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Surface area and porosity are the main factors that affect hydrogen storage at room temperature. However, there are several external factors such as pressure of gas, reaction time and the amount of sample used during the process that might affect the performance of the hybrid nanocomposites towards hydrogen storage. In this study, central composite design (CCD) for response surface methodology (RSM) was used in determining the optimum conditions namely mass of sample (A), pressure of hydrogen gas (B) and reaction time (C) towards the hydrogen storage at room temperature. Rice husk derived graphene-like material (GRHC) was added into zeolitic imidazolate frameworks-8 (ZIF-8) to form a hybrid nanocomposite of ZIF-8/GRHC (ZGK) via in-situ synthesis. Due to synergistic effect, the surface area of ZGK (1065.51 m2/g) shows a great enhancement as 0.04 g GRHC was introduced as compared to pristine ZIF-8 (687.32 m2/g). On the other hand, the thermal stability of ZGK improved significantly as it can withstand up to 1000 ºC as compared to pristine GRHC and ZIF-8 respectively. Due to superior physicochemical properties of ZGK, it was chosen to undergo optimization of hydrogen storage at room temperature. From the confirmatory test which was run for three times, the optimum hydrogen storage at room temperature in ZGK was 1.95 wt.% when 0.50 g of ZGK was used; 15 bar of hydrogen gas was applied and the reaction time was 60 min as per suggested from the CCD.Highlights: The addition of GRHC enhanced the surface area of ZGK up to 55 %. ZGK exhibited a smaller pore size, 0.81 nm which is desired to store hydrogen. Thermal stability of ZGK improved (~1000 ºC) as GRHC is introduced in the nanocomposites. The optimum condition for hydrogen storage was; 0.50 g of ZGK, 15 bar of hydrogen gas and 60 mins reaction time. The optimum hydrogen storage of ZGK at room temperature was around 1.95 wt. %. [ABSTRACT FROM AUTHOR]

In this study, two variations of magnetorheological elastomer (MRE) tensile specimens were fabricated, differing in their isotropic and anisotropic configurations. The isotropic MRE exhibited randomly dispersed carbonyl iron particle (CIP), whereas the anisotropic featured longitudinally aligned CIP particles along the gauge length of the tensile sample. The formation of the anisotropic MRE involved utilizing an electromagnetic curing chamber, which facilitated the alignment of CIP particles during the elastomer curing process. A mold was specifically designed to produce samples conforming to the dimensions outlined in ASTMD412-F. Subsequently, a Finite Element Method Magnetics (FEMM) analysis was conducted to examine the magnetic flux within the curing device for the anisotropic MRE. Uniaxial tensile tests were conducted on both MRE types, both in the absence and presence of a 30 mT magnetic field applied transversely to the direction of CIP alignment. Results indicated that without a magnetic field, the anisotropic sample exhibited a slightly higher tensile strength, lower elongation, and higher modulus at 100% strain. However, when a magnetic field was introduced, the isotropic sample demonstrated a more pronounced increase in tensile strength, showing an 18.4% improvement compared to the 5.6% increase observed in the anisotropic sample. Similar trends were observed in the reduction of elongation, with a 14% decrease for isotropic and a 7% decrease for anisotropic samples. Additionally, the data on modulus at a 100% strain revealed a 22.3% increase in stiffness for the isotropic sample, while the anisotropic sample showed a 10.6% increase. [ABSTRACT FROM AUTHOR]

Hanita Omar,1,2 Noraziah Nordin,3 Pouya Hassandarvish,4 Maryam Hajrezaie,5 Ainnul Hamidah Syahadah Azizan,1 Mehran Fadaeinasab,6 Nazia Abdul Majid,7 Mahmood Ameen Abdulla,5 Najihah Mohd Hashim,3 Hapipah Mohd Ali1 1Department of Chemistry, Faculty of Science, 2Centre for Foundation Studies in Science, 3Department of Pharmacy, 4Department of Microbiology, 5Department of Biomedical Sciences, Faculty of Medicine, 6Center for Natural Products and Drug Research (CENAR), 7Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia Abstract: Actinodaphne sesquipedalis Hook. F. Var. Glabra (Kochummen), also known as “Medang payung” by the Malay people, belongs to the Lauraceae family. In this study, methanol leaf extract of A. sesquipedalis was investigated for their acute toxicity and gastroprotective effects to reduce ulcers in rat stomachs induced by ethanol. The rats were assigned to one of five groups: normal group (group 1), ulcer group (group 2), control positive drug group (group 3) and two experimental groups treated with 150 mg/kg (group 4) and 300 mg/kg (group 5) of leaf extract. The rats were sacrificed an hour after pretreatment with extracts, and their stomach homogenates and tissues were collected for further evaluation. Macroscopic and histological analyses showed that gastric ulcers in rats pretreated with the extract were significantly reduced to an extent that it allowed leukocytes penetration of the gastric walls compared with the ulcer group. In addition, an ulcer inhibition rate of >70% was detected in rats treated with both doses of A. sesquipedalis extract, showing a notable protection of gastric layer. Severe destruction of gastric mucosa was prevented with a high production of mucus and pH gastric contents in both omeprazole-treated and extract-treated groups. Meanwhile, an increase in glycoprotein uptake was observed in pretreated rats through accumulation of magenta color in Periodic Acid Schiff staining assay. Analysis of gastric homogenate from pretreated rats showed a reduction of malondialdehyde and elevation of nitric oxide, glutathione, prostaglandin E2, superoxide dismutase and protein concentration levels in comparison with group 2. Suppression of apoptosis in gastric tissues by upregulation of Hsp70 protein and downregulation of Bax protein was also observed in rats pretreated with extract. Consistent results of a reduction of gastric ulcer and the protection of gastric wall were obtained for rats pretreated with A. sesquipedalis extract, which showed its prominent gastroprotective potential in rats’ stomach against ethanol-induced ulcer. Keywords: Actinodaphne sesquipedalis, methanol extracts, gastric ulcer, ethanol, mechanism

The present work aimed to identify the effects of knowledge, attitudes, and practices (KAP) of poultry handlers on the prevalence of Campylobacter along the poultry production chain in Peninsular Malaysia. A total of 1230 microbiological samples were collected from five companies in different Malaysian states. The sampling points involved the entire poultry supply chain from the farm to the retailer. The collected samples were subjected to bacteriological isolation and morphological identification for microbiological analyses. All Campylobacter-positive samples were further confirmed with molecular identification by using a polymerase chain reaction. Campylobacter prevalence in poultry farms, processing plants, and retailers were identified. For the KAP survey, 300 respondents answered a questionnaire evaluating their levels of KAP regarding food safety while handling live birds and subsequently poultry products after slaughtering. Overall, the mean KAP scores of the workers at farms, processing plants, and retail outlets were assessed. The survey data indicated that even though the overall KAP levels of the poultry workers were excellent, the bacterial prevalence of Campylobacter was still high. In conclusion, the KAP of poultry handlers had insignificant effects on the prevalence of Campylobacter along the poultry production chain in Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

Venoos Iman,1 Syam Mohan,2 Siddig Ibrahim Abdelwahab,2 Hamed Karimian,1 Noraziah Nordin,1 Mehran Fadaeinasab,3 Mohamad Ibrahim Noordin,1 Suzita Mohd Noor4 1Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; 2Medical Research Center, Jazan University, Jazan, Saudi Arabia; 3Department of Chemistry, 4Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia Abstract: Therapy that directly targets apoptosis and/or inflammation could be highly effective for the treatment of cancer. Murraya koenigii is an edible herb that has been traditionally used for cancer treatment as well as inflammation. Here, we describe that girinimbine, a carbazole alkaloid isolated from M. koenigii, induced apoptosis and inhibited inflammation in vitro as well as in vivo. Induction of apoptosis in human colon cancer cells (HT-29) by girinimbine revealed decreased cell viability in HT-29, whereas there was no cytotoxic effect on normal colon cells. Changes in mitochondrial membrane potential, nuclear condensation, cell permeability, and cytochrome c translocation in girinimbine-treated HT-29 cells demonstrated involvement of mitochondria in apoptosis. Early-phase apoptosis was shown in both acridine orange/propidium iodide and annexin V results. Girinimbine treatment also resulted in an induction of G0/G1 phase arrest which was further corroborated with the upregulation of two cyclin-dependent kinase proteins, p21 and p27. Girinimbine treatment activated apoptosis through the intrinsic pathway by activation of caspases 3 and 9 as well as cleaved caspases 3 and 9 which ended by triggering the execution pathway. Moreover, apoptosis was confirmed by downregulation of Bcl-2 and upregulation of Bax in girinimbine-treated cells. In addition, the key tumor suppressor protein, p53, was seen to be considerably upregulated upon girinimbine treatment. Induction of apoptosis by girinimbine was also evidenced in vivo in zebrafish embryos, with results demonstrating significant distribution of apoptotic cells in embryos after a 24-hour treatment period. Meanwhile, anti-inflammatory action was evidenced by the significant dose-dependent girinimbine inhibition of nitric oxide production in lipopolysaccharide/interferon-gamma-induced cells along with significant inhibition of nuclear factor-kappa B translocation from the cytoplasm to nucleus in stimulated RAW 264.7 cells. Girinimbine was also shown to have considerable antioxidant activity whereby 20 µg/mL of girinimbine was equivalent to 82.17±1.88 µM of Trolox. In mice with carrageenan-induced peritonitis, oral pretreatment with girinimbine helped limit total leukocyte migration (mainly of neutrophils), and reduced pro-inflammatory cytokine levels (interleukin-1beta and tumor necrosis factor-alpha) in the peritoneal fluid. These findings strongly suggest that girinimbine could act as a chemopreventive and/or chemotherapeutic agent by inducing apoptosis while suppressing inflammation. There is a potential for girinimbine to be further investigated for its applicability in treating early stages of cancer. Keywords: carbazole alkaloid, apoptosis, inflammation, chemopreventive, chemotherapeutic

Noraziah Nordin,1 Nazia Abdul Majid,2 Najihah Mohd Hashim,1 Mashitoh Abd Rahman,1 Zalila Hassan,3 Hapipah Mohd Ali3 1Department of Pharmacy, Faculty of Medicine, 2Institute of Biological Sciences, 3Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia Abstract: Enicosanthellum pulchrum is a tropical plant from Malaysia and belongs to the Annonaceae family. This plant is rich in isoquinoline alkaloids. In the present study, liriodenine, an isoquinoline alkaloid, was examined as a potential anticancer agent, particularly in ovarian cancer. Liriodenine was isolated by preparative high-performance liquid chromatography. Cell viability was performed to determine the cytotoxicity, whilst the detection of morphological changes was carried out by acridine orange/propidium iodide assay. Initial and late apoptosis was examined by Annexin V-fluorescein isothiocyanate and DNA laddering assays, respectively. The involvement of pathways was detected via caspase-3, caspase-8, and caspase-9 analyses. Confirmation of pathways was further performed in mitochondria using a cytotoxicity 3 assay. Apoptosis was confirmed at the protein level, including Bax, Bcl-2, and survivin, while interruption of the cell cycle was used for final validation of apoptosis. The result showed that liriodenine inhibits proliferation of CAOV-3 cells at 37.3 µM after 24 hours of exposure. Changes in cell morphology were detected by the presence of cell membrane blebbing, chromatin condensation, and formation of apoptotic bodies. Early apoptosis was observed by Annexin V-fluorescein isothiocyanate bound to the cell membrane as early as 24 hours. Liriodenine activated the intrinsic pathway by induction of caspase-3 and caspase-9. Involvement of the intrinsic pathway in the mitochondria could be seen, with a significant increase in mitochondrial permeability and cytochrome c release, whereas the mitochondrial membrane potential was decreased. DNA fragmentation occurred at 72 hours upon exposure to liriodenine. The presence of DNA fragmentation indicates the CAOV-3 cells undergo late apoptosis or final stage of apoptosis. Confirmation of apoptosis at the protein level showed overexpression of Bax and suppression of Bcl-2 and survivin. Liriodenine inhibits progression of the CAOV-3 cell cycle in S phase. These findings indicate that liriodenine could be considered as a promising anticancer agent. Keywords: Enicosanthellum pulchrum, liriodenine, ovarian cancer, CAOV-3, apoptosis