Probiotic characterization of <Emphasis Type="Italic">Bacillus subtilis</Emphasis> 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.     

Estrogenic effects of various extracts from <Emphasis Type="Italic">Chamdanggui</Emphasis> (<Emphasis Type="Italic">Angelica gigas</Emphasis> Nakai) and <Emphasis Type="Italic">sogdan</Emphasis> (<Emphasis Type="Italic">Phlomis umbrosa</Emphasis> Turcz)

The various extracts from chamdanggui (Angelica gigas Nakai) and sogdan (Phlomis umbrosa Turcz) were evaluated for estrogenic activity and characterized according to HPLC profile. Chamdanggui and sogdan were individually extracted with 4 solvents (hot water, 70% ethanol, n-butanol, and dichloromethane) of differing polarities. Estrogenic activity was determined by E-screen using an estrogen-dependent MCF-7 BUS cell. Although almost all extracts showed estrogenic effects in a concentrationdependent manner, the hot water extract from chamdanggui (250 μg/mL) had the higher effect (138%). Among 90 fractions using HPLC separation of the hot water extract from chamdanggui, fraction 21 and 28 produced the highest estrogenic effects of 178 and 163% at 10 μg/mL, respectively. The results imply that the hot water extract from chamdanggui could be useful as an alternative hormone replacement therapy.     

Differences of Bactericidal Efficacy on <Emphasis Type="Italic">Escherichia coli</Emphasis>, <Emphasis Type="Italic">Staphylococcus aureus</Emphasis>, and <Emphasis Type="Italic">Bacillus subtilis</Emphasis> of Slightly and Strongly Acidic Electrolyzed Water

In the present study, the disinfection efficacy of slightly acidic electrolyzed water (SAEW) and strongly acidic electrolyzed water (AEW) was tested on three bacteria, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis and the disinfection mechanism was discussed. The results showed that SAEW had a stronger antibacterial efficacy against these tested bacteria in comparison with AEW. The results also showed that both SAEW and AEW treatments could damage the cell membrane, which was demonstrated microcosmically by scanning electron microscopy (SEM), thus causing leakages of protein, DNA, RNA, and ATP, resulting in the death of microbes. Moreover, AEW treatment could not cause the degradations of DNA and RNA, and nucleic acids including DNA and RNA are not the target point of its bactericidal efficacy. However, SAEW could maybe cause the degradation of RNA, and RNA may be the target in its antibacterial activity. We suggested that the differences in antibacterial efficacy between SAEW and AEW could be explained by the different impacts on RNA of tested strains.     

Molecular diversity among natural populations of <Emphasis Type="Italic">Lactobacillus paracasei</Emphasis> and <Emphasis Type="Italic">Lactobacillus plantarum</Emphasis>/<Emphasis Type="Italic">paraplantarum</Emphasis> strains isolated from autochthonous dairy products

The diversity of 87 Lactobacillus paracasei and Lactobacillus plantarum/paraplantarum strains, previously identified from different autochthonous dairy products, was investigated by phenotypic and genotypic approaches. The increased resolution obtained using phenotypic and genotypic characterization allowed the level of strain heterogeneity detection to be widened. Phenotypic diversity was evaluated by studying biochemical characteristics of technological interest, including antimicrobial and proteinase activities, resistance to nisin, aggregation ability, production of exopolysaccharides, acetoin and diacetyl, citrate utilization, and antibiotic susceptibility. Genotypic diversity was generally evaluated by PCR amplification of repetitive bacterial DNA element fingerprinting using the (GTG)₅ primer [(GTG)₅-PCR]. Moreover, in cases where strains were not discriminated by (GTG)₅-PCR combined with phenotypic analysis, pulsed-field gel electrophoresis (PFGE) analysis was performed. The results indicate that L. plantarum/paraplantarum and L. paracasei natural isolates from artisanal dairy products are a gold mine in terms of diversity of strains and could be potentially interesting to dairy companies for the formulation of functional starter cultures in the production of innovative foods.     

Characterization of brewing microorganisms isolated from Korean traditional <Emphasis Type="Italic">nuruk</Emphasis> for <Emphasis Type="Italic">Cheongju</Emphasis> production

The objective of this study was to select and identify yeasts and molds isolated from traditional nuruk and to investigate their brewing characteristics for Cheongju production. The yeast strains Y190 (Accession ID-KACC 93251P), Y263 (Accession ID-KACC 93252P), and Y270 (Accession ID-KACC 93253P) showing high alcohol and flavor productivity were isolated and identified by phylogenetic inference based on an internal transcribed spacer 2 region sequence analysis. In addition, Aspergillus oryzae 83-10 (Accession ID-KACC 93254P) showing the highest enzyme activity was isolated. This study provides basic data for the production of Korean Cheongju and assesses the applicability of these three yeast strains and A. oryzae 83-10 isolated from traditional nuruk.     

Prevalence,genetic diversity,and antibiotic susceptibility of <Emphasis Type="Italic">Cronobacter</Emphasis> spp. (<Emphasis Type="Italic">Enterobacter sakazakii</Emphasis>) isolated from <Emphasis Type="Italic">Sunshik</Emphasis>, its ingredients and soils

The prevalence, genetic diversity, and antibiotic susceptibility of Cronobacter species (Enterobacter sakazakii) isolated from sunshik products, its ingredients, and root vegetable farm’s soils were investigated to analyze main reservoirs and contaminated sources of Cronobacter spp. Cronobacter spp. was isolated from 9 of 15 sunshik products, 26 of 72 its ingredients, and 2 of 39 soils. The root vegetables such as sweet potato and carrot showed higher contamination rate (70%) than the other sunshik ingredients. All isolates showed 929 bp band amplified from 16S rRNA and resistant to ampicillin, amoxicillin/clavulanic acid, and cefazolin. All isolates showed diverse random-amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) band patterns. However, 3 cases of RAPD banding patterns between clinical strains and isolates from sunshik products and root vegetables (yam, carrot) were related with similarities level of 80%. These studies indicated that root vegetables can be an important contamination source of Cronobacter spp. in sunshik products. Thus, the preparation of root vegetables for manufacturing sunshik products used as a weaning diet was handled with more care than the other sunshik ingredients.     

Tyramine production of technological important strains of <Emphasis Type="Italic">Lactobacillus</Emphasis>, <Emphasis Type="Italic">Lactococcus</Emphasis> and <Emphasis Type="Italic">Streptococcus</Emphasis>

The aim of this paper was to study the biogenic amines (histamine, tyramine, putrescine, cadaverine, agmatine, spermine and spermidine) production of selected technological important lactic acid bacteria (strains of the genera Lactococcus, Lactobacillus and Streptococcus). Three methods (ion-exchange chromatography (IEC), PCR and cultivation method with pH indicator) were used. Within the 39 strains of lactic acid bacteria tested, the production of tyramine (formed by tyrosine decarboxylase) was detected in eight strains (3 strains of Lactococcus lactis subsp. lactis, three strains of Lactococcus lactis subsp. cremoris, 1 strain of Streptococcus thermophilus and 1 strain of Lactobacillus delbrueckii subsp. bulgaricus). The other tested biogenic amines were not detected. Cultivation in decarboxylation broth seems to be the least accurate method for the detection of biogenic amines due to enhanced risk of false-positive reactions. Therefore, in order to detect bacteria producing biogenic amines, the combination of PCR and chromatographic methods (e.g. IEC) can be recommended.     

Characterization of new oligosaccharide converted from cellobiose by novel strain of <Emphasis Type="Italic">Bacillus subtilis</Emphasis>

Six bacterial strains isolated from various Korean fermented foods were cultured in cellobiose-containing medium to investigate their potential for producing new kind of oligosaccharides. After bacterial culture in a liquid medium, each culture medium was concentrated and analyzed. TLC analysis revealed that only one strain (Bacillus subtilis SS-76) produced new spot on the TLC plate, indicating that it could converts cellobiose into a new oligosaccharide. Following purification of the culture supernatant of B. subtilis SS-76, the fractions containing the oligosaccharide produced were pooled, and the concentrated fraction was analyzed for its chemical and structural characteristics. By using various analytical techniques such as sugar composition analysis, glycosidic linkage analysis, and molecular weight determination, the new oligosaccharide was identified as glucotriose connected with (1 → 4) and (1 → 3) glycosidic linkages. In addition, the result of specific enzyme catalysis suggested that the new glucotriose might contain only β-configurations in their anomeric configurations.     

Molecular diagnostics of Lemon Myrtle (<Emphasis Type="Italic">Backhousia citriodora</Emphasis> versus <Emphasis Type="Italic">Leptospermum citratum</Emphasis>)

‘Lemon Myrtle’ is becoming increasingly popular in Europe both for use in cuisine and phytotherapy. However, this common name covers two completely different species, Backhousia citriodora F. Muell. and Leptospermum citratum Challinor, Cheel & A.R.Penfold. These species differ with respect to secondary compounds and even can cause, if mixed up and applied in high dose, toxic effects. We describe how the two species can be discriminated microscopically making use of differences in the morphology of leaf pavement cells and the relative size of palisade parenchyma. Based on the large subunit of ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL) as molecular marker, the phylogenetic position of the two species within the Myrtaceae could be clarified. This sequence information was used to develop a simple assay to discriminate the two species even in dried and highly fragmented mixtures as typically occurring in commercial samples. This assay utilises the occurrence of single-nucleotide exchanges between those species that produce different fragments when the rbcL amplificates are restricted with Sac II.     

Phenolic contents and antioxidant activities from different tissues of <Emphasis Type="Italic">Baekseohyang</Emphasis> (<Emphasis Type="Italic">Daphne kiusiana</Emphasis>)

The aim of this research was to investigate the levels of phenolic compounds and antioxidant activities in different tissues including leaves, stems, and roots from baekseohyang (Daphne kiusiana). The highest contents of total phenolics (43.59 mg gallic acid equivalent, GAE/g) and flavonoids (15.73 mg rutin equivalents, RE/g) were observed in the 75% methanol extract of leaves. Moreover, this extract had the predominant antioxidant capacity, DPPH (85.91%) and ABTS (92.57%) radical scavenging activities as well as reducing power (7.20%) at a concentration of 5 mg/mL. The highest content of phenolic compounds was also exhibited in this extract with an increasing order in leaves, roots, and stems and their major components were vanillic acid (6.37 mg/g), tannic acid (1.91 mg/g), and p-hydroxybenzoic acid (3.96 mg/g). Thus, the strong antioxidant activities of the 75% methanol extract are correlated with high phenolic compound contents. This study suggests that baekseohyang leaves may potentially be used as an accessible source of natural antioxidants.     

Heavy metal contents and chemical compositions of atlantic (<Emphasis Type="Italic">Scomber scombrus</Emphasis>), blue (<Emphasis Type="Italic">Scomber australasicus</Emphasis>), and chub (<Emphasis Type="Italic">Scomber japonicus</Emphasis>) mackerel muscles

The heavy metal contents and chemical compositions among mackerel species were investigated. Atlantic and chub mackerel had higher mercury, but lower lead than blue mackerel. Chub mackerel had the highest crude fat (18.62%) and the lowest moisture (58.29%), whereas blue mackerel had the highest moisture (70.10%) and the lowest crude fat (2.89%). Atlantic and blue mackerel had total saturated fatty acids (SFA)>polyunsaturated fatty acids (PUFA)>monounsaturated fatty acids (MUFA), whereas chub mackerel had PUFA>SFA>MUFA. The main SFA of the 3 mackerels were 16:0 and the main PUFAs were 22:6n-3 and 20:5n-3. The total amino acid contents in Atlantic, blue, and chub mackerel were 190.63, 169.49, and 172.97 mg/g, respectively. The major amino acids of the 3 mackerels were glutamic acid, aspartic acid, lysine, and leucine.     

In vivo study of antiallergenicity of ethanol extracts from <Emphasis Type="Italic">Sargassum tenerrimum</Emphasis>, <Emphasis Type="Italic">Sargassum cervicorne</Emphasis> and <Emphasis Type="Italic">Sargassum graminifolium turn</Emphasis>

Food allergy has becoming the serious threat in the world for which the search of an effective anti-allergic drug is the demand of time. Keeping in view of the potentiality of seaweeds, the ethanol extracts from Sargassum tenerrimum (ST), Sargassum cervicorne (SC), and Sargassum graminifolium turn (SG) have been studied in vivo for its antiallergenicity through passive cutaneous anaphylaxis (PCA) and active cutaneous anaphylaxis (ACA) in female BALB/c mice. Intraperitoneal administration of these ethanol extracts inhibit mouse PCA and ACA in a dose-dependent manner using ovalbumin (OVA) and shrimp allergen as triggering agents to induce allergenicity over mice. The extract of ST containing phlorotannin has been found most active over the suppression of PCA triggered by OVA and shrimp with IC₅₀ values of 25.64 and 40.98 mg/kg, respectively and an efficacy comparable to that of an anti-allergic drug disodiumcromoglycate. Similarly, ST inhibits ACA triggered by ova and shrimp allergen in the mouse, with 50% suppression at 25.5 and 43.53 mg/kg, respectively. The results presented here show that these extracts are active on the studied models among which ethanol extract of ST was the most potent, leading toward the promising development of a new class of anti-allergic drugs.     

A New Multiplexed Real-Time PCR Assay to Detect <Emphasis Type="Italic">Campylobacter jejuni</Emphasis>, <Emphasis Type="Italic">C. coli</Emphasis>, <Emphasis Type="Italic">C. lari</Emphasis>, and <Emphasis Type="Italic">C. upsaliensis</Emphasis>

A new rapid method based on real-time PCR was developed to detect four thermophilic Campylobacter species (Campylobacter jejuni, Campylobacter coli, Campylobacter lari, and Campylobacter upsaliensis) in food samples. The assay targeted the bipA gene for C. upsaliensis and C. lari, whereas the gene encoding the ATP-binding protein CJE0832 was used to detect C. coli and C. jejuni. These genes were chosen for this assay due to their low variability and mutation rate at a species level. The multiplex PCR showed 100% inclusivity for all 25 thermophilic Campylobacter strains tested and 100% exclusivity for 38 non-targeted strains belonging to closely related species. The newly developed real-time PCR could detect down to 10² genomes/reaction and displayed efficiency above 97% for all species except for C. upsaliensis (90.1%). The method proved to be a reliable tool for food analysis, showing 100% sensitivity, 96% efficiency, and 92.45% specificity when validated against the gold standard method UNE-EN ISO 10272:2006 using 200 diverse food samples (meat, fish, fruits and vegetables, and raw milk). In artificially spiked samples, the detection limit of the method was 10 cfu/g in salad, 5 cfu/g in turkey meat, and 1 cfu/g in the rest of meat samples tested. Consequently, the newly designed molecular tool represents a quick and safe alternative to obtain reliable results concerning the presence/absence of the main thermophilic Campylobacter in any food sample.     

Antitumor activities of liposome-incorporated aqueous extracts of <Emphasis Type="Italic">Anodonta </Emphasis><Emphasis Type="Italic">woodiana</Emphasis> (Lea, 1834)

To acquire the effectiveness of oral treatments, aqueous extracts of Anodonta woodiana (HB) were incorporated into liposome and its antitumor activities evaluated in vivo. The HB-loaded liposomes (HBL) were prepared at a mean size of 14.85 μm by reverse-phase evaporation method. Referring to the maximum tolerated doses test, mice with orally administrated HBL, at a 3 g/kg body weight dosage, showed no obvious acute toxic sign. Furthermore, the tumoricidal activities of HBL against C26 murine colon carcinoma, Lewis lung tumor, human QGY hepatic carcinoma and MKN-45 gastric tumor were examined, respectively. In contrast to free HB, HBL possessed remarkable antitumor activity. Simultaneously, the effect of HBL was observed in a dose-dependent manner. For C26 murine colon carcinoma and Lewis lung tumor, the inhibitory ratios of HBL were 54.36 and 51.97% at a dose of 400 mg/kg, respectively. The suppression of tumor growth and the reduction in body weight were more pronounced in human QGY hepatic carcinoma and MKN-45 gastric tumors inoculated mice by treatment of HBL during 30 days. All these promising results implied that liposome-incorporated aqueous extracts of Anodonta woodiana had a more potential application as a natural antitumor and immunomodulator formulation.     

Production and characterization of milk-clotting enzyme from <Emphasis Type="Italic">Bacillus amyloliquefaciens</Emphasis> JNU002 by submerged fermentation

Milk-clotting enzymes produced by microorganisms have been developed to replace calf rennet, yet the enzymatic level and the ratio of milk-clotting activity to proteolytic activity still need further improvement. This work described a strain Bacillus amyloliquefaciens JNU002 that screened from wheat bran that has a promising characterization. After optimization, B. amyloliquefaciens JNU002 showed a high milk-clotting activity (4969 SU/mL) and low proteolytic activity (4.02 U/mL) at 48 h with an inoculum size of 0.2% (v/v) at initial pH 6.0 in 15-L bioreactor. After purification, the purified enzyme gave a single protein band on SDS–PAGE, corresponding to 28 kDa. The purified enzyme showed a high ratio (2,575) of milk-clotting activity to proteolytic activity at 35 °C, and the ratio would be even higher (22,992) at 70 °C. The milk-clotting reaction and proteolytic reaction were prevented at 75 °C. This enzyme was stable at pH 4–6 and below 40 °C, and this was convenient for storage and transportation.     

Zusammensetzung der Muskulatur unbehandelter Pangasien (<Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis>) und Zander (<Emphasis Type="Italic">Sander lucioperca</Emphasis>)

We investigated the composition of muscle tissue from 30 untreated striped catfish (Pangasianodon hypophthalmus) and 40 untreated pikeperch (Sander lucioperca). The analyzed fillets had a mean moisture level of 77.5 % in striped catfish and 78.7 % in pikeperch. The mean level of protein content was 19 % in striped catfish and 20.5 % in pikeperch; the pH was 6.5 in striped catfish and 6.8 in pikeperch. Our data provide a first basis on a legal opinion concerning fishery products that are suspected to contain high amounts of added water. These data can also be used for the calculation of added water regarding the regulation of the European Union (EU) No 1169/2011, provision of food information to consumers.     

Thermal inactivation kinetics of quality-related enzymes in cauliflower (<Emphasis Type="Italic">Brassica oleracea</Emphasis> var. <Emphasis Type="Italic">botrytis</Emphasis><Emphasis Type="Bold">)</Emphasis>

Thermal inactivation of quality-related enzymes in both cauliflower crude enzyme extracts and fresh tissue samples was studied in temperature range 50–100 °C. For crude enzyme extracts, several parameters, reaction rate constants (k) and activation energy (E _a) as well as decimal reduction time (D) and (z) values, were used to characterize the thermal stability. The rates of inactivation were found to follow first-order inactivation kinetics. Activation energies varied between 101.18 and 208.42 kJ mol⁻¹ with z values of 10.59–24.09 °C. The examined kinetics indicated that lipoxygenase was the most heat resistant followed by peroxidase, polyphenol oxidase, pectin methyl esterase and ascorbic acid oxidase. Furthermore, the obtained results from the blanched fresh tissues indicated that inactivation of lipoxygenase secured disappearing of any other enzyme activities. Therefore, this study recommends using lipoxygenase as an indicator enzyme to optimize the thermal treatments of cauliflower products.     

Antioxidant and emulsion properties of freshwater carps (<Emphasis Type="Italic">Catla catla</Emphasis>, <Emphasis Type="Italic">Labeo rohita</Emphasis>, <Emphasis Type="Italic">Cirrhinus mrigala</Emphasis>) protein hydrolysates prepared using flavorzyme

Fish protein hydrolysates (FPHs) were prepared from freshwater carps (Catla catla, Labeo rohita, and Cirrhinus mrigala) using flavorzyme at different degrees of hydrolysis (DHs) ranging from 5 to 20%. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of the FPHs prepared from the three species were in the range of 50–82%; the ferric reducing power of the FPHs prepared from catla was the highest. The linoleic acid peroxidation inhibition activity of the prepared FPHs varied from 71 to 91%. The emulsion activity index of the FPHs prepared from catla and rohu decreased significantly with an increase in the DH (p < 0.05). The emulsion stability index of the FPHs prepared from the three species was the highest at 20% DH. FPHs prepared from freshwater carps possess good antioxidant and surface-active properties and are therefore suitable to be used as natural antioxidants in health-food formulation and as water-soluble antioxidants in the food-processing industry.     

Effect of glasswort (<Emphasis Type="Italic">Salicornia herbacea</Emphasis> L.) and rice (<Emphasis Type="Italic">oryza sativa</Emphasis> L.) on quality of <Emphasis Type="Italic">Ganjang</Emphasis> (Korean Soy Sauce)

Four types of meju were made from 100%(w/w) defatted soybean (DFS), a mixture of 80%(w/w) defatted soybean, and 20%(w/w) glasswort (DFS-G), a mixture of 80%(w/w) defatted soybean and 20%(w/w) rice (DFS-R), and a mixture of 60%(w/w) defatted soybean, 20%(w/w) glasswort, and 20%(w/w) rice (DFS-GR). Four types of Korean traditional soy sauce were prepared from the 4 types of meju. Mineral and antioxidant contents in the soy sauce made of DFS-G and DFS-GR were significantly higher than others. Citric, malic, succinic, lactic, and pyroglutamic acid contents in soy sauce made of DFS-R and DFS-GR were 1.3–1.5 times higher than others. Total nitrogen and free amino acid contents in soy sauce were correlated with DFS concentration in the meju. The bacterial community in the non-fermented meju-making ingredients was replaced largely by Bacillus sp. in the fermented meju. The use of glasswort and rice in the meju-making process did not alter the bacterial community responsible for the fermentation of meju.     

Xanthan gum production under different operational conditions by <Emphasis Type="Italic">Xanthomonas axonopodis</Emphasis> pv <Emphasis Type="Italic">vesicatoria</Emphasis> isolated from pepper plant

The influence of operational conditions (pH, stirrer speed, and temperature) used in the process of xanthan production by Xanthomonas axonopodis pv vesicatoria (XCVA3-1) isolated from pepper plant were evaluated through yield of xanthan and compared with control strain Xanthomonas campestris NRRL-B 1459. Different conditions used during the fermentation affected the xanthan production. In this study the best combination of yield was obtained, reaching 1.325 g/100 mL with the use of pH 7.0, 30°C, and 250 rpm during fermentation. Increased yield of xanthan production can be obtained at high agitation values, with the maximum at 400 rpm. Higher yields of gum production can be obtained at 30°C and the optimum pH was found 7.0. This results were similar for the X. campestris NRRL-B 1459.