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Effect of salts addition on hydrogen production by C. acetobutylicum

Alshiyab H, Kalil MS, Hamid AA, Wan Yusoff WM

Pak J Biol Sci, 2008 Sep 15;11(18):2193-200.
PMID: 19137827

The objective of this study is to investigate the effect of salts addition to fermentation medium on hydrogen production, under anaerobic batch culture system. In this study, batch experiments were conducted to investigate the inhibitory effect of both NaCl and sodium acetate on hydrogen production. The optimum pH and temperature for hydrogen production were at initial pH of 7.0 and 30 degrees C. Enhanced production of hydrogen, using glucose as substrate was achieved. In the absence of Sodium Chloride and Sodium Acetate enhanced hydrogen yield (Y(P/S)) from 350 mL g(-1) glucose utilized to 391 mL g(-1) glucose utilized with maximum hydrogen productivity of 77.5 ml/L/h. Results also show that sodium chloride and sodium acetate in the medium adversely affect growth. Hydrogen yield per biomass (Y(P/X)) of 254 ml/L/g, biomass per substrate utilized (Y(X/S)) of 0.268 and (Y(H2/S) of 0.0349. The results suggested that Sodium at any concentration resulted to inhibit the bacterial productivity of hydrogen.

Matched MeSH terms: Sodium Chloride/pharmacology
Eliminating iodine deficiency in rural Sarawak, Malaysia: the relevance of water iodization

Foo LC, Mahmud N, Satgunasingam N

Am J Public Health, 1998 Apr;88(4):680-1.
PMID: 9551019
Matched MeSH terms: Sodium Chloride, Dietary*
Fulltext Iodized salt supplementation and its effects on thyroid status amongst Orang Asli in Hulu Selangor, Malaysia

Lim KK, Wong M, Mohamud WN, Kamaruddin NA

Asia Pac J Clin Nutr, 2013;22(1):41-7.
PMID: 23353609 DOI: 10.6133/apjcn.2013.22.1.02

BACKGROUND: This research was performed to determine the prevalence of iodine deficiency disorder (IDD) and the effects of iodized salt supplementation on thyroid status amongst Orang Asli in Hulu Selangor, Malaysia.
METHODS: Study respondents were from three target groups, i.e. pre-school children (PSC), primary school-going children (SGC) and adult women. Each household was supplied with iodized salt fortified with iodate fortificant for a period of 12 months and the iodine levels in the salt ranged from 20 to 30 μg/L. Samples collected before and after 6 and 12 months of introduction to iodized salt were urine from all groups, as well as serum samples from adult women.
RESULTS: A total of 200 respondents were recruited; 58 (29.0%) PSC, 65 (32.5%) SGC and 77 (38.5%) adult women. The median urine-iodine concentration (mUIC) in all groups were of moderately low before the iodized salt intervention, but increased significantly in all study groups after 6 and 12 months of intervention. However, at the end of the study, there was an increase in severe iodine deficiency (mUIC <20 μg/L) from 7.5% to 12% and about 9% of PSC and SGC respondents had mUIC level of more than 300 μg/L while the adult women showed a significant increase in free triiodothyronine (fT3) levels.
CONCLUSION: The study demonstrated that iodized salt supplementation was able to show an improvement in iodine level amongst Orang Asli. However, an increase in severe iodine deficiency and iodine excess indicated that the iodized salt programme needs to be carefully monitored.

Matched MeSH terms: Sodium Chloride, Dietary/administration & dosage*; Sodium Chloride, Dietary/urine
Effects of washing pre-treatment on mercury concentration in fish tissue

Hajeb P, Jinap S

Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2009 Oct;26(10):1354-61.
PMID: 19690999 DOI: 10.1080/02652030903150567

The objective of this study was to examine the effect of washing pre-treatment on mercury concentration in fish fillet. Response surface methodology was used to investigate the influence of three variables, pH (1-6.5), NaCl (0-1% w/v) and exposure time (5-30 min) by using a three-factor central composite design. The aim was to obtain the best possible combination of these variables in order to reduce mercury in fish fillet. The experimental data were adequately fitted into a second-order polynomial model with multiple regression coefficients (R(2)) of 0.961. The results indicated that the reduction of mercury in fish flesh significantly depends on the pH of the solution used. The overall optimal condition resulting in the maximum mercury reduction in fish fillet was obtained at a combined level pH of 2.79, NaCl of 0.5% and exposure time of 13.5 min. The optimized protocol produced a solution that can reduce mercury from raw fish fillet up to 81%.

Matched MeSH terms: Sodium Chloride
Fulltext Loktanella spp. Gb03 as an algicidal bacterium, isolated from the culture of Dinoflagellate Gambierdiscus belizeanus

Bloh AH, Usup G, Ahmad A

Vet World, 2016 Feb;9(2):142-6.
PMID: 27051199 DOI: 10.14202/vetworld.2016.142-146

AIM: Bacteria associated with harmful algal blooms can play a crucial role in regulating algal blooms in the environment. This study aimed at isolating and identifying algicidal bacteria in Dinoflagellate culture and to determine the optimum growth requirement of the algicidal bacteria, Loktanella sp. Gb-03.
MATERIALS AND METHODS: The Dinoflagellate culture used in this study was supplied by Professor Gires Usup's Laboratory, School of Environmental and Natural Resources Sciences, Faculty of Science and Technology, University Kebangsaan Malaysia, Malaysia. The culture was used for the isolation of Loktanella sp., using biochemical tests, API 20 ONE kits. The fatty acid content of the isolates and the algicidal activity were further evaluated, and the phenotype was determined through the phylogenetic tree.
RESULTS: Gram-negative, non-motile, non-spore-forming, short rod-shaped, aerobic bacteria (Gb01, Gb02, Gb03, Gb04, Gb05, and Gb06) were isolated from the Dinoflagellate culture. The colonies were pink in color, convex with a smooth surface and entire edge. The optimum growth temperature for the Loktanella sp. Gb03 isolate was determined to be 30°C, in 1% of NaCl and pH7. Phylogenetic analysis based on 16S rRNA gene sequences showed that the bacterium belonged to the genus Loktanella of the class Alphaproteobacteria and formed a tight cluster with the type strain of Loktanella pyoseonensis (97.0% sequence similarity).
CONCLUSION: On the basis of phenotypic, phylogenetic data and genetic distinctiveness, strain Gb-03, were placed in the genus Loktanella as the type strain of species. Moreover, it has algicidal activity against seven toxic Dinoflagellate. The algicidal property of the isolated Loktanella is vital, especially where biological control is needed to mitigate algal bloom or targeted Dinoflagellates.

Matched MeSH terms: Sodium Chloride
Fulltext Ultraviolet-visible study on acid-base equilibria of aporphine alkaloids with antiplasmodial and antioxidant activities from Alseodaphne corneri and Dehaasia longipedicellata

Zahari A, Ablat A, Omer N, Nafiah MA, Sivasothy Y, Mohamad J, et al.

Sci Rep, 2016;6:21517.
PMID: 26898753 DOI: 10.1038/srep21517

The UV-vis spectra of isocorydine 1, norisocorydine 2 and boldine 3 were studied in 2% v/v acetonitrile, at constant ionic strength (0.1 M NaCl, 35 degree Celsius). The pK(a) values of isocorydine 1 and norisocorydine 2 were 11.75 and 12.07, respectively. Boldine 3 gave a pK(a) value of 9.16 and 10.44. All of the alkaloids 1-3 were stable at physiological pH; thereby all of them will not ionize, thus permitting the basic nitrogen to be protonated and accumulated within the acidic food vacuole of Plasmodium via pH trapping. Subsequently, acidic food vacuoles that have been neutralized by alkaloids would result in enhancement of the antiplasmodial activity. The alkaloids showed antiplasmodial activity against Plasmodium falciparum and antioxidant activities; DPPH radical scavenging, metal chelating and ferric reducing power. The antioxidant properties of the alkaloids under investigation revealed that in addition to the antiplasmodial activity, the alkaloids can also prevent oxidative damage. It can be prevented by binding free heme and neutralizing the electrons produced during the Plasmodium falciparum mediated haemoglobin destruction in the host. Slightly basic properties of the aforementioned alkaloids, along with their antioxidant activities, are advantageous in improving the suppression of malaria infection that cause less damage to the host.

Matched MeSH terms: Sodium Chloride
Simultaneous analysis of silicon and boron dissolved in water by combination of electrodialytic salt removal and ion-exclusion chromatography with corona charged aerosol detection

Mori M, Sagara K, Arai K, Nakatani N, Ohira S, Toda K, et al.

J Chromatogr A, 2016 Jan 29;1431:131-7.
PMID: 26755416 DOI: 10.1016/j.chroma.2015.12.064

Selective separation and sensitive detection of dissolved silicon and boron (DSi and DB) in aqueous solution was achieved by combining an electrodialytic ion isolation device (EID) as a salt remover, an ion-exclusion chromatography (IEC) column, and a corona charged aerosol detector (CCAD) in sequence. DSi and DB were separated by IEC on the H(+)-form of a cation exchange resin column using pure water eluent. DSi and DB were detected after IEC separation by the CCAD with much greater sensitivity than by conductimetric detection. The five-channel EID, which consisted of anion and cation acceptors, cathode and anode isolators, and a sample channel, removed salt from the sample prior to the IEC-CCAD. DSi and DB were scarcely attracted to the anion accepter in the EID and passed almost quantitatively through the sample channel. Thus, the coupled EID-IEC-CCAD device can isolate DSi and DB from artificial seawater and hot spring water by efficiently removing high concentrations of Cl(-) and SO4(2-) (e.g., 98% and 80% at 0.10molL(-1) each, respectively). The detection limits at a signal-to-noise ratio of 3 were 0.52μmolL(-1) for DSi and 7.1μmolL(-1) for DB. The relative standard deviations (RSD, n=5) of peak areas were 0.12% for DSi and 4.3% for DB.

Matched MeSH terms: Sodium Chloride
Fulltext The prevalence of endemic goitre among Penans of the Baram

Chen PC, Yap SB

Med J Malaysia, 1988 Jun;43(2):159-61.
PMID: 3266288
Matched MeSH terms: Sodium Chloride
Fulltext Endemic goitre: a preventable and yet highly prevalent disease in Sarawak (letter)

Tan YK

Med J Malaysia, 1982 Mar;37(1):96-7.
PMID: 7121358

Comment on: Chen PC. Endemic goitre: a preventable and yet highly prevalent disease in
Sarawak. Med J Malaysia. 1981 Jun;36(2):67-9

Matched MeSH terms: Sodium Chloride
Fulltext Role of Phase-Dependent Dielectric Properties of Alumina Nanoparticles in Electromagnetic-Assisted Enhanced Oil Recovery

Adil M, Lee KC, Zaid HM, Manaka T

Nanomaterials (Basel), 2020 Oct 06;10(10).
PMID: 33036153 DOI: 10.3390/nano10101975

The utilization of metal-oxide nanoparticles in enhanced oil recovery (EOR) has generated considerable research interest to increase the oil recovery. Among these nanoparticles, alumina nanoparticles (Al2O3-NPs) have proved promising in improving the oil recovery mechanism due to their prominent thermal properties. However, more significantly, these nanoparticles, coupled with electromagnetic (EM) waves, can be polarized to reduce water/oil mobility ratio and create disturbances at the oil/nanofluid interface, so that oil can be released from the reservoir rock surfaces and travelled easily to the production well. Moreover, alumina exists in various transition phases (γ, δ, θ, κ, β, η, χ), providing not only different sizes and morphologies but phase-dependent dielectric behavior at the applied EM frequencies. In this research, the oil recovery mechanism under EM fields of varying frequencies was investigated, which involved parameters such as mobility ratio, interfacial tension (IFT) and wettability. The displacement tests were conducted in water-wet sandpacks at 95 °C, by employing crude oil from Tapis. Alumina nanofluids (Al2O3-NFs) of four different phases (α, κ, θ and γ) and particle sizes (25-94.3 nm) were prepared by dispersing 0.01 wt. % NPs in brine (3 wt. % NaCl) together with SDBS as a dispersant. Three sequential injection scenarios were performed in each flooding scheme: (i) preflushes brine as a secondary flooding, (ii) conventional nano/EM-assisted nanofluid flooding, and (iii) postflushes brine to flush NPs. Compared to conventional nanofluid flooding (3.03-11.46% original oil in place/OOIP) as incremental oil recovery, EM-assisted nanofluid flooding provided an increase in oil recovery by approximately 4.12-12.90% of OOIP for different phases of alumina. It was established from these results that the recovery from EM-assisted nanofluid flooding is itself dependent on frequency, which is associated with good dielectric behavior of NPs to formulate the oil recovery mechanism including (i) mobility ratio improvement due to an electrorheological (ER) effect, (ii) interfacial disturbances by the oil droplet deformation, and (iii) wettability alteration by increased surface-free energy.

Matched MeSH terms: Sodium Chloride
A novel wound healing accelerator: Effect of vitreous gel of cow eyeball on a chronic wound model

Makhmudi A, Wirohadidjojo YW, Gahara E, Noor HZ, Sunardi M, Mahmudah NA, et al.

Med J Malaysia, 2020 11;75(6):698-704.
PMID: 33219180

INTRODUCTION: Several studies have reported the disturbance in the process of wound healing after administration of mitomycin-C, which inhibits granulation tissue formation and collagen synthesis, resulting in chronic wounds. The vitreous gel of cow eyeballs contains a high level of hyaluronic acid, which has a role in inflammation, granulation, re-epithelialization, and remodelling. This study aims to understand the effect of 1% povidone iodine and vitreous gel of cow eyeballs on wound healing after administration of mitomycin-C.
METHODS: This was an in vivo study with quasi-experimental methods on 32 Wistar mice. Full-thickness wounds were made and then treated with mitomicyn-C. The mice were divided into 4 groups: a control group with NaCl 0.9% vitreous gel of cow eyeball (VGCE), 1% povidone-iodine, and a combination of VGCE and 1% povidone-iodine groups. Macroscopic and microscopic observations of the process of wound healing were performed on days 3, 7, and 14.
RESULTS: Vitreous gel administration produced significant wound healing rates within the first three days, and histological analysis revealed an increased number of fibroblasts and polymorphonuclear cells. However, the povidone iodine group and the combination group with vitreous gel did not produce significant results.
CONCLUSION: The single administration of VGCE can accelerate the wound healing process, increase the number of fibroblasts, and reduce inflammation in a chronic wound model.

Matched MeSH terms: Sodium Chloride
Fulltext Salting-out assisted liquid-liquid extraction coupled with high-performance liquid chromatography for the determination of vitamin D3 in milk samples

Sazali NH, Alshishani A, Saad B, Chew KY, Chong MM, Miskam M

R Soc Open Sci, 2019 Aug;6(8):190952.
PMID: 31598260 DOI: 10.1098/rsos.190952

In this study, salting-out assisted liquid-liquid extraction (SALLE) as a simple and efficient extraction technique followed by high-performance liquid chromatography (HPLC) was employed for the determination of vitamin D3 in milk samples. The sample treatment is based on the use of water-miscible acetonitrile as the extractant and acetonitrile phase separation under high-salt conditions. Under the optimum conditions, acetonitrile and ammonium sulfate were used as the extraction solvent and salting-out agent, respectively. The vitamin D3 extract was separated using Hypersil ODS (250x i.d 4.6 mm, 5 µm) HPLC column that was coupled with diode array detector. Vitamin D2 was used as internal standard (IS) to offset any variations in chromatographic conditions. The vitamin D3 and the IS were eluted in 18 min. Good linearity (r2 > 0.99) was obtained within the range of 25-600 ng g-1 with the limit of detection of 15 ng g-1 and limit of quantification of 25 ng g-1. The validated method was applied for the determination of vitamin D3 in milk samples. The recoveries for spiked samples were from 94.4 to 113.5%.

Matched MeSH terms: Sodium Chloride
Haloadaptation: insights from comparative modeling studies between halotolerant and non-halotolerant dehalogenases

Edbeib MF, Aksoy HM, Kaya Y, Wahab RA, Huyop F

J Biomol Struct Dyn, 2020 Aug;38(12):3452-3461.
PMID: 31422756 DOI: 10.1080/07391102.2019.1657498

Halophiles are extremophilic microorganisms that grow optimally at high salt concentrations by producing a myriad of equally halotolerant enzymes. Structural haloadaptation of these enzymes adept to thriving under high-salt environments, though are not fully understood. Herein, the study attempts an in silico investigation to identify and comprehend the evolutionary structural adaptation of a halotolerant dehalogenase, DehHX (GenBank accession number: KR297065) of the halotolerant Pseudomonas halophila, over its non-halotolerant counterpart, DehMX1 (GenBank accession number KY129692) produced by Pseudomonas aeruginosa. GC content of the halotolerant DehHX DNA sequence was distinctively higher (58.9%) than the non-halotolerant dehalogenases (55% average GC). Its acidic residues, Asp and Glu were 8.27% and 12.06%, respectively, compared to an average 5.5% Asp and 7% Glu, in the latter; but lower contents of basic and hydrophobic residues in the DehHX. The secondary structure of DehHX interestingly revealed a lower incidence of α-helix forming regions (29%) and a higher percentage of coils (57%), compared to 49% and 29% in the non-halotolerant homologues, respectively. Simulation models showed the DehHX is stable under a highly saline environment (25% w/v) by adopting a highly negative-charged surface with a concomitant weakly interacting hydrophobic core. The study thus, established that a halotolerant dehalogenase undergoes notable evolutionary structural changes related to GC content over its non-halotolerant counterpart, in order to adapt and thrive under highly saline environments.Communicated by Ramaswamy H. Sarma.

Matched MeSH terms: Sodium Chloride
Biosynthesis of butyl esters from crude oil of palm fruit and kernel using halophilic lipase secretion by Marinobacter litoralis SW-45

Musa H, Kasim FH, Gunny AAN, Gopinath SCB, Ahmad MA

3 Biotech, 2019 Aug;9(8):314.
PMID: 31406636 DOI: 10.1007/s13205-019-1845-y

Initially, a new moderate halophilic strain was locally isolated from seawater. The partial 16S rRNA sequence analysis positioned the organism in Marinobacter genus and was named 'Marinobacter litoralis SW-45'. This study further demonstrates successful utilization of the halophilic M. litoralis SW-45 lipase (MLL) for butyl ester synthesis from crude palm fruit oil (CPO) and kernel oil (CPKO) in heptane and solvent-free system, respectively, using hydroesterification. Hydrolysis and esterification of enzymatic [Thermomyces lanuginosus lipase (TLL)] hydrolysis of CPO and CPKO to free fatty acids (FFA) followed by MLL-catalytic esterification of the concentrated FFAs with butanol (acyl acceptor) to synthesize butyl esters were performed. A one-factor-at-a-time technique (OFAT) was used to study the influence of physicochemical factors on the esterification reaction. Under optimal esterification conditions of 40 and 45 °C, 150 and 230 rpm, 50% (v/v) biocatalyst concentration, 1:1 and 5:1 butanol:FFA, 9% and 15% (w/v) NaCl, 60 and 15 min reaction time for CPO- and CPKO-derived FFA esterification system, maximum ester conversion of 62.2% and 69.1%, respectively, was attained. Gas chromatography (GC) analysis confirmed the products formed as butyl esters. These results showed halophilic lipase has promising potential to be used for biosynthesis of butyl esters in oleochemical industry.

Matched MeSH terms: Sodium Chloride
Fulltext High-quality RNA isolation from pigment-rich Dendrobium flowers

Khairul-Anuar MA, Mazumdar P, Lau SE, Tan TT, Harikrishna JA

3 Biotech, 2019 Oct;9(10):371.
PMID: 31588395 DOI: 10.1007/s13205-019-1898-y

Isolation of high-quality RNA from Dendrobium flowers is challenging because of the high levels of pigment, polysaccharides, and polyphenols. In the present study, an efficient CTAB method for RNA extraction from the pigment-rich flowers of Dendrobium was optimised. The optimised method yielded high quantities of RNA (10.1-12.9 µg/g). Spectrophotometric values of A260/280 in the range of 2.2 to 2.4 and A260/230 values of 2.0 suggested that the isolated RNA was free of polyphenols, polysaccharides, and protein contaminants. RNA integrity numbers determined by microfluidics were in the range of 7.9-8.9 indicative of intact RNA. In the improved method, the addition of 3 M NaCl and 3% PVP-10 in the extraction buffer, followed by an incubation period of 45 min at 65 °C, eliminated most of the polysaccharides, polyphenolic compounds, and denatured protein. Extraction with phenol:chloroform:isoamyl alcohol (125:24:1) effectively removed pigments from the aqueous phase, while the precipitation of RNA with lithium chloride minimised the co-precipitation of protein, DNA, and polysaccharide and resulted in the extraction of high quality of RNA. The suitability of the RNA for downstream processing was confirmed via RT-PCR amplification of Chalcone synthase gene from cDNA prepared from RNA isolated from different developmental stages of the flower of a Dendrobium hybrid. The present method will be highly useful for the isolation of RNA from pigment, polyphenol, and polysaccharide-rich plant tissues.

Matched MeSH terms: Sodium Chloride
Fulltext Safety and quality preservation of starfruit (Averrhoa carambola) at ambient shelf life using synergistic pectin-maltodextrin-sodium chloride edible coating

Mohd Suhaimi NI, Mat Ropi AA, Shaharuddin S

Heliyon, 2021 Feb;7(2):e06279.
PMID: 33681497 DOI: 10.1016/j.heliyon.2021.e06279

The demand for fresh, safe, and healthy fruits by consumers has increased, which concurrently occurs with an increase in initiatives on reducing food wastage. Starfruit consists of good nutrition and valuable sensory attributes, but its shelf life is short and can only be preseved for a few days at ambient storage. This research was conducted to determine the effectiveness of synergistic edible coatings (pectin [Pe] and maltodextrin [M] and 100, 200, and 300 ppm of sodium chloride [SC]) on the quality and safety criterion of starfruits throughout a shelf life analysis of 14 days at ambient temperature. Consumer acceptability of the edible-coated starfruit was also evaluated. The coating process was performed using a dipping method. The uncoated (control) and coated samples were evaluated for the characteristics of weight, pH, total soluble solids (TSS), water activity, color, texture, microbial growth, FTIR, and sensory evaluation. From the results, the starfruit coated with Pe + M + 100 ppm SC had a significantly lower weight-loss trend compared to the other samples. On day 14, pH of the coated starfruits were 3.02, 3.14, and 3.31 for 100, 200, and 300 ppm of SC, respectively, were found to be significantly different (p < 0.05) from the control (pH 3.49). The control had a significantly higher value of total soluble solids (6.00 ⁰Brix) compared to the coated starfruits (6.00, 5.47, and 5.33 ⁰Brix, respectively). The coated samples have significantly higher values of firmness than control especially in initial days of storage. It was observed that Pe + M + 100 ppm SC could minimize the spoilage of fruits by reducing the growth of yeast and mold, as well as bacteria, up to 0.86 and 2.02 log CFU/ml, respectively. FTIR results confirmed the presence of the coating on the starfruit. In the sensory evaluation, no significance different (p > 0.05) were obtained for all the sensory attributes and overall acceptability for day 0 and 3. In conclusion, starfruit coated with synergistic Pe + M + 100 ppm SC appeared to be the best sample in extending its shelf life and maintaining the physicochemical characteristics of starfruits up to more than 14 days.

Matched MeSH terms: Sodium Chloride
Fulltext Surface Modification of Polytetrafluoroethylene Hollow Fiber Membrane for Direct Contact Membrane Distillation through Low-Density Polyethylene Solution Coating

Mohd Ramli MR, Ahmad AL, Leo CP

ACS Omega, 2021 Feb 23;6(7):4609-4618.
PMID: 33644568 DOI: 10.1021/acsomega.0c05107

Membrane distillation (MD) is an attractive technology for the separation of highly saline water used with a polytetrafluoroethylene (PTFE) hollow fiber (HF) membrane. A hydrophobic coating of low-density polyethylene (LDPE) coats the outer surface of the PTFE membrane to resolve membrane wetting as well as increase membrane permeability flux and salt rejection, a critical problem regarding the MD process. LDPE concentrations in coating solution have been studied and optimized. Consequently, the LDPE layer altered membrane morphology by forming a fine nanostructure on the membrane surface that created a hydrophobic layer, a high roughness of membrane, and a uniform LDPE network. The membrane coated with different concentrations of LDPE exhibited high water contact angles of 135.14 ± 0.24 and 138.08 ± 0.01° for membranes M-3 and M-4, respectively, compared to the pristine membrane. In addition, the liquid entry pressure values of LDPE-incorporated PTFE HF membranes (M-1 to M-5) were higher than that of the uncoated membrane (M-0) with a small decrease in the percentage of porosity. The M-3 and M-4 membranes demonstrated higher flux values of 4.12 and 3.3 L m-2 h-1 at 70 °C, respectively. On the other hand, the water permeation flux of 1.95 L m-2 h-1 for M-5 further decreased when LDPE concentration is increased.

Matched MeSH terms: Sodium Chloride
Fulltext Effect of Aging, Antioxidant, and Mono- and Divalent Ions at High Temperature on the Rheology of New Polyacrylamide-Based Co-Polymers

Akbari S, Mahmood SM, Tan IM, Ling OL, Ghaedi H

Polymers (Basel), 2017 Oct 04;9(10).
PMID: 30965788 DOI: 10.3390/polym9100480

The viscosity of four new polymers was investigated for the effect of aging at high temperature, with varying degrees of salinity and hardness. The four sulfonated based polyacrylamide co-polymers were FLOCOMB C7035; AN132 VHM; SUPERPUSHER SAV55; and THERMOASSOCIATIF copolymers. All polymer samples were aged at 80 °C for varying times (from zero to at least 90 days) with and without isobutyl alcohol (IBA) as an antioxidant. To see the effect of divalent ions on the polymer solution viscosity, parallel experiments were performed in a mixture of CaCl₂-NaCl of the same ionic strength as 5 wt % NaCl. The polymers without IBA showed severe viscosity reduction after aging for 90 days in both types of preparation (5 wt % NaCl or CaCl₂-NaCl). In the presence of IBA, viscosity was increased when aging time was increased for 5 wt % NaCl. In CaCl₂-NaCl, on the other hand, a viscosity reduction was observed as aging time was increased. This behavior was observed for all polymers except AN132 VHM.

Matched MeSH terms: Sodium Chloride
Fulltext Assessment of Polyacrylamide Based Co-Polymers Enhanced by Functional Group Modifications with Regards to Salinity and Hardness

Akbari S, Mahmood SM, Tan IM, Ghaedi H, Ling OL

Polymers (Basel), 2017 Nov 27;9(12).
PMID: 30965947 DOI: 10.3390/polym9120647

This research aims to test four new polymers for their stability under high salinity/high hardness conditions for their possible use in polymer flooding to improve oil recovery from hydrocarbon reservoirs. The four sulfonated based polyacrylamide co-polymers were FLOCOMB C7035; SUPERPUSHER SAV55; THERMOASSOCIATIF; and AN132 VHM which are basically sulfonated polyacrylamide copolymers of AM (acrylamide) with AMPS (2-Acrylamido-2-Methylpropane Sulfonate). AN132 VHM has a molecular weight of 9⁻11 million Daltons with 32 mol % degree of sulfonation. SUPERPUSHER SAV55 mainly has about 35 mol % sulfonation degree and a molecular weight of 9⁻11 million Daltons. FLOCOMB C7035, in addition, has undergone post-hydrolysis step to increase polydispersity and molecular weight above 18 million Daltons but it has a sulfonation degree much lower than 32 mol %. THERMOASSOCIATIF has a molecular weight lower than 12 million Daltons and a medium sulfonation degree of around 32 mol %, and also contains LCST (lower critical solution temperature) type block, which is responsible for its thermoassociative characteristics. This paper discusses the rheological behavior of these polymers in aqueous solutions (100⁻4500 ppm) with NaCl (0.1⁻10 wt %) measured at 25 °C. The effect of hardness was investigated by preparing a CaCl₂-NaCl solution of same ionic strength as the 5 wt % of NaCl. In summary, it can be concluded that the rheological behavior of the newly modified co-polymers was in general agreement to the existing polymers, except that THERMOASSOCIATIF polymers showed unique behavior, which could possibly make them a better candidate for enhanced oil recovery (EOR) application in high salinity conditions. The other three polymers, on the other hand, are better candidates for EOR applications in reservoirs containing high divalent ions. These results are expected to be helpful in selecting and screening the polymers for an EOR application.

Matched MeSH terms: Sodium Chloride
First Report of Soft Rot Caused by Pectobacterium carotovorum subsp. carotovorum on Cucumber in Malaysia

Nazerian E, Sijam K, Zainal Abidin MA, Vadamalai G

Plant Dis, 2011 Nov;95(11):1474.
PMID: 30731752 DOI: 10.1094/PDIS-10-10-0754

Cucumber (Cucumis sativus L.) is one of the most important vegetable fruits in Malaysia. Cucumber is principally grown in the states of Johor, Kelantan, and Perak. The broad host range Enterobacteriaceae pathogen, Pectobacterium carotovorum, can cause soft rot on stems or cucumber fruit. In Malaysia, cucumber is produced in a warm, humid climate, thus the plant is susceptible to attack by P. carotovorum at any time during production. In 2010, cucumber samples with wilted and chlorotic leaves, water-soaked lesions, and collapsed fruits were found in multiple fields. Small pieces of infected stems and fruit were immersed in 5 ml of saline solution (0.85% NaCl) for 20 min and then 50 μl of this suspension was spread onto nutrient agar (NA) and incubated at 27°C for 24 h. White-to-pale gray colonies with irregular margins were selected for analysis. For pathogenicity tests, cucumber fruits were surface sterilized by ethyl alcohol 70%, washed with sterilized distilled water, cut into small pieces, and inoculated with 20 μl of 108 CFU/ml suspensions of five representative strains. Cucumber plants were grown for 3 weeks in sterilized soil and their stems were inoculated with 20 μl of 108 CFU/ml of bacterial suspension. Inoculated samples and control (noninoculated) plants were placed in a growth chamber with 80 to 90% relative humidity at 27°C. Symptoms occurred on fruit slices and stems after 1 to 3 days and appeared the same as naturally infected samples, but the control samples remained healthy. Koch's postulates were fulfilled with the reisolation of cultures with the same characteristics as described earlier. Hypersensitivity reaction (HR) assays were done by infiltrating 108 CFU/ml of bacterial suspension into tobacco leaf epidermis and HR developed. All strains were subjected to biochemical and morphological assays, as well as molecular assessment. The strains were gram negative, facultative anaerobes, rod shaped, able to macerate potato slices and growth at 37°C; catalase positive; oxidase and phosphatase negative; able to degrade pectate; sensitive to erythromycin; negative for utilization of α-methyl glycoside, indole production, and reduction of sugars from sucrose; acid production from arabitol, sorbitol, and utilization of citrate were negative, but positive for raffinose and melibiose utilization. PCR amplification of the pel gene by Y1 and Y2 primers produced a 434-bp fragment on agarose gel 1% (1). Amplification of intergenic transcribed spacer region by G1 and L1 primers gave two main bands at approximately 535 and 580 bp on agarose gel 1.5%. The ITS-PCR products were digested with RsaI restriction enzyme (3). On the basis of biochemical and morphological characteristics, PCR-based pel gene and characterization of the ITS region, and digestion of the ITS-PCR products with RsaI restriction enzyme, all isolates were identified as P. carotovorum subsp. carotovorum. To our knowledge, this is the first report of soft rot caused by P. carotovorum subsp. carotovorum on cucumber from Malaysia. References: (1) A. Darraas et al. Appl. Environ. Microbiol. 60:1437, 1994. (2) N. W Schaad et al. Laboratory Guide for the Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society Press, St. Paul, 2001. (3) I. K. Toth et al. Appl. Environ. Microbiol. 67:4070, 2001.

Matched MeSH terms: Sodium Chloride

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