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Green finance and environmental, social, and governance: evidence from Chinese listed companies

Wu J, Liew CY

Environ Sci Pollut Res Int, 2023 Nov;30(51):110499-110514.
PMID: 37792189 DOI: 10.1007/s11356-023-30139-x

In recent years, academics have paid more attention to green finance, and public companies have reached a broad consensus on the concept of timely environmental, social, and governance (ESG) disclosure. Due to the close relationship between green finance and ESG, this presents an opportunity to determine whether green finance compels companies to actively disclose ESG. The sample for this study consists of China's non-financial A-share listed companies from 2010 to 2021, and the empirical findings demonstrate that green finance can positively influence the ESG performance of listed companies. Through an analysis of heterogeneity, this study reaches the following conclusions: state-owned enterprises, heavy pollution companies, and companies in low-carbon pilot cities perform better in terms of green finance's role in promoting ESG scoring. This study also introduces market concentration and social trust as the moderating variables, enriching the green finance research framework. Through the analysis of moderating variables, the 'black box' effect of green finance on ESG is disclosed, providing theoretical support for the government and companies to better comprehend the policy effect as well as a reference for reform and experimental promotion of green finance.
Vitamin E analysis by ultra-performance convergence chromatography and structural elucidation of novel α-tocodienol by high-resolution mass spectrometry

Gee PT, Liew CY, Thong MC, Gay MC

Food Chem, 2016 Apr 1;196:367-73.
PMID: 26593503 DOI: 10.1016/j.foodchem.2015.09.073

We have developed a method for analysing vitamin E using ultra-performance convergence chromatography with a chromatographic runtime of 5.5 min. A well-resolved chromatogram with excellent precision in retention time revealed seven vitamin E components in the palm oil derived tocotrienol-rich fraction. The major vitamin E components were α-tocopherol, α-tocotrienol, γ-tocotrienol and δ-tocotrienol whereas the minor vitamin E components were α-tocomonoenol, β-tocotrienol and an unreported trace component. The new component was positively identified by high-resolution mass spectrometry as 2-methyl-2(4',8',12'-trimethyltrideca-7',11'-dienyl)5,7,8-trimethylchroman-6-ol or α-tocodienol.
Lignin biodegradation and ligninolytic enzyme studies during biopulping of Acacia mangium wood chips by tropical white rot fungi

Liew CY, Husaini A, Hussain H, Muid S, Liew KC, Roslan HA

World J Microbiol Biotechnol, 2011 Jun;27(6):1457-68.
PMID: 25187145 DOI: 10.1007/s11274-010-0598-x

White rot fungi are good lignin degraders and have the potential to be used in industry. In the present work, Phellinus sp., Daedalea sp., Trametes versicolor and Pycnoporus coccineus were selected due to their relatively high ligninolytic enzyme activity, and grown on Acacia mangium wood chips under solid state fermentation. Results obtained showed that manganese peroxidase produced is far more compared to lignin peroxidase, suggesting that MnP might be the predominating enzymes causing lignin degradation in Acacia mangium wood chips. Cellulase enzyme assays showed that no significant cellulase activity was detected in the enzyme preparation of T. versicolor and Phellinus sp. This low cellulolytic activity further suggests that these two white rot strains are of more interest in lignin degradation. The results on lignin losses showed 20-30% of lignin breakdown at 60 days of biodegradation. The highest lignin loss was found in Acacia mangium biotreated with T. versicolor after 60 days and recorded 26.9%, corresponding to the percentage of their wood weight loss recorded followed by P. coccineus. In general, lignin degradation was only significant from 20 days onwards. The overall percentage of lignin weight loss was within the range of 1.02-26.90% over the biodegradation periods. Microscopic observations conducted using scanning electron microscope showed that T. versicolor, P. coccineus, Daedalea sp. and Phellinus sp. had caused lignin degradation in Acacia mangium wood chips.
A methodology framework for bipartite network modeling

Liew CY, Labadin J, Kok WC, Eze MO

Appl Netw Sci, 2023;8(1):6.
PMID: 36684825 DOI: 10.1007/s41109-023-00533-y

The graph-theoretic based studies employing bipartite network approach mostly focus on surveying the statistical properties of the structure and behavior of the network systems under the domain of complex network analysis. They aim to provide the big-picture-view insights of a networked system by looking into the dynamic interaction and relationship among the vertices. Nonetheless, incorporating the features of individual vertex and capturing the dynamic interaction of the heterogeneous local rules governing each of them in the studies is lacking. The methodology in achieving this could hardly be found. Consequently, this study intends to propose a methodology framework that considers the influence of heterogeneous features of each node to the overall network behavior in modeling real-world bipartite network system. The proposed framework consists of three main stages with principal processes detailed in each stage, and three libraries of techniques to guide the modeling activities. It is iterative and process-oriented in nature and allows future network expansion. Two case studies from the domain of communicable disease in epidemiology and habitat suitability in ecology employing this framework are also presented. The results obtained suggest that the methodology could serve as a generic framework in advancing the current state of the art of bipartite network approach.
Effects of 3-(2-Hydroxyphenyl)-1-(5-methyl-furan-2-y-l) propenone (HMP) upon signalling pathways of lipopolysaccharide-induced iNOS synthesis in RAW 264.7 cells

Liew CY, Lam KW, Kim MK, Harith HH, Tham CL, Cheah YK, et al.

Int Immunopharmacol, 2011 Jan;11(1):85-95.
PMID: 21035434 DOI: 10.1016/j.intimp.2010.10.011

We previously showed that 3-(2-hydroxyphenyl)-1-(5-methyl-furan-2-y-l)propenone (HMP), suppressed the synthesis of various proinflammatory mediators. In this study, HMP showed a dose-dependent inhibition of NO synthesis in the RAW 264.7 murine macrophage line. The inhibition of NO synthesis was related to inhibition of p38 phosphorylation and kinase activity that led to significant inhibition of phosphorylation of ATF-2. This effect in turn caused inhibition of AP-1-DNA binding which partially explains the inhibitory effect upon the synthesis of iNOS. HMP had no effect upon phosphorylation of JNK, ERK1/2 and STAT-1. Kinase activity of JNK and ERK1/2 was also not affected by HMP as determined by levels of phosphorylated c-jun and phosphorylated elk-1. Furthermore HMP failed to block phosphorylation of IκBα, and subsequent nuclear translocation and DNA-binding activity of p65 NF-κB in IFN-γ/LPS-induced RAW 264.7 cells. Molecular docking experiments confirmed that HMP fits well in the highly conserved hydrophobic pocket of p38 MAP kinase. We conclude that the synthetic HMP is a chalcone analogue that selectively inhibits the p38/ATF-2 and AP-1 signaling pathways in the NO synthesis by the macrophage RAW 264.7.
Flavonoid combinations cause synergistic inhibition of proinflammatory mediator secretion from lipopolysaccharide-induced RAW 264.7 cells

Harasstani OA, Moin S, Tham CL, Liew CY, Ismail N, Rajajendram R, et al.

Inflamm Res, 2010 Sep;59(9):711-21.
PMID: 20221843 DOI: 10.1007/s00011-010-0182-8

OBJECTIVES: We evaluated several flavonoid combinations for synergy in the inhibition of proinflammatory mediator synthesis in the RAW 264.7 cellular model of inflammation.
METHODS: The inhibitory effect of chrysin, kaempferol, morin, silibinin, quercetin, diosmin and hesperidin upon nitric oxide (NO), prostaglandin E(2) (PGE(2)) and tumour necrosis factor-alpha (TNF-alpha) secretion from the LPS-induced RAW 264.7 monocytic macrophage was assessed and IC(50) values obtained. Flavonoids that showed reasonable inhibitory effects in at least two out of the three assays were combined in a series of fixed IC(50) ratios and reassessed for inhibition of NO, PGE(2) and TNF-alpha. Dose-response curves were generated and interactions were analysed using isobolographic analysis.
RESULTS: The experiments showed that only chrysin, kaempferol, morin, and silibinin were potent enough to produce dose-response effects upon at least two out of the three mediators assayed. Combinations of these four flavonoids showed that several combinations afforded highly significant synergistic effects.
CONCLUSIONS: Some flavonoids are synergistic in their anti-inflammatory effects when combined. In particular chrysin and kaempferol significantly synergised in their inhibitory effect upon NO, PGE(2) and TNF-alpha secretion. These findings open further avenues of research into combinatorial therapeutics of inflammatory-related diseases and the pharmacology of flavonoid synergy.
A synthetic curcuminoid derivative inhibits nitric oxide and proinflammatory cytokine synthesis

Tham CL, Liew CY, Lam KW, Mohamad AS, Kim MK, Cheah YK, et al.

Eur J Pharmacol, 2010 Feb 25;628(1-3):247-54.
PMID: 19958764 DOI: 10.1016/j.ejphar.2009.11.053

Curcumin is a highly pleiotropic molecule with significant regulatory effects upon inflammation and inflammatory related diseases. However curcumin has one major important limitation in which it has poor bioavailability. Design of synthetic structural derivatives of curcumin is but one approach that has been used to overcome its poor bioavailability while retaining, or further enhancing, its drug-like effects. We have synthesized a series of curcumin analogues and describe the effects of 2,6-bis-4-(hydroxyl-3-methoxy-benzylidine)-cyclohexanone or BHMC upon nitric oxide and cytokine synthesis in cellular models of inflammation. BHMC showed a significant dose-response inhibitory action upon the synthesis of NO and we have shown that this effect was due to suppression of both iNOS gene and enzyme expression without any effects upon scavenging of nitrite. We also demonstrated that BHMC has a very minimal effect upon iNOS activity with no effect at all upon the secretion of PGE(2) but has a strong inhibitory effect upon MCP-1 and IL-10 secretion and gene expression. Secretion and gene expression of TNF-alpha and IL-6 were moderately inhibited whereas IL-8 and IL-1beta were not altered. We conclude that BHMC selectively inhibits the synthesis of several inflammatory mediators. BHMC should be considered a promising drug lead for preclinical and further pharmacological studies.
A synthetic hydroxypropenone inhibits nitric oxide, prostaglandin E2, and proinflammatory cytokine synthesis

Liew CY, Tham CL, Lam KW, Mohamad AS, Kim MK, Cheah YK, et al.

Immunopharmacol Immunotoxicol, 2010 Sep;32(3):495-506.
PMID: 20109039 DOI: 10.3109/08923970903575708

HMP [3-(2-hydroxyphenyl)-1-(5-methyl-furan-2-y-l) propenone] was evaluated for its ability to inhibit the synthesis of major proinflammatory mediators and cytokines in interferon-gamma (IFN-gamma)- and lipopolysaccharide (LPS)-induced RAW 264.7 cells and phorbol myristate acetate (PMA)-differentiated/LPS-induced U937 cells. HMP suppressed the production of nitric oxide (NO) with significant inhibitory effects at doses as low as 0.78 microM (P < 0.05). Prostaglandin E2 (PGE2) secretion was also inhibited at doses of 12.5 microM and above (P < 0.01). The secretion of both TNF-alpha and IL-6 were only inhibited at the highest dose used (25 microM; P < 0.001). IL-1beta secretion was also inhibited from 12.5 microM onwards (P < 0.01). This inhibition was demonstrated to be caused by down-regulation of inducible enzymes, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), without direct effect upon iNOS or COX-2 enzyme activity. HMP only inhibited iNOS (P < 0.001) and IL-1beta (P < 0.05) gene expression at the highest tested concentration. HMP did not affect the secretion of chemokines IL-8 and monocyte chemotactic protein-1 (MCP-1) and the anti-inflammatory cytokine IL-10. The most striking effect of HMP was its NO inhibitory activity and therefore we conclude that HMP is a selective inhibitor of iNOS.