• Journal of Life Science
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• v.4 no.3
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• pp.92-101
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• 1994

With the rapid development of bioorganic chemistry recently, a field of artificial enzymes has a great concern from the industrial point of view. A number of possibilities now exist ofr the construction of artificial enzymes. They must posses two structural entities, a substrate-binding site and a catalytically effective site. It has been found that producing the facility for substrate binding is relatively straightforward but catalytic sites are somewhat more difficult. Therefore, synthetic catalysts do not yet match all the properties of an enzyme, however, the design of catalysts has lead to very powerful effects. This article reviews the existing literature on the modeling of artificial enzymes using cyclodextrin, modified cyclodextrin and crown compounds.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.77-83
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• 2017

Lignocellulosic biomass represents a potentially large resource to supply the world's fuel and chemical feedstocks. Enzymatic bioconversion of this substrate offers a reliable strategy for accessing this material under mild reaction conditions. Owing to the complex nature of lignocellulose, many different enzymatic activities are required to function in concert to perform efficient transformation. In nature, large multienzyme complexes are known to effectively hydrolyze lignocellulose into constituent monomeric sugars. We created artificial complexes of enzymes, called rosettazymes, in order to hydrolyze glucuronoxylan, a common lignocellulose component, into its cognate sugar ${\small{D}}$-xylose and then further convert the ${\small{D}}$-xylose into ${\small{D}}$-xylonic acid, a Department of Energy top-30 platform chemical. Four different types of enzymes (endoxylanase, ${\alpha}$-glucuronidase, ${\beta}$-xylosidase, and xylose dehydrogenase) were incorporated into the artificial complexes. We demonstrated that tethering our enzymes in a complex resulted in significantly more activity (up to 71%) than the same amount of enzymes free in solution. We also determined that varying the enzyme composition affected the level of complex-related activity enhancement as well as overall yield.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1911-1920
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• 2005

Effective artificial metalloproteases have been designed by using cross-linked polystyrene as the backbone. Artificial active sites comprising Cu(II) complexes as the catalytic site and other metal centers or organic functionalities as binding sites were synthesized. The activity of Cu(II) centers for peptide hydrolysis was greatly enhanced on attachment to polystyrene. By placing binding sites in proximity to the catalytic centers, the ability to hydrolyze a variety of protein substrates at selected cleavage sites was improved. Thus far, the most advanced immobile artificial proteases have been obtained by attaching the aldehyde group in proximity to the Cu(II) complex of cyclen.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.13-19
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• 2005

Biotechnological researches in Central Asian Research Institute of Sericulture were developed since 1981 when laboratory of artificial diets for mulberry silk­worm was created. The researches were directed not only to creation of accessible artificial diets (AD) for off-season mass rearing of economical beneficial insect and for industrialization of sericulture but also to obtaining of easy reproducible source of animal proteins, carbohydrates, lipids, enzymes, enzymes inhibitors and other metabolites - bioresource for manufacture of oriental medicine preparations. Space experiments with silkworms became possible with use of AD. These experiments used mulberry silkworm as high effective board test organism with outstanding developmental, reproductive and transgenic properties having impor­tant significance in future of cosmonautics. Introduction to practice of bioprotective and ecologically pure method of drying and sterilizing of green cocoons and by-products of silk manufacture allows to increase efficiency of cocoons reeling technology as well as to preserve nativity of biological active substances in mulberry silkworm pupae that is unachievable by traditional methods of raw material processing. New spheres of application of two important silk proteins - fibroin and sericin in medicine, cosmetics, for bio- and nanotechnology are opening with use of biotechnological approaches. At present the achievements and experience of R & D in these fields are used in creation of modern pests biocontrol agents. Schemes of efficient processing of cocoon raw material, by-products and wastes of sericulture and cocoon processing are devel- Institute of Physiology and Biophysics, Uzbek Academy of Sciences, I, Niyazov street, 700095, Tashkent, Uzbekistan. oped for obtaining of traditional and new consumer products.

• Journal of Nutrition and Health
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• v.36 no.1
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• pp.32-39
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• 2003

Phytoestrogens, especially soy-derived isoflavones, are receiving great scrutiny as a food supplement for preventing hormone dependent disease such as postmenopausal osteoporosis. Their beneficial effects are derived from aglycone form of isoflavones, such as daidzein, genistein or glycitein. In contrast to the common usage of soybean, black bean (Rhynchosia Molubilis : Yak-kong) has been used as a supplement for preventing postmenopausal osteoporosis in oriental medicine. To investigate the effects of the saliva, artificial stomach fluid, and digestive enzymes on the conversion of glycosidic isoflavone to aglycone form, soybean and black bean were extracted with 70% methanol and freeze-dried. The recovery yield of methanol extracts of black bean was 14.1% which was higher than that of soybean, 13.5%. In terms of total isoflavones, we routinely obtained larger amount of isoflavones from black bean than those from soybean. By incubating methanol extracts of soybean and black bean with IN HCI for 180 min, the proportions of aglycones relative to the total isoflavone were significantly increased (32.4% and 52.4%, respectively). In vitro conversion, digestive enzymes ($\beta$-glucosidase and $\alpha$-glucosidase) may hydrolyze glycosidic bond of isoflavone more effectively than saliva or artificial stomach fluid did. It seems to say that the activity of $\beta$-glucosidase was higher than those of $\alpha$-glucosidase. The rate of conversion of glucoside form to aglycone form in black bean and soybean was low in physiological condition (pH) tested, although the enzymatic hydrolysis of glucoside was active. These results demonstrated that the composition of aglycone in food may be the important factors in terms of the bioavailability of isoflavones. (Korean J Nutrition 36(1): 32-39, 2003)

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.821-825
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• 2018

A copy number amplification system for yeast artificial chromosomes (YACs) was combined with simultaneous overexpression of genes integrated into a YAC. The chromosome VII (1,105 kb) was successfully split to 887 kb, 44 kb containing the element for copy number amplification, and a 184-kb split-YAC. The 44-kb split-mini YAC was amplified a maximum of 9-fold, and the activity of the reporter enzymes integrated into the split-mini YAC increased about 5-7-fold. These results demonstrate that the mini-YAC containing a targeted chromosome region can be readily amplified, and the specific genes in the mini-YAC could be overexpressed by increasing the copy number.

• Journal of Dairy Science and Biotechnology
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• v.39 no.4
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• pp.166-171
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• 2021

Since 1903, the International Dairy Federation (IDF) has been providing information on policies, standards, and regulations of the dairy industries to reach a global consensus on how to help feed the world with safe and sustainable dairy products. The 2021 IDF Global Dairy Conference was held in Copenhagen, Denmark with the theme of 'A Changing Climate for Dairy' for three days from the 13^th to the 15^th of October. Over 350 worldwide participants came together were expected to come together with several hundred additional online participants. An interesting topic among those presented at the conference was artificial milk at the Processing & Technology session on October 14^th. Dr. Eisner presented "Milk by Fermentation", in which he presented the technique of culturing and manufacturing artificial milk, based on artificially producing the caseins and enzymes through precision fermentation, which is suitable for making artificial cheeses. During the conference, the IDF launched the latest edition of the publication on global dairy markets, titled the World Dairy Situation Report 2021. According to report, South Korea is ranked 3^rd in the world for cheese imports.

• KSBB Journal
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• v.30 no.1
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• pp.1-10
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• 2015

Nanomaterial-based artificial enzymes (Nanozymes) have attracted recent attention because of their unique advantageous characteristics such as excellent robustness and stability, low-cost production by facile scale-up, and longterm preservation capability that are critically required as an alternative to natural enzymes. These nanozymes exhibit natural enzyme-like activity, and they have been applied to diverse kinds of detection methods for disease-associated biomolecules such as DNAs, proteins, cells, and small molecules including glucose. To highlight the progress in the field of disease diagnostics using nanozyme, this review discusses many nanozyme-based detection methods categorized by the types of target biomolecules. Finally, we address the current challenges and perspectives for the widespread utilization of nanozyme-based disease diagnostics.

• Proceedings of the KSCN Conference
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• 2001.05a
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• pp.459.2-460
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• 2001

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.18 no.8
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• pp.78-89
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• 2000

Today's computers are built up from a minimal set of standard pattern recognition operations. Logic gates, such as NAND, are common examples. Biomolecular materials offer an alternative approach, both in terms of variety and context sensitivity. Enzymes, the basic switching elements in biological cells, are notable for their ability to discriminate specific molecules in a complex background and to do so in a manner that is sensitive to particular milieu features and indifferent to others, The enzyme, in effect, is a powerful context sensitivity pattern processor that in a rough way can be analogized to a neuron whose input-output behavior is controlled by enzymatic dynamics.