• Korean Journal of Microbiology
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• v.52 no.3
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• pp.319-326
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• 2016

An antimicrobial bacterium to pathogenic microorganisms, strain $W5-1^T$ was isolated from Korean fermented-food Kimchi. The isolate was Gram-staining-variable, strictly aerobic, rod-shaped, endospore-forming, and motile with peritrichous flagella. It grew at $15-40^{\circ}C$, at pH 6.0-10.0, and in the presence of 0-4% NaCl. Strain $W5-1^T$ could hydrolyze esculin and xylan, and assimilate $\small{D}$-mannose, but not $\small{D}$-mannitol. Strain $W5-1^T$ showed antimicrobial activity against Listeria monocytogens, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi. The G+C content of the DNA of strains $W5-1^T$ was 52.6 mol%. The predominant respiratory quinone was menaquinone-7 (MK-7) and the major cellular fatty acids were $C_{16:0}$, antieiso-$C_{15:0}$, $C_{18:0}$, and $C_{12:0}$. The strain contained meso-diaminopimelic acid in cell-wall peptidoglycan. On the basis of 16S rRNA gene sequence and phylogenetic analysis, the strain W5-1 was shown to belong to the family Paenibacillaceae and was most closely related to Paenibacillus pinihumi $S23^T$ (98.4% similarity) and Paenibacillus tarimensis $SA-7-6^T$ (96.4%). The DNA-DNA relatedness between the isolate and Paenibacillus pinihumi $S23^T$ was 8.5%, indicating that strain $W5-1^T$ represented a species in the genus Paenibacillus. On the basis of the evidence from this polyphasic study, it is proposed that strain $W5-1^T$ is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus kimchicus sp. nov. is proposed. The type strain is $W5-1^T$ (=KACC $15046^T$ = $LMG 25970^T$).

• Journal of Food Hygiene and Safety
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• v.18 no.3
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• pp.118-124
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• 2003

For the rapid detection of various pathogenic microorganisms from food sample, various kinds of kits have been developed and commercially available in the markets. With the advantages of speed, accuracy and easiness, the market of these kits has gradually increased for the QC and QA field of food company as well as testing facilities or laboratories. In this study, the characteristics such as the detection limit and the sensitivity of immunochromatographic type of rapid detection kit (Donga Co, Korea, D-kit) for E. coli 0157:H7 developed by monoclonal antibody were examined and also the possibility of application of the kit to food samples was evaluated. The reference kits used for comparison study were Reveal E. coli 0157:H7 (Neogen Co., USA, R-kit) and VIP EHEC kit (Biocontrol Inc., USA, V-kit) occupying major market share. In the detection limit test with the E. coli 0157:H7 reference, both R-kit and D-kit showed a distinct positive reaction in $10^4$/ml and weak positive reaction in $10^3$/ml, whereas V-kit showed a same reaction in 105/ml. Also, it was identified that the culture treated with heat showed more sensitivity than no heat treated culture. The sensitivity test was conducted against 22 isolates of E. coli 0157:H7, 7 strains of non-O157:H7 verotoxin-producing E. coli, 40 strains of E. coli with different O and H antigen type, and 38 strains of non-E. coli Enterobacteriaceae, and all of the test strains except three were showed exactly three were showed exactly the same reaction against three kinds of the tested kits. All the three kinds of kits showed a positive reaction against E. coli O157:H19, E. coli O148:H18 and Salmonella galinarium. We suppose that there might be a similarity in serological property between these three strains and O157:H7. From the test results, it can be concluded that there is (was) no difference between the D-kit developed in this study and R-kit or V-kit based on the detection limit and sensitivity.

• Journal of Food Hygiene and Safety
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• v.33 no.5
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• pp.347-353
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• 2018

Red pepper is widely used as a spicy flavor ingredient in the food industry and many households. The objective of this study was to assess the total aerobic bacteria count, coliforms count and incidence of Escherichiacoli, Salmonella spp., Escherichiacoli O157:H7, Listeria monocytogenes, and Bacillus cereus in red pepper and red pepper cultivated soil. The total aerobic bacteria number in red pepper and soil were in the range of 2.97 to 8.13 and 5.91 to 7.65 log CFU/g, respectively. The coliforms in red pepper and soil were in the range of 1.87 to 6.71 and 0.67 to 6.16 log CFU/g, respectively. E. coli was detected in 3 of 54 soil samples. In 3 out 63 red pepper and 53 of 54 soil samples, B. cereus was detected, while Salmonella spp., E.coli O157:H7, and L.monocytogenes were not detected. The results from this study provide an important basic information associated with the microbiological safety of fresh vegetables. Continuous caution is needed to prevent the contamination of pathogenic microorganisms during its farming.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.61-71
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• 1988

This study was conducted to find out the effect of herbicides on soil micro-organism and soil enzyme in loam soil, and on pathogenic microorganism in continuous pepper cropping soil. The result was summarized as follows: When herbicides were treated, the number of soil microorganism generally decreased at the early stage of incubation, and gradually increased at 30 days incubation. The number of fungi was significantly decreased seven times comparison with control plot. The number of actinomycetes was increased at 20 days incubation and that of pytium was increased for all days incubation in Linuron treatment plot. Although the activity of soil enzyme tended to decrease when herbicides were treated, the activities of urease and phosphatase were higher than that of control plot at the early stage of incubation in MO, Linuron and Simetryne treatment plot. In Simetryne treatment plot, the activity of protease was increased at the early stage, and suddenly decreased after 30 days incubation. There was no significant effect of herbicides on the activities of ${\beta}$-glucosidase and polygalacturonase. The activity of cellulase was inhibited at the early stage of incubation, but that of cellulase was higher than that of control plot after 20 days incubation. High significance was showed the correlation coefficient between soil microorganisms except fungi and soil respiration as herbicides were treated, and the total microorganism and soil respiration in Linuron plot. when Dicamba and Simetryne were treated, the correlation coefficient between the total microorganism and the activities of protease and urease were considerably significant.

• Journal of Life Science
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• v.30 no.12
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• pp.1109-1117
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• 2020

In order to verify whether Zophobas atratus is an edible insect, the nutrients and harmful substances of Z. atratus larvae reared with an artificial diet (AD) and wheat bran (WB) were compared and analyzed. Based on dry weight, the crude protein content of Z. atratus larvae reared with an AD was 62.4%, 1.4 times higher than that of those reared with WB (45.2%). The crude fat content was 20.5% in the AD group, 2.3 times less than in the WB group (46.3%). The leucine content was 1.4 times higher in the AD group (4.2%) than in the WB group (3.0%). The glutamic acid content of nonessential amino acids was 1.3 times higher in the AD group (7.0%) than in the WB group (5.3%). The oleic acid content was 1.4 times higher in the WB group (37.0%) than in the AD group (26.7%). The potassium content was 1.1 times higher in the AD group (975.9 mg/100 g) than in the WB group (872.9 mg/100 g). According to the results of the toxic substances analysis, the lead and cadmium levels of the WB and AD groups were standard for edible insects. Pathogenic microorganisms, such as E. coli and salmonella, were not detected in either group. According to the results of the present analysis of nutrition and harmful substances, Z. atratus larvae raised on an AD are safe and contain various nutrients. Therefore, such larvae could be useful sources of food and feed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.139-147
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• 2021

Livestock manure is used as an organic fertilizer to replace chemical fertilizers after sufficient fermentation in an aerobic bioreactor. On the other hand, liquid manure disposal problems occur repeatedly because soil spraying is restricted during the summer when the crops are growing. To use liquid fertilizer (LF) as an additional nutrient source for crops, it is necessary to reduce the amount of suspended solids (SS) in the liquid fertilizer and secure stability problems against pathogenic microorganisms. This study examined the effects of the simultaneous SS removal and E.coli sterilization in the LF using the microbubble (MB) generator (FeMgO catalyst insertion). The remaining SS were further removed using the integrated microbubble and microfilter system. During the floating process in the MB device, the SS were removed by 57.9%, and the coliform group was not detected (16,200→0 MPN/100 mL). By optimizing the HRT of the integrated system, the removal efficiency of the SS was improved by 92.9% under the 0.1h of HRT condition. After checking the properties of the treated LF, 64.5%, 70.1%, 54.9%, and 51.5% of the TCOD, SCOD, PO4-P, and TN, respectively, were removed. The treated effluent from such an integrated system has a lower SS content than that of the existing LF and does not contain coliforms; therefore, it can be used directly as an additional fertilizer.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.123-130
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• 2023

Salmonella spp. are prevalent foodborne pathogens that are infective at relatively low concentrations, thus posing a serious health threat, especially to young children and the elderly. In several countries, the management and regulation of Salmonella spp. in food, including seafood, adhere to a negative detection standard. The risk of infection is particularly high when seafood is consumed raw, which underscores the importance of timely detection of pathogenic microorganisms, such as Salmonella. Accordingly, this study aimed to develop a combined pre-treatment and detection method that includes pre-culture and DNA extraction in order to detect five species of Salmonella at concentrations below 10 CFU/mL in seafood. The effectiveness of the proposed method was assessed in terms of the composition of the enrichment (pre-culture) medium, minimum incubation time, and minimum cell concentration for pathogen detection. Furthermore, a practical DNA extraction method capable of effectively handling high salt conditions was tested and found to be successful. Through polymerase chain reaction, Salmonella spp. Were detected and positively identified in shellfish samples at cell concentrations below 10 CFU/g. Thus, the proposed method, combining sample pre-treatment and cell culture with DNA extraction, was shown to be an effective strategy for detecting low cellular concentrations of harmful bacteria. The proposed methodology is suitable as an economical and practical in situ pre-treatment for effective detection of Salmonella spp. in seafood.