• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.132-135
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• 1997

We prepared capsules containing Saccharomyces cerevisiae and Zoogloea ramigera cells for the removal of lead(II) and cadmium ions. Microbial cells were encapsulated and cultured in the growth medium. The S.cerevisiae cells grown in the capule did not leak through the capsule membrane. The dried cell density reached to 250 g/l on the basis of the inner volume of the 2.0 mm diameter capsule after 36 hour cultivation. The dry whole cell expolymer density of encapsulated Z.ramigera reached to 200 g/L. The capsule was crosslinked with triethylene tetramine and glutaric dialdehyde solutions. The cadmium uptake of encapsulated whole cell expolymer of Z.ramigera was 55mg Cd/g biosorbent. The adsorption line followed well Langmuir isotherm. The lead uptake of the encapsulated S. cerevisiae was about 30 mg Pb/g biomass. The optimum pH of the lead uptake using encapsulated S. cerevisiae was found to be 6. Freundlich model showed a little better fit to the adsorption data than Langmuir model 95 percent of the lead adsorbed on the encapsulated biosorbents was desorbed by the 1 M HCl solution. The capsule was reused 50 batches without loosing the metal uptake capacity. And the mechanical strength of the crosslinked capsule was retained after 50 trials.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.511-517
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• 2016

Scabraside D, a sulfated triterpene glycoside extract from sea cucumber Holothulia scabra, shows various biological activities, but effects on human cholangiocarcinoma cells have not previously been reported. In the present study, we investigated the activity of scabraside D against human cholangiocarcinoma (HuCCA) both in vitro and for tumor growth inhibition in vivo using a xenograft model in nude mice. Scabraside D ($12.5-100{\mu}g/mL$) significantly decreased the viability and the migration of the HuCCA cells in a dose-dependent manner, with 50% inhibitory concentration (IC50) of $12.8{\pm}0.05{\mu}g/mL$ at 24 h. It induced signs of apoptotic cells, including shrinkage, pyknosis and karyorrhetic nuclei and DNA fragmentation on agarose gel electrophoresis. Moreover, by quantitative real-time PCR, scabraside D effectively decreased Bcl-2 while increasing Bax and Caspase-3 gene expression levels suggesting that the scabraside D could induce apoptosis in HuCCA cells. In vivo study demonstrated that scabraside D (1 mg/kg/day, i.p. for 21 days) significantly reduced growth of the HuCCA xenografts without adverse effects on the nude mice. Conclusively, scabraside D induced apoptosis in HuCCA cells and reduced the growth of HuCCA xenographs model. Therefore, scabraside D may have potential as a new therapeutic agent for cholangiocarcinoma.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6709-6714
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• 2013

Background: Breast cancer is a leading cause of death in women. The available chemotherapy drugs have been associated with many side effects. Bromelain has novel medicinal qualities including anti-inflammatory, anti-thrombotic, fibrinolytic and anti-cancer functions. Commercially available bromelain is obtained through tedious methods; therefore, recombinant bromelain may provide a cheaper and simpler choice with similar quality. Materials and Methods: This study aimed to assess the effects of commercial and recombinant bromelain on the cytokinetic behavior of MCF-7 breast cancer cells and their potential as therapeutic alternatives in cancer treatment. Cytotoxic activities of commercial and recombinant bromelain were determined using (sulforhodamine) SRB assay. Next, cell viability assays were conducted to determine effects of commercial and recombinant bromelain on MCF-7 cell cytokinetic behavior. Finally, the established growth kinetic data were used to modify a model that predicts the effects of commercial and recombinant bromelain on MCF-7 cells. Results: Commercial and recombinant bromelain exerted strong effects towards decreasing the cell viability of MCF-7 cells with $IC_{50}$ values of 5.13 ${\mu}g/mL$ and 6.25 ${\mu}g/mL$, respectively, compared to taxol with an $IC_{50}$ value of 0.063 ${\mu}g/mL$. The present results indicate that commercial and recombinant bromelain both have anti-proliferative activity, reduced the number of cell generations from 3.92 to 2.81 for commercial bromelain and to 2.86 for recombinant bromelain, while with taxol reduction was to 3.12. Microscopic observation of bromelain-treated MCF-7 cells demonstrated detachment. Inhibition activity was verified with growth rates decreased dynamically from 0.009 $h^{-1}$ to 0.0059 $h^{-1}$ for commercial bromelain and to 0.0063 $h^{-1}$ for recombinant bromelain. Conclusions: Commercial and recombinant bromelain both affect cytokinetics of MCF-7 cells by decreasing cell viability, demonstrating similar strength to taxol.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.83-87
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• 2014

The effects of combined treatment of aqueous chlorine dioxide ($ClO_2$) and fumaric acid on the microbial growth in fresh-cut paprika were investigated. After the combined treatment, the populations of total aerobic bacteria and inoculated Listeria monocytogenes in the paprika sample were reduced by 0.82 and 1.21 log CFU/g, respectively, compared to those of the control. In addition, after 10 d of storage at $10^{\circ}C$, the populations were decreased by 1.21 and 2.10 log CFU/g, respectively. The predictive model for the populations of total aerobic bacteria and L. monocytogenes in the paprika was applied during storage. The prediction equation using Gompertz model was appropriate, based on the statistical analysis such as accuracy factor and bias factor. These results suggest that the combined treatment of aqueous $ClO_2$ and fumaric acid can be an effective technology for microbial decontamination and it can improve microbial safety by decreasing maximum growth rate and increasing lag time of bacteria in the fresh-cut paprika.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.348-355
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• 2002

To know characteristics of water quality in Saemankeum area, we were investigated the water quality of surface layer from July of 1999 to June of 2000. The concentrations of COD and chlorophyll a were in the range of $0.64\~6.40$ (mean 1.96)mg/L, $1.95\~51.55$ (mean 11,07)$mg/m^3$, respectively. The annual mean concentrations of DIN, DIP were found to be 21.182 $\mu$g-at/L and 0,655 $\mu$g-at/L respectively, which were exceeding second grade of seawater quality standard. The nitrogen ratio to the phosphorus was lower than 1. Therefore, nitrogen was playing an important role in phytoplankton growth as limiting factor in study area. Mean values of eutrophication index were exceeding 1, which was the eutrophication criteria. Especially Mankyung and Dongjin estuary were shown over 10 as eutrophication index. Therefore, Saemankeum area could be evaluated to possibility area for eutrophication. Released rate for ammonia nitrogen and phosphate phosphorus from sediments were 62.92 ${\mu}g-at/m^3/hr$ and 6.71 ${\mu}g-at/m^3/hr$, respectively.

• Journal of Aquaculture
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• v.15 no.3
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• pp.123-129
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• 2002

In Nam-myeon coastal area of southern sea, Korea, the following hydrobiological conditions prevailed during 1997: water temperature: 12.6 ~24.5 $^{\circ}C$ ; Salinity: 27.32 ~33.$10 \textperthousand$, Dissolved oxygen: 7.05 $ml/L$ and Chlorophyll a: 1.69 ~ 7.40 $\mu $/L. Phytoplankton, dominated by Ceratium sp, peaked during June-July. Mean growth rates of the bay scallop of selected and non-selected groups cultured for 185 days in this area from July to December, 1997 were 0.17 and 0.19 mm/day for shell height, and 0.17 and 0.16 g/day for total weight, respectively. Maximum predicted values of shell height, calculated by von Bertalanffy growth model, were 54.98 mm for the selected and 52.62 mm for the non-selected groups. Survival of the selected and non-selected groups was 80.0 and 87.0%, respectively.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.587-592
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• 2005

Hydrolyzates from lignocellulosic biomass contain a mixture of simple sugars; the predominant ones being glucose, cellobiose and xylose. The fermentation of such mixtures to ethanol or other chemicals requires an understanding of how each of these substrates is utilized. Candida lusitaniae can efficiently produce ethanol from both glucose and cellobiose and is an attractive organism for ethanol production. Experiments were performed to obtain kinetic data for ethanol production from glucose, cellobiose and xylose. Various combinations were tested in order to determine kinetic behavior with multiple carbon sources. Glucose was shown to repress the utilization of cellobiose and xylose. However, cellobiose and xylose were simultaneously utilized after glucose depletion. Maximum volumetric ethanol production rates were 0.56, 0.33, and 0.003 g/L h from glucose, cellobiose and xylose, respectively. A kinetic model based on cAMP mediated catabolite repression was developed. This model adequately described the growth and ethanol production from a mixture of sugars in a batch culture.

• Ocean and Polar Research
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• v.43 no.2
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• pp.89-98
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• 2021

The seagrass habitats are a highly productive marine ecosystem which provides nursery ground and shelter for many fish and invertebrate species. Pholis nebulosa (Temminck & Schlegel, 1845) is one of the most abundant seagrass fishes in the coastal waters of Korea. The estimation of fish production is key for devising conservation measures and ensuring fish resources sustainability. A total 894 P. nebulosa ranging from 3.83 to 26.5 cm total length (TL) were collected monthly in 2006 with a small beam trawl in a seagrass bed of southern Korea. Growth parameters of P. nebulosa were estimated using the von Bertalanffy growth model, and production was estimated using a general equation which relates daily fish production to ash-free dry weight (AFDW), biomass, and water temperature. The von Bertalanffy's growth equation was estimated as: L_t = 28.3823(1-e^{-0.7835(t+0.9864)}). The densities, biomass, daily, annual production, and P/B ratio were 0.069±0.061/m^-2, 1.022±0.621 g/m², 0.005±0.004 g AFDW/m²/day, 1.676 g AFDW/m²/yr, and 1.641, respectively. Monthly variation in production of P. nebulosa peaked during March and April 2006 (0.0139 and 0.0111 g AFDW/m²/day), whereas the lowest value of 0.0005 g AFDW/m²/day was in December. Monthly change in production of P. nebulosa was positively correlated with biomass and condition factor. Our results will contribute to the conservation of seagrass ecosystems, which are still undisturbed in the study area.

• ALGAE
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• v.17 no.3
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• pp.187-194
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• 2002

A seaweed biofilter/production system of being developed to reduce the environmental impact of marine fish farm effluent in coastal ecosystems as a part of an integrated aquaculture system. Several known seaweed taxa and their cultivars have been considered as candidate biofilter organisms based on their species-specific physiological properties such as nutrient uptake kinetics and their economic value. Porphyra is an excellent cadidate and shows efficient nutrient extraction properties. Rates of ammonium uptake were maintained at around 3 ${\mu}moles{\cdot}g{\cdot}dw^{-1}{\cdot}min^{-1}$ at 150 ${\mu}M$ inorganic nitrogen at $10^{\circ}C$. Ulva is another possible biofilter candidate with an uptake rate of 1.9 ${\mu}moles{\cdot}g{\cdot}dw^{-1}{\cdot}min^{-1}$ under same conditions. A simple uptake/growth and harvest model was applied to estimate the efficiency of the biofilter/production system. The model was deterministic and used a compartment model structure based on difference equations. The efficiency of Porpyra filter was estimated over 17% of ${NH_4}^+$ removal from the contimuous supply of 100 ${\mu}mole{\cdot}l^{-1}\;{NH_4}^+\;at\;100l{\cdot}sec^{-1}$ flow rate.

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1238-1249
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• 2023

In this study, we sought to investigate the production and optimization of biosurfactants by soil fungi isolated from petroleum oil-contaminated soil in Saudi Arabia. Forty-four fungal isolates were isolated from ten petroleum oil-contaminated soil samples. All isolates were identified using the internal transcribed spacer (ITS) region, and biosurfactant screening showed that thirty-nine of the isolates were positive. Aspergillus niger SA1 was the highest biosurfactant producer, demonstrating surface tension, drop collapsing, oil displacement, and an emulsification index (E₂₄) of 35.8 mN/m, 0.55 cm, 6.7 cm, and 70%, respectively. This isolate was therefore selected for biosurfactant optimization using the Fit Group model. The biosurfactant yield was increased 1.22 times higher than in the nonoptimized medium (8.02 g/l) under conditions of pH 6, temperature 35℃, waste frying oil (5.5 g), agitation rate of 200 rpm, and an incubation period of 7 days. Model significance and fitness analysis had an RMSE score of 0.852 and a p-value of 0.0016. The biosurfactant activities were surface tension (35.8 mN/m), drop collapsing (0.7 cm), oil displacement (4.5 cm), and E₂₄ (65.0%). The time course of biosurfactant production was a growth-associated phase. The main outputs of the mathematical model for biomass yield were Yx/s (1.18), and µ_max (0.0306) for biosurfactant yield was Y_p/s (1.87) and Y_p/x (2.51); for waste frying oil consumption the So was 55 g/l, and Ke was 2.56. To verify the model's accuracy, percentage errors between biomass and biosurfactant yields were determined by experimental work and calculated using model equations. The average error of biomass yield was 2.68%, and the average error percentage of biosurfactant yield was 3.39%.