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219 results on '"Koh, Rhun Yian"'

9. BIOCHEMICAL AND TRANSCRIPTOMIC ANALYSIS OF DISEASE RESISTANCE AND EARLY-MATURITY RELATED GENES IN NMR-191 AND NMR-192 RICE MUTANT LINES

Author

Kiong Ling, Anna Pick, Yip, Tuck Mun, Hussein, Sobri Bin, Ahmad, Faiz Bin, Hase, Yoshihiro, Wong, Ying Pei, Koh, Rhun Yian, Kiong Ling, Anna Pick, Yip, Tuck Mun, Hussein, Sobri Bin, Ahmad, Faiz Bin, Hase, Yoshihiro, Wong, Ying Pei, and Koh, Rhun Yian

Abstract

Malaysia's rice industry has revealed that the rice production was unable to supply the food demand where nearly 30% was imported from other countries. This is due to the fact that rice cultivation in Malaysia faces concerns about rice blast disease, Magnaporthe oryzae attack, and having a long maturation period. As such, generation of new rice mutant lines that possess improved disease resistance and early maturity characteristics through mutation breeding techniques are of great importance. This study aimed to analyze the biochemical characteristics as well as to validate the presence of disease resistance and early maturity-related genes in rice mutant lines. After the rice seeds of the parent line Pongsu Seribu 2 (PS2) and mutant lines (NMR191 and NMR192) were grown for 14 days, the plant samples underwent biochemical tests including total soluble protein content, specific activity of peroxidase, chlorophyll content and proline content. The RNA extraction and sequencing were also conducted for the purpose of transcriptomic profiling analysis to determine the presence of disease resistance and early maturity genes in the samples. The biochemical analyses showed a significant increase in the total soluble protein content, chlorophyll content, and proline content in the mutant line NMR191 and NMR192 compared to the parent line, while the specific activity of peroxidase in the mutant lines was significantly lower compared to the parent line. The transcriptomic profiling analysis revealed that Os07g0129300, Os12g0270300, and Os03g0235000 were the disease-resistance genes whereas Os03g0195300, Os01g0704100, Os11g0143200, Os06g0569900, and Os06g0568600 were the early maturity genes found in NMR191 and NMR192. This study validates that NMR191 and NMR192 could be better varieties than the parent line due to the presence of their early maturity and disease resistance traits.

Published
2024

12. Development and evaluation of liquid crystal systems of combination of 5-fluorouracil and curcumin for cervical cancer cell line

Author

Sheba R David, Syahira Abdul Refai, Koh Rhun Yian, Chun-Wai Mai, Sanjoy Kumar Das, and Rajan Rajabalaya

Subjects
cervical cancer, curcumin, 5-fluorouracil, HeLa cell line, liquid crystal, Therapeutics. Pharmacology, RM1-950, Pharmacy and materia medica, RS1-441
Abstract

Context: Liquid crystalline gel, self-assembled vesicular systems covered with nonionic surfactants, are promising for use in drug delivery. Aims: To develop and evaluate the liquid crystal (LC) systems of a combination of 5-fluorouracil and curcumin for a cervical cancer cell line. Methods: The LC was formulated using water, surfactant, and glycerin. Optimization was carried out by using different surfactants. The formulations were chosen for various studies, such as pH determination, environmental scanning electron microscopy (eSEM), Fourier transform infrared spectroscopy (FTIR) and dissolution study. The synergism of the combination of 5-FU and curcumin on cervical cancer HeLa cell line was then analyzed using CompuSyn software. Results: The formulations with 60% surfactant, the average particle size was in the ranges from 15.68 – 26.35 nm whereas with 40% surfactant, were 11.27 – 21.35 nm. The percentage of dissolution of 5-FU at pH 7 (PBS) A2: 40.23 > B2: 47.39 > X2: 50.36 > Y2: 56.36 compared to at pH 4 (vaginal simulated fluid, VSF) were A2: 36.23 > B2: 43.64 > X2: 45.67 > Y2: 49.01. The percentage of dissolution of curcumin of different formulations were at pH 7 (PBS) A2: 44.85 > B2: 51.36 > X2: 58.61 > Y2: 64.38 compared to at pH 4 (VSF) were A2: 41.03 > B2: 49.37 > X2: 57.85 > Y2: 68.75. Conclusions: The combination of the drugs showed that there was a synergistic effect when it was being administered together. The combination of drugs in LC system had a sustained release as well as it was effective against cervical cancer HeLa cell line.

Published
2019

21. Development and Evaluation of Curcumin Liquid Crystal Systems for Cervical Cancer

Author

Sheba R David, Nurul Akmar Binti Anwar, Koh Rhun Yian, Chun-Wai Mai, Sanjoy Kumar Das, and Rajan Rajabalaya

Subjects
cervical cancer, liquid crystal, curcumin, hela cells, Pharmacy and materia medica, RS1-441
Abstract

Curcumin is a hydrophobic compound with good anti-proliferative, anti-oxidative, and anti-cancer properties but has poor bioavailability. Liquid crystals (LC) can accommodate both hydrophilic and hydrophobic drugs. The aim of this study was to formulate and evaluate a novel vaginal drug delivery system for cervical cancer using a curcumin LC system. The curcumin LC system was formulated using surfactant, glycerol, and water together with curcumin. Three types of surfactants were used to optimize the formulation, i.e., Tween 80, Cremphor EL, and Labrasol. The optimized formulations were subjected to physicochemical analysis, and their efficacy was evaluated in HeLa cells. The pH of the formulations was in the range of 3.91−4.39. Environmental scanning electron microscopy (ESEM) observations revealed spherical as well as hexagonal micelles. In vitro release of LC curcumin from vaginal simulated fluid (VSF, pH 4.5) showed a release from 20.47% to 87.25%. The IC50 of curcumin in HeLa cells was 22.5 μg/mL, while the IC25 and IC75 were 6.5 μg/mL and 35μg/mL, respectively. The cytotoxicity of the formulations was determined in comparison with liquid crystals without curcumin and pure curcumin by performing a t-test based on a significance level of p less than or equal to 0.05 (p ≤ 0.05). The curcumin LC system was able to release the required amount of drug and was effective against the cervical cancer cell line examined.

Published
2020
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35. Anti-neuroinflammatory responses in lipopolysaccharide-stimulated BV2 microglial cells upon treatment with methanol extract of Panax ginseng root

Author

Koay, Chien Yi, Ling, Anna Pick Kiong, Wong, Ying Pei, Koh, Rhun Yian, and Hussein, Sobri

Subjects
Inflammation, Lipopolysaccharides, Cyclooxygenase 2, Anti-Inflammatory Agents, NF-kappa B, Animals, Humans, Panax, Microglia, Nitric Oxide, Plant Roots, Drugs, Chinese Herbal
Abstract

To investigate the anti-neuroinflammatory properties of Panax ginseng (P. ginseng) root by measuring the levels of nitric oxide (NO), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) in lipopolysaccharide (LPS)-stimulated BV2 microglia cells.Maximal non-toxic dose (MNTD) of methanol extract of P. ginseng root culture on BV2 microglia cells was first determined via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, followed by treatment and LPS stimulation of cells, and the measurement of NO using Griess assay and TNF-α, IL-6, and IL-10 using ELISA assay.The MNTD of P. ginseng root extract was determined to be (587 ± 57) µg/mL. Following that, NO and IL-6 levels were found to be insignificantly reduced by 6.88% and 0.14% respectively in stimulated cells upon treatment with MNTD. Treatment with MNTD yielded similar insignificant result, with only a reduction of 3.58% and 0.08% in NO and IL-6 levels respectively. However, TNF-α and IL-10 levels were significantly downregulated by 15.64% and 34.96% respectively upon treatment with P. ginseng root extract at MNTD.Methanol extract of P. ginseng root culture did not show any significant anti-inflammatory effects on NO and IL-6 levels, but might potentially possess both anti-neuroinflammatory and pro-neuroinflammatory properties through the downregulation of TNF-α and IL-10 respectively.

Published
2021

44. Clinacanthus Nutans Hexane Extracts Induce Apoptosis Through a Caspase-Dependent Pathway in Human Cancer Cell Lines

Author

Ng, Pei Ying, Chye, Soi Moi, Ng, Chew Hee, Koh, Rhun Yian, Tiong, Yee Lian, Pui, Liew Phing, Tan, Yong Hui, Lim, Crystale Siew Ying, and Ng, Khuen Yen

Subjects
reactive oxygen species, caspase, Clinacanthus nutans, apoptosis, cancer, Research Article
Abstract

Background: Clinacanthus nutans (C.nutans) is a plant consumed as a cancer treatment in tropical Asia. Despite the availability of numerous anecdotal reports, evaluation of active anticancer effects has remained elusive. Therefore we here examined antiproliferative, reactive oxygen species (ROS)-inducing and apoptosis mechanisms of whole plant extracts in different cancer cell lines. Methods: Antiproliferative actions of five solvent extracts (hexane, chloroform, ethyl acetate, methanol and water) of C.nutans were tested on non-small cell lung cancer (A549), nasopharygeal cancer (CNE1) and liver cancer (HepG2) cells using MTT assay. The most potent anticancer extract was then assessed by flow cytometry to study cell cycle changes . Intracellular levels of ROS were quantified by DCFH-DA assay. Involvement of the caspase pathway in induction of apoptosis was assessed using caspase assay kits. GC-MS analysis was performed to identify phytoconstituents in the extracts. Results: Hexane and chloroform extracts were antiproliferative against all three cell lines, while the ethyl acetate extract, at 300 μg/mL, was antiproliferative in the CNE1 but not A549 and HepG2 cases. Methanol and water extracts did not inhibit cancer cell proliferation. The most potent anticancer hexane extract was selected for further testing. It induced apoptosis in all three cell lines as shown by an increase in the percentage of cell in sub-G1 phase. Dose-dependent increase in ROS levels in all three cell lines indicated apoptosis to be possibly modulated by oxidative stress. At high concentrations (100 μg/mL), hexane extracts upregulated caspases 8, 9 and 3/7 across all three cell lines. GC-MS analysis of the hexane extract revealed abundance of 31 compounds. Conclusion : Among the five extracts of C.nutans, that with hexane extract demonstrated the highest antiproliferative activity against all three cancer cell lines tested. Action appeared to be via ion of intracellular ROS, and induction of apoptosis via intrinsic and extrinsic caspase pathways.

Published
2017

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