• Korean Journal of Microbiology
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• v.54 no.2
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• pp.167-168
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• 2018

Here we report the complete genome sequence of Staphylococcus xylosus S170, strong biofilm-producing strain, which comprised a single circular 2,910,005 bp chromosome and 32.97% G + C content. The genome included 2,674 protein-coding sequences, 22 rRNA genes, and 57 tRNA genes. Gene analysis of S. xylosus S170 could contribute to better understanding of biofilm-forming mechanisms.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.376-380
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• 2000

This study was conducted to investigate protein and carbohydrate utilization of Micrococcus varians, Staphylococcus carnosus and Staphylococcus xylosus. Sensitivity to pH, sodium chloride, potassium sorbate and sodium nitrite of these strains was also determined. In Chinese-style beaker sausage manufacturing, the growth rate of these strains during the curing period ($20^{\circ}C$ and $30^{\circ}C$) was evaluated. The results indicated that no strains could hydrolyze azo-casein and sarcoplasmic protein and only S. xylosus could hydrolyze gelatin at $30^{\circ}C$. All of these strains could oxidize and ferment fructose and mannitol. S. carnosus and S. xylosus could slightly oxidize lactose and utilize citrate. Arabinose was oxidized by S. xylosus and sorbitol was oxidized by S. carnosus. Growth of M. varians was restricted at pH 5.0 and S. carnosus and S. xylosus were restricted at pH 4.5. S. xylosus and S. carnosus were able to grow with 0.1~0.5% potassium sorbate, 50~200 ppm sodium nitrite or 1~15% sodium chloride. S. xylosus had a higher growth rate than the other strains. Staphylococcus species grew well during curing period of Chinese-style beaker sausage then followed by Micrococcaceae.

• Journal of Life Science
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• v.11 no.5
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• pp.457-463
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• 2001

A bacterial strain SC-22 which produced alkaline lipase was isolated from salf-fermented shrimps. Strains SC-22 was identified as Staphylococcus xylosus. An alkaline lipase excreted by Staphylococcus xylosus SC-22 was purified by ammonium sulfate predipitation and column chromatography on Sephadex G-100 and DEAE-Sephace. The specific activity of purified lipase was 756U/mg of protein with 17.2% yield. The approximate molecular weight of the purified enzyme was 47 kDa. The partially purified lipase preparation had and optimum temperature of 4$0^{\circ}C$, an optimum pH of 8.0, and a stable of 5~10. Lipase activities were enhanced by salt ions such as $Ca^{2+}$, $Mg^{2+}$,N $a^{2+}$ while inhibited remarkably by heavy metal ions, C $u^{2+}$ and P $b^{2+}$.EX> 2+/.

• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.458-463
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• 2022

We evaluated the antibiotic susceptibilities, hemolytic activities, and technological properties of 36 Staphylococcus xylosus strains and 49 S. pseudoxylosus strains predominantly isolated from fermented soybean foods from Korea. Most of the strains were sensitive to chloramphenicol, erythromycin, gentamycin, kanamycin, lincomycin, oxacillin, tetracycline, and trimethoprim. However, 23 strains exhibited potential phenotypic acquired resistance to erythromycin, lincomycin, and tetracycline. Based on breakpoint values for staphylococci from the Clinical and Laboratory Standards Institute, >30% of the isolates were resistant to ampicillin and penicillin G, but the population distributions in minimum inhibitory concentration tests were clearly different from those expected for acquired resistance. None of the strains exhibited clear α- or β-hemolytic activity. S. xylosus and S. pseudoxylosus exhibited salt tolerance on agar medium containing 20% and 22% (w/v) NaCl, respectively. S. xylosus and S. pseudoxylosus strains possessed protease and lipase activities, which were affected by the NaCl concentration. Protease activity of S. pseudoxylosus was strain-specific, but lipase activity might be a characteristic of both species. This study confirms the potential of both species for use in high-salt soybean fermentation, but the safety and technological properties of strains must be determined to select suitable starter candidates.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.570-574
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• 2003

This study investigate the effects of starter cultures on the color stability of Chinese-style sausage. The samples were inoculated with $10^7cfu\;g^{-1}$ meat of either Staphylococcus carnosus or Staphylococcus xylosus. After mixing, curing at either $4^{\circ}C$ or $20^{\circ}C$ for 20 h and then drying at $50^{\circ}C$ for 5 h, the samples were then either vacuum packed or hung at $4^{\circ}C$ and $25^{\circ}C$ (85% R. H.). The pH, nitrite content, nitrosyl pigment content, metmyoglobin and L-, a-, b- values were measured. The pH value still remained above 6.0 during storage. Nitrite residue of all samples decreased after storage at $25^{\circ}C$ for 7 days. The samples inoculated with S. carnosus and S. xylosus had higher nitrite content (20.9-34.7 ppm) than the control (p<0.05). Samples inoculated with S. carnosus and S. xylosus had higher nitrosyl pigment content and lower metmyoglobin content than those of the control. The L- and b- values of all samples decreased but the a- values increased with storage time. The result suggested that S. carnosus and S. xylosus starter cultures be used to improve color stability of Chinese-style sausage.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.308-308
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• 2018

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1173-1177
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• 2000

This study investigated the nitrate reduction ability of Micrococcaceae on pigment formation in Chinese- style sausage. One hundred ppm sodium nitrite and 150 ppm sodium nitrate was added asepticly to ground pork which was then inoculated with $10^7CFU/g$ of either Micrococcus varians, Staphylococcus carnosus or Staphylococcus xylosus. All samples were cured at $20{^{\circ}C}$ or $30{^{\circ}C}$ for 3 days and then color, residue nitrite, nitrosyl pigment and residue nitrate were determined. The results indicated that samples inoculated with S. xylosus had higher a- and b- values due to nitrate reduction and pigment production after 3 days curing and these values were higher at the higher curing temperature. The nitrosyl pigment of the samples with S. xylosus had highest values after 3 days curing at both $20{^{\circ}C}$ and $30{^{\circ}C}$. However, sample inoculated with S. carnosus and S. xylosus had lower nitrate contents than the sample inoculated with M. varians. At $30{^{\circ}C}$ as well as S. carnosus and M. varians had a stronger decreasing in nitrate concentration during curing at $20{^{\circ}C}$. Moreover, samples inoculated with S. xylosus and S. carnosus had a higher residual nitrite content during curing at $20{^{\circ}C}$ or $30{^{\circ}C}$. In conclusion, two Staphylococci strains tested were most optimum starter cultures for improving pigment formation during Chinese-style sausage curing.

• Food Science of Animal Resources
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• v.39 no.6
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• pp.877-887
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• 2019

This study was performed to determine changes in mutagenicity and biogenic amine concentrations in sausages fermented with six different starter cultures treated with vitamins C and E. Six different types of fermented sausages with different combination of starter cultures were manufactured. T1, Pediococcus acidilactici; T2, P. pentosaceus and Staphylococcus carnosus; T3, S. carnosus, S. xylosus, Debaryomyces hansenii, Lactobacillus curvatus, and P. pentosaceus; T4, S. carnosus and L. sakei; T5, S. xylosus and L. plantarum; and T6, Penicillium nalgiovensis. After treatment with vitamins C and E in fermented sausages, changes in mutagenicity and biogenic amine concentrations were measured. The sausages fermented with Staphylococcus xylosus and Lactobacillus plantarum starter cultures showed the most effective antimutagenic activity (p<0.05). The mutagenicity was further decreased in the sausages treated with vitamins C and E (p<0.05), regardless of the starter cultures. The use of Pediococcus acidilactici, S. xylosus, L. plantarum, and Penicillium nalgiovensis as starter cultures was effective in decreasing biogenic amine concentrations (p<0.05). In addition, vitamin E was more effective in decreasing the biogenic amine concentrations than vitamin C. In conclusion, we recommend the use of S. xylosus and L. plantarum as starter cultures, in addition to the use of vitamins C and E, to reduce the potential risk of meat mutagens in fermented sausages.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.359-363
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• 2019

Meju is a spontaneously fermented soybean product produced in Korea. We isolated the bacteria of the genera Bacillus, Enterococcus, and Staphylococcus from 12 meju samples collected from five regions of Korea using selective media, and we identified them based on the sequence analysis of 16S ribosomal RNA and gmk (guanylate kinase) genes. Bacillus and Enterococcus strains were identified from all samples and the numbers of Bacillus strains in the 11 samples were >15% of the total cell number. Therefore, the genus Bacillus was confirmed as the predominant bacterial group of meju. Staphylococcus strains were identified from six samples. The identified 151 Bacillus isolates predominated in the following order: B. velezensis, B. sonorensis, B. subtilis, and B. licheniformis. Among the 165 Enterococcus isolates, 163 strains were identified as E. faecium. Eighty-two Staphylococcus isolates were classified into six species of coagulase-negative Staphylococcus group and S. xylosus was the predominant species.

• Journal of Microbiology and Biotechnology
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• v.6 no.5
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• pp.340-346
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• 1996

In order to find out if staphylococci occur in significant numbers in Korean fermented fish products, a total of 40 different fermented fish products were collected from different markets in Korea and analyzed for their physico-chemical and microbiological states. The pH, salt concentration and water activity of the products were measured and the total viable cell count and the number of Staphylococcus grown on mannitol salt agar were determined. The identification of the strains of Staphylococcus were made by API Staph Strip and MIS identification kits, and the physiological properties of the identified strains were further characterized by different conventional methods. The pH, salt content and water activity of fermented fish samples varied widely from 4.8 to 7.1, 7.4-28.7$%$ and 0.77-0.84, repectively, depending on the type of product. The total viable cell count varied from $10^4-10^9$ cfu/ml, and most of the samples had $10^5-10^6$ cfu/ml No correlation was found between the viable cell count and the pH, NaCl concentration and water activity of the samples. Among the 35 colonies identified as Staphylococcus strains by the identification kits, S. xylosus was the most frequently occurring strain marking 17, and S. warneri was 8, S. epidermidis 4 and S. cohnii 2. S. hominis, S. saprophyticus, S. haemolyticus and S. aureus were also identified once each. In some samples (K-3, P-6, K-8, G-5 and G-10), 2-3 different species of Staphylococcus were found. Considering the region of sampling, among the 10 samples from Kunsan 5 were identified as S. warneri, while in the other regions S. xylosus was predominant. Although the physiological characteristics of the identified strains were generally consistent with those in Bergey's Manual, some discrepances were also observed. All the strains were highly salt tolerant, growing in the media containing over 18$%$ NaCl. All the strains except S. aureus (G-11) showed negative in hemolysis activity, plasma coagulation and DNase tests. All the strains including S. aureus (G-11) showed negative in enterotoxin test.