• Applied Biological Chemistry
• /
• v.37 no.4
• /
• pp.221-225
• /
• 1994

For producing single cell protein from the agricultural waste, heat treatment and antibiotics on the growth of Cellulomonas sp. KL-6, isolated in rotting leaf and the adjacent soil mixture, were examined. The organism was able to grow until 5 min. at $65^{\circ}C$, 1 min. at $75^{\circ}C$ and 1/4 min. at $85^{\circ}C$ in gradually rising temperatures. It can be Seen that preheating the suspension at $48^{\circ}C$ results in a marked decrease in heat resistance. On heating at temperature of $55^{\circ}C$ for 30 min., strain KL-6 was more resisted in the 0.1 M phosphate buffer when such substrates as casamino acid (1%), yeast extract (1%) or xylose (5%) were added to it whereas this organism was appeared weaker resistances in 0.1 M phosphate buffer when cysteine (0.03 M), sodium citrate (1%) or casein (1%) were in fused into it. Test strain was susceptible to penicillin-G $(1.563\;{\mu}g/ml)$ and ampicillin $(3.125\;{\mu}g/ml)$, but the organism was resisted to kanamycin $(>200\;{\mu}g/ml)$. The treatment of strain KL-6 with sodium dodecyl sulfate (SDS) resulted in the elimination of R-plasmid from the host strain and the elimination rate with SDS $(10{\sim}30\;{\mu}g/ml)$ was about $9.2{\sim}31.2%$, respectively.

• Journal of Life Science
• /
• v.18 no.6
• /
• pp.839-844
• /
• 2008

A strain SH-517 which produce extracellular keratinase, was isolated from the soil of a poultry waste and a poultry factory. An isolate SH-517 was identified as Bacillus sp. based on its morphological and biochemical characteristics. The optimal culture conditions for the production of keratinase by Bacillus sp. SH-517 were investigated. The optimal medium composition for keratinase production was determined to be 2.0% chicken feather as carbon source, 0.5% beef extract as organic nitrogen source, 0.5% $KNO_3$ as inorganic nitrogen source and 0.06% KCl, 0.05% NaCl, 0.04% $KH_2PO_4$, 0.03% $K_2HPO_4$ as mineral source and 0.01% yeast extract as growth factor. The optimal temperature and pH of medium were shown $40^{\circ}C$ and 8.5 with shaking culture (180 rpm/min), respectively. The maximum keratinase production reached maximum of 125 units/ml/min after 42 hr of cultivation under the optimal culturing conditions.

• Microbiology and Biotechnology Letters
• /
• v.6 no.1
• /
• pp.17-22
• /
• 1978

The microbial and chemical changes, and characterization of the predominant acid-producing bacteria in the fermenting pig feces blended with corn meal at a ratio of 50：50 were studied. The fermentation was dominated by lactobacilli, which multiplied rapidly for the first 24 hours. The acid produced during the fermentation caused rapid pH drop to pH 4.5 and halted the growth of E. coli and yeast. The initial acid producing bacteria in the mixture was predominantly Streptococcus species, which were reduced in number rapidly. After 7 days of fermentation, three lactobacilli species were appeared L. acidophilus, L. fermenti, L. delbrueckii. Chemical changes during the fermentation were also studied. The lactic acid fermentation imparted a good tangy acid flavor to the corn-feces mixture by removing or covering the .fecal ordour and made the corn-feces mixture palatable for the animal as well as halted the unwanted microbial flora. We hope the lactic acid fermentation will replace the heat processing in the utilization of animal feces.

• Microbiology and Biotechnology Letters
• /
• v.45 no.4
• /
• pp.330-342
• /
• 2017

Statistical design of experiments was employed to optimize the media composition for the production of laccase from Bacillus sp. PK4. In order to find the key ingredients for the best yield of enzyme production from the selected eleven variables viz yeast extract, glucose, zinc sulphate, copper sulphate, potassium chloride, magnesium sulphate, calcium chloride, ferrous sulphate, sodium chloride, potassium dihydrogen phosphate ($KH_2PO_4$) and dipotassium hydrogen phosphate ($K_2HPO_4$), Plackett-Burman design was applied. The $MgSO_4$, $FeSO_4$, and $CuSO_4$ showed positive estimate, and their concentration optimized further. The steepest ascent method and Box-Behnken method revealed that 1.5 mM $MgSO_4$, 0.33 g/l $FeSO_4$ and 1.41 mM $CuSO_4$ were optimal for the laccase production by Bacillus sp. PK4. This optimization strategy leads to enhancement of laccase production from 2.13 U/ml to 40.79 U/ml. Agro-wastes residues replace the carbon source glucose in the optimized media namely sugarcane bagasse, wheat bran, rice husk, and groundnut shell, among these groundnut shells (117 U/ml) was found to enhance the laccase production significantly. The laccase produced by Bacillus sp. PK4 was found to have the potential to degrade persistent organic pollutant benzo[a]pyrene.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.11
• /
• pp.1546-1554
• /
• 2010

A bacterial strain capable of producing extracellular ${\alpha}$-galactosidase was isolated from a sample of sugarcane industrial waste. Microbiological, physiological, and biochemical studies revealed that the isolate belonged to Bacillus sp. Furthermore, based on a 16S rDNA sequence analysis, the new isolate was identified as Bacillus megaterium VHM1. The production of ${\alpha}$-galactosidase was optimized based on various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen sources, respectively. The optimum pH was 7.5 and the enzyme remained stable over a pH range of 5-9. The enzyme was optimally active at $55^{\circ}C$ and thermostable with a half-life of 120 min, yet lost 90% of its residual activity within 120 min at $60^{\circ}C$. One mM concentrations of $Ag^2$, $Cu^2$, and $Hg^{2+}$ strongly inhibited the ${\alpha}$-galactosidase, whereas the metal ions $Fe^2$, $Mn^{2+}$, and $Mg^{2+}$ had no effect on the ${\alpha}$-galactosidase activity, and $Zn^{2+}$, $Ni^{2+}$, and $Ca^{2+}$ reduced the enzyme activity slightly. When treated with the B. megaterium VHM1 enzyme, the flatulence-causing sugars in soymilk were completely hydrolyzed within 1.5 h.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.2
• /
• pp.326-336
• /
• 2016

Saccharomyces cerevisiae is one of the most employed cell factories for the production of bioproducts. Although monomeric hexose sugars constitute the preferential carbon source, this yeast can grow on a wide variety of nitrogen sources that are catabolized through central nitrogen metabolism (CNM). To evaluate the effects of internal perturbations on nitrogen utilization, we characterized strains deleted or overexpressed in GLT1, encoding for one of the key enzymes of the CNM node, the glutamate synthase. These strains, together with the parental strain as control, have been cultivated in minimal medium formulated with ammonium sulfate, glutamate, or glutamine as nitrogen source. Growth kinetics, together with the determination of protein content, viability, and reactive oxygen species (ROS) accumulation at the single cell level, revealed that GLT1 modulations do not significantly influence the cellular physiology, whereas the nitrogen source does. As important exceptions, GLT1 deletion negatively affected the scavenging activity of glutamate against ROS accumulation, when cells were treated with H₂O₂, whereas Glt1p overproduction led to lower viability in glutamine medium. Overall, this confirms the robustness of the CNM node against internal perturbations, but, at the same time, highlights its plasticity in respect to the environment. Considering that side-stream protein-rich waste materials are emerging as substrates to be used in an integrated biorefinery, these results underline the importance of preliminarily evaluating the best nitrogen source not only for media formulation, but also for the overall economics of the process.

• The Korean Journal of Mycology
• /
• v.22 no.3
• /
• pp.254-259
• /
• 1994

The ever increasing demand for energy and the shortage of resources all over the world have generated interest in recycling renewable sources such as lignocelluloses which otherwise would go to waste and cause environmental pollution. Lignin is the incrustation material for cellulose and hemicellulose, therefore, cellulose and hemicellulose are not easily degraded. Recycling lignocellulosic wastes as agricultural material are benefit to everybody and everything. In order to improve ligninase and laccase production of Phanerochaete chrysosporium, BKM-F-1767 and Ceriporiopsis subvermispora, FP 90031-SP, were compared. The ligninase activity of P. chrysosporium was maximum on day 4.5 of shaking culture at 150 rpm 2.5 cm in a back and forth cycle. The laccase activity of C. subvermispora was maximum on day 5.5 for 2% malt extract+0.1% yeast extract+0.1% Tween 20+6 mM Benzyl alcohol culture medium at stationary state.

• Journal of the Korean Society of Food Culture
• /
• v.37 no.6
• /
• pp.555-563
• /
• 2022

The purpose of this study was to confirm the quality characteristics of distilled soju with different rice pretreatment processes. The non-steamed fermentation method is a technology that uses starch to produce saccharification and alcohol without going through the steaming of raw materials. It has advantages such as reduction of manpower and cost, prevention of nutrient loss, and minimization of waste water. In this study, rice used were non-steamed and pulverized 'Baromi2', nonsteamed and steamed 'Samgwang', and puffed rice. As the fermenting agent, koji, modified nuruk, N9 yeast, and purified enzyme were used, and lactic acid was added to prevent contamination during fermentation. The amount of water was 300% in total, and after the first watering, 5 days after fermentation, the second watering was carried out. As a result of the study, it was confirmed that the non-steamed fermentation method using 'Baromi' was superior to the existing fermentation method in terms of temperature during fermentation, final alcohol content, soluble solids, and pH. By expanding the stability of the production technology of non-steamed fermentation technology, product quality improvement can be expected.

• Food Science and Preservation
• /
• v.22 no.2
• /
• pp.251-255
• /
• 2015

To optimize the medium composition of Undaria pinnatifida as a pH modulator the growth of Lactobacillus plantarum industrial scale, we analyzed the pH and growth characteristics of L. plantarum in basal medium. Subsequently, the medium compositions addition of carbon, nitrogen sources and buffering agents were optimized. When 0.5% yeast extract and 2% glucose, L. plantarum grew to maximum cell density in experimental condition. However, the growth of L. plantarum rapidly pH 4.0 in basal medium. A high alkali-ash value and low cost-effective utilization n the waste part as examined. ddition of U. pinnatifida extract alleviated the serious decrease. Among them, juice of U. pinnatifida was most helpful for the growth of L. plantarum ($36.3{\pm}1.810^8CFU/mL$). These results show that U. pinnatifida be large-scale cultivation of L. plantarum. This optimized U. pinnatifida medium can be used for safe and economical production of Lactobacillus.

• Journal of Animal Science and Technology
• /
• v.52 no.2
• /
• pp.117-124
• /
• 2010

An in situ ruminal disappearance trial and an in vivo sheep metabolism trial were conducted to evaluate the nutritional value of spent mushroom substrate (SMS, originated from Pleurotus osteratus bed-type cultivation). The raw SMS was ensiled (ESMS) for 30 days with 5% (w/w, DM basis) molasses, 0.5% (v/w) yeast (Saccharomyces cerevisiae) and 0.5% (v/w) lactic acid bacteria (Lactobacillus plantarum). Two ruminally cannulated Holsteins (average BW 620 kg) were used to evaluate in situ disappearance. Six sheeps (average BW 48 kg) were fed, in $3{\times}3$ Latin square design, rice straw alone (Control), 25% (ESMS-25) and 50% (ESMS-50) of rice straw were replaced with ensiled SMS. For an in situ trial, ruminal DM and neutral detergent fiber (NDF) disappearance of SMS were increased after ensiling (P<0.05). For a sheep trial, protein and fiber (NDF, acid detergent fiber, crude fiber) digestibilities were decreased (P<0.05), crude ash digestibility was increased (P<0.001), and nitrogen retention was not affected (P>0.05) as rice straw was replaced with ensiled SMS. Ruminating time was decreased by an average of 28% by feeding ensiled SMS (P<0.05). Ensiled SMS (Bed-type cultivation) had 76% of energy value of rice straw. Consequently, ensiled SMS (Bed-type cultivation, 100% cotton waste) could be used as a roughage source appropriate for maintenance type rations for ruminants.