• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1614-1623
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• 2010

Bacteria were isolated from roots of sugarcane varieties grown in the fields of Punjab. They were identified by using API20E/NE bacterial identification kits and from sequences of 16S rRNA and amplicons of the cpn60 gene. The majority of bacteria were found to belong to the genera of Enterobacter, Pseudomonas, and Klebsiella, but members of genera Azospirillum, Rhizobium, Rahnella, Delftia, Caulobacter, Pannonibacter, Xanthomonas, and Stenotrophomonas were also found. The community, however, was dominated by members of the Pseudomonadaceae and Enterobacteriaceae, as representatives of these genera were found in samples from every variety and location examined. All isolates were tested for the presence of five enzymes and seven factors known to be associated with plant growth promotion. Ten isolates showed lipase activity and eight were positive for protease activity. Cellulase, chitinase, and pectinase were not detected in any strain. Nine strains showed nitrogen fixing ability (acetylene reduction assay) and 26 were capable of solubilizing phosphate. In the presence of 100 mg/l tryptophan, all strains except one produced indole acetic acid in the growth medium. All isolates were positive for ACC deaminase activity. Six strains produced homoserine lactones and three produced HCN and hexamate type siderophores. One isolate was capable of inhibiting the growth of 24 pathogenic fungal strains of Colletotrichum, Fusarium, Pythium, and Rhizoctonia spp. In tests of their abilities to grow under a range of temperature, pH, and NaCl concentrations, all isolates grew well on plates with 3% NaCl and most of them grew well at 4 to $41^{\circ}C$ and at pH 11.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.165-171
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• 2016

The objective of this study is to evaluate the compressive strength development and ecological characteristics of mortars using expanded vermiculite absorbing bacteria as a fundamental investigation to develop precast eco-concrete products. For bacterial growth under the high-alkalinity and high-dried environments within hardened mortars and for creating plant growth function to mortars, Bacillus alcalophilus and Rhodoblastus acidophilus were separated and cultured. The cultured bacteria were absorbed into expanded vermiculite selected for bacteria shelter. The expanded vermiculite absorbing bacteria was then added into mortar mixture as a volumetric replacement of fine aggregate. Test results showed that the developed technology is very effective in enhancing the plant growth onto the hardened mortars and reducing the COD and T-N concentration in raw water. The optimum replacement level of expanded vermiculite absorbing bacteria can be recommended to be less than 10% considering the compressive strength development and cost of mortars along with the ecological effectiveness.

• Korean Journal of Food Science and Technology
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• v.11 no.3
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• pp.200-205
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• 1979

Effects of monosodium phosphate, disodium phosphate, trisodium phosphate, ${\alpha}-polygel$, sodium ultrametaphosphate and sodium tripolyphosphate on the growth of bacteria, pH and acidity in single culture of Lactobacillus bulgaricus and mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus were investigated. Phosphates exerted definite effect in enhancing the growth of the bacteria and acidity of the fermented milk. For the single-culture of Lactobacillus bulgaricus monosodium phosphate and sodium tripolyphosphate were most effective in terms of bacterial growth and acidity, whereas for the mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus monosodium phosphate and disodium phosphate showed the best results. In the presence of the phosphates, particularly of trisodium phosphate, the decrease of viable count of bacteria in fermented milk during storage was reduced significantly. The stability of the fermented milk prepared with the mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus was improved by the addition of phosphates, particularly of monosodium phosphate.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.185-192
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• 2020

The global carbon storage regulator (Csr) system is conserved in bacteria and functions as a regulator in the exponential and stationary phases of growth in batch culture. The Csr system plays a role in the central carbon metabolism, virulence, motility, resistance to oxidative stress, and biofilm formation. Although the Csr was extensively studied in Gram negative bacteria, it has been reported only in the control of motility in Bacillus subtilis among Gram positive bacteria. The goal of this study was to explore the role of the csrA gene of Bacillus licheniformis M2-7 on motility and the bacterial ability to use hydrocarbons as carbon source. We deleted the csrA gene of B. licheniformis M2-7 using the plasmid pCsr-L, harboring the spectinomycin cassette obtained from the plasmid pHP45-omega2. Mutants were grown on culture medium supplemented with 2% glucose or 0.1% gasoline and motility was assessed by electron microscopy. We observed that CsrA negatively regulates motility by controlling the expression of the hag gene and the synthesis of flagellin. Notably, we showed the ability of B. licheniformis to use gasoline as a unique carbon source. Our results demonstrated that CsrA is an indispensable regulator for the growth of B. licheniformis M2-7 on gasoline.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.202-206
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• 2000

Feasibility of microbial culture media using by-product of salt fermented kanary was investigated. Gram negative strain, Escherichia coli, and Gram positive strain, Bacillus subtilis, and bioluminescent Photobacterium Phosphoreum were incubated with kanary by-Product media (KB media). Compared with LB media, KB media had enough carbon source, but lacked nitrogen source and growth factor. When 0.5% of peptone as a nitrogen source and 0.3% of yeast extract as nitrogen and growth factor source were fortified in KB media, the cell population rate was similar to LB media. Also, when 0.5% of yeast extract was fortified to KB media, it showed the same result as in LB media. The price of KB media with fortification of 0.5% peptone and 0.3% yeast extract, and 0.5% of yeast extract is only 46 and 19% of that of LB media, respectively. These results showed that kanary by-Product could be a good and cheaper bacterial culture media if small amount of nitrogen source and growth factor were added.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.6-11
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• 2007

This study was carried out to evaluate the growth characteristics of Propionbacterium freudenreichii KCCM 31227 and production of organic acids in whey broth. Bacterial growth and increase rate of TTA (Total Titratible Acidity) were analysed. Log numbers of Propionibacterium freudenreichii KCCM 31227 was at the highest peak at 7.5${\times}10^7$ cfu/ml in fementation of 72 hr in 12% whey broth treated with low temperature long time method (60$^{\circ}C$, 30min) containing 1% yeast extract. TTA value of 12% whey broth treated with low temperature long time method and containing 1% yeast extract showed the highest peak at 5.2 in fermentation of 72 hr. The increase rate of cells and TTA in whey broth revealed almost the same tendency. Production of propionic and acetic acids showed higher value in the whey broth treated with low temperature long time method.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.375-379
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• 2005

Physicochemical properties, intestinal microbial growth, and inhibitory effects of alcohol-insoluble polysaccharide (AIP) extracted from cucumber peel were investigated. AIP was composed of 14.54% crude protein, 1.04% crude lipid, 13.74 % crude ash, 9.1% soluble dietary fiber, and 41.2% insoluble dietary fiber. AIP showed low bulk density (0.18 g/mL) and water-holding capacity (6.39 g/g), and high oil-holding capacity (3.96 g/g). Pectic substance fractions [water-soluble pectic substance (WSP), ethylenediaminetetraacetic acid-soluble pectic substance (ESP), and alkali-soluble pectic substances (ASP)] and hemicellulose fractions [1 M KOH-soluble hemicellulose (KHP1) and 4 M KOH-soluble hemicellulose (KHP4)] were obtained from sequential chemical fractionation of AIP. WSP showed higher total sugar contents than total uronic acid contents, whereas opposite results were observed in ESP and ASP. Molecular weight distributions of three pectic substance fractions were in order of ASP>ESP>WSP. Ion exchange chromatogram pattern of WSP was different from those of ESP and ASP. Major component of WSP was fraction eluted by 0.05 M ammonium acetate buffer, whereas that of ESP and ASP was fraction eluted by 0.2 M NaOH. WSP and ASP showed growth-promoting activities against Lactobacillus brevis, Bifidobacterium bifidum, and B. longum, whereas B. bifidum and B. longum for ESP. KHP1 and KHP4 fractions had significant growth-promoting activities against B. bifidum.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.351-353
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• 2017

Chryseobacterium sp. strain T16E-39, isolated from roots of a tomato plant, promotes plant growth and suppresses phytophthora blight and bacterial wilt diseases. The complete genome of strain T16E-39 consists of a circular chromosome with 4,872,888 base pairs with a G + C content of 35.22%. The genome includes 4,289 coding sequences, 15 rRNAs, and 71 tRNAs. We detected genes involved in phosphate solubilization, phytohormone regulation, antioxidant activity, chitin degradation, and the type IX secretion system (T9SS) that may be related to growth promotion and disease suppression in plants.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.421-429
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• 2019

The purpose of this study was to investigate the effects of intestinal bacteria on the growth of enteric bacteria, especially infectious harmful bacteria such as food poisoning, gastritis and enteritis, and the growth of beneficial bacteria. By dividing the rat into three test groups; normal control group, Loperamide-treated group, and supercritical heat-treated radish complex extracts(HRE)-treated group, animal experiments were performed to inhibit the growth of harmful bacteria without affecting the growth of beneficial bacteria in the intestine. It was found that it can be usefully used as an effective and safe health food composition for improving intestinal function and bacterial intestinal disease. In particular, it can be concluded that supercritical heat-treated radish complex extract is a safe food that does not show any side effects even when taken for a long time.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1045-1059
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• 2021

Various abiotic stressors like drought, salinity, temperature, and heavy metals are major environmental stresses that affect agricultural productivity and crop yields all over the world. Continuous changes in climatic conditions put selective pressure on the microbial ecosystem to produce exopolysaccharides. Apart from soil aggregation, exopolysaccharide (EPS) production also helps in increasing water permeability, nutrient uptake by roots, soil stability, soil fertility, plant biomass, chlorophyll content, root and shoot length, and surface area of leaves while also helping maintain metabolic and physiological activities during drought stress. EPS-producing microbes can impart salt tolerance to plants by binding to sodium ions in the soil and preventing these ions from reaching the stem, thereby decreasing sodium absorption from the soil and increasing nutrient uptake by the roots. Biofilm formation in high-salinity soils increases cell viability, enhances soil fertility, and promotes plant growth and development. The third environmental stressor is presence of heavy metals in the soil due to improper industrial waste disposal practices that are toxic for plants. EPS production by soil bacteria can result in the biomineralization of metal ions, thereby imparting metal stress tolerance to plants. Finally, high temperatures can also affect agricultural productivity by decreasing plant metabolism, seedling growth, and seed germination. The present review discusses the role of exopolysaccharide-producing plant growth-promoting bacteria in modulating plant growth and development in plants and alleviating extreme abiotic stress condition. The review suggests exploring the potential of EPS-producing bacteria for multiple abiotic stress management strategies.