• Textile Coloration and Finishing
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• v.28 no.3
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• pp.134-155
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• 2016

Perfluorinated chemicals are highly diverse and widely used. More than 160 substances are pre-registered under REACH and approximately 140 substances are in the existing chemicals list of Korea from this chemical group. Chemical structures of PFCs that are globally prohibited and still in uses are identified with OECD's classification of PFCs with an overall review on their uses in consumer products including textile products. Case examples for current domestic situation on use of PFCs as a major component of water-repelling agents in textile products as well as a brief summary of eight major PFC manufacturers' situation are presented from our survey study along the supply chains and the most recent report of EPA stewardship programme, respectively.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.24-29
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• 2000

Yoqurt products are known to be effective for enhancing health and preventing diseases such as cancers. Such effects are generally believed to be due to actions of polysacchmides in yoqurt products. In this study we have determined compositions of monosaccharides in hydrolysates of commercial yoqrtrt products as the first step of understanding structures of polysaccharides. The yoqtrrt products were ttltracentrifuged, filtered, hydrolyzed in 1M sulfuric acid and neutralized. A portion of the solution was taken and evaporated to dryness, denvatized with TMSI (trimethly- silylimidazole) and analyzed by GC/MS. We found that the monosaccharides were fructose, glucose, and galactose. Their compositions were variant among several yoqtrrt products.

• Journal of Dairy Science and Biotechnology
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• v.29 no.2
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• pp.51-57
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• 2011

Milk and dairy products are nutritionally one of the most important food in human health and the quality of raw milk is significantly important to ensure safety of dairy products. However, milk and dairy products are commonly related with chemical and microbial contaminations. Therefore, rapid and reliable detection of hazardous (e.g. pathogenic bacteria, pesticides, antibiotics, microbial toxins) in milk and dairy products is essential to ensure human health and food safety. Conventional methods for detection of food hazardous are mostly time-consuming to yield a results. Recently, biosensors have been focused as its rapidity and high sensitivity to analyse chemical and microbial hazardous from a variety of foods and environments. This study reviewed the recent trends and applications of biosensors as rapid detection method of hazardous in milk and dairy products.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.668-674
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• 2005

It is reported that a method for the hydrogen production from the propane decomposition using carbon black as a catalyst is more effective than from the methane decomposition. Since the by-products like CO and $CO_2$ are not produced by the direct decomposition of propane, it is considered as an environmentally sustainable process. In this study, hydrogen was produced by the direct decomposition of propane using either commercial activated carbon or carbon black at atmospheric pressure in the temperature range of $500-1,000^{\circ}C$. Resulting products in our experiment were not only hydrogen but also several by-products such as methane, ethylene, ethane, and propylene. Hydrogen yield increased as temperature increased because the amount of those by-products produced in the experiment was inversely proportional to temperature. The achieved hydrogen yield at $750^{\circ}C$ with commercial DCC N330 catalyst was 22.47％ in this study.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.200-208
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• 2017

Actinobacteria are prolific producers of a large number of natural products with diverse biological activities. In the present study, an actinobacterium isolated from sunflower rhizosphere soil sample collected from Medak, Andhra Pradesh, South India was identified as Amycolatopsis thermoflava strain SFMA-103. A pigmented secondary metabolite in culture broth was extracted by using methanol and it was further purified by silica gel column chromatography with methanol-chloroform solvent system. Structural elucidation studies based on UV-visible, 1D and 2D-NMR, FT-IR, and mass spectroscopic analyses confirmed the structure as 1-methoxy-3-methyl-8-hydroxy-anthraquinone. It showed significant in vitro anticancer activity against lung cancer and lymphoblastic leukemia cells with $IC_{50}$ values of 10.3 and $16.98{\mu}M$, respectively. In addition, 1-methoxy-3-methyl-8-hydroxy-anthraquinone showed good free radical scavenging activity by DPPH method with an $EC_{50}$ of $18.2{\mu}g/ml$. It also showed other promising superoxide radical scavenging, nitric oxide radical scavenging and inhibition of lipid peroxidation activities. This is a first report of anti-proliferative and antioxidant activities of 1-methoxy-3-methyl-8-hydroxy-anthraquinone isolated from A. thermoflava strain SFMA-103 which may find potential application in biotechnological and pharmaceutical fields.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.481-494
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• 2020

Objectives: No study has been conducted to review characteristics of humidifier disinfectants (HD) products, such as real numbers, levels and types of HD substances contained, or the volume marketed. We aimed to review the characteristics of HD through a literature review. Methods: We collected literature reporting the names, numbers, and ingredients of HD and discussed them with a focus on the number of HD products and the chemicals used as a disinfectant. Results: A total of eight publications has reported the names of HD brands or types of disinfectants from 2011 to 2020. To date, a total of 40 HD products have been used, excluding four products. Eight HD products used polyhexamethylene guanidine phosphate (PHMG) and 14 used a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) as disinfectants. Benzalkonium chloride (BKC) and sodium dichloroisocyanurate (NaDCC) were also used as a disinfectant in several HD products. A total of 19 HD products were associated with the development of HD associated lung injury (HDLI). The Oxy Saksak HD product containing PHMG showed the highest number of HD associated health effects. The type of disinfectant from a total of 14 HD products has not been identified. Conclusions: A total of 40 HD products have been marketed in South Korea since 1994. Further studies should be conducted to identify the association of product characteristics, including type of HD ingredients, with health effects.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.358-373
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• 2013

In this study, both mild acid and alkali treatments with 1.0 wt% and 2.0 wt% of $H_2SO_4$ and NaOH solution were applied to evaluate the effects on chemical compositions of wood biomass. Yellow poplar (Liriodendron tulipifera L.) and larch (Larix kaempferi C.) were chosen due to major species planted in Korea. Chemical treatments of biomass were carried out by being soaked in either acid or alkali solution with 1:20 ratio for 72 hours at ambient temperature. Afterward, lignin, 5 major reduced sugars, ash contents and elemental composition were determined. To statistically understand the relationship between samples and chemical treatments, the Tukey test, simple linear regression model and ANOVA analysis were introduced using a statistical software R. As results from both wet chemistry and statistical analysis, yellow poplar was more affected on the lignin and xylose contents by acid treatments under these experimental conditions. Meanwhile, larch was more affected on the composition of galactose and lignin by alkali treatments. A series of results in this study would show that equivalent chemical treatment makes a change the chemical composition of each species.

• Bulletin of the Korean Chemical Society
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• v.12 no.1
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• pp.57-60
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• 1991

Benzosilacyclobutenes were prepared from the reactions of 1,1-dichlorobenzosilacyclobutene with Grignard reagents or t-butyllithium. In the thermal reactions with alcohols, benzosilacyclobutenes underwent both benzyl-silicon and aryl-silicon bond rupture to yield (dialkyl)alkoxy-o-tolylsilanes and (dialkyl)alkoxybenzylsilanes, respectively. The photochemical reactions, however, produced only the former products via o-silaquinone methides.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.462-471
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• 2021

Background: The number of synthesized chemicals has rapidly increased over the past decade. For many chemicals, there is a lack of information on toxicity. With the current movement toward reducing animal testing, the use of toxicity big data and deep learning could be a promising tool to screen potential toxicants. Objectives: This study identified potential chemicals related to reproductive and estrogen receptor (ER)-mediated toxicities for 1135 cleaning products and 886 laundry products. Methods: We listed chemicals contained in cleaning and laundry products from a publicly available database. Then, chemicals that potentially exhibited reproductive and ER-mediated toxicities were identified using the European Union Classification, Labeling and Packaging classification and ToxCast database, respectively. For chemicals absent from the ToxCast database, ER activity was predicted using deep learning models. Results: Among the 783 listed chemicals, there were 53 with potential reproductive toxicity and 310 with potential ER-mediated toxicity. Among the 473 chemicals not tested with ToxCast assays, deep learning models indicated that 42 chemicals exhibited ER-mediated toxicity. A total of 13 chemicals were identified as causing reproductive toxicity by reacting with the ER. Conclusions: We demonstrated a screening method to identify potential chemicals related to reproductive and ER-mediated toxicities utilizing chemical toxicity big data and deep learning. Integrating toxicity data from in vivo, in vitro, and deep learning models may contribute to screening chemicals in consumer products.

• Mycobiology
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• v.51 no.4
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• pp.246-255
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• 2023

Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3β,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC₅₀ values of 2.89, 18.51, and 16.47 ㎍/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37±1.35% at 25 ㎍/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.