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153. Chromatographic and Spectral Fingerprinting of Polyalthia longifolia, a Source of Phytochemicals

Author

Sreenivasan Sasidharan, Subramanion L. Jothy, and Chen Yeng

Subjects
Environmental Engineering, Characterization, Materials Science, aerial parts, Saponin, Bioengineering, Phytochemical, Mass spectrometry, High-performance liquid chromatography, quality-control, chemistry.chemical_compound, indian medicinal-plants, Anthraquinones, Polyalthia longifolia, P. longifolia, constituents, extract, Medicinal plants, Waste Management and Disposal, mass spectrometry, chemistry.chemical_classification, Chromatography, biology, Chemistry, Glycoside, biology.organism_classification, Fingerprinting techniques, products, Heavy metal, canary-islands, authentication, var. pendula
Abstract

Medicinal plants, such as Polyalthia longifolia (Indian mast tree), are important therapeutic sources for curing human diseases. In this work P. longifolia leaf extract was characterized by chromatographic and spectral fingerprinting techniques, phytochemical and heavy metal analyses, and microscopy. Light microscopy of a transverse section of the leaf of P. longifolia revealed the presence of various plant cells. Phytochemical screening results revealed the presence of alkaloids, triterpenoids, tannins, saponin, anthraquinones, and glycosides in the extract. The concentrations of heavy metals determined in the extract were well below the permissible limit. Nine peaks observed in the HPLC spectra showed the presence of various compounds in the extract. The GCMS method used for quantification of (3 beta,4 alpha,5 alpha,9 beta)-4,14-dimethyl-9,19-cycloergost-24(28)-en-3-yl acetate (i.e., cycloeucalenol acetate) in the extract was rapid, accurate, precise, linear (R-2 = 0.8752), and robust. The HPTLC analysis showed ten specific peaks for the methanolic extract of P. longifolia leaf. Twelve major peaks in the range of 4,000 to 500 cm(-1) were observed in the FTIR spectra, which represented various specific functional groups in the extract.

Published
2013

154. Evaluation of the Genotoxic Potential against H2O2-Radical-Mediated DNA Damage and Acute Oral Toxicity of Standardized Extract of Polyalthia longifolia Leaf

Author

Jothy, Subramanion L., Chen, Yeng, Kanwar, Jagat R., and Sasidharan, Sreenivasan

Subjects
Article Subject, food and beverages, lcsh:Other systems of medicine, lcsh:RZ201-999, Research Article
Abstract

Medicinal plants have been used in medicoculturally diverse countries around the world, where it is a part of a time-honoured tradition that is respected even today. Polyalthia longifolia leaf extract has been previously reported as an efficient antioxidant in vitro. Hence, the genotoxic effects of P. longifolia leaf were investigated by using plasmid relation, comet, and Allium cepa assay. In the presence of ∙OH radicals, the DNA in supercoil was start nicked into open circular form, which is the product of the single-stranded cleavage of supercoil DNA and quantified as fragmented separate bands on agarose gel in plasmid relation assay. In the plasmid relation and comet assay, the P. longifolia leaf extract exhibited strong inhibitory effects against H2O2-mediated DNA damage. A dose-dependent increase of chromosome aberrations was also observed in the Allium cepa assay. The abnormalities scored were stickiness, c-mitosis, bridges, and vagrant chromosomes. Micronucleated cells were also observed at the interphase. The results of Allium cepa assay confirmed that the methanol extracts of P. longifolia exerted no significant genotoxic or mitodepressive effects at 100 μg/mL. Thus, this study demonstrated that P. longifolia leaf extract has a beneficial effect against oxidative DNA damage. This experiment is the first report for the protective effect of P. longifolia on DNA damage-induced by hydroxyl radicals. Additionally in acute oral toxicity study, female rats were treated at 5000 mg/kg body weight of P. longifolia leaf extract and observed for signs of toxicity for 14 days. P. longifolia leaf extract did not produce any treatment-related toxic effects in rats.

Published
2013

156. Anticancer Activity and Molecular Mechanism of Polyphenol Rich Calophyllum inophyllum Fruit Extract in MCF-7 Breast Cancer Cells.

Author

Shanmugapriya, Chen, Yeng, Kanwar, Jagat R., and Sasidharan, Sreenivasan

Subjects
*PROTEIN metabolism, *ENZYME metabolism, *REACTIVE oxygen species, *ANTINEOPLASTIC agents, *APOPTOSIS, *BIOLOGICAL assay, *BIOLOGICAL models, *BIOLOGICAL transport, *CELL cycle, *DOSE-effect relationship in pharmacology, *FLOW cytometry, *FRUIT, *MEDICINAL plants, *MITOCHONDRIA, *PLANT extracts, *IN vitro studies, *PHARMACODYNAMICS, BREAST tumor prevention
Abstract

This study was conducted to investigate the anticancer effects and mechanism of Calophyllum inophyllum fruit extract against MCF-7 cells. C. inophyllum fruit extract was found to have markedly cytotoxic effect against MCF-7 cells in a dose-dependent manner with the IC50 for 24 h of 23.59 µg/mL. Flow cytometry analysis revealed that C. inophyllum fruit extract mediated cell cycle at G0/G1 and G2/M phases, and MCF-7 cells entered the early phase of apoptosis. The expression of anti-apoptotic proteins Bcl-2 was decreased whereas the expression of the pro-apoptotic protein Bax, cytochrome C and p53 were increased after treatment. C. inophyllum fruit extract led to apoptosis in MCF-7 cells via the mitochondrial pathway in a dose dependent manner. This is evidenced by the elevation of intracellular ROS, the loss of mitochondria membrane potential (Δψm), and activation of caspase-3. Meanwhile, dose-dependent genomic DNA fragmentation was observed after C. inophyllum fruits extract treatment by comet assay. This study shows that C. inophyllum fruits extract-induced apoptosis is primarily p53 dependent and mediated through the activation of caspase-3. C. inophyllum fruit extract could be an excellent source of chemopreventive agent in the treatment of breast cancer and has potential to be explored as green anticancer agent. [ABSTRACT FROM AUTHOR]

Published
2017
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157. Chemical composition and antioxidant activity of the crude methanolic extracts of Mentha spicata

Author

J Rameshwar Naidu, R B Ismail, Chen Yeng, S Sasidharan, and Kumar P

Subjects
lcsh:Agriculture, lcsh:S, antioxidant activity, lcsh:Q, Alocacia Mentha spicata, lcsh:Science, GC-TOFMS, chemical profiling
Abstract

The chemical constituents and antioxidant activity of the crude extracts of Mentha spicata were investigated. Phytochemical analysis indicated the presence of sugar, flavonoids and alkaloids in the crude extracts of Mentha spicata. GC-TOFMS (Gas Chromatography Time-of-Flight Mass Spectrometry) analysis indicated the presence of fatty acid methyl esters (hexa decane, hepta decane, octa decane) terpenoids, terpenoid alcohol, caryophyllene and glycosides. Total phenolic components of the crude extracts was found to be 27.26±0.62 mg/g gallic acid equivalent which was determined by Folin-Ciocalteu method. The DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity was found to increase with increasing concentrations and was found to be 54.84±0.57% with an IC50 value of 25.2µg/ml. The reported antioxidant activity may be due to the presence of flavonoids and fatty acid methyl esters which has the scavenging potential by reducing the free radicals.

Published
2012

165. Application of real-time polymerase chain reaction in detection of Entamoeba histolytica in pus aspirates of liver abscess patients

Author

Lim Boon Huat, Alfonso Olivos-García, Nurulhasanah Othman, Zeehaida Mohamed, Jaco J. Verweij, Chen Yeng, and Rahmah Noordin

Subjects
Microbiological culture, Time Factors, Antibodies, Protozoan, Applied Microbiology and Biotechnology, Microbiology, Polymerase Chain Reaction, Sensitivity and Specificity, law.invention, Diagnosis, Differential, Entamoeba histolytica, fluids and secretions, law, Limit of Detection, parasitic diseases, medicine, Humans, Amoebiasis, Polymerase chain reaction, Pyogenic liver abscess, Amoebic liver abscess, Suppuration, biology, Entamoebiasis, Hemagglutination Tests, DNA, Protozoan, medicine.disease, biology.organism_classification, bacterial infections and mycoses, Virology, Bacterial Typing Techniques, Real-time polymerase chain reaction, Liver Abscess, Pyogenic, Liver Abscess, Amebic, diagnosis amebiasis pcr antigen samples assay ala, Animal Science and Zoology, Food Science, Liver abscess
Abstract

Entamoeba histolytica is the second major cause of liver abscess disease in humans, particularly in developing countries. Recently, DNA molecular-based methods have been employed to enhance the detection of E. histolytica in either pus or stool specimens. In this study, the results of real-time polymerase chain reaction (PCR) to detect E. histolytica DNA in pus from liver abscess cases were compared with those of indirect hemagglutination assay on the corresponding serum samples. Bacterial cultures were also performed on the pus samples for the diagnosis of pyogenic liver abscess. The real-time PCR detected E. histolytica DNA in 23 of 30 (76.7) pus samples, when compared with 14 of 30 (46.7) serum samples in which anti-Entamoeba antibodies were detected by indirect hemagglutination assay and 4 of 30 (13.3) pus samples that showed bacterial infection by culture. The use of real-time PCR is a promising detection method for diagnosis and epidemiology assessment of amoebic liver abscess. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down.

Published
2010

168. A multi-objective model for solar industry closed-loop supply chain by using particle swarm optimization

Author

International FAIM Conference 24th : 2014 : San Antonio, Texas; University of Texas at San Antonio. Center for Advanced Manufacturing and Lean Systems, Chen, YiWen; Wang, Li-Chih; Chen, Tzu-Li; Wang, Allen; Cheng, Chen-Yeng, International FAIM Conference 24th : 2014 : San Antonio, Texas; University of Texas at San Antonio. Center for Advanced Manufacturing and Lean Systems, and Chen, YiWen; Wang, Li-Chih; Chen, Tzu-Li; Wang, Allen; Cheng, Chen-Yeng

Abstract

Paper presented at the Proceedings of the 24th International Conference on Flexible Automation & Intelligent Manufacturing, held May 20-23, 2014 in San Antonio, Texas, and organized by the Center for Advanced Manufacturing and Lean Systems, University of Texas at San Antonio; Includes bibliographical references; Solar energy industry is an exceptional industry which desperately relies on government support and subsidy. The demand is decreasing since the government support reduction, moreover, the dramatically increase China solar manufacturers have great impact on solar product price in recent years. Because the insufficient supply of silicon materials carries the issue of solar cell recycle, the solar manufacturer must design a sustainable closed-loop supply chain (CLSC) to recycle and reuse the retired solar cells to achieve 3E (Effective, Efficient, Environmental; 3E) objectives. This paper studies an integrated CLSC network design problem with sustainable concerns in the solar energy industry. We are interested in the logistics flows, capacity expansion and technology investments of existing and potential facilities in the multi-stage CLSC. Therefore, a deterministic multi-objective mixed integer programming model capturing the tradeoffs between the total cost and the carbon dioxide (CO2) emission is developed to tackle the multi-stage CLSC design problem from both economic and environmental perspectives. Due to the multi-objective nature and computational complexity, a multi-objective particle swarm optimization (MOPSO) with novel flow assignment algorithms is designed to search non-dominated /Pareto CLSC design solutions. Finally, a case study of crystalline solar energy industry is illustrated to verify the proposed multi-objective CLSC design model and demonstrate the efficiency of the developed MOPSO algorithm in terms of computational time and solution quality

Published
2014

175. Abstract 1309: Identification of aurora kinase a as an unfavorable prognostic factor and potential treatment target for metastatic gastrointestinal stromal tumors

Author

Yeh, Chun-Nan, primary, Yen, Chueh-Chuan, additional, Chen, Yeng-Yang, additional, Cheng, Chi-Tung, additional, Huang, Shih-Chiang, additional, Chang, Ting-Wei, additional, Yao, Fang-Yi, additional, Lin, Yung-Chan, additional, Wen, Yao-Shan, additional, Chiang, Kun-Chun, additional, Chen, Jen-Shi, additional, Yeh, Ta-Sen, additional, Tzeng, Cheng-Hwai, additional, Chao, Ta-Chung, additional, and Fletcher, Jonathan A., additional

Published
2014
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180. Antitumor activity of the combination of an HSP90 inhibitor and a PI3K/mTOR dual inhibitor against cholangiocarcinoma

Author

Chen, Ming-Huang, primary, Chiang, Kun-Chun, additional, Cheng, Chi-Tung, additional, Huang, Shih-Chiang, additional, Chen, Yeng-Yang, additional, Chen, Tsung-Wen, additional, Yeh, Ta-Sen, additional, Jan, Yi-Yin, additional, Wang, Hsi-Ming, additional, Weng, Jiang-Jie, additional, Chang, Peter Mu-Hsin, additional, Liu, Chun-Yu, additional, Li, Chung-Pin, additional, Chao, Yee, additional, Chen, Ming-Han, additional, Huang, Chi-Ying F., additional, and Yeh, Chun-Nan, additional

Published
2014
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184. Genoprotection and Cytotoxicity of Cassia surattensisSeed Extract on Vero Cell Evaluated by Comet and Cytotoxicity Assays

Author

Uthaya Kumar, U. Seeta, Jothy, Subramanion, Kavitha, Nowroji, Chen, Yeng, Kanwar, Jagat, and Sasidharan, Sreenivasan

Abstract

Cassia(C.) surattensisBurm. f. (Leguminosae) is a flowering plant that has been traditionally used in many countries for food and medicinal purposes. The present study was conducted to determine in vitro cytotoxicity and anti-genotoxic activity of the seed extract of C. surattensis. The cytotoxic and anti-genotoxic activities were evaluated against Vero cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and comet assays. In vitro cytotoxicity evaluation demonstrated that seed extract of C. surattensis was non-cytotoxic against the Vero cells. The 50 % cytotoxic concentration (CC50) value from MTT cytotoxicity assay was 332.87 µg/ml. The seed extract of C. surattensisexhibited strong inhibitory effects against H2O2-mediated DNA damage in Vero cells as observed in Comet assay. The presence of antioxidant activity in the seed extract was associated with the antigenotoxic property of C. surattensis. In summary, the present study demonstrated an efficient antigenotoxic property of C. surattensis, which is significant for future investigation for human applications.

Published
2018
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188. The antimicrobial efficacy of elaeis guineensis : characterization, in Vitro and in Vivo studies

Author

Vijayarathna, Soundararajan, Zakaria, Zuraini, Chen, Yeng, Latha, Lachimanan Yoga, Kanwar, Jagat R., Sasidharan, Sreenivasan, Vijayarathna, Soundararajan, Zakaria, Zuraini, Chen, Yeng, Latha, Lachimanan Yoga, Kanwar, Jagat R., and Sasidharan, Sreenivasan

Abstract

The urgent need to treat multi-drug resistant pathogenic microorganisms in chronically infected patients has given rise to the development of new antimicrobials from natural resources. We have tested Elaeis guineensis Jacq (Arecaceae) methanol extract against a variety of bacterial, fungal and yeast strains associated with infections. Our studies have demonstrated that E. guineensis exhibits excellent antimicrobial activity in vitro and in vivo against the bacterial and fungal strains tested. A marked inhibitory effect of the E. guineensis extracts was observed against C. albicans whereby E. guineensis extract at =, 1, or 2 times the MIC significantly inhibited C. albicans growth with a noticeable drop in optical density (OD) of the bacterial culture. This finding confirmed the anticandidal activity of the extract on C. albicans. Imaging using scanning (SEM) and transmission (TEM) electron microscopy was done to determine the major alterations in the microstructure of the extract-treated C. albicans. The main abnormalities noted via SEM and TEM studies were the alteration in morphology of the yeast cells. In vivo antimicrobial activity was studied in mice that had been inoculated with C. albicans and exhibited good anticandidal activity. The authors conclude that the extract may be used as a candidate for the development of anticandidal agent.

Published
2012

189. Genotoxicity of Euphorbia hirta: an Allium cepa assay

Author

Kwan, Yuet Ping, Ibrahim, Darah, Yusuf, Umi Kalsom, Chen, Yeng, Sreenivasan, Sasidharan, Kwan, Yuet Ping, Ibrahim, Darah, Yusuf, Umi Kalsom, Chen, Yeng, and Sreenivasan, Sasidharan

Abstract

The potential genotoxic effects of methanolic extracts of Euphorbia hirta which is commonly used in traditional medicine to treat a variety of diseased conditions including asthma, coughs, diarrhea and dysentery was investigated using Allium cepa assay. The extracts of 125, 250, 500 and 1,000 µg/mL were tested on root meristems of A. cepa. Ethylmethanesulfonate was used as positive control and distilled water was used as negative control. The result showed that mitotic index decreased as the concentrations of E. hirta extract increased. A dose-dependent increase of chromosome aberrations was also observed. Abnormalities scored were stickiness, c-mitosis, bridges and vagrant chromosomes. Micronucleated cells were also observed at interphase. Result of this study confirmed that the methanol extracts of E. hirta exerted significant genotoxic and mitodepressive effects at 1,000 µg/mL.

Published
2012

195. Potential of mean force between two nanometer-scale particles in a polymer solution

Author

Doxastakis, Manolis, Chen, Yeng-Long, de Pablo, Juan José, Doxastakis, Manolis, Chen, Yeng-Long, and de Pablo, Juan José

Abstract

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.

Published
2007

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