• The Korean Journal of Soil Zoology
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• v.3 no.2
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• pp.51-57
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• 1998

A new rod-shaped endospore-forming bacterium isolated from the hindgut flora of the termite, Reticulitermes speratus kyushuenesis Morimoto is described. The isolate stained Gram positive, but the KOH test and the test for L-alanine aminopeptidase were negative. The length of a single cell varies from 2.5-9.0 $\mu $m, and the cell is about 0.5-0.7$\mu $m thick. The isolate had a high cellulolytic ability and was identified as Bacillus amyloliquefaciens.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.206-213
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• 2010

In this study, the antibacterial activities of essential oil from Zanthoxylum schinifolium against four Gram-positive bacteria and six Gram-negative bacteria were investigated. The antibacterial activity of the oils was determined using the agar-well diffusion assay, MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration). In particular, essential oil from Z. schinifolium showed higher antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. Essential oil from Z. schinifolium displayed large inhibition zones especially against Bacillus cereus (31 mm). At concentrations between 0 and $20\;{\mu}g/mL$ the oils showed an antibacterial effect against both Gram-negative and Gram-positive bacteria. The minimum inhibitory concentration (MIC) values against nine bacteria ranged from 1.25 to $5\;{\mu}g/mL$. The minimum bactericidal concentration (MBC) values against eight bacterial ranged from 2.5 to $20\;{\mu}g/mL$, except Shigella sonnei. Furthermore, our finding on the antibacterial activities of essential oils from Zanthoxylum schinifolium validated the use of this plant for medical purposes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.1013-1020
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• 1997

The cellular fatty acids of 47 marine bacteria representing the genus Alteromonas, Arthrobacter, Bacillus, Micrococcus, Pseudomonas, Shewanella, Staphylococcus and Stenotrophomonas were determined by a gasliquid chromatographic analysis. Sixty-eight different fatty acids with 10 to 20 carbon atoms were detected in marine bacteria. Of the eight genus examined, 14:0, 16:0 and i17:0 were detected in all, while i14:0, a15:0, i16:0, and 15:0 were found in most of all. There were significant differences in the fatty acid patterns between Gram positive and Gram negative bacteria. Bacteria of Gram positive genus showed relatively high contents of the branched type fatty acids, while the major fatty acids in Gram negative were unsaturated and straight forms. Phylogenetic relationships between marine bacteria defined by the cellular fatty acid patterns represented obvious differences between Gram positive and Gram negative genera, even in respective genus. Therefore, the bacterial classification and identification can be accomplished more easily and rapidly based on the cellular fatty acid profiles than the conventional methods.

• YAKHAK HOEJI
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• v.10 no.4
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• pp.7-20
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• 1966

1. Of the 32 extracts from Genus of lishenes broth tested for antimicrobial activity, 28 inhibited at least one of the 3 test microorganisms used. 2. Twenty seven lichnes broth from 32 species tested were active against at least one of the Gram-positive bacteria M. pyogenes var, aureus 203 p, and twenty four lichenes broth from 32 Species tested were active against at least one of the Gram-positive bacteria Bacillus subtilis ATCC 6633. 3 Twenty five lichenes broth from 32 species tested were active against at least one of the Gram-negative bacteria Escherichia coli 0.126. 4. The antibiotic substances in lichenes were readily extracted by organic solvents.

• Korean Journal of Pharmacognosy
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• v.23 no.4
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• pp.240-247
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• 1992

Impatiens balsamina Linne(Balsaminaceae) known as 'BONG SUN HWA' in Korea and has been used for the treatment of scrofulosis, carbunculus and dysenteria etc. Bioassay-guided fractionation of MeOH extract from the whole plants of Impatiens balsamina has afforded a simple naphthoquinone derivative, 2-methoxy-1,4-naphthoquinone. The structure of this compound was established by spectroscopic methods. This compound possessed strong antifungal activity against Candida albicans, AspergiIlus niger, Crytococcus neoformans and Epidermophyton floccusum. The activity of 2-methoxy-1,4-naphthoquinone on E. floccusum $(MIC{\;}:{\;}5.0{\;}{\mu}g/ml)$ was the same potency as that of nystatin. It showed also strong antibacterial activity against gram-positive bacteria Bacillus subtilis as well as gram-negative bacteria Salmonella typhimurium. Although the activity of this compound on gram-negative bacteria was lower than that of gram-positive bacteria.

• Advances in Traditional Medicine
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• v.9 no.2
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• pp.174-181
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• 2009

Pterocarpus marsupium, Clitoria ternatea, and Sanseveiria cylindrica are some of the important and endangered medicinal plant species of India. Despite of medicinal properties, antibacterial potential of the plants have not yet been explored. The present study was designed to optimize the in vitro technique for micropropagation and to screen the extracts from leaves and in vitro raised calli for antibacterial properties. Excised leaf-explants from the parent plants were surface sterilized and cultivated on Murashige & Skoog's (MS) medium containing $N^6$-benzyladenine (BA) in concentrations of 1, 2, 5, and $10{\mu}M$. Optimal growth of calli was noticed at a concentration of $5{\mu}M$, therefore the extracts from calli grown at this concentration were further studied for antibacterial activity. Both alcoholic and aqueous extracts from leaves of respective plants, and their in vitro raised calli were tested for antibacterial activity by agar well diffusion method against a range of Gram-positive and Gram-negative bacteria. Aqueous extracts showed antibacterial activity against limited number of bacterial species; notably the extracts of C. ternatea which showed antibacterial activity against Streptococcus pyogenes, Bacillus subtilis and Bacillus cereus. Alcoholic extracts of all three plants showed antibacterial activity against a wider range of bacteria. Among the Gram-positive bacteria, extracts from C. ternatea showed strong antibacterial activity against Bacillus spp., whereas the extracts of S. cylindrica showed good antibacterial potential for Staphylococcus aureus, S. epidermidis and S. pyogenes. The extracts from all three plants showed antibacterial activity against Gram-negative bacteria, including, Salmonella spp. and Shigella dysenteriae; organisms causing enteric fever and dysentery. In most of the cases, the extracts from respective calli showed comparable, and in some cases better, result in comparison to the extracts from parent leaves. To the best of our knowledge this is the first preliminary report on antibacterial potential, especially through calli extracts, of these plants; and in vitro cultivation of the explants may be used to obtain phytotherapeutic compounds.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.195-200
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• 2000

Bacillus cereus BS229 was identified as a bacteriocin producer with a bactericidal activity against Bacillus thuringiensis subsp. Thomsoni BR-40. Bacillus cereus BS229 and cerein BS229, named tentatively as the bacteriocin produced by Bacillus cereus BS229, showed a narrow spectrum of actibity against Gram-positive and Gram-negative bacteria, along with yeast and molds. Production of cerein BS229 in a 5-1 fermenter followed typical kinetics of primary metabolite synthesis. The antibacterial activity of cerein BS229 on sensitive indicator cells disappeared completely by ${\alpha}-chmotrypsin$ or proteinase K, which indicates its proteinaceous nature. Cerein BS229 seemed to be very stable throughout the pH range of 2.0 of 9.0 and it was relatively heat labile, despite the fact that bacteriocin activity was still detected after being boied for 30min. Cerein BS229 actibity has been changed with some of the organic solvents such as toluene, ethanol, and chloroform. Direct detection of cerein BS229 actibity on SDS-PAGE suggested that it had an apparent molecular mass of about 8.2 kDa.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.191-196
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• 1996

The bacteriolytic enzyme produced from Bacillus subtilis SH-1 was purified and characterized, and its molecular weight was determined. The bacteriolytic enzyme activity was increased about 66.5 times via purification with recovery yield of 18.5%. The optimum pH and temperature of this enzyme were 9.0 and 50$\circ$C. The enzyme was stable within a pH range of 6.0-10.0 and unstable above 60 . The molecular weight of the enzyme was estimated to be 23,000 dalton in a form of monomer with no other subunits. Effect of the enzyme on the lysis of bacteria engaged in food posion was tested. The lysis degree was below 31% against Gram negative bacteria and above 48% in Gram positive bacteria. The values higher than 73% were obtained against Vibrio sp. and Listeria sp. As the turbidity of dissolved peptidoglycan clecreases, the free amino group levels were increased. And, based on hydrolysis of casein, this enzyme was thought to be an endopeptidase.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1518-1521
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• 2008

Bacteria sense their population density and coordinate the expression of target genes, including virulence factors in Gram-negative bacteria, by the N-acylhomoserine lactones (AHLs)-dependent quorum sensing (QS) mechanism. In contrast, several soil bacteria are able to interfere with QS by enzymatic degradation of AHLs, referred to as quorum quenching. A potent AHL-degrading enzyme, AiiA, from Bacillus thuringiensis has been reported to effectively attenuate the virulence of bacteria by quorum quenching. However, little is known about the role of AiiA in B. thuringiensis itself. In the present study, an aiiA-defective mutant was generated to investigate the role of AHA in rhizosphere competence in the root system of pepper. The aiiA mutant showed no detectable AHL￢-egrading activity and was less effective for suppression of soft-rot symptom caused by Erwinia carotovora on the potato slice. On the pepper root, the survival rate of the aiiA mutant significantly decreased over time compared with that of wild type. Interestingly, viable cell count analysis revealed that the bacterial number and composition of E. carotovora were not different between treatments of wild type and the aiiA mutant. These results provide evidence that AHA can play an important role in rhizosphere competentce of B. thuringiensis and bacterial quorum quenching to Gram-negative bacteria without changing bacterial number or composition.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.188-193
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• 2001

To evaluate antimicrobial activities of chongkukjang slime fermented by different strains, growth characteristics were compared using various standard microorganisms with addition of chongkykjang slime. Chonghkjang slime was prepared by fermenting cooked soybean after inoculating with Bacillus circulans K-1, Baciilus spp N-1 and Bacillus subtilis CH-1, respectively. Significant antimicrobial activity was observed by chongkukjang slime on gram positive bacteria (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Micrococcus luteus), gram negative bacteria(Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas fluorescens), and yeast (Pichia membranaefaciens, Saccharomyces cerevisiae, Candida albicans). In case of B. cereus growth inhibition of 80% was achieved by the addition of chongkukjang slime; on the contrary, to Escherichia coli O157:H7 only 20% inhibition was observed. Slime from Bacillus subtilis CH-1, in particular, inhibition of 40% toward bacteria and yeast, whereas slime from Bacillus circulans K-1, Bacillus spp N-1 showed only 20% inhibition.