• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.69-79
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• 2012

In an ongoing survey of the bioactive potential of microorganisms from Ladakh, India, the culture medium of a bacterial strain of a new Pseudomonas sp., strain ICTB-745, isolated from an alkaline soil sample collected from Leh, Ladakh, India, was found to contain metabolites that exhibited broad-spectrum antimicrobial and biosurfactant activities. Bioactivity-guided purification resulted in the isolation of four bioactive compounds. Their chemical structures were elucidated by $^1H$ and $^{13}C$ NMR, 2D-NMR (HMBC, HSQC, $^1H$,$^1H$-COSY, and DEPT-135), FT-IR, and mass spectroscopic methods, and were identified as 1-hydroxyphenazine, phenazine-1-carboxylic acid (PCA), rhamnolipid-1 (RL-1), and rhamnolipid-2 (RL-2). These metabolites exhibited various biological activities like antimicrobial and efficient cytotoxic potencies against different human tumor cell lines such as HeLa, HepG2, A549, and MDA MB 231. RL-1 and RL-2 exhibited a dose-dependent antifeedant activity against Spodoptera litura, producing about 82.06% and 73.66% antifeedant activity, whereas PCA showed a moderate antifeedant activity (63.67%) at 60 ${\mu}g/cm^2$ area of castor leaf. Furthermore, PCA, RL-1, and RL-2 exhibited about 65%, 52%, and 47% mortality, respectively, against Rhyzopertha dominica at 20 ${\mu}g/ml$. This is the first report of rhamnolipids as antifeedant metabolites against Spodoptera litura and as insecticidal metabolites against Rhyzopertha dominica. The metabolites from Pseudomonas sp. strain ICTB-745 have interesting potential for use as a biopesticide in pest control programs.

• Journal of Microbiology
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• 제43권3호
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• pp.301-307
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• 2005

The feasibility of laccase production by immobilization of Pleurotus ostreatus 1804 on polyurethane foam (PUF) cubes with respect to media composition was studied in both batch and reactor systems. Enhanced laccase yield was evidenced due to immobilization. A relatively high maximum laccase activity of 312.6 U was observed with immobilized mycelia in shake flasks compared to the maximum laccase activity of free mycelia (272.2 U). It is evident from this study that the culture conditions studied, i.e. biomass level, pH, substrate concentration, yeast extract concentration, $Cu^{2+}$ concentration, and alcohol nature, showed significant influence on the laccase yield. Gel electrophoretic analysis showed the molecular weight of the laccase produced by immobilized P. ostreatus to be 66 kDa. The laccase yield was significantly higher and more rapid in the packed bed reactor than in the shake flask experiments. A maximum laccase yield of 392.9 U was observed within 144 h of the fermentation period with complete glucose depletion.

• 한국동물생명공학회지
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• 제38권2호
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• pp.54-61
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• 2023

Background: Germ cells undergo towards male or female pathways to produce spermatozoa or oocyte respectively which is essential for sexual reproduction. Mesenchymal stem cells (MSCs) have the potential of trans-differentiation to the multiple cell lineages. Methods: Herein, rat MSCs were isolated from bone marrow and characterized by their morphological features, expression of MSC surface markers, and in vitro differentiation capability. Results: Thereafter, we induced these cells only by retinoic acid supplementation in MSC medium and, could able to show that bone marrow derived MSCs are capable to trans-differentiate into male germ cell-like cells in vitro. We characterized these cells by morphological changes, the expressions of germ cell specific markers by immunophenotyping and molecular biology tools. Further, we quantified these differentiated cells. Conclusions: This study suggests that only Retinoic acid in culture medium could induce bone marrow MSCs to differentiate germ cell-like cells in vitro. This basic method of germ cell generation might be helpful in the prospective applications of this technology.

• 천문학논총
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• 제30권2호
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• pp.705-707
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• 2015

Astronomical observation is the beginning of scientific attitudes in the history of mankind. According to Indian tradition, there existed 18 early astronomical texts (siddhantas) composed by Surya, Pitamaha and many others. Varahamihira compiled five astronomical texts in a book named panchasiddhantika, which is now the link between early and later siddhantas. Indian scholars had no practice of writing their own names in their works, so, it is very difficult to identify them. Aryabhata is the first name noticed, in the book Aryabhatiya. After this point most astronomers and astro-writers wrote their names in their works. In this paper I have tried to analyze the works of astronomers like Aryabhata, Varahamihira, Brahmagupta, Bhaskara I, Vateswara, Sripati and Bhaskaracharya in a modern context and to obtain an account of Indian astronomical knowledge. Aryabhata is the first Indian astronomer who stated that the rising and setting of the Sun, the Moon and other heavenly bodies was due to the relative motion of the Earth caused by the rotation of the Earth about its own axis. He also estabished the 'yuga' theory (one Mahayuga = 432000 years). Varahamihira compiled panchasiddhantika and wrote Brihatsamhita. Brahmagupta is the most distinguished astronomer known to us. His two major works are i) Brahmasphutasiddhanta and ii) Khandkhadaka. Bhaskara I was the follower of Aryabhata. His three known works are Mahabhaskariya, Laghubhaskariya and Aryabhatiyabhasya. Vateswara follows Aryapaksha and Saurapaksha. His master work is Vateswarasiddhanta. Sripati, in his siddhantasekhara, gives the rules for determining the Moon's second inequality. Bhaskara II wrote the most comprehensive astronomical work in Indian astronomy. The result of these works is the account of the Indian astronomical heritage. These works are written in the Sanskrit language. A very few of these manuscripts have been translated in English but many are yet to be done. So, it is necessary to translate these astronomical texts into English with proper commentary for modern scholars. This paper will be helpful in this work.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 somma/kms meeting
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• pp.344-344
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• 2003

• 천문학회보
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• 제25권2호
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• pp.98-98
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• 2000

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.1931-1932
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• 2014

• 대한수학회보
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• 제51권6호
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• pp.1605-1614
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• 2014

In continuation to the investigation initiated by Ferraz, Goodaire and Milies in [4], we provide an explicit description for the Wedderburn decomposition of finite semisimple group algebras of the class of finite groups G, such that $$G/Z(G){\simeq_-}C_2{\times}C_2$$, where Z(G) denotes the center of G.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2016년도 임시총회 및 하계학술연구발표회
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• pp.183-185
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• 2016

• Toxicological Research
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• 제34권4호
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• pp.311-324
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• 2018

Arsenic is one of the most toxic environmental toxicants. More than 150 million people worldwide are exposed to arsenic through ground water contamination. It is an exclusive human carcinogen. Although the hallmarks of arsenic toxicity are skin lesions and skin cancers, arsenic can also induce cancers in the lung, liver, kidney, urinary bladder, and other internal organs. Arsenic is a non-mutagenic compound but can induce significant cytogenetic damage as measured by chromosomal aberrations, sister chromatid exchanges, and micronuclei formation in human systems. These genotoxic end points are extensively used to predict genotoxic potentials of different environmental chemicals, drugs, pesticides, and insecticides. These cytogenetic end points are also used for evaluating cancer risk. Here, by critically reviewing and analyzing the existing literature, we conclude that inorganic arsenic is a genotoxic carcinogen.