity of heat-killed cells (38%) was significantly higher than that of viable (19%) L. plantarum NA. Furthermore, RAW 264.7 macrophages treated with L. plantarum NA induced the production of nitric oxide, cytokines (IL-6 and TNF-α), and reactive oxygen species (ROS). The NO/iNOS signaling pathway could be activated by L. plantarum NA and promoted NO production. Both live and heat-killed cells had a potential impact on the immunomodulatory activity, with different dosages. These results suggest that the novel L. plantarum NA isolated from Chinese northeast sauerkraut could be useful as a probiotic strain and applied to functional food processing and pharmaceutical fields as a potential immunomodulator.

Immune-Enhancing Effect of Heat-Treated Levilactobacillus brevis KU15159 in RAW 264.7 Cells

Probiotics are alive microbes that present beneficial to the human's health. They influence immune responses through stimulating antibody production, activating T cells, and altering cytokine expression. The probiotic characteristics of Levilactobacillus brevis KU15159 were evaluated on the tolerance and adherence to gastrointestinal conditions. L. brevis KU15159 was safe in a view of producing various useful enzymes and antibiotic sensitivity. Heat-treated L. brevis KU15159 increased production of nitric oxide (NO) and phagocytic activity in RAW 264.7 cells. In addition, heat-treated L. brevis KU15159 upregulated the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, at protein as well as mRNA levels. In addition, the mitogen-activated protein kinase (MAPK) pathway, which regulates the immune system, was activated by heat-treated L. brevis KU15159. Therefore, L. brevis KU15159 exhibited an immune-enhancing effect by the MAPK pathway in macrophage.

Food safety research and improvement of the technology of cottage cheese product with the use of green buckwheat

The purpose of thе article is to study the safety indicators of the curd product, which includes cottage cheese prepared with a starter culture of direct application "Evitalia," consisting of bacteria of the genus Lactococcus (L. acidophilius), Streptococcus (Streptococcus thermophilius) and propionobacteria. Other ingredients are crushed mass from green buckwheat, candied pumpkin, cooked Jerusalem artichoke sirup, and fat emulsion based on coconut oil. The sweetness of the curd product is provided by Jerusalem artichoke sirup, whereas fat emulsion based on coconut oil enriches the product with unsaturated fatty acids and gives plasticity and uniformity of structure. The results of the study showed that the formulation with the following ingredients: 40% of cottage cheese, 40% of crushed mass from green buckwheat, 10% of candied pumpkin, 10% of coconut oil emulsion-has the best organoleptic, physico-chemical, structural and plastic properties. The ratio of milk protein of cottage cheese and vegetable protein of green buckwheat is 1:1. This allowed to obtain the chemical composition of the product: proteins-29%, fats-9%, carbohydrates-59%, ash-3%. The obtained research and technological solutions can be used at dairy industry enterprises in the production of combined dairy and vegetable products.

The Anti-Cancer Potential of Heat-Killed Lactobacillus brevis KU15176 upon AGS Cell Lines through Intrinsic Apoptosis Pathway

Recent research has focused on the anti-cancer properties of Lactobacillus strains isolated from fermented foods. Their anti-cancer effects are caused by the apoptosis induction in cancer cells. However, sepsis, which can occur when cancer patients consume living organisms, can cause serious conditions in patients with reduced immunity because of cancer. Therefore, this study was conducted using heat-killed Lactobacillus brevis KU15176 (KU15176). To determine the relationship between inflammation and cancer, the anti-inflammatory effect of KU15176 was evaluated using a nitric oxide (NO) assay. Then, 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay was conducted to select cancer cells that showed the anti-proliferative effect of KU15176. Next, reverse transcription-polymerase chain reaction (RT-PCR), 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and caspase colorimetric assay were performed. As a result, it was confirmed that KU15176 could cause the increasing expression of apoptosis-related genes (Bax, caspase-3, and caspase-9), DNA breakage, effective apoptosis rate, and increased caspase activity in the human stomach adenocarcinoma (AGS) gastric cancer cell line. In conclusion, these results suggest a potential prophylactic effect of KU15176 against cancer.

Physicochemical analysis of non-fermented probiotic milk with probiotic Lactobacillus plantarum Ln1 isolated from Korea traditional fermented food

The objective of this study was to develop a non-fermented probiotic milk that maintains its physicochemical properties, microbial properties, antioxidant activity, and sensory properties during storage (0, 7, and 14 days). During storage, pH and viable cell counts decreased; however, titratable acidity increased. In addition, the composition and sensory characteristics of the non-fermented probiotic milk showed no significant differences between samples (MLN; milk with Lactobacillus plantarum Ln1, MGG; milk with Lactobacillus rhamnosus GG, and milk control). The antioxidant activities of MLN determined using 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, ABTS⁺ radical scavenging, and reducing power assay were higher during the examined storage periods when compared with those of the other samples. Overall, the physicochemical properties, microbial properties, and sensory factors of MLN showed no significant differences. However, high antioxidant activity was observed. Thus, we present a new functional dairy product with antioxidant activity.

Inhibitory effects of Lactobacillus brevis KU15153 against Streptococcus mutans KCTC 5316 causing dental caries

This study determined the inhibitory effect of Lactobacillus brevis KU15153 against cariogenic Streptococcus mutans KCTC 5316. Antimicrobial activity, auto-aggregation, cell surface hydrophobicity, exopolysaccharides (EPS) production, biofilm formation, and morphological changes were assessed in the presence of L. brevis KU15153. L. brevis KU15153 exhibited the highest antimicrobial activity against S. mutans KCTC 5316 (28.67 ± 4.16 mm). Auto-aggregation (38.32%), cell surface hydrophobicity (27.08%), and EPS production rate (58.52%) of S. mutans KCTC 5316 slightly decreased upon treatment with L. brevis KU15153. Additionally, crystal violet stanning and scanning electron microscopy confirmed the L. brevis KU15153-mediated inhibition of biofilm formation by S. mutans KCTC 5316 in comparison to that observed in the negative control (untreated S. mutans KCTC 5316). These results indicate that the L. brevis KU15153 could be used as a potential probiotic for maintaining oral health.

Probiotic properties of novel probiotic Levilactobacillus brevis KU15147 isolated from radish kimchi and its antioxidant and immune-enhancing activities

This study was conducted to evaluate the probiotic properties and antioxidant activities of lactic acid bacteria strains including Levilactobacillus brevis KU15147 isolated from kimchi to determine their potential as a probiotic. The tolerance of all strains to gastric acid and bile salts was more than 90%. The strains did not produce a β-glucuronidase and survived following treatment with gentamicin, kanamycin, streptomycin, and ciprofloxacin. L. brevis KU15147 showed greater adhesion activity to HT-29 cells (6.38%) and its antioxidant activities were higher than those of other tested strains, showing values of 38.56%, 22%, and 23.82% in DPPH, ABTS, and β-carotene bleaching assays, respectively. Additionally, the relative expression intensities of induced nitric oxide synthase and tumor necrosis factor-α of L. brevis KU15147 were greater than those of other strains, suggesting that this strain can be applied in the health food or pharmaceutical industry as a novel probiotic strain.

Fermented dairy products as delivery vehicles of novel probiotic strains isolated from traditional fermented Asian foods

The screening of novel probiotic strains from various food sources including fruits, vegetables, herbs, and traditional fermented foods, have been of growing concern recently. Most of these potential probiotic lactic acid bacteria isolates were distinguished from the commercial probiotics based on multiple therapeutic effects and functionalities. Recent in vitro and in vivo investigates have also verified the usage of probiotics to lower the risk of diseases. Application of these novel strains in fermented dairy products is also an emerging trend to improve the physical and quality characteristics, functional properties, and safety of dairy products. Moreover, since dairy products are one of the highest consumed products in the globe, the dispatch channels for fermented dairy products are already established. Therefore, incorporating novel probiotic strains into fermented dairy products might be the most feasible approach for their delivery. In this context, our aim is to discuss the feasibility of dairy products as delivery vehicles for novel probiotic strains. Thus, we summarize the scientific evidence that points to a dynamic future for the production of fermented dairy-based probiotics.

Probiotic Properties and Antioxidant Activities of Pediococcus pentosaceus SC28 and Levilactobacillus brevis KU15151 in Fermented Black Gamju

Black gamju is Korean traditional beverage fermented with molds. The aim of this study was to assess the probiotic properties and antioxidant activities of novel Pediococcus pentosaceus SC28 and Levilactobacillus brevis KU15151 to develop black gamju with bioactive properties for health. Tolerance against artificial gastric juice and bile salts, adhesion ability on HT-29 cells of strains, and antibiotics susceptibility were evaluated as probiotics, and various enzyme productions were detected. The 2,2-diphenyl-1-picrylhydrazyl assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate, and β-carotene bleaching assay were used for antioxidant activity of samples. The tolerance of both strains to artificial gastric juice and bile salts (Oxgall) was more than 90%. Additionally, both strains did not produce β-glucuronidase and were resistant to gentamicin, kanamycin, streptomycin, and ciprofloxacin. After fermentation of black gamju with each strain, the number of viable lactic acid bacteria increased to 8.25-8.95 log colony forming unit/mL, but the pH value of fermented samples decreased more (to pH 3.33-3.41) than that of control (pH 4.37). L. brevis KU15151 showed higher adhesion activity to HT-29 cells and antioxidant effects than P. pentosaceus SC28 in three antioxidant assays.

Antioxidant and Anti-Inflammatory Effect of Probiotic Lactobacillus plantarum KU15149 Derived from Korean Homemade Diced-Radish Kimchi

Lactobacillus plantarum KU15149 was demonstrated to have probiotic behavior and functions, including antioxidant and anti-inflammatory activity. L. plantarum KU15149 obtained from homemade diced-radish kimchi has a high survival rate under artificial gastric acid (pH 2.5, 0.3% pepsin) and bile salt (0.3% oxgall) conditions. However, L. plantarum KU15149 did not produce β-glucuronidase, which is known to be a carcinogenic enzyme with resistance to several antibiotics, such as gentamycin, kanamycin, streptomycin, tetracycline, and ciprofloxacin. L. plantarum KU15149 strongly adhered to HT-29 cells and had high antioxidant activity in terms of 2,2-diphenyl- 1-picrylhydrazyl (DPPH) free radical-scavenging and β-carotene bleaching assays. L. plantarum KU15149 also exhibited a pronounced inhibition of nitric oxide (NO) production, along with expression of nitric oxide synthase (iNOS) and cyclooxygenase -2 (COX-2) as well as proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6, when RAW 264.7 cells were stimulated with LPS. Therefore, L. plantarum KU15149 exhibited pharmaceutical functionality as a potential probiotic.

Probiotic characterization of Lactobacillus brevis KU15153 showing antimicrobial and antioxidant effect isolated from kimchi

Lactobacillus brevis KU15153 was isolated from kimchi and probiotic characterization was performed including analysis of its antimicrobial and antioxidant effects. Lactobacillus rhamnosus GG (LGG) was used as a probiotic control. L. brevis KU15153 survived under artificial gastric conditions and was non-hemolytic, showed antibiotic susceptibility, and did not produce carcinogenic β-glucuronidase. L. brevis KU15153 adhered strongly to HT-29 cells in the direct adherent assay and showed high cell surface hydrophobicity. Particularly, L. brevis KU15153 showed antimicrobial activity against the food-borne pathogens Escherichia coli ATCC 25922, Listeria monocytogenes ATCC 15313, Salmonella Typhimurium P99, and Staphylococcus aureus KCCM 11335. Antioxidant activity was assessed using the DPPH radical scavenging assay and β-carotene and linoleic acid inhibition assay. L. brevis KU15153 showed higher antioxidant activity than LGG. These results suggest that L. brevis KU15153 has potential for use as a probiotic organism.

Characterization of cottage cheese using Weissella cibaria D30: Physicochemical, antioxidant, and antilisterial properties

This study aimed to evaluate the potential of Weissella cibaria D30 as an adjunct culture in cottage cheese, including an assessment of antioxidant, antilisterial, and compositional parameters. Cottage cheese samples were manufactured using a commercial starter culture and probiotic strains Lactobacillus rhamnosus GG (GG) or W. cibaria D30 (W) and without probiotic (control). Samples were stored at 4 ± 1°C for 28 d. Bacterial cell counts (log cfu/g) of control, GG, and W samples were counted at 0, 7, 14, 21, and 28 d. Counts of W. cibaria D30 in the W samples remained at 6.85 log cfu/g after 28 d. Total solids, fat, protein, ash, and pH were measured and no significant differences were observed in compositional parameters or pH after 28 d of storage in all cheeses except those inoculated to Listeria monocytogenes. To measure the antilisterial effect, Listeria monocytogenes was inoculated into the cottage cheese samples and bacterial cell counts were obtained at 0, 6, 12, 24, 48, 72, 96, 120, and 144 h. Listeria monocytogenes counts were less than the analytical limit of detection (<10 cfu/g) in the inoculated GG and W samples, whereas the counts of L. monocytogenes in the inoculated control sample remained at 3.0 log cfu/g after 144 h. We used the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activity assays to assess antioxidant activity: GG and W samples exhibited significant increases in antioxidant activity compared with the control sample. These results indicate that W. cibaria D30 has potential as an adjunct culture in the dairy industry.

Antioxidant and immune-enhancing effects of probiotic Lactobacillus plantarum 200655 isolated from kimchi

Probiotic properties including antioxidant and immune-enhancing effects of Lactobacillus plantarum 200655 isolated from kimchi were evaluated. The tolerance of three strains (L. plantarum 200655, L. plantarum KCTC 3108, and L. rhamnosus GG to bile salts (0.3% oxgall, 24 h) was similar, and L. plantarum 200655 showed the highest tolerance to gastric juice (0.3% pepsin, 3 h). All strains presented similar autoaggregation ability. L. plantarum 200655 showed higher cell surface hydrophobicity and adhesion ability on HT-29 cells. L. plantarum 200655 did not produce β-glucuronidase and was sensitive to ampicillin, tetracycline, chloramphenicol, and doxycycline. Additionally, L. plantarum 200655 showed the highest antioxidant effects in DPPH and ABTS radical scavenging, and β-carotene bleaching assays. RAW 264.7 cells treated with L. plantarum 200655 produced more nitric oxide, induced nitric oxide synthase, and cytokine related to immune-enhancing effects such as interleukin-1β and interleukin-6. Therefore, L. plantarum 200655 could be useful as a probiotic strain for older people.

Antioxidant effects of live and heat-killed probiotic Lactobacillus plantarum Ln1 isolated from kimchi

The aim of this study was to evaluate the probiotic properties of Lactobacillus plantarum Ln1 isolated from kimchi and the antioxidant activities of live and heat-killed cells. L. plantarum KCTC 3108, which has been used as a commercial probiotic strain, was used as a control. L. plantarum strains (Ln1 and KCTC 3108) can survive under artificial gastric conditions (pH 2.5 in 0.3% pepsin for 3 h and 0.3% oxgall for 24 h), and adhere strongly to HT-29 cells. In addition, L. plantarum Ln1 did not produce carcinogenic β-glucuronidase, whereas it showed a higher β-galactosidase production of 3067.42 mU/mL. The antioxidant activity of L. plantarum Ln1 was assessed using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, β-carotene and linoleic acid inhibition, and reducing power assays. In all these methods, live L. plantarum Ln1 showed a higher antioxidant activity than the control strain. In heat-killed cells of L. plantarum Ln1, β-carotene bleaching inhibitory activity and reducing power was higher than DPPH and ABTS radical scavenging activity. These results suggested that live or heat-killed L. plantarum Ln1 isolated from kimchi might be useful as an antioxidant probiotic.

Probiotic white cheese production using coculture with Lactobacillus species isolated from traditional cheeses

Aim:

The aim of the present study was to investigate the viability of lactic acid bacteria isolated from traditional cheeses and cocultured in Iranian white cheese during ripening.

Materials and Methods:

A total of 24 samples were isolated from 8 types of traditional cheeses in West Azerbaijan, Iran. Isolated species were cocultured with starter bacteria during the production of Iranian white cheese, and their viability was investigated up to 60 days of the refrigerated storage.

Results:

Of 118 isolates of Lactobacillus, 73 isolates (62%) were confirmed as facultative heterofermentative and 45 isolates (38%) as obligate homofermentative. Of the facultative heterofermentatives, 28 isolates (24%) were Lactobacillus plantarum, 24 isolates (20%) were Lactobacillus casei, and 21 isolates (18%) were Lactobacillus agilis. Obligate homofermentatives were Lactobacillus delbrueckii (21%), Lactobacillus helveticus (14%), and Lactobacillus salivarius (3%). L. plantarum, L. casei and L. helveticus were found in high enough levels(10⁶ CFU/g).

Conclusion:

According to the obtained data, it is recommended that complex starters such as L. helveticus, L. plantarum, and L. casei can be used in industrial productions of cheese to obtain exclusive properties of traditional cheeses.

Probiotic lactic acid bacteria isolated from traditional Korean fermented foods based on β-glucosidase activity

This study was designed to isolate lactic acid bacteria (LAB) with β-glucosidase activity and probiotic properties from Korean fermented foods. Among nine isolates, four LAB strains had excellent survival rates at pH 2.5 with 0.3% (w/v) pepsin for 3 h and 0.3% (w/v) oxgall for 24 h. Four LAB strains did not produce β-glucuronidase and showed adhesion ability to HT-29 cells that was superior to that shown by the reference strain Lactobacillus rhamnosus GG. All four strains were sensitive to ampicillin, tetracycline, chloramphenicol, and doxycycline. These strains were identified as Leuconostoc mesenteroides H40, Lactobacillus plantarum FI10604, L. brevis FI10700, and L. perolens FI10842 by 16S rRNA gene sequence, respectively. It was found that L. perolens FI10842 produced the highest β-glucosidase activity (49.10 mU/mL). These results indicate that the four LAB strains could be used as potential probiotic. Especially L. perolens FI10842 could be used as a starter culture for fermentation.

Probiotic characterization of Bacillus subtilis P223 isolated from kimchi

Probiotic characteristics of Bacillus subtilis P223 isolated from kimchi were investigated in this study. Spore cells of B. subtilis P223 showed high tolerance to artificial gastric juice (pH 2.5, 0.3% pepsin, 3 h) and bile salts (0.3% oxgall, 24 h). Spore cells of B. subtilis P223 showed more adherence to intestinal cells (HT-29 cells) than vegetative cells. In addition, B. subtilis P223 showed high autoaggregation ability, similar to a commercial strain (Bacillus clausii ATCC 700160). Moreover, its coaggregation abilities with pathogens were strong. The adherence of three pathogens (Salmonella enteritidis ATCC 13076, Listeria monocytogenes ATCC 15313, and Escherichia coli ATCC 25922) to HT-29 cells was inhibited by B. subtilis P223. It was found that B. subtilis P223 could not produce β-glucuronidase, a carcinogenic enzyme. However, it had amylase and protease activities. Antibiotic susceptibility was measured using disk diffusion assay. It was revealed that B. subtilis P223 was only resistant to streptomycin among eight kinds of antibiotics. In addition, B. subtilis P223 showed no hemolysis activity. It did not have enterotoxin genes. Results of this study suggest that B. subtilis P223 isolated from kimchi has potential as a probiotic strain.