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γ-Aminobutyric acid production by selected lactic acid bacteria isolate of an Indonesian indigenous fermented buffalo milk (dadih) origin

Harnentis H, Nurmiati N, Marlida Y, Adzitey F, Huda N

Vet World, 2019 Aug;12(8):1352-1357.
PMID: 31641319 DOI: 10.14202/vetworld.2019.1352-1357

Aim: This study aimed at optimizing γ-aminobutyric acid (GABA) production using lactic acid bacteria (LAB) of an Indonesian indigenous fermented buffalo milk (dadih) origin. This study utilized LAB previously cultured from dadih that has the ability to produce GABA.
Materials and Methods: The study started with the identification of selected LAB by 16S rRNA, followed by optimization of GABA production by culture conditions using different initial pH, temperature, glutamate concentration, incubation time, carbon, and nitrogen sources. 16S rRNA polymerase chain reaction and analysis by phylogenetic were used to identify Lactobacillus plantarum (coded as N5) responsible for the production of GABA.
Results: GABA production by high-performance liquid chromatography was highest at pH of 5.5, temperature of 36°C, glutamate concentration of 500 mM, and incubation time of 84 h. Peptone and glucose served as the nitrogen and carbon sources, respectively, whereas GABA was produced at optimum fermentation condition of 211.169 mM.
Conclusion: Production of GABA by L. plantarum N5 was influenced by initial pH of 5.5, glutamic acid concentration, nitrogen source, glucose as carbon source, and incubation temperature and time.

Matched MeSH terms: Temperature
Risk factors associated with viral nervous necrosis in hybrid groupers in Malaysia and the high similarity of its causative agent nervous necrosis virus to reassortant red-spotted grouper nervous necrosis virus/striped jack nervous necrosis virus strains

Ariff N, Abdullah A, Azmai MNA, Musa N, Zainathan SC

Vet World, 2019 Aug;12(8):1273-1284.
PMID: 31641308 DOI: 10.14202/vetworld.2019.1273-1284

Background and Aim: Viral nervous necrosis (VNN) is a serious disease of several marine fish species. VNN causes 100% mortality in the larval stages, while lower losses have been reported in juvenile and adult fish. This study aimed to detect the occurrence of VNN while identifying its associated risk factors and the genotypes of its causative agent in a hybrid grouper hatchery in Malaysia.
Materials and Methods: A batch of newly hatched hybrid grouper fry (Epinephelus fuscoguttatus × Epinephelus lanceolatus) were followed from the larval stage to market size. Samples of the hybrid groupers, water, live feed, and artificial fish pellets were collected periodically from day 0 to 180 in the hybrid grouper hatchery. Reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR amplifications were carried out on VNN-related sequences. The phylogenetic tree including the sampled causative agent of VNN was inferred from the coat protein genes from all known Betanodavirus species using Molecular Evolutionary Genetics Analysis (MEGA). Pearson's correlation coefficient values were calculated to determine the strength of the correlation between the presence of VNN in hybrid grouper samples and its associated risk factors.
Results: A total of 113 out of 146 pooled and individual samples, including hybrid grouper, water, and artificial fish pellet samples, demonstrated positive results in tests for the presence of VNN-associated viruses. The clinical signs of infection observed in the samples included darkened skin, deformation of the backbone, abdominal distension, skin lesions, and fin erosion. VNN was present throughout the life stages of the hybrid groupers, with the first detection occurring at day 10. VNN-associated risk factors included water temperature, dissolved oxygen content, salinity, ammonia level, fish size (adults more at risk than younger stages), and life stage (age). Detection of VNN-associated viruses in water samples demonstrated evidence of horizontal transmission of the disease. All the nucleotide sequences found in this study had high nucleotide identities of 88% to 100% to each other, striped jack nervous necrosis virus (SJNNV), and the reassortant strain red-spotted grouper NNV/SJNNV (RGNNV/SJNNV) isolate 430.2004 (GenBank accession number JN189932.1) (n=26). The phylogenetic analysis showed that quasispecies was present in each VNN-causing virus-positive sample, which differed based on the type of sample and life stage.
Conclusion: This study was the first to confirm the existence of a reassortant strain (RGNNV/SJNNV) in hybrid groupers from Malaysia and Southeast Asia. However, the association between the mode of transmission and the risk factors of this virus needs to be investigated further to understand the evolution and potential new host species of the reassortant strain.

Matched MeSH terms: Temperature
Interaction study of peptide-PAMAM as potential bio-nanogate for detecting anti-hepatitis B surface antigen

Syamila N, Syahir A, Ikeno S, Tan WS, Ahmad H, Ahmad Tajudin A

Colloids Surf B Biointerfaces, 2020 Jan 01;185:110623.
PMID: 31735420 DOI: 10.1016/j.colsurfb.2019.110623

Bio-nanogate involves synthesized or natural molecules as a 'gate' towards bioreceptors and responds upon the presence of targeted analytes in nanoscale dimension. Development of bio-nanogate improves analyte selectivity and signal response across various types of biosensors. The versatility of PAMAM dendrimers to form conjugates with guest molecules, such as proteins can be utilized in forming a bio-nanogate. PAMAM interaction with peptide bioreceptor for antibody detection is of interest in this study. This study investigated the interaction of synthesized immunogenic 'a' determinant (aD) region of hepatitis B virus surface antigen (HBsAg) with PAMAM G4 and anti-HBsAg antibody, as a potential bio-nanogate for anti-HBsAg detection. The aD peptide fused with maltose binding protein (MBP), was confirmed with Western blotting. Nano-Differential Scanning Fluorimetry (nano-DSF) study revealed that the interaction of MBP-aD with anti-HBsAg indicated a higher thermal stability as compared to its interaction with PAMAM G4. Electrochemical impedance spectroscopy showed that a higher binding constant of MBP-aD interaction with anti-HBsAg (0.92 μM-1) was observed at maximum saturation, as compared with PAMAM G4 (0.07 μM-1). Thermodynamic parameters demonstrated that MBP-aD interacted with anti-HBsAg and PAMAM G4, through van der Waals and hydrogen bonding. These analyses suggest that the weak interaction of MBP-aD and PAMAM G4 may form a potential bio-nanogate. It is hypothesized that the presence of anti-HBsAg has a higher affinity towards MBP-aD which may displace PAMAM G4 in the anti-HBsAg detection system. This interaction study is crucial as an initial platform of using peptide-PAMAM as a bio-nanogate in an antibody detection system.

Matched MeSH terms: Temperature
Ultrasound-assisted weak-acid hydrolysis of crystalline starch nanoparticles for chemical enhanced oil recovery

Agi A, Junin R, Arsad A, Abbas A, Gbadamosi A, Azli NB, et al.

Int J Biol Macromol, 2020 Apr 01;148:1251-1271.
PMID: 31760018 DOI: 10.1016/j.ijbiomac.2019.10.099

Ascorbic acid was used for the first time to synthesize crystalline starch nanoparticles (CSNP). The physical properties of the CSNP were investigated. Rheological properties of the crystalline starch nanofluid (CSNF) were compared with native cassava starch (CS) and commercial polymer xanthan. Interfacial properties of the CSNF at the interface of oil and water (O/W) were investigated at different concentrations and temperatures. Wettability alteration efficiency of CSNF on oil-wet sandstone surface was investigated using the sessile drop method. Core flooding experiment was conducted at reservoir conditions. The methods were effective in producing spherical and polygonal nanoparticles with a mean diameter of 100 nm and increased in crystallinity of 7%. Viscosity increased with increase in surface area and temperature of the CSNF compared to a decrease in viscosity as the temperature increases for xanthan. Interfacial tension (IFT) decreased with increase in concentration of CSNF, electrolyte and temperature. The results show that CSNF can change the wettability of sandstone at low concentration, high salinity and elevated temperature. Pressure drops data shows stability of CSNF at 120 °C. The formation of oil bank was enough to increase oil recovery by 23%.

Matched MeSH terms: Temperature
Fulltext Utilization of Neem Leaf Extract on Biosynthesis of Iron Oxide Nanoparticles

Zambri NDS, Taib NI, Abdul Latif F, Mohamed Z

Molecules, 2019 Oct 22;24(20).
PMID: 31652583 DOI: 10.3390/molecules24203803

The present work reports the successful synthesis of biosynthesized iron oxide nanoparticles (Fe3O4-NPs) with the use of non-toxic leaf extract of Neem (Azadirachta indica) as a reducing and stabilizing agent. The successful synthesis was confirmed by infrared spectra analysis with strong peak observed between 400-600 cm-1 that corresponds to magnetite nanoparticles characteristics. X-ray diffraction (XRD) analysis revealed that iron oxide nanoparticles were of high purity with crystalline cubic structure phases in nature. Besides, the average size of magnetite nanoparticles was observed to be 9-12 nm with mostly irregular shapes using a transmission electron microscope (TEM) and was supported by field emission scanning electron microscope (FESEM). Energy dispersive X-ray analysis shown that the elements iron (Fe) and oxygen (O) were present with atomic percentages of 33.29% and 66.71%, respectively. From the vibrating sample magnetometer (VSM) analysis it was proven that the nanoparticles exhibited superparamagnetic properties with a magnetization value of 73 emu/g and the results showed superparamagnetic behavior at room temperature, suggesting potential applications for a magnetic targeting drug delivery system.

Matched MeSH terms: Temperature
Isolation and characterization of Enterococcus faecium DSM 20477 with ability to secrete antimicrobial substance for the inhibition of oral pathogen Streptococcus mutans UKMCC 1019

Ng ZJ, Zarin MA, Lee CK, Phapugrangkul P, Tan JS

Arch Oral Biol, 2020 Feb;110:104617.
PMID: 31794906 DOI: 10.1016/j.archoralbio.2019.104617

Streptococcus mutans and Candida albicans are the main oral pathogens which contribute to dental caries that affects all ages of human being.
OBJECTIVES: This study focuses on the potential of crude cell free supernatant (CCFS) from lactic acid bacteria (LAB) to inhibit of the growth of S. mutans UKMCC 1019.
DESIGN: A total of 61 CCFS from LAB strains were screened for their inhibitory ability against S. mutans UKMCC 1019 by broth microdilution method. The selected LAB with highest antimicrobial activity was identified and its CCFS was characterized for pH stability, temperature tolerance, enzyme sensitivity, metabolism of carbohydrates, enzymatic activities and antimicrobial activity against S. mutans UKMCC 1019 and C. albicans UKMCC 3001 by well diffusion assay. The effect of CCFS on cell structure of S. mutans UKMCC 1019 was observed under transmission electron microscopy (TEM).
RESULTS: The CCFS from isolate CC2 from Kimchi showed the highest inhibition against S. mutans UKMCC 1019, which was 76.46 % or 4406.08 mm2/mL and it was identified to be most closely related to Enterococcus faecium DSM 20477 based on 16 s rRNA sequencing. The CCFS of E. faecium DSM 20477 had high tolerance to acidic and alkaline environment as well as high temperature. It also shows high antifungal activities against C. albicans UKMCC 3001 with 2362.56 mm2/mL. Under TEM, the cell walls and the cytoplasm membrane of S. mutans UKMCC 1019 were disrupted by the antimicrobial substance, causing cell lysis.
CONCLUSIONS: Hence, the CCFS from E. faecium DSM 20477 is a potential bacteriocin in future for the treatment of dental caries.

Matched MeSH terms: Temperature
Production of uv-curable palm oil resins/oligomers using laboratory scale and pilot scale systems

Rida Tajau, Mohd hilmi Mahmood, Mek Zah Salleh, Khairul Zaman Mohd dahlan, Rosley Che ismail, Sharilla Muhammad Faisal, et al.

Sains Malaysiana, 2013;42:459-467.

In recent years, there are growing trends in using palm oil as raw materials in radiation curable resins production. In this study, the acrylated palm oil resins i.e. the EPOLA (epoxidized palm oil acrylate) and the POBUA (palm oil based urethane acrylate) were synthesized using two different systems, i.e. the 25 liter pilot scale reactor synthesis system and the 2 liter (L) laboratory scale reactor synthesis system through chemical processes known as acrylation and isocyanation. In this
paper, the property of the acrylated resins which were produced by these two systems were evaluated and compared between each other. Their properties were characterized using the Fourier transform infrared (FTIR) spectrophotometer for functional group identification; the gel permeation chromatography (GPC) for molecular weight (Mw) determination, the Brookfield viscometer for viscosity measurements, the acid values (AV) and the oxirane oxygen contents (OOC) analysis. As a result, the production process for both the 2 L and 25 L reactor system were found to be time consuming and the main advantages for the 25 L reactor was its higher productivity as compared with the 2 L reactor system with the same synthesis process parameters i.e. the temperatures and the experimental methods. Besides that, the 25 L reactor synthesis
process was found to be safe, easy to control and served unpolluted process to the environments. The final products, the acrylated palm oil resins were formulated into ultraviolet (UV) curable compounds before subjecting them under UVirradiation. As a result, the UV-curable palm oil resins showed potential uses as pressure sensitive adhesives, printing inks including overprint varnishes (OPV) and coatings.

Matched MeSH terms: Temperature
Synthesis, characterization and dna binding studies of [ruthenium(ii)(bpy)2 l]2+ where l are derivatives of imidazo[4,5-f]-1,10-phenanthrolines

Ting T, Crouse K, Ahmad H

Sains Malaysiana, 2015;44:619-628.

Three novel ruthenium(II) complexes of the general formula [Ru(II)(bpy)2
L]2+ were synthesized, where L =
1,10-phenanthroline derivatives of position 2 imidazole having 3,4-didecyloxy-phenyl (ddip), 3,4-ditetradecyloxy-phenyl
(dtip) and 3,4-dihexadecyloxy-phenyl (dhip). All complexes were characterized by elemental analysis, 1
H-NMR and ESI-MS.
Their photophysical properties have also been studied by UV-visible spectroscopy and fluorescence spectroscopy. The
complexes exhibit Ru(II) metal centered emission at approximately 610 nm in acetonitrile solution at room temperature. DNA
binding studies were carried out by UV-visible titration, luminescence titration and viscosity studies. The results indicated
that [Ru(bpy)2
(ddip)]2+ binds to CT-DNA by partial intercalation mode, while [Ru(bpy)2
(dtip)]2+ and [Ru(bpy)2
(dhip)]2+
bind intercalatively via extended ligands.

Matched MeSH terms: Temperature
Water quality status of selected rivers in Kota Marudu, Sabah, Malaysia and its suitability for usage

Ahmad Zaharin Aris, Wan YL, Sarva MP, Mohd Kamil Yusoff, Muhamma Firuz Ramli, Hafizan Juahir

Sains Malaysiana, 2014;43:377-388.

The water chemistry of selected rivers in Kota Marudu, Sabah was studied based on the major ion chemistry and its suitability for drinking and irrigation purposes. Ten sampling stations were selected and water samples were collected from each station to assess its chemical properties. The physico-chemical variables including temperature, electrical conductivity (EC), total dissolved solids (TDS), salinity, dissolved oxygen (DO), pH, turbidity, ammoniacal-nitrogen (NH3-N), biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solid (TSS) were measured. The cations (K, Mg, Ca, Na) were analyzed by ICP-MS. Most of the variables were within the drinking water quality standards stipulated by the World Health Organization (WHO) and the Ministry of Health (MOH), Malaysia except for turbidity. Sodium adsorption ratio (SAR) and salinity hazard were calculated to identify the suitability of the water as irrigation water. The Wilcox diagram classifies that only 10% of samples are not suitable for the purpose of irrigation. The overall results showed that most of the rivers in Kota Marudu are still in a clean condition and suitable for drinking and irrigation purposes except for Sumbilingan River, which is considered as slightly polluted. The results are supported by the hierarchical cluster analysis as the stations were grouped into two groups; low and high pollution intensities. This preliminary result can update the baseline data of selected water quality parameters in the Kota Marudu and could serve as tool for assisting relevant government bodies in regulating the water resources policies in the future.

Matched MeSH terms: Temperature
Influence and characteristics of Bacillus stearothermophilus in ammonia reduction during layer manure composting

Wang Y, Bi L, Liao Y, Lu D, Zhang H, Liao X, et al.

Ecotoxicol Environ Saf, 2019 Sep 30;180:80-87.
PMID: 31078019 DOI: 10.1016/j.ecoenv.2019.04.066

Ammonia emissions is an important issue during composting because it can cause secondary pollution and a significant of nitrogen loss. Based on research adding Bacillus stearothermophilus can reduce ammonia emissions during composting because it can use sugar in organic matter fermentation to produce organic acids over 50 °C. This study conducted the batch experiments by adding different concentrations of Bacillus stearothermophilus to reduce the ammonia emissions and find out its characteristic during layer manure composting by using an aerobic composting reactor with sawdust as a bulking agent. The results show that the application of Bacillus stearothermophilus can accelerate the rate of temperature and significantly decrease pH, the warming period was 2 days in the treatment with Bacillus stearothermophilus, while it was 4 days in the treatment without Bacillus stearothermophilus. Ammonia emissions were mainly occurred in warming and high temperature period during composting. The ammonia emissions in the treatment with 8.00 g/kg initial Bacillus stearothermophilus were significantly lower than the other lower Bacillus stearothermophilus treatment and control during composting (p  0.05). MiSeq System Sequencing results find that the addition of Bacillus stearothermophilus changed the bacterial community structure under warming and high-temperature periods during composting, increased the relative abundance of lactic acid bacillus and nitrification bacteria. Therefore, the reason for the low ammonia emission in 8.00 g/kg initial Bacillus stearothermophilus treatments might be not only due to the Bacillus stearothermophilus itself, but also Bacillus stearothermophilus can change the indigenous microorganism community, including increase the relative content of lactic acid Bacillus and nitrification bacteria, thus reducing the pH and promoting nitrification, and reducing ammonia emissions.

Matched MeSH terms: Temperature
Optimization of Enzymatic Hydrolysis of tilapia muscle (Oreochromis niloticus) using Response Surface Methodology (RSM)

Jumardi Roslan, Siti Mazlina Mustapa Kamal, Khairul Faezah Md. Yunos, Norhafizah Abdullah

Sains Malaysiana, 2014;43:1715-1723.

Fish protein hydrolysate was prepared from tilapia muscle using commercial Alcalase enzyme. Optimization of enzymatic hydrolysis process for preparing tilapia muscle protein hydrolysates (TMPH) was performed by employing central composite design (CCD) method of response surface methodology (RSM). O-phtaldialdehyde (OPA) method was employed to calculate the degree of hydrolysis (DH), which is the key parameter for monitoring the reaction of protein hydrolysis. The suggested model equation was proposed based on the effects of pH, temperature, substrate concentration and enzyme concentration on the DH. Optimum enzymatic hydrolysis conditions using Alcalase enzyme were obtained at pH7.5, temperature of 50oC, substrate concentration of 2.5% and enzyme concentration of 4.0%. Under these conditions, the highest value of the DH was achieved at 25.16% after hydrolysing at 120 min. The TMPH was further assessed for their nutritional value with respect to chemical and amino acid compositions. Molecular weight distributions of TMPH were characterized by SDS-PAGE. TMPH contains moderate amount of protein (28.14%) and good nutritive value with respect to the higher total amino acid composition (267.57 mg/g). Glutamic acid, aspartic acid and lysine were the most abundant amino acids present in TMPH with values 42.68, 29.16 and 26.21 mg/g, respectively. Protein hydrolysates from tilapia muscle containing a desirable peptide with low molecular weight which may potentially to be used as functional food products.

Matched MeSH terms: Temperature
Biodiesel production via transesterification of palm oil using NaOH/Al2O3 catalysts

Taufiq-Yap YH, Nurul Fitriyah Abdullah, Mahiran Basri

Sains Malaysiana, 2011;40:1179-1186.

Due to the increase in price of petroleum and environmental concerns, the search for alternative fuels has gained importance. In this work, biodiesel production by transesterification of palm oil with methanol has been studied in a heterogeneous system using sodium hydroxide loaded on alumina (NaOH/Al2O3). NaOH/Al2O3 catalyst was prepared by impregnation of alumina with different amount of an aqueous solution of sodium hydroxide followed by calcination in air for 3 h. The prepared catalysts were then characterized by using x-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), Brunner-Emmett-Teller surface area measurement (BET), scanning electron microscopy (SEM) and temperature-programmed desorption of CO2 (CO2-TPD). Moreover, the dependence of the conversion of palm oil on the reactions variables such as the molar ratio of methanol/oil, the amount of catalysts used, reaction temperatures and reaction times were performed. The conversion of 99% was achieved under the optimum reaction conditions. The biodiesel obtained was characterized by FT-IR and the pour point was measured.

Matched MeSH terms: Temperature
Selective adsorption and recovery of volatile fatty acids from fermented landfill leachate by activated carbon process

Talebi A, Razali YS, Ismail N, Rafatullah M, Azan Tajarudin H

Sci Total Environ, 2020 Mar 10;707:134533.
PMID: 31865088 DOI: 10.1016/j.scitotenv.2019.134533

An adsorption-desorption process was applied on fermented landfill leachate to adsorb and recover acetic and butyric acid, using activated carbon. In this study, the first, volatile fatty acids adsorption process from fermented leachate was optimized, by investigating various affecting factors such as pH, time, agitation speed, activated carbon dosage, and temperature. The optimum condition for maximum adsorption of 88.94% acetic acid and 98.53% butyric acid, was 19.79 %wt activated carbon dosage, 40.00 rpm of agitation speed, in 9.45 °C and contact time of 179.89 h, while the pH of the substrate was kept fixed at pH:3.0. Results of X-ray fluorescence (XRF) spectrometry, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and zeta potential revealed that carbon is the dominant component in the adsorbent with a significant effect to remove organic impurities, and it was observed that the activated carbon after the adsorption process showed an amorphous structure peak with a large internal surface area and pore volume. The results exposed that the adsorption on the surface of activated carbon was due to the chemisorption, and the chemisorption mechanism was supported by covalent bonding. The kinetic study displayed excellent fit to Pseudo-second order kinetics model. The second phase of this study was to recover the adsorbed VFAs using multistage desorption unit, in which application of deionized water and ethanol (as desorption agents) resulted in 89.1% of acetic acid and 67.8% of the butyric acid recovery.

Matched MeSH terms: Temperature
First Report of Ralstonia solanacearum Race 2 Biovar 1 Causing Moko Disease of Banana in Malaysia

Zulperi D, Sijam K

Plant Dis, 2014 Feb;98(2):275.
PMID: 30708756 DOI: 10.1094/PDIS-03-13-0321-PDN

During March 2011 to June 2012, 50 banana plants of cultivar Musa × paradisiaca 'Horn' with Moko disease symptoms were randomly sampled in 12 different locations of 5 outbreak states in Peninsular Malaysia comprising Kedah, Selangor, Pahang, Negeri Sembilan, and Johor, with disease incidence exceeding 90% in some severely affected plantations. The disease symptoms observed in the infected plants included yellowing and wilting of the oldest leaves, which became necrotic, and eventually led to their dieback or collapse. The pulp of banana fruits also became discolored and exuded bacterial ooze. Vascular tissues in pseudostems were discolored. Fragments from symptomatic plant samples were excised and cultured on Kelman's-tetrazolium salt (TZC) medium. Twenty positive samples produced fluidal colonies that were either entirely white or white with pink centers after incubation for 24 to 48 h at 28°C on Kelman's-TZC medium and appeared as gram-negative rods after Gram staining. They were also positive for potassium hydroxide (KOH), Kovacs oxidase, and catalase tests, but negative for utilization of disaccharides and hexose alcohols, which are characteristics of biovar 1 Ralstonia solanacearum. For the pathogenicity test, 30 μl of 108 CFU/ml bacterial suspension of three selected virulent strains were injected into banana (Musa × paradisiaca 'Horn') leaves explants grown in plastic pots of 1,440 cm3 volume in a greenhouse, with temperature range from 26 to 35°C. Leaves that were infiltrated with sterile distilled water served as a negative control. Inoculations with all isolates were performed in three replications, as well as the uninoculated control leaves explants. The inoculated plants produced the same symptoms as observed on naturally diseased samples, whereas control plants remained asymptomatic. Strain cultures were re-isolated and possessed the morphological and biochemical characteristics as previously described. PCR amplification using race 2 R. solanacearum primers ISRso19-F (5'-TGGGAGAGGATGGCGGCTTT-3') and ISRso19-R (5'-TGACCCGCCTTTCGGTGTTT-3') (3) produced a 1,900-bp product from DNA of all bacterial strains. BLAST searches resulted that the sequences were 95 to 98% identical to published R. solanacearum strain race 2 insertion sequence ISRso19 (GenBank Accession No. AF450275). These genes were later deposited in GenBank (KC812051, KC812052, and KC812053). Phylotype-specific multiplex PCR (Pmx-PCR) and Musa-specific multiplex PCR (Mmx-PCR) were performed to identify the phylotype and sequevar of all isolates (4). Pmx-PCR showed that all isolates belonged to phylotype II, whereas Mmx-PCR showed that they belonged to phylotype II sequevar 4 displaying 351-bp amplicon. Although there were previously extensive studies on R. solanacearum associated with bacterial wilt disease of banana crops in Malaysia, none related to Moko disease has been reported (1,2). The result has a great importance to better understand and document R. solanacearum race 2 biovar 1, since banana has been identified as the second most important commercial fruit crop with a high economic value in Malaysia. References: (1) R. Khakvar et al. Plant Pathol. J. 7:162, 2008. (2) R. Khakvar et al. Am. J. Agri. Biol. Sci. 3:490, 2008. (3) Y. A. Lee and C. N. Khor. Plant Pathol. Bull. 12:57, 2003. (4) P. Prior et al. Pages 405-414 in: Bacterial Wilt Disease and the Ralstonia solanacearum Species Complex. The American Phytopathological Society, St. Paul, MN, 2005.

Matched MeSH terms: Temperature
Fulltext Synthesis and characterizations of o-nitrochitosan based biopolymer electrolyte for electrochemical devices

Rahman NA, Abu Hanifah S, Mobarak NN, Su'ait MS, Ahmad A, Shyuan LK, et al.

PLoS One, 2019;14(2):e0212066.
PMID: 30768616 DOI: 10.1371/journal.pone.0212066

For the past decade, much attention was focused on polysaccharide natural resources for various purposes. Throughout the works, several efforts were reported to prepare new function of chitosan by chemical modifications for renewable energy, such as fuel cell application. This paper focuses on synthesis of the chitosan derivative, namely, O-nitrochitosan which was synthesized at various compositions of sodium hydroxide and reacted with nitric acid fume. Its potential as biopolymer electrolytes was studied. The substitution of nitro group was analyzed by using Attenuated Total Reflectance Fourier Transform Infra-Red (ATR-FTIR) analysis, Nuclear Magnetic Resonance (NMR) and Elemental Analysis (CHNS). The structure was characterized by X-ray Diffraction (XRD) and its thermal properties were examined by using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Whereas, the ionic conductivity of the samples was analyzed by electrochemical impedance spectroscopy (EIS). From the IR spectrum results, the nitro group peaks of O-nitrochitosan, positioned at 1646 and 1355 cm-1, were clearly seen for all pH media. At pH 6, O-nitrochitosan exhibited the highest degree of substitution at 0.74 when analyzed by CHNS analysis and NMR further proved that C-6 of glucosamine ring was shifted to the higher field. However, the thermal stability and glass transition temperatures were decreased with acidic condition. The highest ionic conductivity of O-nitrochitosan was obtained at ~10-6 cm-1. Overall, the electrochemical property of new O-nitrochitosan showed a good improvement as compared to chitosan and other chitosan derivatives. Hence, O-nitrochitosan is a promising biopolymer electrolyte and has the potential to be applied in electrochemical devices.

Matched MeSH terms: Temperature
Lactobacillus paracasei PS23 reduced early-life stress abnormalities in maternal separation mouse model

Liao JF, Hsu CC, Chou GT, Hsu JS, Liong MT, Tsai YC

Benef Microbes, 2019 Apr 19;10(4):425-436.
PMID: 30882243 DOI: 10.3920/BM2018.0077

Maternal separation (MS) has been developed as a model for inducing stress and depression in studies using rodents. The concept of the gut-brain axis suggests that gut health is essential for brain health. Here, we present the effects of administration of a probiotic, Lactobacillus paracasei PS23 (PS23), to MS mice against psychological traits including anxiety and depression. The administration of live and heat-killed PS23 cells showed positive behavioural effects on MS animals, where exploratory tendencies and mobility were increased in behavioural tests, indicating reduced anxiety and depression compared to the negative control mice (P<0.05). Mice administered with both live and heat-killed PS23 cells also showed lower serum corticosterone levels accompanied by higher serum anti-inflammatory interleukin 10 (IL-10) levels, compared to MS separated mice (P<0.05), indicating a stress-elicited response affiliated with increased immunomodulatory properties. Assessment of neurotransmitters in the brain hippocampal region revealed that PS23 affected the concentrations of dopaminergic metabolites differently than the control, suggesting that PS23 may have improved MS-induced stress levels via neurotransmitter pathways, such as dopamine or other mechanisms not addressed in the current study. Our study illustrates the potential of a probiotic in reversing abnormalities induced by early life stress and could be an alternative for brain health along the gut-brain axis.

Matched MeSH terms: Hot Temperature
Effect of temperature, oxygen and light on the degradation of β-carotene, lutein and α-tocopherol in spray-dried spinach juice powder during storage

Syamila M, Gedi MA, Briars R, Ayed C, Gray DA

Food Chem, 2019 Jun 30;284:188-197.
PMID: 30744845 DOI: 10.1016/j.foodchem.2019.01.055

The aim of this study was to evaluate the interaction between packaging parameters (transmission of light and oxygen) and storage temperatures (4, 20, 40 °C) on nutrient retention of Spinach (Spinacia oleracea) juice, spray-dried in the absence of an added encapsulant. β-Carotene was more susceptible to degradation compared with lutein and α-tocopherol. Under our experimental conditions, it was observed that excluding low fluorescent light intensity and air by vacuum packaging at 20 °C did not seem to improve nutrient retention loss over time (p > 0.05). The rate of β-carotene, lutein and α-tocopherol loss displayed first order reaction kinetic with low activation energy of 0.665, 2.650 and 13.893 kJ/mol for vacuum, and 1.089, 4.923 and 14.142 kJ/mol for non-vacuum, respectively. The reaction kinetics and half-life for β-carotene, lutein and α-tocopherol at 4 °C and non-vacuumed were 2.2 × 10-2, 1.2 × 10-2, and 0.8 × 10-2 day-1, and 32.08, 58.25 and 85.37 day, respectively.

Matched MeSH terms: Temperature
Fulltext Preparation and Evaluation Pumpkin Seed Oil-based Vitamin E Cream Formulations for Topical Application

Ong TS, Chu CC, Tan CP, Nyam KL

J Oleo Sci, 2020;69(4):297-306.
PMID: 32249259 DOI: 10.5650/jos.ess19250

Plant seed oil is often incorporated into the cream emulsions to provide multifunctional effects on the skin. In the current study, pumpkin seed oil (PSO) was used to develop a stable oil-in-water emulsion. The study aimed to optimise PSO cream formulation and determine the synergistic effect of the PSO with vitamin E oil added. The physical properties, antioxidant activities and storage stability of the formulations were analysed. Besides, the synergistic effect of the best formulation was analysed based on α-tocopherol content using ultra-high performance liquid chromatography (UHPLC). The storage stability test was assessed upon storing at 25 ± 2°C and 40 ± 2°C for 12 weeks. The best formulation (20% PSO, vitamin E oil and beeswax) selected showed physically and microbiologically stable. The incorporation of vitamin E oil into the formulation produced with PSO was found to be compatible, as it showed a synergistic effect in the amount of α-tocopherol content (combination index (CI) = 0.98). Thus, PSO had shown its potency to be incorporated into the topical products with a promising potential in delivering additional properties that can nourish the skin.

Matched MeSH terms: Temperature
Catalytic performance of Cu/ZnO/Al2O3/ZrO2 for slurry methanol synthesis from CO2 Hydrogenation: Effect of Cu/Zn Molar Ratio

Salina Shaharun, Maizatul S. Shaharun, Mohamad F.M. Shah, Nurul A. Amer

Sains Malaysiana, 2018;47:207-214.

Catalytic hydrogenation of carbon dioxide (CO2) to methanol is an attractive way to recycle and utilize CO2. A series of Cu/ZnO/Al2O3/ZrO2 catalysts (CZAZ) containing different molar ratios of Cu/Zn were prepared by the co-precipitation method. The catalysts were characterized by temperature-programmed reduction (TPR), field emission scanning electron microscopy-energy dispersive x-ray analysis (FESEM-EDX) and X-ray diffraction (XRD). Higher surface area, SABET values (42.6-59.9 m2/g) were recorded at low (1) and high (5) Cu/Zn ratios with the minimum value of 35.71 m2/g was found for a Cu/Zn of 3. The reducibility of the metal oxides formed after calcination of catalyst samples was also affected due to change in metal-support interaction. At a reaction temperature of 443 K, total gas pressure of 3.0 MPa and 0.1 g/mL of the CZAZ catalyst, the selectivity to methanol decreased as the Cu/Zn molar ratio increased, and the maximum selectivity of 93.9 was achieved at Cu/Zn molar ratio of 0.33. With a reaction time of 3h, the best performing catalyst was CZAZ75 with Cu/Zn molar ratio of 5 giving methanol yield of 6.4%.

Matched MeSH terms: Temperature
Improvement of indoor air quality using local fabricated activated carbon from date stones

Radaideh JA, Alazba AA, Amin MN, Shatnawi ZN, Amin MT

Sains Malaysiana, 2016;45:59-69.

Indoor air quality assessment in residential areas of Al-Hofuf city/Eastern region of Saudi Arabia is investigated through a multi-week multiple sites sampling survey. Critical air pollution indicators, including nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), carbon dioxide (CO2) and total volatile organic compounds (TVOC) as well as temperatures were measured and analyzed during the study period from January to May 2014. Three site-types - roadside, urban and rural - were selected and within each site type, six locations were selected to study the varying indoor/outdoor air quality. The results indicated that NO2 and CO concentrations increased at the starting hours of the day. SO2 concentrations were relatively low and constant. In addition, a strong association between outdoor and indoor air quality was found. Measurements showed that indoor/outdoor ratio for TVOC ranged from 0.8 to 0.99. For CO2, NO2 and SO2, this was 0.92-1.15, 0.5-0.7 and 0.52-0.9, respectively. Finally, the effects of activated carbon (AC) were investigated to assess the extent of the improvement in the indoor air quality. The analysis of data obtained indicated that using locally prepared AC from date stones was an effective way to reduce the indoor air pollution with an overall efficiency of 85.5, while the use of industrial granular AC reduced the air pollutants with an efficiency of less than 0.6. In addition, AC was exposed to an exhaust gas flow to evaluate its elimination potential for high concentrated pollutants. The obtained results demonstrated that AC was also functioning as an efficient absorbent with an overall removal efficiency of 77.8%, even when it was exposed to high concentrations.

Matched MeSH terms: Temperature

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