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Fulltext Effects of Vanadium on the Structural and Optical Properties of Borate Glasses Containing Er3+ and Silver Nanoparticles

Zaini NA, Mohamed SN, Mohamed Z

Materials (Basel), 2021 Jul 02;14(13).
PMID: 34279280 DOI: 10.3390/ma14133710

The erbium-vanadium co-doped borate glasses, embedded with silver nanoparticles (Ag NPs), were prepared to improve their optical properties for potential optical fiber and glass laser application. The borate glasses with composition (59.5-x) B2O3-20Na2O-20CaO-xV2O5-Er2O3-0.5AgCl (x = 0-2.5 mol%) were successfully prepared by conventional melt-quenching method. The structural properties of glass samples were investigated by XRD, TEM and by Fourier transform infrared (FTIR) spectroscopy while optical properties were carried out by UV-Vis spectroscopy by measuring optical absorption and the emission properties were investigated by photoluminescence spectroscopy. The XRD patterns confirmed the amorphous nature of the prepared glass samples whilst the FTIR confirmed the presence of VO4, VO5, BO3 and BO4 vibrations. UV-Vis-NIR absorption spectra reveal eight bands which were located at 450, 490, 519, 540, 660, 780, 980, and 1550 nm corresponding to transition of 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2, 4I11/2, and 4I13/2, respectively. The optical band gap (Eopt), Urbach energy and refractive index were observed to decrease, increase and increase, respectively, to the addition of vanadium. Under 800 nm excitation, three emission bands were observed at 516, 580 and 673 nm, which are represented by 2H11/2-4I15/2, 4S3/2-4I15/2 and 4F15/2-4I15/2, respectively. The excellent features of achieved results suggest that our findings may provide useful information toward the development of functional glasses.
Purification and characterization of membrane-bound polyphenoloxidase (mPPO) from Snake fruit [Salacca zalacca (Gaertn.) Voss]

Zaini NA, Osman A, Hamid AA, Ebrahimpour A, Saari N

Food Chem, 2013 Jan 15;136(2):407-14.
PMID: 23122078 DOI: 10.1016/j.foodchem.2012.08.034

Membrane-bound polyphenoloxidase (mPPO) an oxidative enzyme which is responsible for the undesirable browning reaction in Snake fruit (Salacca zalacca (Gaertn.) Voss) was investigated. The enzyme was extracted using a non-ionic detergent (Triton X-114), followed by temperature-induced phase partitioning technique which resulted in two separate layers (detergent-poor phase at the upper layer and detergent-rich phase at the lower layer). The upper detergent-poor phase extract was subsequently fractionated by 40-80% ammonium sulfate and chromatographed on HiTrap Phenyl Sepharose and Superdex 200 HR 10/30. The mPPO was purified to 14.1 folds with a recovery of 12.35%. A single prominent protein band appeared on native-PAGE and SDS-PAGE implying that the mPPO is a monomeric protein with estimated molecular weight of 38kDa. Characterization study showed that mPPO from Snake fruit was optimally active at pH 6.5, temperature 30°C and active towards diphenols as substrates. The K(m) and V(max) values were calculated to be 5.46 mM and 0.98 U/ml/min, respectively, when catechol was used as substrate. Among the chemical inhibitors tested, l-cysteine showed the best inhibitory effect, with an IC(50) of 1.3 ± 0.002 mM followed by ascorbic acid (1.5 ± 0.06 mM), glutathione (1.5 ± 0.07 mM), EDTA (100 ± 0.02 mM) and citric acid (186 ± 0.16 mM).
Commentary on article: Aerobic microbe community and necrophagous insects associated with decomposition of pig carrion poisoned with lead by Aneyo et al. (DOI: https://doi.org/10.1016/j.legalmed.2019.101638)

Zaini NA, Ivorra T, Azmiera N, Natasha NA, Heo CC

Leg Med (Tokyo), 2021 02;48:101818.
PMID: 33271415 DOI: 10.1016/j.legalmed.2020.101818
Reporting beetles in a mummified human corpse in Malaysia: Necrobia rufipes (Fabricius, 1781) (Coleoptera: Cleridae) and Dermestes maculatus De Geer, 1774 (Coleoptera: Dermestidae)

Ivorra T, Rahimi R, Zaini NA, Heo CC

Leg Med (Tokyo), 2023 May;62:102238.
PMID: 36913819 DOI: 10.1016/j.legalmed.2023.102238

This case study reports on two unrecorded Coleopteran species found together on a human corpse in Malaysia. The mummified human remains were discovered in a house in Selangor, Malaysia. The pathologist confirmed that the death was due to a traumatic chest injury. Maggots, beetles, and fly pupal casings were found mainly on the front part of the body. Empty puparia of Diptera were collected during the autopsy and identified later as the muscid Synthesiomyia nudiseta (van der Wulp, 1883) (Diptera: Muscidae). Also, the insect evidence received included larvae and pupae of Megaselia sp. (Diptera: Phoridae). According to the insect development data, the minimum postmortem period was estimated by the time to reach the pupal developmental stage (in days). The entomological evidence included the first record of Dermestes maculatus De Geer, 1774 (Coleoptera: Dermestidae) and Necrobia rufipes (Fabricius, 1781) (Coleoptera: Cleridae), which have not previously been recorded on human remains in Malaysia.
A pilot randomized control trial on the feasibility, acceptability, and initial effects of a digital-assisted parenting intervention for promoting mental health in Malaysian adolescents

Zulkefly NS, Dzeidee Schaff AR, Zaini NA, Mukhtar F, Dahlan R

Digit Health, 2024;10:20552076241249572.
PMID: 38665881 DOI: 10.1177/20552076241249572

OBJECTIVE: Online parenting interventions for enhancing child development, specifically mental health is relatively new in Malaysia. This pilot study tests the feasibility, acceptability, and initial effects of a universal digital-assisted parenting intervention (DaPI) in promoting mental health in adolescents by improving parental behaviors and self-efficacy.
METHODS: A two-arm pilot randomized controlled trial was conducted. Twenty-four mothers of adolescent aged 10 to 14 years from a non-clinical sample were recruited online and randomly allocated into two groups (intervention [DaPI] and waitlist-control [WLC]). Eight weekly sessions were delivered online via technological devices. Feasibility outcomes were based on the participants' engagement in DaPI and study retention. Primary (parental behaviors and self-efficacy) and secondary (adolescent mental health) outcomes were assessed using an online survey at baseline (T0), post-intervention (T1), and 1-month follow-up (T2). Data were analyzed using descriptive and inferential statistics and an intention-to-treat approach.
RESULTS: The DaPI was well received by the mothers. Retention was high (81.8%) in both groups and intervention adherence was excellent (91.6%). Within-group analyses showed a significant decrease in physical control at T2 and an increase in parental self-efficacy at T1 and T2 among the DaPI mothers. No significant differences were observed in adolescents' mental health at any time point. As for the WLC group, there were no significant differences in all the outcome variables across the three assessment moments. Between groups analyses revealed DaPI mothers had significant differences in proactive parenting at T1, and in positive reinforcement and lax control at T2. There were no significant differences in adolescents' mental health between the groups at any time point.
DISCUSSION: The DaPI is feasible and acceptable in the Malaysian context. Findings show promise regarding the initial effects of the DaPI. However, a larger RCT is needed to determine its effectiveness in promoting mental health of adolescents.
TRIAL REGISTRATION: https://www.irct.ir/; identifier: IRCT20211129053207N1.
Antibiotic resistance and determination of resistant genes among cockle (Anadara granosa) isolates of Vibrio alginolyticus

Shahimi S, Elias A, Abd Mutalib S, Salami M, Fauzi F, Mohd Zaini NA, et al.

Environ Sci Pollut Res Int, 2021 Aug;28(32):44002-44013.
PMID: 33846919 DOI: 10.1007/s11356-021-13665-4

A total of 24 strains of Vibrio alginolyticus were isolated from cockles (Anadara granosa) and identified for VibA and gyrB genes. All V. alginolyticus isolates were then tested against nine different antibiotics. In this study, the highest percentage of antibiotic resistance was obtained against penicillin (37.50%), followed by ampicillin, vancomycin (12.50%) and erythromycin (8.33%). All of V. alginolyticus isolates were susceptible against streptomycin, kanamycin, tetracycline, chloramphenicol and sulfamethoxazole. Polymerase chain reaction (PCR) assay has confirmed the presence of four antibiotic resistance genes of penicillin (pbp2a), ampicillin (blaOXA), erythromycin (ermB) and vancomycin (vanB). Out of 24 V. alginolyticus isolates, 2 isolates possessed the tdh-related hemolysin (trh) (strains VA15 and VA16) and none for the thermostable direct hemolysin (tdh) gene. Both strains of the tdh-related hemolysin (trh) were susceptible to all antibiotics tested. The multiple antibiotic resistance (MAR) index ranging between 0.2 and 0.3 with 5 antibiograms (A1-A5) was observed. Combination of enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and antibiotic resistance indicated 18 genome types which showed genetic heterogeneity of those V. alginolyticus isolates. The results demonstrated the presence of V. alginolyticus strain found in cockles can be a potential risk to consumers and can contribute to the deterioration of human health in the study area. Thus, it is essential for local authority to provide the preventive measures in ensuring the cockles are safe for consumption.
Antimicrobial activity of Lactobacillus spp. isolated from fermented foods and their inhibitory effect against foodborne pathogens

Hussein AO, Khalil K, Mohd Zaini NA, Al Atya AK, Aqma WS

PeerJ, 2025;13:e18541.
PMID: 39790459 DOI: 10.7717/peerj.18541

Lactic acid bacteria (LAB), known for their health benefits, exhibit antimicrobial and antibiofilm properties. This study investigated the cell-free supernatant (CFS) of Lactobacillus spp., particularly L. plantarum KR3, against the common foodborne pathogens S. aureus, E. coli and Salmonella spp. Lactobacillus strains were isolated from cheese, pickles and yoghurt. They were then identified by morphological, physiological and biochemical characteristics and confirmed by 16S rRNA gene sequencing. Culture supernatants from seven lactobacilli isolates showed varying inhibitory activities. Notably, L. plantarum KR3 and L. pentosus had the highest bacteriocin gene counts. L. plantarum KR3 CFS demonstrated significant antibacterial activity, with inhibition zones of 20 ± 0.34 mm for S. aureus, 23 ± 1.64 mm for E. coli, and 17.1 ± 1.70 mm for Salmonella spp. The CFS also exhibited substantial antibiofilm activity, with 59.12 ± 0.03% against S. aureus, 83.50 ± 0.01% against E. coli, and 60. ± 0.04% against Salmonella spp., which were enhanced at the minimum inhibitory concentration (MIC). These results highlighted the potential of L. plantarum KR3 in antimicrobial applications, however, further research is needed to evaluate its viability and functional properties for probiotic use. Additionally, the CFS demonstrated exceptional thermal stability, reinforcing its promise as an antimicrobial agent.
Level of chemical and microbiological contaminations in chili bo (paste)

Zaini NA, Harith HH, Olusesan AT, Zulkifli AH, Bakar FA, Osman A, et al.

J Food Prot, 2010 Mar;73(3):541-6.
PMID: 20202342

The objective of this study was to determine the level of preservatives and microbiological loads in various brands of commercially available chili bo (paste). Fifteen different brands of chili bo obtained from the local market and hypermarkets were analyzed for pH, moisture and benzoic acid content, microbiological loads (aerobic, anaerobic, aerobic spores, and fungi), and thermophilic microorganisms. Results showed that both moisture content and pH vary among samples. The concentrations of benzoic acid detected in chili bo were found to be in the range of 537 to 5,435 mg/kg. Nine of fifteen brands were found to exceed the maximum level permitted by the Malaysian Food Law in accordance with the Codex Alimentarius (1,000 mg/kg for benzoic acid). An apparent correlation between benzoic acid concentration and microbiological loads present in the chili bo was observed. The microbiological loads were found to be relatively low in the end products containing high amounts of benzoic acid. The heat-resistant (70 to 80 degrees C) microorganisms present in chili bo were identified as Ochrobacterum tritici, Stenotrophomonas rhizophila, Microbacterium maritypicum, Roseomonas spp., CDC group II-E subgroup A, Flavimonas oryzihabitans, and Pseudomonas aeruginosa, with M. maritypicum being the most frequently found (in 9 of 15 samples) microorganism. Most of these identified microorganisms were not known to cause foodborne illnesses.
Fulltext Optimisation of fermentation conditions for the production of gamma-aminobutyric acid (GABA)-rich soy sauce

Shin Yee C, Ilham Z, Cheng A, Abd Rahim MH, Hajar-Azhari S, Yuswan MH, et al.

Heliyon, 2024 Jul 15;10(13):e33147.
PMID: 39040394 DOI: 10.1016/j.heliyon.2024.e33147

This study addresses the challenge of enhancing gamma-aminobutyric acid (GABA) content in soy sauce through optimized fermentation condition. Using a multiple starter culture, consisting of Aspergillus oryzae strain NSK, Bacillus cereus strain KBC and Tetragenococcus halophilus strain KBC, the incubation conditions including the percentage of bacterial inoculum (10, 15 and 20 %), pH (3, 5 and 7) and agitation speed (100, 150 and 200 rpm) were optimized through Response Surface Methodology (RSM). Under the optimal conditions (20 % inoculum, pH 7 and stirring at 100 rpm), the multiple starter culture generated 128.69 mg/L of GABA after 7 days and produced 239.08 mg/L of GABA after 4 weeks of fermentation, which is 36 % higher than under non-optimized conditions (153.48 mg/L). Furthermore, sensory analysis revealed high consumer acceptance of the fermented soy sauce than the control (soy sauce without any treatment and additional bacteria) and commercial soy sauce. Consumers indicated that the starter culture offered an improved umami taste and reduced bitter, sour and salty flavours compared to the commercial product. Under optimal fermentation conditions determined by RSM statistical analysis, the multiple starter culture is able to produce high levels of GABA and is more likely to be accepted by consumers. The findings of this research have the potential to impact the food sector by offering a functional soy sauce with added health benefits and also being well-received by consumers.
Fulltext A narrative action on the battle against hunger using mushroom, peanut, and soybean-based wastes

Mohd Zaini NA, Azizan NAZ, Abd Rahim MH, Jamaludin AA, Raposo A, Raseetha S, et al.

Front Public Health, 2023;11:1175509.
PMID: 37250070 DOI: 10.3389/fpubh.2023.1175509

Numerous generations have been affected by hunger, which still affects hundreds of millions of people worldwide. The hunger crisis is worsening although many efforts have been made to minimize it. Besides that, food waste is one of the critical problems faced by most countries worldwide. It has disrupted the food chain system due to inefficient waste management, while negatively impacting the environment. The majority of the waste is from the food production process, resulting in a net zero production for food manufacturers while also harnessing its potential. Most food production wastes are high in nutritional and functional values, yet most of them end up as low-cost animal feed and plant fertilizers. This review identified key emerging wastes from the production line of mushroom, peanut, and soybean (MPS). These wastes (MPS) provide a new source for food conversion due to their high nutritional content, which contributes to a circular economy in the post-pandemic era and ensures food security. In order to achieve carbon neutrality and effective waste management for the production of alternative foods, biotechnological processes such as digestive, fermentative, and enzymatic conversions are essential. The article provides a narrative action on the critical potential application and challenges of MPS as future foods in the battle against hunger.