• Journal of Microbiology and Biotechnology
• /
• v.24 no.4
• /
• pp.453-464
• /
• 2014

The current research was focused on the extracellular biosynthesis of bactericidal silver nanoparticles (AgNPs) using cell-free supernatant of a local isolate previously identified as a novel Streptomyces aegyptia NEAE 102. The biosynthesis of silver nanoparticles by Streptomyces aegyptia NEAE 102 was quite fast and required far less time than previously published strains. The produced particles showed a single surface plasmon resonance peak at 400 nm by UV-Vis spectroscopy, which confirmed the presence of AgNPs. Response surface methodology was chosen to evaluate the effects of four process variables ($AgNO_3$ concentration, incubation period, pH levels, and inoculum size) on the biosynthesis of silver nanoparticles by Streptomyces aegyptia NEAE 102. Statistical analysis of the results showed that the linear and quadratic effects of incubation period, initial pH, and inoculum size had a significant effect (p < 0.05) on the biosynthesis of silver nanoparticles by Streptomyces aegyptia NEAE 102. The maximum silver nanoparticles biosynthesis (2.5 OD, at 400 nm ) was achieved in runs number 5 and 14 under the conditions of 1 mM $AgNO_3$ (1-1.5% (v/v)), incubation period (72-96 h), initial pH (9-10), and inoculum size (2-4% (v/v)). An overall 4-fold increase in AgNPs biosynthesis was obtained as compared with that of unoptimized conditions. The biosynthesized silver nanoparticles were characterized using UV-VIS spectrophotometer and Fourier transform infrared spectroscopy analysis, in addition to antimicrobial properties. The biosynthesized AgNPs significantly inhibited the growth of medically important pathogenic gram-positive (Staphylococcus aureus) and gram-negative bacteria (Pseudomonas aeruginosa) and yeast (Candida albicans).

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.11 no.6
• /
• pp.530-537
• /
• 2006

Recently isolated, Pseudomonas putida SN1 grows on styrene as its sole carbon and energy source through successive oxidation of styrene by styrene monooxygenase (SMO), styrene oxide isomerase (SOI), and phenylacetaldehyde dehydrogenase. For the production of (S)-styrene oxide, two knockout mutants of SN1 were constructed, one lacking SOI and another lacking both SMO and SOI. These mutants were developed into whole-cell biocatalysts by transformation with a multicopy plasmid vector containing SMO genes (styAB) of the SN1. Neither of these self-cloned recombinants could grow on styrene, but both converted styrene into an enantiopure (S)-styrene oxide (e.e. > 99%). Whole-cell SMO activity was higher in the recombinant constructed from the SOI-deleted mutant (130 U/g cdw) than in the other one (35 U/g cdw). However, the SMO activity of the former was about the same as that of the SOI-deleted SN1 possessing a single copy of the styAB gene that was used as host. This indicates that the copy number of styAB genes is not rate-limiting on SMO catalysis by whole-cell SN1.

• Microbiology and Biotechnology Letters
• /
• v.46 no.4
• /
• pp.390-394
• /
• 2018

For the coexpression of endoxylanase and endoglucanase genes in yeast Saccharomyces cerevisiae, the genes were separately inserted downstream of the yeast ADH1 promoters, resulting the plasmid pAGX3 (9.83 kb). In the batch culture on YPD medium of the yeast transformant, S. cerevisiae SEY2102/pAGX3, the total activities of the enzymes reached about 7.91 units/ml for endoxylanase and 0.43 units/ml for endoglucanase. In the fed-batch culture with intermittent feeding of yeast extract and glucose, the total activities of 24.9 units/ml for endoxylanase and 0.84 units/ml for endoglucanase were produced which were about 3.1-fold and 2.0-fold increased levels, respectively, compared to those of the batch culture. Most of endoxylanase and endoglucanase activities were found in the extracellular media. This recombinant yeast could be useful for the development of simultaneous saccharification bioprocess of the cellulose and xylan mixture.

• Fisheries and Aquatic Sciences
• /
• v.25 no.8
• /
• pp.450-461
• /
• 2022

A randomized, double-blind, and placebo-controlled clinical study was used to determine the cognitive functions related to working memory (WM) and antioxidant properties of fermented Laminaria japonica (FLJ) on healthy volunteers. Eighty participants were divided into a placebo group (n = 40) and FLJ group (n = 40) that received FLJ (1.5 g/day) for 6 weeks. Memory-related blood indices (brain-derived neurotrophic factor, BDNF; angiotensin-converting enzyme; human growth hormone, HGH; insulin-like growth factor-1, IGF-1) and antioxidant function-related indices (catalase, CAT; malondialdehyde, MDA; 8-oxo-2'-deoxyguanosine, 8-oxo-dG; thiobarbituric acid reactive substances, TBARS) were determined before and after the trial. In addition, standardized cognitive tests were conducted using the Cambridge Neuropsychological Test Automated Batteries. Furthermore, the Korean Wechsler Adult Intelligence Scale (K-WAIS)-IV, and the Korean version of the Montreal Cognitive Assessment (MoCA-K) were used to assess the pre and post intake changes on WM-related properties. According to the results, FLJ significantly increased the level of CAT, BDNF, HGH, and IGF-1. FLJ reduced the level of TBARS, MDA, and 8-oxo-dG in serum. Furthermore, FLJ improved physical activities related to cognitive functions such as K-WAIS-IV, MoCA-K, Paired Associates Learning, and Spatial Working Memory compared to the placebo group. Our results suggest that FLJ is a potential candidate to develop functional materials reflecting its capability to induce antioxidant mechanisms together with WM-related indices.

• KSBB Journal
• /
• v.24 no.6
• /
• pp.495-507
• /
• 2009

As we move into the 21st century, the importance of marine resources is certain to increase due to the accelerated exhaustion of land resources. For the sustainable development of the world, therefore, we need to develop marine chemical bioindustries which enable us to produce industrial chemicals, advanced materials, fuels, and minerals from marine resources such as seaweeds and seawater. In this review, we selected five marine chemical bioindustries which include 1) seaweed polysaccharide industry, 2) marine advanced materials industry, 3) marine biofuel industry, 4) marine sea salt industry, and 5) deep-sea water industry, and discussed the current status and future prospects of each industry sector. It has been assessed that the future of marine chemical bioindustry looks very promising although there are many needs for more intensive research investments on marine bioprocess development through close cooperation between marine biologists and biochemical engineers.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.25 no.2
• /
• pp.12-19
• /
• 2023

This study conducted an experiment with EC 1.0ms/cm ratio and excellent soil conditions for germination in ICT-based ginseng process cultivation. The first growth survey was conducted before transplantation of ginseng 1-year roots grown by seeding ginseng in the process cultivation, conventional cultivation and a second growth comparison survey was conducted after 3 months of growth. In the results, it was confirmed that ginseng grown in the process cultivation grew more than in the field. As a result of comparing the contents of 11 ginsenosides of 1-year and 2-year-old ginsenosides in the process cultivation and conventional cultivation ginseng, it was confirmed that the content of the process cultivation ginseng was higher than that of practice cultivation ginseng. In conclusion, conventional cultivation ginseng grows due to various factors under the natural cultivation environment, but process cultivation can secure the growth stability of ginseng by allowing stable soil and environmental control, so continuous research is needed in the future.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.8 no.2
• /
• pp.151-157
• /
• 2003

Obtaining a sufficient amount of healthy keratinocytes from a small tissue is difficult. However, ORS cells can be a good source of epithelium since they are easily obtainable and patients do not have to suffer from scar formation at donor sites. Accordingly, the current study modified the conventional primary culture technique to overcome the low propagation and easy aging of epithelial cells during culturing. In a conventional primary culture, the average yield of human ORS tells is 2.↑ $\times$ 10$^3$cells/follicle based on direct incubation in a trypsin (0.1%)/EDTA(0.02%) solution for 15 min at 37$^{\circ}C$, however, our modified method was able to obtain about 6.9 $\times$ 10$^3$cel1s/follicle using a two-step enzyme digestion method involving dispase (1.2 U/mL) and a trypsin (0.1%)/EDTA (0.02%) solution. Thus, the yield of primary cultured ORS cells could be increasd three times higher. Furthermore, a total of 2.0 $\times$ 10$^{7}$ cells was obtained in a serum-free medium. while a modified E-medium with mitomycin C-treated feeder tells produced a total of 6.3 $\times$ 10$^{7}$ Cel1s over 17 days When Starting With 7.5 $\times$ 10$^4$cells. Finally, We Confirmed the effectiveness of our ORS tell isolation method by presenting their ability for reconstructing the bioartificial skin epithelium in vitro

• KSBB Journal
• /
• v.17 no.6
• /
• pp.525-530
• /
• 2002

The optimum culture conditions for tropane alkaloid production in hairy root cultures of Korea native Scopolia paviflora Nak. were investigated. Hairy root was induced from the rhizome of the mother plant on B5 medium containing 1.0 mg/L IBA. Among the culture media examined, 1/2 B5 medium was the best for tropane alkaloid production, whereas the growth of hairy root increased in SH medium. The best result on the growth of hairy root was obtained in 1.0 mg/L NAA, and tropane alkaloid production was obtained in plant growth regulator-free medium. Of the carbone sources tested, 3% sucrose promoted the growth of hairy root, whereas 5% sucrose increased tropane alkaloid production. Optimum inoculum densities for root growth and tropane alkaloid production were 0.5 g and 1 g, respectively. The addition of XAD resins (1 % w/v) to hairy root cultures led to increases in tropans alkaloid production, and the release of alkaloid into the medium and its adsorption by the resin accounted for about 50 to 80％ of total production. It is concluded that optimized culture conditions and the addition of XAD resins could be used in the development of a bioprocess for tropane alkaloid production in hairy root cultures of S. paviflora Nak.

• Nutrition Research and Practice
• /
• v.12 no.3
• /
• pp.199-207
• /
• 2018

BACKGROUND/OBJECTIVES: Fermented Laminaria japonica (FL), a type sea tangle used as a functional food ingredient, has been reported to possess cognitive improving properties that may aid in the treatment of common neurodegenerative disorders, such as dementia. MATERIALS/METHODS: We examined the effects of FL on scopolamine (Sco)- and ethanol (EtOH)-induced hippocampus-dependent memory impairment, using the Passive avoidance (PA) and Morris water maze (MWM) tests. To examine the underlying mechanisms associated with neuroprotective effects, we analyzed acetylcholine (ACh) and acetylcholinesterase (AChE) activity, brain tissue expression of muscarinic acetylcholine receptor (mAChR), cAMP response element binding protein (CREB) and extracellular signal-regulated kinases 1/2 (ERK1/2), and immunohistochemical analysis, in the hippocampus of mice, compared to current drug therapy intervention. Biochemical blood analysis was carried out to determine the effects of FL on alanine transaminase (ALT), aspartate transaminase (AST), and triglyceride (TG) and total cholesterol (TC) levels. 7 groups (n = 10) consisted of a control (CON), 3 Sco-induced dementia and 3 EtOH-induced dementia groups, with both dementia group types containing an untreated group (Sco and EtOH); a positive control, orally administered donepezil (Dpz) (4mg/kg) (Sco + Dpz and EtOH + Dpz); and an FL (50 mg/kg) treatment group (Sco + FL50 and EtOH + FL50), orally administered over the 4-week experimental period. RESULTS: FL50 significantly reduced EtOH-induced increase in AST and ALT levels. FL50 treatment reduced EtOH-impaired step-through latency time in the PA test, and Sco- and EtOH-induced dementia escape latency times in the MWM test. Moreover, anticholinergic effects of Sco and EtOH on the brain were reversed by FL50, through the attenuation of AChE activity and elevation of ACh concentration. FL50 elevated ERK1/2 protein expression and increased p-CREB (ser133) in hippocampus brain tissue, according to Western blot and immunohistochemistry analysis, respectively. CONCLUSION: Overall, these results suggest that FL may be considered an efficacious intervention for Sco- and EtOH-induced dementia, in terms of reversing cognitive impairment and neuroplastic dysfunction.