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The presence of unwanted competing flora has been the most common confounding factor in the enumeration of Bacillus cereus (B. cereus) using selective media such as mannitol-yolk-polymyxin B agar (MYPA). The objective of this study was to improve MYPA selectivity for B. cereus by supplementation with a second-generation cephalosporin, cefuroxime. The performance of cefuroxime-supplemented MYPA (cefu-MYPA) was evaluated by comparison with original MYPA in 60 food products with established microbiological standards for B. cereus contamination. Cefu-MYPA demonstrated superior recoverability and selectivity for B. cereus compared with original MYPA in most tested foods. B. cereus numbers on MYPA and cefu-MYPA were 363.5 and 462.0 CFU/g, respectively. Competing flora on cefu-MYPA was detected in significantly less samples (70%) compared to original MYPA (93%). In addition, the detection and isolation of suspected colonies were significantly improved in cefu-MYPA because of the reduction or elimination of competing flora in all tested foods except fruit juice, indicating superior selectivity of the modified medium. Our findings suggest that cefuroxime supplementation of MYPA would markedly improve the detection rate of B. cereus, particularly in foods with high levels of indigenous flora.

Bombyx mori (silkworm pupae) is a unique and biologically significant insect, which is a recognized source of high quality protein that provides all the essential amino acids required for human health. Recently, many studies have focused on various biomedical applications of B. mori proteins. The purpose of this study was to manufacture protein-fortified kefir containing different concentrations of B. mori powder according to pH and sensory evalua-tions. The value of the protein-fortified kefir increased but the pH decreased with increasing incubation time, indicating that the amount of B. mori powder did not affect and pH. Addition of B. mori powder also did not affect the sensory properties of overall acceptability, texture, and color compared to control group without addition of B. mori powder. However, flavor and taste were affected by increasing the amounts of B. mori powder, with a significant difference in both flavor and taste between the control and treated groups (both p

Exponential growth of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in Campylobacter media has become a common problem for the detection of Campylobacter in chicken meats. We investigated the minimum inhibitory concentration of 40 ESBL-producing E. coli isolates from meats obtained from various countries against antibacterial agents in Bolton broth (cefoperazone, vancomycin, and trimethoprim). All ESBL-producing E. coli strains were resistant to cefoperazone and vancomycin, whereas 50% of them were resistant to trimethoprim and grew in Bolton broth. We found that 20 μg/mL of rifampicin inhibited the growth of trimethoprim-resistant E. coli strains. Hence, we added 20 μg/mL of rifampicin to Bolton broth to improve the isolation of Campylobacter from chicken carcass rinses. The isolation rate of Campylobacter was significantly higher in the modified broth (44 out of 58, 75.9%, P < 0.05) than in the normal broth (0 out of 58, 0%). Furthermore, the number of agar plates with non-Campylobacter spp. was much lower after enrichment in the modified broth (4 out of 58, 6.9%, P < 0.05) than in the normal broth (58 out of 58, 100%).

We investigated the efficacy of syringe filtration for selective isolation of Campylobacter from chicken carcass rinse by combining syringe filtration with the conventional culture method. Whole chicken carcass rinses were incubated in Bolton enrichment broth, set aside or subjected to syringe filtration, and streaked on Campy-Cefex agar with or without cefoperazone antibiotic supplement. Compared with the conventional method without filtration, 0.65-μm-pore-size syringe filtration resulted in a significantly higher number of Campylobacter-positive samples (23.8 to 37.5% versus 70.0 to 72.5%; P0.05), a lower number of plates contaminated with non-Campylobacter (93.8% versus 6.3 to 26.3%), and a lower growth index (1 = growth of a few colonies; 2 = growth of colonies on about half of the plate; and 3 = growth on most of the plate) for competing microbiota (2.9 to 3.0 versus 1.2 to 1.4). When syringe filtration was applied, agar plates containing the antibiotic had significantly less contamination (6.3% versus 26.3%; P0.05) and a lower growth index (1.2 versus 1.4) compared with plates without the antibiotic, although the Campylobacter isolation rate was similar (P0.05). Syringe filtration combined with conventional enrichment improved the rate and selectivity of Campylobacter isolation from chicken carcasses.

Made using a natural mixed starter of lactic acid bacteria and yeast, Koumiss is a slightly alcoholic fermented mare`s milk beverage, and a traditional drink of the nomadic populations of Central Asia. Cichorium intybus L. (chicory) is a sedative with potential cardioactive pro-perties, and its oligosaccharides are beneficial in maintaining healthy gastrointestinal flora. Hence, in this study, we have generated a functional Koumiss containing two different concen-trations of chicory. After fermentation of the Koumiss premix, the TA increased to 0.85~ 0.88%, and the pH decreased to ~4.3. The addition of either concentration of chicory had no significant effect on pH and TA. However, the taste, flavor, color, texture, and overall accept-ability decreased in proportion to the added amount of chicory. This study has provided the first data on Koumiss supplemented with chicory. The results could be useful in developing high-quality Koumiss with functional activity using chicory, and allowing large-scale industrial production. Further studies are needed to determine if chicory root extract is beneficial for lifestyle-related diseases.

Cichorium intybus L. (chicory) roots and leaves are widely used in herbal preparations, which have beneficial effects on the stimulation of digestion and metabolism of food ingredients, gastric juice excretion, diuretic action, and bile excretion. Notably, chicory root is well known as a source of polyphenols, compounds with recognized value in health improvement. In this study, we examined the physicochemical characteristics (TA, pH, and sensory evaluation) of bioactive yoghurt containing different concentrations of chicory. With increasing incubation time (5 h), the TA of the yoghurt increased whereas the pH decreased, regardless of the amount of chicory. As the amount of chicory increased, the scores for color, flavor, taste, and overall acceptability generally decreased. Among the tested groups, yoghurt with the addition of 1% chicory attained the highest scores. Further studies on the production of bioactive yogurt with optimum chicory concentration are needed.

The roots of Cichorium intybus L. (chicory) have many nutritional qualities and also have been used for health promotion as traditional medicine. The antimicrobial activity of Cichorium intybus L.`s (chicory) ethanol extract on Bacillus cereus ATCC 10876 were investigated using spot on lawn method in this study. Ethanol extract exhibited antimicrobial activities against Bacillus cereus ATCC 10876 with significance. Also, the results produced the larger zones of inhibition against Bacillus cereus ATCC 10876 tested, with increasing concentration of Cichorium intybus L.`s (chicory) ethanol extracts,. Hence, Cichorium intybus L. (chicory) could be served for keeping the safety of various dairy products as natural antimicrobial agents.

Kaempferia parviflora (Krachaidam, Zingiberaceae) is used as a traditional Thai medicine for treating various ailments, including allergy, fatigue, sexual dysfunction, and ulcer. Moreover, it is also used to promote longevity and as a nerve tonic. The aim of this study was to develop functional yoghurt containing Kaempferia parviflora and to examine the physicochemical characteristics of yoghurt supple-mented with different concentration of K. parviflora. To this end, we examined the pH and sensory evaluation of yoghurt containing K. parviflora. The pH of this yoghurt decreased whereas the TA increased with incubation time (up to 5 h) without altering the amounts of K. parviflora added. In the sensory evaluation, the taste, flavor, color, and overall acceptability decreased in proportion to the amount of K. parviflora added. Among the experimental group, high scores were achieved by yoghurt containing 1% K. parviflora compared with that by the control group. We conclude there is an urgent need for additional research on the production of this multi-functional yogurt (with properties including anti-obesity and anti-inflammatory), using an optimum concentration of K. Parviflora.

Rhizomes of Kaempferia parviflora (Zingiberaceae) have been used in traditional Thai medicine for health promotion. In this study, the antibacterial activity of ethanol extract of K. parviflora against Cronobacter spp. and enterohemorrhagic Escherichia coli (EHEC) was investigated using paper disc dilution method. The results revealed that the ethanol extract exhibited antibacterial activity against Cronobacter spp. and EHEC. With an increasing concentration of K. parviflora ethanol extract, larger zones of inhibition of Cronobacter spp. and EHEC strains tested were observed. Therefore, its antibacterial activity suggested that K. parviflora could be used as a natural additive to ascertain food safety of various dairy products.

Although cefoperazone is the most commonly used antibiotic in Campylobacter-selective media, the distribution of cefoperazone-resistant bacteria such as extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli is increasing. Here we evaluated the potential of cephamycins for use as supplements to improve modified charcoal-cefoperazone-deoxycholate agar (mCCDA) by replacing cefoperazone with the same concentrations (32 mg/L) of cefotetan (modified charcoal-cefotetan-deoxycholate agar, mCCtDA) and cefoxitin (modified charcoal-cefoxitin-deoxycholate agar, mCCxDA). In chicken carcass rinse samples, the number of mCCDA plates detecting for Campylobacter (18/70, 26%) was significantly lower than that of mCCtDA (42/70, 60%) or mCCxDA plates (40/70, 57%). The number of mCCDA plates (70/70, 100%) that were contaminated with non-Campylobacter species was significantly higher than that of mCCtDA (20/70, 29%) or mCCxDA plates (21/70, 30%). The most common competing species identified using mCCDA was ESBL-producing E. coli, while Pseudomonas species frequently appeared on mCCtDA and mCCxDA.

We evaluate the accuracy of whole body muscle mass (WBMM) and appendicular skeletal muscle mass (ASMM) assessed by bioelectrical impedance analysis (BIA) using an InBody770 machine (InBody, Seoul, Korea) referenced to dual-energy X-ray absorptiometry (DXA) in 507 people (mean age 63.7 &plusmn, 10.8 years, body mass index (BMI) 25.2 &plusmn, 3.5 kg/m2). Mean WBMMs measured by BIA and DXA were 49.3 &plusmn, 6.6 kg and 46.8 &plusmn, 6.5 kg in men and 36.1 &plusmn, 4.7 kg and 34.0 &plusmn, 4.8 kg in women, respectively. The respective effect sizes and 95% confidence intervals (CIs) for the difference were 2.49 (2.22&ndash, 2.76) for men, and 2.12 (1.91&ndash, 2.33) for women. Mean ASMMs measured by BIA and DXA were 22.1 &plusmn, 3.3 kg and 19.9 &plusmn, 3.2 kg in men, and 15.3 &plusmn, 2.5 kg and 13.5 &plusmn, 2.2 kg in women, respectively. The respective effect sizes and 95% CIs for the difference were 2.26 (2.10&ndash, 2.41) for men and 1.75 (1.65&ndash, 1.87) for women. The BIA clearly overestimated WBMM by 2.28 kg and ASMM by 1.97 kg compared with DXA. Using BMI, gender, and fat percentage, we derive equations that improved the residuals to &lt, 2 kg between methods from 38.29% to 85.91% for WBMM and 52.78% to 97.02% for ASMM.

Fresh vegetables are a frequent cause of foodborne disease outbreaks because they often do not undergo heat treatment prior to consumption. Pathogenic Escherichia coli strains are the major causative agents of produce-related outbreaks. In this study, we investigated the efficiency of conventional E. coli selective medium, MacConkey (MAC) agar, for the screening of fresh vegetable samples and evaluated the discrimination ability of Levine's eosin methylene blue (L-EMB) agar for E. coli-like colonies obtained from MAC agar. A total of 120 samples of lettuces (n = 60) and radish sprouts (n = 60) were analyzed. Among 17 (14.2%) MAC agar plates containing putative E. coli colonies, only one plate was confirmed E. coli-positive (positive predictive value = 5.9%). All 16 false-positive isolates were identified as Citrobacter braakii and formed E. coli-like colonies on L-EMB agar. These results indicate that in order to reduce false-positive results in screening fresh vegetable samples, both MAC and L-EMB selective agars should be modified with the aim of providing reliable differentiation between E. coli and C. braakii. Practical Applications Although MacConkey (MAC) and Levine's eosin methylene blue (L-EMB) agars are not specific for the detection of pathogenic Escherichia coli, the media are recommended for the isolation of pathogenic E. coli (except E. coli O157:H7) in the Food and Drug Administration Bacteriological Analytical Manual. This is due to the fact that it is difficult to develop each pathogenic strains-specific selective media as they were not classified by their biochemical characteristics. However, the unexpected high prevalence of Citrobacter braakii in fresh vegetables observed in this study indicates that the screening potential of these E. coli selective media needs to be improved.

The emergence of antibiotic-resistant foodborne Salmonella has become a major public health problem. Consumption of undercooked poultry contaminated with Salmonella can induce food poisoning in humans. In this study, we investigated the occurrence and antibiotic resistance patterns of Salmonella spp. isolated from 120 chicken carcasses produced in 6 poultry slaughterhouses in South Korea. A total of 11 samples (9.2%) were found contaminated with Salmonella: 5 isolates were serotyped as Salmonella Bellevue strain (slaughterhouse C) and 6 isolates were serotyped as Salmonella Enteritidis strain (slaughterhouse E). Salmonella Bellevue isolates were resistant to five antibiotics (ampicillin, chloramphenicol, nalidixic acid, tetracycline, and trimethoprim/sulfamethoxazole), while Salmonella Enteritidis isolates were resistant to nine antibiotics (ampicillin, cefotaxime, ceftazidime, cefazolin, cephalothin, amikacin, nalidixic acid, streptomycin, and tetracycline). All cephalosporin-resistant Salmonella Enteritidis isolates exhibited the extended-spectrum β-lactamase (ESBL) phenotype and carried the gene encoding CTX-M-15, the most prevalent ESBL enzyme worldwide. Based on molecular subtyping performed using the automated rep-polymerase chain reaction (PCR) system (DiversiLab), the isolates showing ≥ 95 similarity in their rep-PCR banding patterns were classified into 5 pulsotypes. Given that cephalosporins are the drugs of choice for invasive Salmonella infections, the high incidence of ESBL-producing strains in chicken should emphasize the necessity of regular monitoring of the occurrence of antibiotic-resistant ESBL-positive Salmonella strains in poultry meat.

In this study, Karmali agar was modified by adding tazobactam (T-Karmali agar) to suppress the growth of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli , which frequently contaminates raw poultry meat. By inoculating 30 Campylobacter spp. strains and 25 ESBL-producing E. coli strains onto Karmali agar and T-Karmali agar containing various concentrations of the antibacterial agent, we determined the optimum concentration of tazobactam to be 4 mg/liter. The Campylobacter spp. isolation rate on T-Karmali agar (13.3%) was higher than that on Karmali agar (8.3%), although the difference was not significant (P0.05). However, T-Karmali agar showed a significantly greater selectivity than Karmali agar, as evaluated by comparing the numbers of contaminated agar plates (20.8 versus 82.5%; P0.05) and the growth indexes (1.36 versus 2.83) of competing flora. The predominant competing flora on Karmali and T-Karmali agar were identified as ESBL-producing E. coli . Thus, T-Karmali agar might be effective for determining the real prevalence of Campylobacter in raw poultry and, especially, contamination with ESBL-producing E. coli .

Culture-based detection of nontyphoidal Salmonella spp. in foods requires at least four working days; therefore, new detection methods that shorten the test time are needed. In this study, we developed a novel single-step Salmonella enrichment broth, SSE-1, and compared its detection capability with that of commercial single-step ONE broth-Salmonella (OBS) medium and a conventional two-step enrichment method using buffered peptone water and Rappaport-Vassiliadis soy broth (BPW-RVS). Minimally processed lettuce samples were artificially inoculated with low levels of healthy and cold-injured Salmonella Enteritidis (100 or 101 colony-forming unit/25 g), incubated in OBS, BPW-RVS, and SSE-1 broths, and streaked on xylose lysine deoxycholate (XLD) agar. Salmonella recoverability was significantly higher in BPW-RVS (79.2%) and SSE-1 (83.3%) compared to OBS (39.3%) (p

We compared standard culture methods as well as conventional PCR and real-time PCR for the detection of Listeria monocytogenes (L. monocytogenes) in milk, cheese, fresh-cut vegetables, and raw beef that have different levels of background microflora. No statistical differences were observed in sensitivity between the two selective media in all foods. In total, real-time PCR assay exhibited statistically excellent detection sensitivity (p

The objective of this study was to evaluate the effects of soy sauce on the physicochemical and textural properties of tumbled chicken breasts. Chicken breasts marinated with distilled water (Con), 4% NaCl solution, 4% NaCl and lactic acid solution (pH 4.9), and soy sauce solution (4% salt concentration and pH 4.9) were vacuum tumbled at 3°C for 60 min. The chicken breast marinated with soy sauce solution showed lower lightness and higher redness and yellowness due to the color of the soy sauce. The acidic marinades led to a decrease in pH value of tumbled chicken breast. The acidic marinades increased collagen solubility of sample compared with 4% NaCl solution, resulting in decreased shear force. Water-holding capacity, marination and cooking yields, and solubility of myofibrillar proteins were mainly affected by the presence of salt in the marinade, rather than by pH alternation. Our results suggested that soy sauce marination can improve the tenderness of tumbled chicken breast.

Organic foods have risen in popularity recently. However, the increased risk of bacterial contamination of organic foods has not been fully evaluated. In this study, 100 samples each of organic and conventional fresh vegetables (55 lettuce samples and 45 sprout samples) sold in South Korea were analyzed for aerobic bacteria, coliforms, Escherichia coli, and Bacillus cereus. Although the aerobic bacteria and coliform counts were not significantly different between the two farming types (p 0.05), the occurrence rate of B. cereus was higher in organically cultivated vegetables compared with those grown conventionally (70% vs. 30%, respectively). The mean contamination level of B. cereus-positive organic samples was also significantly higher (1.86 log colony-forming unit [CFU]/g vs. 0.69 log CFU/g, respectively) (p 0.05). In addition, six samples of organic vegetables were found to be contaminated with B. cereus at over 4 log CFU/g categorized as unsatisfactory according to Health Protection Agency guideline. The relatively higher occurrence rate of B. cereus in organic vegetables emphasizes the importance of implementing control measures in organic vegetable production and postharvest processing to reduce the risk of food poisoning.

Overgrowth of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli on modified charcoal-cefoperazone-deoxycholate agar (mCCDA) is the most common confounding factor for the isolation of Campylobacter from poultry samples. mCCDA modified by supplementation with tazobactam, an ESBL inhibitor, was evaluated for Campylobacter isolation from chicken carcass rinse with regard to isolation rate and selectivity. In total, 120 whole chicken carcasses purchased from retail stores were rinsed with buffered peptone water enriched with 2× blood-free Bolton broth at 42°C for 48 h and then inoculated onto mCCDA with and without tazobactam supplementation (mCCDA or T-mCCDA) at 42°C for 48 h under microaerobic conditions. Suspect colonies were subcultured and confirmed by colony PCR. Plates with tazobactam exhibited a higher Campylobacter isolation rate (56.7% vs. 30.8%, p 0.05) and selectivity (0.8 vs. 83.3% plates contaminated with non-Campylobacter, p 0.05) than mCCDA. Thus, tazobactam-supplemented mCCDA would be a useful option for qualitative detection of Campylobacter in chicken carcass rinse.

We evaluated the effectiveness of 2 selective enrichment broths, Rappaport-Vassiliadis Soy (RVS) and Muller-Kauffmann tetrathionate with novobiocin (MKTTn), for the isolation of Salmonella from chicken carcasses obtained from 3 different types of retail markets. We also compared a chromogenic agar, chromID Salmonella agar (SM-ID 2), with a classic plating medium, xylose lysine deoxycholate agar (XLD). Salmonella were isolated from 118 of the 180 samples (65.5%). Salmonella were detected in 105 samples (88%) plated on XLD and 111 samples (94%) plated on SM-ID 2 when RVS broth was used for enrichment, and 43 samples (36.4%) plated on XLD and 67 samples (56.8%) plated on SM-ID 2 when the MKTTn broth was used. The highest sensitivity was found in the RVS-XLD combination (0.99), followed by RVS-SM-ID 2 (0.97). The specificity of the RVS-SM-ID 2 combination was the highest (0.89), but that of the MKTTn-XLD combination was zero. The results of this study indicate that the selective enrichment broths had a great effect on the sensitivity and specificity of plating media, and our study confirms that the RVS broth is the most suitable enrichment for the investigation of Salmonella in chicken carcasses. This observation suggests that use of RVS broth for selective enrichment and SM-ID 2 for selective isolation may be the best combination to determine the presence of Salmonella in chicken carcasses.

Supplementation effect of fish oil and/or fumarate on production of conjugated linoleic acid (CLA) and methane by rumen microbes was examined when incubated with safflower oil. One hundred and twenty milligrams of safflower oil (SO), safflower oil with 24 mg fish oil (SOFO), safflower oil with 24 mmol/L fumarate (SOFA), or safflower oil with 24 mg fish oil and 24 mmol/L fumarate (SOFOFA) were added to the 90 mL culture solution. The culture solution was also made without any supplements (control). The SOFA and SOFOFA increased pH and propionate (C3) compared to other treatments from 3 h incubation time. An accumulated amount of total methane (CH(4) ) for 12 h incubation was decreased by all the supplements compared to control. The concentrations of c9,t11CLA for all the incubation times were increased in the treatments of SOFO, SOFA and SOFOFA compared to SO. The highest concentration of c9,t11CLA was observed from SOFOFA among all the treatments at all incubation times. Overall data indicate that supplementation of combined fumarate and/or fish oil when incubated with safflower oil could depress CH(4) generation and increase production of C(3) and CLA under the condition of current in vitro study.

Curcuma species are medicinal herbs with various pharmacological activities. They have a characteristic yellow color and contain curcuminoids which are natural antioxidants. In this study, Curcuma aromatica (CA) and Curcuma longa (CL) extracts were gamma-irradiated for improving the color, and the irradiation effects on the curcuminoids contents in CA and CL extracts were determined in order to evaluate if CA can replace CL on the market, where the price of CA is 70% lower than the price of CL. The Hunter color L *-values were increased significantly in all the samples with increasing dose, while the a *-values and b *-values decreased, which implies that the color of the CA and CL extracts changed from dark yellow to brighter yellow. Curcuminoids contents of all the samples were evaluated, and CA contains more curcuminoids than CL. These results indicated that irradiation improved the properties of CA for possible industrial use in manufacturing food and cosmetic industrial products.

The objective of this investigation was to determine the prevalence and characteristics of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae in ready-to-eat (RTE) vegetables. A total of 189 RTE vegetable samples (91 sprouts and 98 mixed salads) were collected in a retail market in South Korea from October 2012 to February 2013. The prevalence of ESBL-producing E. coli and K. pneumoniae was 10.1%. Of these, 94.7% were from the sprout samples. All isolates were resistant to cefotaxime, and many of the ESBL producers were also resistant to non-β-lactam antibiotics, including gentamicin, trimethoprim/sulfamethoxazole, and ciprofloxacin (73.7%, 63.2%, and 26.3% respectively). TEM-1, SHV-1, -2, -11, -12, -27, -28 and -61, and CTX-M-14, -15 and -55 β-lactamases were detected alone or in combination. The genetic platforms of all CTX-M producing isolates were ISEcp1-blaCTX-M-orf477 and ISEcp1-blaCTX-M-IS903 in CTX-M groups 1 and 9, respectively. To our knowledge, this is the first report of the prevalence and characterization of ESBL-producing E. coli and K. pneumoniae isolated from RTE vegetables. The results of this study indicate that RTE vegetables, sprouts, in particular, may play a role in spreading antimicrobial resistant bacteria and ESBL genes to humans.

We compared Bolton enrichment broth supplemented with antimicrobial triclosan (T-Bolton broth) and normal Bolton broth for the isolation of Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) from chicken carcass rinse. Whole chickens were rinsed with buffered peptone water prior to enrichment in normal Bolton broth or T-Bolton broth, followed by inoculation onto modified charcoal-cefoperazone-deoxycholate agar (mCCDA). Suspect colonies were confirmed by PCR. We observed a significantly higher number of C. jejuni or C. coli-positive samples in the T-Bolton broth (71.3%) than in the normal Bolton broth (27.5%) (p0.05). Furthermore, the number of contaminated mCCDA plates was lower after enrichment in T-Bolton broth (3.8%) than in the normal Bolton broth (75%) (p0.05), indicating that T-Bolton broth has higher selectivity. Finally, we identified extended-spectrum β-lactamase-producing Escherichia coli as the predominant competing flora in normal Bolton broth. In conclusion, the use of T-Bolton broth results in significant elimination of competing bacteria.