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Fulltext Allergens derived from shrimp

Mary Margaret, P.D.S., Jinap, S., Ahmad Faizal, A.R.

International Food Research Journal, 2015;22(5):1751-1754.
MyJurnal

Allergy caused by food is usually type 1 allergy of four types of allergic reactions. One of the most widespread allergic is those that are caused by crustacean shellfish. Crustaceans are classified among arthropods which include crab, crayfish, lobster, prawn and shrimp. Shrimp which are broadly consumed as nutritional food is one of the most important food that contribute to allergy. Thus, reducing the allergenicity of shrimp allergen will be helpful to individuals who are sensitive to shrimp and for this reason the characteristics of each allergen need to be studied. Those sensitized individuals can develop urticaria, angiodema, laryngospasm, asthma and life threatening anaphylaxis. To date, four main allergens contribute to allergic reactions. They are tropomyosin (TM), a highly conserved and heat stable myofibrillar protein of 35-38 kDa followed by arginine kinase (AK) which is also known as Pen m 2 or Lit v 2 with 40 kDa. Two other contributing allergens are sarcoplasmic calcium-binding protein (SCP) also known as Lit v 4 with 22 kDa and myosin light chain (MLC) which is also termed as Lit v 3 with 20 kDa. This mini-review will provide a better understanding of each allergen derived from shrimp which subsequently will help to reduce the allergenicity.

Matched MeSH terms: Hot Temperature
Investigation of Requisites for the Optimal Mycelial Growth of the Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), on Oil Palm Biomass in Malaysia

Sudheer S, Ali A, Manickam S

Int J Med Mushrooms, 2016;18(10):935-943.
PMID: 27910761

Rigorous research has been carried out regarding the cultivation of Ganoderma lucidum using different agricultural residues. Nevertheless, large-scale cultivation and the separation of active compounds of G. lucidum are still challenges for local farmers. The objective of this study was to evaluate the use of oil palm waste fibers such as empty fruit bunch fibers and mesocarp fibers as effective substrates for the growth of G. lucidum mycelia to study the possibility of solid-state cultivation and to determine the optimum conditions necessary for the growth of mycelia of this mushroom on these waste fibers. Various parameters such as temperature, pH, humidity, and carbon and nitrogen compositions required for the optimum growth of mycelia have been determined. Oil palm fibers are a vivid source of lignocellulose, and their availability in Malaysia is high compared to that of sawdust. G. lucidum is a wood-rotting fungi that can easily decay and utilize this lignocellulose biomass, a major agricultural waste in Malaysia.

Matched MeSH terms: Temperature
Enzyme-Mimic Peptide Assembly To Achieve Amidolytic Activity

Wong YM, Masunaga H, Chuah JA, Sudesh K, Numata K

Biomacromolecules, 2016 Oct 10;17(10):3375-3385.
PMID: 27642764

Amyloid fibers are classified as a new generation of tunable bionanomaterials that exhibit new functions related to their distinctive characteristics, such as their universality, tunability, and stiffness. Here, we introduce the catalytic residues of serine protease into a peptide catalyst (PC) via an enzyme-mimic approach. The rational design of a repeating pattern of polar and nonpolar amino acids favors the conversion of the peptides into amyloid-like fibrils via self-assembly. Distinct fibrous morphologies have been observed at different pH values and temperatures, which indicates that different fibril packing schemes can be designed; hence, fibrillar peptides can be used to generate efficient artificial catalysts for amidolytic activities at mild pH values. The results of atomic force microscopy, Raman spectroscopy, and wide-angle X-ray scattering analyses are used to discuss and compare the fibril structure of a fibrillar PC with its amidolytic activity. The pH of the fibrillation reaction crucially affects the pKa of the side chains of the catalytic triads and is important for stable fibril formation. Temperature is another important parameter that controls the self-assembly of peptides into highly stacked and laminated morphologies. The morphology and stability of fibrils are crucial and represent important factors for demonstrating the capability of the peptides to exert amidolytic activity. The observed amidolytic activity of PC4, one of the PCs, was validated using an inhibition assay, which revealed that PC4 can perform enzyme-like amidolytic catalysis. These results provide insights into the potential use of designed peptides in the generation of efficient artificial enzymes.

Matched MeSH terms: Temperature
Fulltext Engineering characterisation of epoxidized natural rubber-modified hot-mix asphalt

Al-Mansob RA, Ismail A, Yusoff NI, Rahmat RA, Borhan MN, Albrka SI, et al.

PLoS One, 2017;12(2):e0171648.
PMID: 28182724 DOI: 10.1371/journal.pone.0171648

Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR-asphalt mixes prepared using the wet process. Mechanical testing on the ENR-asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR-asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR-asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress.

Matched MeSH terms: Hot Temperature
Fulltext Sulfated galactans from red seaweeds and their potential applications

Lim, Yi-Yi, Lee, Wei-Kang, Leow, Adam Thean-Chor, Parameswari Namasivayam, Janna-Ong Abdullah, Ho, Chai-Ling

The Pertanika Journal of Scholarly Research Reviews, 2018;4(2):1-17.
MyJurnal

Red seaweeds (Rhodophyta) produce a variety of sulfated galactans in their cell wall matrix and intercellular space, contributing up to 50-60 % of their total dry weight. These sulfated polysaccharides are made up of galactose disaccharides substituted with sulfate, methoxyl, pyruvic acid, or non-galactose monosaccharides (e.g. xylose, glucose and mannose). They are required by the Rhodophytes for protection against pathogen, desiccation, tidal waves and extreme changes in pH, temperature and salinity. Since ancient times, sulfated galactans from red seaweeds, such as agar and carrageenan, have been consumed as human foods and later being used in traditional medicine. Nowadays, some red seaweeds are cultivated and exploited for commercial uses in various fields. In this review, different types of sulfated galactans found in red seaweeds and their current and potential uses in food, biotechnology, medical and pharmaceutical industries are discussed.

Matched MeSH terms: Temperature
Application of antimicrobial active packaging film made of semolina flour, nano zinc oxide and nano-kaolin to maintain the quality of low-moisture mozzarella cheese during low-temperature storage

Jafarzadeh S, Rhim JW, Alias AK, Ariffin F, Mahmud S

J Sci Food Agric, 2019 Apr;99(6):2716-2725.
PMID: 30350410 DOI: 10.1002/jsfa.9439

BACKGROUND: Active food packaging films with improved properties and strong antimicrobial activity were prepared by blending mixed nanomaterials with different ratio [1:4 (40 mg:160 mg), 3:2 (120 mg: 80 mg), 0:5 (0 mg: 200 mg) and 5:0 (200 mg:0 mg)] of ZnO and kaolin with semolina using a solvent casting method and used for the packaging of low moisture mozzarella cheese to test the effect of packaging on the quality change of the cheese for long-term (up to 72 days) refrigerated storage.
RESULTS: Compared with the neat semolina film, mechanical strength (TS) of the nanocomposite films increased significantly (increase in 21-65%) and water vapor barrier (WVP) and O2 gas barrier (OP) properties decreased significantly (decrease in 43-50% and 60-65%, respectively) depending on the blending ratio of ZnO and kaolin nanoclay. The nanocomposite films also exhibited strong antimicrobial activity against bacteria (E. coli and S. aureus), yeast (C. albicans), and mold (A. niger). The nanocomposite packaging films were effectively prevented the growth of microorganisms (coliforms, total microbial, and fungi) of the cheese during storage at low-temperature and showed microbial growth of less than 2.5 log CFU/g after 72 days of storage compared to the control group, and the quality of the packaged cheese was still acceptable.
CONCLUSION: The semolina-based nanocomposite films, especially Sem/Z3 K2 film, were effective for packaging of low moisture mozzarella cheese to maintain the physicochemical properties (pH, moisture, and fat content) and quality (color, taste, texture, and overall acceptability) of the cheese as well as preventing microbial growth (coliforms, total microbial, and fungi). © 2018 Society of Chemical Industry.

Matched MeSH terms: Cold Temperature
Fulltext Stability of Bacteriocin-Like Inhibitory Substance (BLIS) Produced by Pediococcus acidilactici kp10 at Different Extreme Conditions

Md Sidek NL, Halim M, Tan JS, Abbasiliasi S, Mustafa S, Ariff AB

Biomed Res Int, 2018;2018:5973484.
PMID: 30363649 DOI: 10.1155/2018/5973484

Nowadays, bacteriocin industry has substantially grown replacing the role of chemical preservatives in enhancing shelf-life and safety of food. The progress in bacteriocin study has been supported by the emerging of consumer demand on the applications of natural food preservatives. Since food is a complex ecosystem, the characteristics of bacteriocin determine the effectiveness of their incorporation into the food products. Among four commercial media (M17 broth, MRS broth, tryptic soy broth, and nutrient broth) tested, the highest growth of Pediococcus acidilactici kp10 and bacteriocin-like-inhibitory substance (BLIS) production were obtained in the cultivation with M17. BLIS production was found to be a growth associated process where the production was increased concomitantly with the growth of producing strain, P. acidilactici kp10. The antimicrobial property of BLIS against three indicator microorganisms (Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus) remained stable upon heating at 100°C but not detectable at 121°C. The BLIS activity was also observed to be stable and active at a wide pH range (pH 2 to pH 7). The BLIS activity remained constant at -20°C and -80°C for 1 month of storage. However, the activity dropped after 3 and 6 months of storage at 4°C, -20°C, and -80°C with more than 80% reduction. The ability of bacteriocin from P. acidilactici kp10 to inhibit food-borne pathogens while remaining stable and active at extreme pH and temperature is of potential interest for future applications in food preservatives.

Matched MeSH terms: Temperature
Fulltext Isolation and characterization of a 2,4-dinitrophenol-degrading bacterium

Noor Suffiah Md. Zin, Siti Nadzirah Padrilah, Mohd Fadhil Abd. Rahman, Koh, Sim Han, Ariff Khalid, Mohd. Yunus Shukor

Bioremediation Science and Technology Research, 2016;4(2):28-33.
MyJurnal

2,4-dinitrophenol (2,4-DNP) is utilized in the production of wood preservatives, dyes, and also
as a pesticide. Human acute (short-term) exposure to 2,4-DNP in humans by means of oral
exposure are nausea or vomiting, sweating, headaches, dizziness, and weight reduction. Thus, the
removal of this compound is highly sought. A 2,4-DNP-degrading bacterium (isolate 1) was
isolated from a sample soil from Terengganu. This bacterium (isolate 1) was characterized as a
rod Gram positive, non-sporulated, and non-motile bacterium. The bacterium is oxidase negative
and had catalase positive activity and was able to grow aerobically on 2,4-dinitrophenol as the
sole carbon source. This bacterium showed maximal growth on 2,4-DNP at the temperature
optimum of 30 oC, pH 5.0 and was tolerant to 2,4-DNP concentration of up to 0.5 mM (0.092
g/L). This bacterium prefers to use urea as the nitrogen source in addition to yeast extract for
mineral source and vitamin precursors.

Matched MeSH terms: Temperature
Rational Design of Thermostable Carbonic Anhydrase Mutants Using Molecular Dynamics Simulations

Parra-Cruz R, Jäger CM, Lau PL, Gomes RL, Pordea A

J Phys Chem B, 2018 09 13;122(36):8526-8536.
PMID: 30114369 DOI: 10.1021/acs.jpcb.8b05926

The stability of enzymes is critical for their application in industrial processes, which generally require different conditions from the natural enzyme environment. Both rational and random protein engineering approaches have been used to increase stability, with the latter requiring extensive experimental effort for the screening of variants. Moreover, some general rules addressing the molecular origin of protein thermostability have been established. Herein, we demonstrate the use of molecular dynamics simulations to gain molecular level understanding of protein thermostability and to engineer stabilizing mutations. Carbonic anhydrase (CA) is an enzyme with a high potential for biotechnological carbon capture applications, provided it can be engineered to withstand the high temperature process environments, inevitable in most gas treatment units. In this study, we used molecular dynamics simulations at 343, 353, and 363 K to study the relationship between structure flexibility and thermostability in bacterial α-CAs and applied this knowledge to the design of mutants with increased stability. The most thermostable α-CA known, TaCA from Thermovibrio ammonificans, had the most rigid structure during molecular dynamics simulations, but also showed regions with high flexibility. The most flexible amino acids in these regions were identified from root mean square fluctuation (RMSF) studies, and stabilizing point mutations were predicted based on their capacity to improve the calculated free energy of unfolding. Disulfide bonds were also designed at sites with suitable geometries and selected based on their location at flexible sites, assessed by B-factor calculation. Molecular dynamics simulations allowed the identification of five mutants with lower RMSF of the overall structure at 400 K, compared to wild-type TaCA. Comparison of free-energy landscapes between wild-type TaCA and the most promising mutants, Pro165Cys-Gln170Cys and Asn140Gly, showed an increased conformational stability of the mutants at 400 K.

Matched MeSH terms: Temperature
Fulltext A rapid inhibitive enzyme assay for monitoring heavy metals pollution in the Juru Industrial Estate

Halmi, M.I.E., Baskaran Gunasekaran, Othman, A.R., Shukor, M.Y., Kamaruddin, K., Dahalan, F.A., et al.

Bioremediation Science and Technology Research, 2015;3(2):7-12.
MyJurnal

The volume of contaminated rivers in Malaysia continues to keep rising through the years. The
cost of instrumental monitoring is uneconomical and prohibits schedule monitoring of
contaminants particularly heavy metals. In this work, a rapid enzyme assay utilizing the
molybdenum-reducing enzyme as an inhibitive assay, prepared in crude form from the
molybdenum-reducing bacterium Serratia sp. strain DRY5 has been developed for monitoring
the heavy metals mercury, silver, copper and chromium in contaminated waters in the Juru
Industrial Estate. The crude enzyme extract transformed soluble molybdenum
(phosphomolybdate) into a deep blue solution, which is inhibited by heavy metals such as
mercury, silver, copper and chromium. The IC50 and Limits of Detection (LOD) values for
mercury, copper, silver and cadmium were 0.245, 0.298, 0.367, 0.326, and 0.124, 0.086, 0.088
and 0.094 mg L-1, respectively. The assay is rapid, and can be carried out in less than 10 minutes.
In addition, the assay can be carried out at ambient temperature. The IC50 values for these heavy
metals are more sensitive than several established assays. Water samples from various locations
in the month of November from the Juru Industrial Estate (Penang) were tested for the presence
of heavy metals using the developed assay. Enzyme activity was nearly inhibited for water
samples from several locations. The presence of heavy metals was confirmed instrumentally
using Atomic Emission Spectrometry and a Flow Injection Mercury System. The assay is rapid
and simple and can be used as a first screening method for large scale monitoring of heavy
metals.

Matched MeSH terms: Temperature
Stability of Bioactive Compounds and Antioxidant Activities of Kenaf Seed Oil-in-Water Nanoemulsions under Different Storage Temperatures

Cheong AM, Tan CP, Nyam KL

J Food Sci, 2018 Oct;83(10):2457-2465.
PMID: 30178877 DOI: 10.1111/1750-3841.14332

Kenaf seed oil-in-water nanoemulsions (NANO) stabilized by sodium caseinate (SC), beta-cyclodextrin (β-CD), and Tween 20 (T20) have been optimized and shown to improve in vitro bioaccessibility and physicochemical stability in the previous study. The main objective of this study was to evaluate the stability of bioactive compounds and antioxidants in the NANO during storage at different temperatures (4 °C, 25 °C, and 40 °C). An evaluation of the antioxidant activities of each emulsifier showed that SC had good scavenging capability with 97.6% ABTS radical scavenging activity. Therefore, SC which was used as one of the main emulsifiers could further enhanced the antioxidant activity of NANO. At week 8 of storage, NANO that stored at 4 °C had maintained the best bioactive compounds stability and antioxidant activities with 90% retention of vitamin E and 65% retention of phytosterols. These results suggested that 4 °C would be the most suitable storage temperature for NANO containing naturally present vitamin E and phytosterols. From the accelerated storage results at 40 °C, NANO containing vitamin E and phytosterols had maintained half of its initial concentration until week 4 and week 2 of storage, which is equivalent to 16 weeks and 8 weeks of storage at room temperature, respectively.
PRACTICAL APPLICATION: The results of this study provide a better understanding on the stability of bioactive compounds and antioxidant activities in oil-in-water nanoemulsions that stabilized by similar ternary emulsifiers during storage at different temperatures. In addition, this study could be used as a predictive model to estimate the shelf life of bioactive compounds encapsulated in the form of nanoemulsions.

Matched MeSH terms: Temperature
Fulltext Isolation and characterization of a heavy metal-reducing Pseudomonas sp. strain Dr.Y Kertih with the ability to assimilate phenol and diesel

Veeraswamy Kesavan, Abdulrasheed Mansur, Mohd Syahmi Ramzi Salihan, Rahman, M.F., Suhaili, Zarizal, Shukor, M.Y.

Bioremediation Science and Technology Research, 2018;6(1):14-22.
MyJurnal

The indiscriminate released of heavy metals and xenobiotics into soils and aquatic bodies
severely alter soil organisms and the ecosystem. The isolation of xenobiotics degrading
microorganisms is cost-effective and naturally pleasant approach. Lately, the toxicological effect
of molybdenum to the spermatogenesis of several organisms has been record. This present study
is aimed at the isolation and characterization of a bacterium capable of converting molybdenum
to the colloidal molybdenum blue. Bacteria characterization was performed in a microplate
format using resting cells. Thus, the reduction process can be employed as a device for
molybdenum bioremediation. The results of the study revealed an optimum reduction at pH
between 6.0 and 6.3 and temperatures of between 25 and 40 oC. Similarly, it was also observed
that a phosphate concentration not greater than 5.0 mM and a sodium molybdate concentration
at 20 mM was required for reduction. Glucose was observed as the best carbon source to support
reduction. Following the scanning of molybdenum blue, it revealed an absorption spectrum
indicating the characteristics of molybdenum blue as a reduced phosphomolybdate. Molybdenum
reduction is inhibited by heavy metals like silver, lead, arsenic and mercury. Furthermore, the
ability of the bacterium (Pseudomonas sp. strain Dr.Y Kertih) to utilize several organic
xenobiotics such as phenol, acrylamide, nicotinamide, acetamide, iodoacetamide, propionamide,
acetamide, sodium dodecyl sulfate (SDS) and diesel as electron donor sources for aiding
reduction or as carbon sources for growth was also examined. Finding showed that none was
capable of aiding molybdenum reduction, however the bacterium was capable of growing on both
diesel and phenol as carbon sources. GC analysis was used to confirmed diesel degradation.

Matched MeSH terms: Temperature
Hydrodynamic cavitation assisted degradation of persistent endocrine-disrupting organochlorine pesticide Dicofol: Optimization of operating parameters and investigations on the mechanism of intensification

Panda D, Manickam S

Ultrason Sonochem, 2019 Mar;51:526-532.
PMID: 30224289 DOI: 10.1016/j.ultsonch.2018.04.003

Dicofol, a recommended Stockholm convention persistent organic pollutants (POPs) candidate is well known for its endocrine disruptive properties and has been extensively used as an organochlorine pesticide worldwide. The hydrodynamic cavitation (HC) treatment of Dicofol in aqueous media induced by a liquid whistle hydrodynamic cavitaion reactor (LWHCR) has been investigated while considering important parameters such as inlet pressure, initial concentration of Dicofol, solution temperature, pH, addition of H2O2 and radical scavenger for the extent of degradation. The pseudo-first-order degradation rate constant (k) was determined to be 0.073 min-1 with a cavitational yield of 1.26 × 10-5 mg/J at optimum operating conditions and a complete removal of Dicofol was achieved within 1 h of treatment. Considering the removal rate and energy efficiency, the optimal inlet pressure was found to be 7 bar, resulting in a cavitation number of 0.17. High performance liquid chromatography (HPLC) and Gas chromatography mass spectroscopy (GC-MS) analyses indicated a sharp decline in the concentration of Dicofol with treatment time and indicated the presence of degraded products. An 85% total organic carbon (TOC) removal was achieved within 1 h of treatment time, demonstrating successful mineralization of Dicofol. The obtained results suggest that the degradation of Dicofol followed thermal decomposition and successive recombination reactions at bubble-vapor interface. Overall, the attempted hydrodynamic cavitation demonstrated successful and rapid removal of endocrine disruptive chemicals such as Dicofol and is expected to provide efficient solution for wastewater treatment.

Matched MeSH terms: Temperature
From formulation of acrylamide-based hydrogels to their optimization for drug release using response surface methodology

Sabbagh F, Muhamad II, Nazari Z, Mobini P, Taraghdari SB

Mater Sci Eng C Mater Biol Appl, 2018 Nov 01;92:20-25.
PMID: 30184743 DOI: 10.1016/j.msec.2018.06.022

This study conducted on the structure of modified acrylamide-based hydrogel by synthesizing the nano composites. The hydrogels employed in this study were provided through a combination of acrylamide monomers, sodium carboxymethyl cellulose (NaCMC) and magnesium oxide (MgO) nanoparticles by crosslinking polymerization. N,N,N',N'-tetramethylethylenediamine and ammonium persulfate as the initiator was applied in the structure of the polymer. Findings of the study considered the nano composites consisting of MgO have the highest swelling ratio compared to pure Aam hydrogels. Thus, MgO is an appropriate nanoparticle to be used in the nano composites. Response surface methodology (RSM) based on a central composite design (CCD Design) was applied to optimize the preparation variables of a hydrogel consisted of MgO, NaCMC. With the swelling ratio for acrylamide-based hydrogel as the response, the effects of two variables, i.e. MgO and NaCMC were investigated. The effects of pH, temperature, MgO, and NaCMC on the drug release were investigated using the CCD design. The predicted appropriate drug release conditions for the hydrogel at the highest rate of temperature (37.50 °C) and pH: 4.10, is at its highest value, while the lower drug release is at temperature 38 °C and pH 3.50. With the desired value of MgO (0.01 g) and amount of NaCMC (0.1 g).

Matched MeSH terms: Temperature
Stability indicating HPLC method for simultaneous quantification of sildenafil citrate and dapoxetine hydrochloride in Pharmaceutical products

Liew KB, Peh KK

Pak J Pharm Sci, 2018 Nov;31(6):2515-2522.
PMID: 30473526

A stability-indicating HPLC-UV method for the simultaneous determination of sildenafil citrate and dapoxetine hydrochloride in solution and tablet was developed. The mobile phase was comprised of acetonitrile and 0.2M ammonium acetate buffer. The analyte was eluted at 3.392min and 7.255min for sildenafil citrate and dapoxetine HCl respectively using gradient system at a flow rate of 1.5mL/min. The theoretical plates count was>2000, tailing factor

Matched MeSH terms: Hot Temperature
Parametric optimization of polycaprolactone synthesis catalysed by Candida antarctica lipase B using response surface methodology

Pakalapati H, Arumugasamy SK, Jewaratnam J, Wong YJ, Khalid M

Biopolymers, 2018 Dec;109(12):e23240.
PMID: 30489632 DOI: 10.1002/bip.23240

A statistical approach with D-optimal design was used to optimize the process parameters for polycaprolactone (PCL) synthesis. The variables selected were temperature (50°C-110°C), time (1-7 h), mixing speed (50-500 rpm) and monomer/solvent ratio (1:1-1:6). Molecular weight was chosen as response and was determined using matrix-assisted laser desorption/ionization time of flight (MALDI TOF). Using the D-optimal method in design of experiments, the interactions between parameters and responses were analysed and validated. The results show a good agreement with a minimum error between the actual and predicted values.

Matched MeSH terms: Temperature
Fulltext Quantifying the genetic parameters of feed efficiency in juvenile Nile tilapia Oreochromis niloticus

de Verdal H, Vandeputte M, Mekkawy W, Chatain B, Benzie JAH

BMC Genet, 2018 11 16;19(1):105.
PMID: 30445908 DOI: 10.1186/s12863-018-0691-y

BACKGROUND: Improving feed efficiency in fish is crucial at the economic, social and environmental levels with respect to developing a more sustainable aquaculture. The important contribution of genetic improvement to achieve this goal has been hampered by the lack of accurate basic information on the genetic parameters of feed efficiency in fish. We used video assessment of feed intake on individual fish reared in groups to estimate the genetic parameters of six growth traits, feed intake, feed conversion ratio (FCR) and residual feed intake in 40 pedigreed families of the GIFT strain of Nile tilapia, Oreochromis niloticus. Feed intake and growth were measured on juvenile fish (22.4 g mean body weight) during 13 consecutive meals, representing 7 days of measurements. We used these data to estimate the FCR response to different selection criteria to assess the potential of genetics as a means of increasing FCR in tilapia.
RESULTS: Our results demonstrate genetic control for FCR in tilapia, with a heritability estimate of 0.32 ± 0.11. Response to selection estimates showed FCR could be efficiently improved by selective breeding. Due to low genetic correlations, selection for growth traits would not improve FCR. However, weight loss at fasting has a high genetic correlation with FCR (0.80 ± 0.25) and a moderate heritability (0.23), and could be an easy to measure and efficient criterion to improve FCR by selective breeding in tilapia.
CONCLUSION: At this age, FCR is genetically determined in Nile tilapia. A selective breeding program could be possible and could help enabling the development of a more sustainable aquaculture production.

Matched MeSH terms: Temperature
Microfluidic dielectrophoretic cell manipulation towards stable cell contact assemblies

Md Ali MA, Kayani ABA, Yeo LY, Chrimes AF, Ahmad MZ, Ostrikov KK, et al.

Biomed Microdevices, 2018 11 06;20(4):95.
PMID: 30402766 DOI: 10.1007/s10544-018-0341-1

Cell contact formation, which is the process by which cells are brought into close proximity is an important biotechnological process in cell and molecular biology. Such manipulation is achieved by various means, among which dielectrophoresis (DEP) is widely used due to its simplicity. Here, we show the advantages in the judicious choice of the DEP microelectrode configuration in terms of limiting undesirable effects of dielectric heating on the cells, which could lead to their inactivation or death, as well as the possibility for cell clustering, which is particularly advantageous over the linear cell chain arrangement typically achieved to date with DEP. This study comprises of experimental work as well as mathematical modeling using COMSOL. In particular, we establish the parameters in a capillary-based microfluidic system giving rise to these optimum cell-cell contact configurations, together with the possibility for facilitating other cell manipulations such as spinning and rotation, thus providing useful protocols for application into microfluidic bioparticle manipulation systems for diagnostics, therapeutics or for furthering research in cellular bioelectricity and intercellular interactions.

Matched MeSH terms: Hot Temperature
Effect of cogon grass fibre on the thermal, mechanical and biodegradation properties of thermoplastic cassava starch biocomposite

Jumaidin R, Khiruddin MAA, Asyul Sutan Saidi Z, Salit MS, Ilyas RA

Int J Biol Macromol, 2020 Mar 01;146:746-755.
PMID: 31730973 DOI: 10.1016/j.ijbiomac.2019.11.011

Thermoplastic cassava starch (TPCS) is a promising alternative material to replace the non-biodegradable petroleum based polymer due to its good environmental-friendly aspect i.e. abundant, sustainable, recyclable and biodegradable in nature. However, TPCS have some limitation such as poor mechanical properties. Therefore, in the present study, cogon grass fibre (CGF) were incorporated into TPCS using compression molding. Then the fundamental properties of CFG/TPCS biopolymer composites were carried out in order to evaluate their potential as a biodegradable reinforcement. From the study it was found that, the incorporation of CFG has improved the tensile and flexural properties of the TPCS composites, while the impact strength and elongation were reduced. The thermal properties of the biocomposite were reduced as the cogon grass fibres increase from 0 to 5%. In term of morphological, SEM shows good fibre adhesion between CGF and TPCS. Soil burial test shows that incorporation of CGF into TPCS has slow down the biodegradation process of the composites. Thus, CGF/TPCS biopolymer composites can be classified as composites with great potential as environmental-friendly material that biodegradable and renewable.

Matched MeSH terms: Temperature
Mechanical, antibacterial, and biocompatibility mechanism of PVD grown silver-tantalum-oxide-based nanostructured thin film on stainless steel 316L for surgical applications

Alias R, Mahmoodian R, Genasan K, Vellasamy KM, Hamdi Abd Shukor M, Kamarul T

Mater Sci Eng C Mater Biol Appl, 2020 Feb;107:110304.
PMID: 31761210 DOI: 10.1016/j.msec.2019.110304

Surgical site infection associated with surgical instruments has always been a factor in delaying post-operative recovery of patients. The evolution in surface modification of surgical instruments can be a potential choice to overcome the nosocomial infection mainly caused by bacterial populations such as Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. A study was, therefore, conducted characterising the morphology, hydrophobicity, adhesion strength, phase, Nano-hardness, surface chemistry, antimicrobial and biocompatibility of SS 316L steel deposited with a Nano-composite layer of Silver (Ag) and Tantalum oxide (Ta2O5) using physical vapour deposition magnetron sputtering. The adhesion strength of Ag/AgTa2O5 coating on SS 316L and treated at 250-850 °C of thermal treatment was evaluated using micro-scratch. The Ag/Ag-Ta2O5-400 °C was shown a 154% improvement in adhesion strength on SS 316L when compared with as-sputtered layer or Ag/Ag-Ta2O5-250, 550, 700 and 850 °C. The FESEM, XPS, and XRD indicated the segregation of Ag on the surface of SS 316L after the crystallization. Wettability and Nano-indentation tests demonstrated an increase in hydrophobicity (77.3 ± 0.3°) and Nano-hardness (1.12 ± 0.43 GPa) when compared with as-sputtered layer, after the 400 °C of thermal treatment. The antibacterial performance on Ag/Ag-Ta2O5-400 °C indicated a significant zone of inhibition to Staphylococcus aureus (A-axis: 16.33 ± 0.58 mm; B-axis: 25.67 ± 0.58 mm, p 

Matched MeSH terms: Hot Temperature

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