Displaying publications 241 - 260 of 1854 in total

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  1. Effect of ratio of initial input materials on the liquefaction of empty fruit bunch (EFB)
    Ali Ahmadzadeh, Sarani Zakaria, Maisarah Yusoff
    Sains Malaysiana, 2009;38.
    The liquefaction of oil palm empty fruit bunch (EFB) in phenol was carried out in the presence of sulfuric acid as a catalyst in the reflux condenser system. The effect of initial phenol input and EFB on liquefaction reaction was investigated by measuring the reaction yield, EFB residue and combined phenol. The initial ratio of phenol to EFB has the greatest influence on the residue and reaction yield. The liquefaction products consist of some liquid by products with high amount of OH groups. The amount of this byproduct is 0.5 time of the solid product (phenolic resin).
    Matched MeSH terms: Sulfuric Acids
  2. One-step anodization of aluminum at room temperature
    Araoyinbo AO, Ahmad Fauzi M, Sreekantan S, Azizan Aziz
    Sains Malaysiana, 2009;38.
    The formation of nano pores on aluminum at 30oC- 38oC, employing a one step anodization technique which does not require removing the oxide layer formed is presented. A 20% phosphoric acid electrolyte (concentration higher than the normal anodization concentration of 5 to 10%) at a cell potential of 60 volts was used. A platinum electrode was used as the cathode electrode while the aluminum substrate as the anode electrode. A dc powered electrochemical cell to provide the required amount of current density (without the use of temperature controlled water bath) suitable or necessary for pore formation at room temperature was employed. The results obtained show that pore formation at room temperature is achievable and the pore diameter ranged between 80-120 nm.
    Matched MeSH terms: Phosphoric Acids
  3. Effect of filler and thermal aging on the mechanical properties of phenolated oil palm empty fruit bunch base composite
    Ali Ahmadzadeh, Sarani Zakaria, Rozaidi Rasid, Sharifah Nabihah
    Sains Malaysiana, 2008;37:233-237.
    Biofiber is used in the polymer based composite as a renewable resource due to its positive environmental benefits, biodegradable properties, low cost and high toughness. Biocomposite was fabricated using oil palm empty fruit bunch (EFB) as filler in phenolated EFB (PEFB) matrix. Phenolated EFB (PEFB) obtained from liquefaction of EFB in phenol was used as a biopolymer to replace novolak phenolic resin which is commonly used in composite materials. Sulfuric acid was used as a catalyst in the liquefaction reaction. The effect of thermal aging and blending ratio of PEFB matrix and EFB fibers on the mechanical properties of composites has been studied. The flexural data before and after thermal aging revealed the optimum amount of EFB filler is 50% . The result showed better compatibility between EFB and PEFB when compared with EFB and commercial novolak resin.
    Matched MeSH terms: Sulfuric Acids
  4. The effect of alkaline treatment on the mechanical properties of treated sugar palm yarn fibre reinforced unsaturated polyester composites reinforced with different fibre loadings of sugar palm fibre
    Mohd Nurazzi Norizan, Khalina Abdan, Mohd Sapuan Salit, Rahmah Mohamed
    Sains Malaysiana, 2018;47:699-705.
    The aim of this paper was to describe the effects of treated sugar palm yarn fibre loading on the mechanical properties
    of reinforced unsaturated polyester composites. Composites with varying fibre loads (10, 20, 30, 40 and 50 wt. %) were
    prepared using a hand-layup process. The composites were tested for tensile, flexural and impact strength according to
    ASTM D3930, ASTM D790 and ASTM D256 standards, respectively. The results showed that an increase in fibre loading
    of up to 30 wt. % increased tensile strength (31.27 MPa), tensile modulus (4.83 GPa), flexural strength (58.14 MPa)
    and modulus (4.48 GPa). Maximum loading can be attained at 40 wt. % of fibre loading for impact strength (38 kJ/
    m2). The effectiveness of stress transfer mechanism through the fibre-matrix interaction, coupled with the optimization
    of fibre loading in resisting fracture and failure, boosts the overall mechanical performance of sugar palm composite.
    Matched MeSH terms: Amino Acids
  5. Combination of gamma irradiation and sodium carbonate pretreatment on oil palm empty fruit bunch (efb) for high acidic hydrolysis yield
    Siew XC, Chin HC, Sarani Zakaria, Sahrim Ahmad, Siti Masrinda Tasirin
    Sains Malaysiana, 2017;46:167-173.
    Oil palm empty fruit bunch (EFB) fibres were pretreated by gamma irradiation followed by sodium carbonate (Na2
    CO3
    )
    before the acid hydrolysis process to produce reducing sugars using diluted sulphuric acid (H2
    SO4
    ). In this study, EFB
    fibres were irradiated at different doses, i.e. 0, 100 and 200 kGy. Meanwhile, the gamma irradiated sample were then
    subjected to Na2
    CO3 pretreatment with 0 and 5% total titratable alkali (TTA). The effect of the pretreatment using gamma
    irradiation and Na2
    CO3
    on the physical and chemical properties of the EFB fibres and the yield of the reducing sugar
    obtained from the acid hydrolysis process was investigated. The obtained results showed that the content of holocellulose
    was increased significantly with the increase of irradiation doses combined with Na2
    CO3 pretreatment, whereas lignin
    content of the EFB was decreased. The gamma irradiation and Na2
    CO3 pretreatment resulted in structure breakage
    and removal of silica of EFB fibres which can be due to the swelling of the fibres. A synergistic effect between gamma
    irradiation and Na2
    CO3 was observed, in which the yield of reducing sugars was increased by combining the gamma
    irradiation and Na2
    CO3 pretreatment.
    Matched MeSH terms: Sulfuric Acids
  6. Strategies to bioengineer aptamer-driven nanovehicles as exceptional molecular tools for targeted therapeutics: A review
    Thevendran R, Sarah S, Tang TH, Citartan M
    J Control Release, 2020 07 10;323:530-548.
    PMID: 32380206 DOI: 10.1016/j.jconrel.2020.04.051
    Aptamers are a class of folded nucleic acid strands capable of binding to different target molecules with high affinity and selectivity. Over the years, they have gained a substantial amount of interest as promising molecular tools for numerous medical applications, particularly in targeted therapeutics. However, only the different treatment approaches and current developments of aptamer-drug therapies have been discussed so far, ignoring the crucial technical and functional aspects of constructing a therapeutically effective aptamer-driven drug delivery system that translates to improved in-vivo performance. Hence, this paper provides a comprehensive review of the strategies used to improve the therapeutic performance of aptamer-guided delivery systems. We focus on the different functional features such as drug deployment, payload capacity, in-vivo stability and targeting efficiency to further our knowledge in enhancing the cell-specific delivery of aptamer-drug conjugates. Each reported strategy is critically discussed to emphasize both the benefits provided in comparison with other similar techniques and to outline their potential drawbacks with respect to the molecular properties of the aptamers, the drug and the system to be designed. The molecular architecture and design considerations for an efficient aptamer-based delivery system are also briefly elaborated.
    Matched MeSH terms: Nucleic Acids
  7. Development of 3-dimensional Co3O4 catalysts with various morphologies for activation of Oxone to degrade 5-sulfosalicylic acid in water
    Li MH, Da Oh W, Lin KA, Hung C, Hu C, Du Y
    Sci Total Environ, 2020 Jul 01;724:138032.
    PMID: 32408427 DOI: 10.1016/j.scitotenv.2020.138032
    Since 5-sulfosalicylic acid (SFA) has been increasingly released to the environment, SO4--based oxidation processes using Oxone have been considered as useful methods to eliminate SFA. As Co3O4 has been a promising material for OX activation, the four 3D Co3O4 catalysts with distinct morphologies, including Co3O4-C (with cubes), Co3O4-P (with plates), Co3O4-N (with needles) and Co3O4-F (with floral structures), are fabricated for activating OX to degrade SFA. In particular, Co3O4-F not only exhibits the highest surface area but also possesses the abundant Co2+ and more reactive surface, making Co3O4-F the most advantageous 3D Co3O4 catalyst for OX activation to degrade SFA. The mechanism of SFA by this 3D Co3O4/OX is also investigated and the corresponding SFA degradation pathway has been elucidated. The catalytic activities of Co3O4 catalysts can be correlated to physical and chemical properties which were associated with particular morphologies to provide insights into design of 3D Co3O4-based catalysts for OX-based technology to degrade emerging contaminants, such as SFA.
    Matched MeSH terms: Sulfuric Acids
  8. The giant mudskipper Periophthalmodon schlosseri facilitates active NH(4)(+) excretion by increasing acid excretion and decreasing NH(3) permeability in the skin
    Ip YK, Randall DJ, Kok TK, Barzaghi C, Wright PA, Ballantyne JS, et al.
    J Exp Biol, 2004 Feb;207(Pt 5):787-801.
    PMID: 14747411
    Periophthalmodon schlosseri is an amphibious and obligatory air-breathing teleost, which is extremely tolerant to environmental ammonia. It actively excretes NH(4)(+) in ammonia loading conditions. For such a mechanism to operate efficaciously the fish must be able to prevent back flux of NH(3). P. schlosseri could lower the pH of 50 volumes (w/v) of 50% seawater in an artificial burrow from pH 8.2 to pH 7.4 in 1 day, and established an ambient ammonia concentration of 10 mmol l(-1) in 8 days. It could alter the rate of titratable acid efflux in response to ambient pH. The rate of net acid efflux (H(+) excretion) in P. schlosseri was pH-dependent, increasing in the order pH 6.0<7.0<8.0<8.5. Net acid flux in neutral or alkaline pH conditions was partially inhibited by bafilomycin, indicating the possible involvement of a V-type H(+)-ATPase. P. schlosseri could also increase the rate of H(+) excretion in response to the presence of ammonia in a neutral (pH 7.0) external medium. Increased H(+) excretion in P. schlosseri occurred in the head region where active excretion of NH(4)(+) took place. This would result in high concentrations of H(+) in the boundary water layer and prevent the dissociation of NH(4)(+), thus preventing a back flux of NH(3) through the branchial epithelia. P. schlosseri probably developed such an 'environmental ammonia detoxification' capability because of its unique behavior of burrow building in the mudflats and living therein in a limited volume of water. In addition, the skin of P. schlosseri had low permeability to NH(3). Using an Ussing-type apparatus with 10 mmol l(-1) NH(4)Cl and a 1 unit pH gradient (pH 8.0 to 7.0), the skin supported only a very small flux of NH(3) (0.0095 micromol cm(-2) min(-1)). Cholesterol content (4.5 micromol g(-1)) in the skin was high, which suggests low membrane fluidity. Phosphatidylcholine, which has a stabilizing effect on membranes, constituted almost 50% of the skin phospholipids, with phosphatidyleserine and phsophatidylethanolamine contributing only 13% and 15%, respectively. More importantly, P. schlosseri increased the cholesterol level (to 5.5 micromol g(-1)) and altered the fatty acid composition (increased total saturated fatty acid content) in its skin lipid after exposure to ammonia (30 mmol l(-1) at pH 7.0) for 6 days. These changes might lead to an even lower permeability to NH(3) in the skin, and reduced back diffusion of the actively excreted NH(4)(+) as NH(3) or the net influx of exogenous NH(3), under such conditions.
    Matched MeSH terms: Acids/metabolism*; Fatty Acids/analysis
  9. Efficient conversion of lignocellulosic biomass to levulinic acid using acidic ionic liquids
    Khan AS, Man Z, Bustam MA, Nasrullah A, Ullah Z, Sarwono A, et al.
    Carbohydr Polym, 2018 Feb 01;181:208-214.
    PMID: 29253965 DOI: 10.1016/j.carbpol.2017.10.064
    In the present research work, dicationic ionic liquids, containing 1,4-bis(3-methylimidazolium-1-yl) butane ([C4(Mim)2]) cation with counter anions [(2HSO4)(H2SO4)0], [(2HSO4)(H2SO4)2] and [(2HSO4)(H2SO4)4] were synthesised. ILs structures were confirmed using 1H NMR spectroscopy. Thermal stability, Hammett acidity, density and viscosity of ILs were determined. Various types of lignocellulosic biomass such as rubber wood, palm oil frond, bamboo and rice husk were converted into levulinic acid (LA). Among the synthesized ionic liquids, [C4(Mim)2][(2HSO4)(H2SO4)4] showed higher % yield of LA up to 47.52 from bamboo biomass at 110°C for 60min, which is the better yield at low temperature and short time compared to previous reports. Surface morphology, surface functional groups and thermal stability of bamboo before and after conversion into LA were studied using SEM, FTIR and TGA analysis, respectively. This one-pot production of LA from agro-waste will open new opportunity for the conversion of sustainable biomass resources into valuable chemicals.
    Matched MeSH terms: Acids/pharmacology*; Levulinic Acids/metabolism*
  10. A comprehensive review on two-stage integrative schemes for the valorization of dark fermentative effluents
    Sivagurunathan P, Kuppam C, Mudhoo A, Saratale GD, Kadier A, Zhen G, et al.
    Crit Rev Biotechnol, 2018 Sep;38(6):868-882.
    PMID: 29264932 DOI: 10.1080/07388551.2017.1416578
    This review provides the alternative routes towards the valorization of dark H2 fermentation effluents that are mainly rich in volatile fatty acids such as acetate and butyrate. Various enhancement and alternative routes such as photo fermentation, anaerobic digestion, utilization of microbial electrochemical systems, and algal system towards the generation of bioenergy and electricity and also for efficient organic matter utilization are highlighted. What is more, various integration schemes and two-stage fermentation for the possible scale up are reviewed. Moreover, recent progress for enhanced performance towards waste stabilization and overall utilization of useful and higher COD present in the organic source into value-added products are extensively discussed.
    Matched MeSH terms: Fatty Acids, Volatile
  11. Determination of pitaya seeds as a natural antioxidant and source of essential fatty acids
    Chemah, T.C., Aminah, A., Noriham, A., Wan Aida, W.M.
    International Food Research Journal, 2010;17(4):1003-1010.
    MyJurnal
    The antioxidant capacity and total phenolic content of seeds of three types of pitaya namely Hylocereus polyrhizus, Hylocereus undatus and Selenicereus megalanthus and the fatty acid content of pitaya seeds oil were examined in this study. The ethanolic extracts of H. polyrhizus seeds showed significantly high (p
    Matched MeSH terms: Fatty Acids
  12. A review on superior advanced oxidation and photocatalytic degradation techniques for perfluorooctanoic acid (PFOA) elimination from wastewater
    Zango ZU, Khoo KS, Garba A, Kadir HA, Usman F, Zango MU, et al.
    Environ Res, 2023 Mar 15;221:115326.
    PMID: 36690243 DOI: 10.1016/j.envres.2023.115326
    Perfluorooctanoic acid (PFOA) has been identified as the most toxic specie of the family of perfluorinated carboxylic acids (PFCAs). It has been widely distributed and frequently detected in environmental wastewater. The compound's unique features such as inherent stability, rigidity, and resistance to harsh chemical and thermal conditions, due to its multiple and strong C-F bonds have resulted in its resistance to conventional wastewater remediations. Photolysis and bioremediation methods have been proven to be inefficient in their elimination, hence this article presents intensive literature studies and summarized findings reported on the application of advanced oxidation processes (AOPs) and photocatalytic degradation techniques as the best alternatives for the PFOA elimination from wastewater. Techniques of persulfate, photo-Fenton, electrochemical, photoelectrochemical and photocatalytic degradation have been explored and their mechanisms for the degradation and defluorination of the PFOA have been demonstrated. The major advantage of AOPs techniques has been centralized on the generation of active radicals such as sulfate (SO4•-) hydroxyl (•OH). While for the photocatalytic process, photogenerated species (electron (e) and holes (h + vb)) initiated the process. These active radicals and photogenerated species possessed potentiality to attack the PFOA molecule and caused the cleavage of the C-C and C-F bonds, resulting in its efficient degradation. Shorter-chain PFCAs have been identified as the major intermediates detected and the final stage entails its complete mineralization to carbon dioxide (CO2) and fluoride ion (F-). The prospects and challenges associated with the outlined techniques have been highlighted for better understanding of the subject matter for the PFOA elimination from real wastewaters.
    Matched MeSH terms: Carboxylic Acids
  13. Biomass and eicosapentaenoic acid production from Amphora sp. under different environmental and nutritional conditions
    Cheah YT, Ng BW, Tan TL, Chia ZS, Chan DJC
    Biotechnol Appl Biochem, 2023 Apr;70(2):568-580.
    PMID: 35767864 DOI: 10.1002/bab.2379
    Eicosapentaenoic acid (EPA) could be extracted from diatoms such as Amphora sp. present abundantly in the ecosystems. In view of the key environmental and nutritional factors governing the diatoms growth rate, culture conditions were optimized for the biomass yield, total lipid content, EPA yield, and fatty acid composition under two main cultivation regimes: photoautotrophic and heterotrophic. The fastest growth rate about 0.20 ± 0.02 g/L and the highest EPA yield about 9.19 ± 3.56 mg EPA/g biomass were obtained by adding 10 g/L glucose and sucrose, respectively. Under photoautotrophic culture conditions, Amphora sp. rendered higher EPA yield at 100 rpm and 16:8 light/dark cycle. Total fatty acids produced predominantly comprised of an approximate 40-70% of saturated fatty acids, followed by 10-27% of monounsaturated fatty acids and then 8-25% of polyunsaturated fatty acids. These findings were able to pave a way for huge-scale microalgal biomass production in commercial EPA production.
    Matched MeSH terms: Fatty Acids
  14. Fulltext Probing the substrate binding modes and catalytic mechanisms of BLEG-1, a promiscuous B3 metallo-β-lactamase with glyoxalase II properties
    Au SX, Mohd Padzil A, Muhd Noor ND, Matsumura H, Raja Abdul Rahman RNZ, Normi YM
    PLoS One, 2023;18(9):e0291012.
    PMID: 37672512 DOI: 10.1371/journal.pone.0291012
    BLEG-1 from Bacillus lehensis G1 is an evolutionary divergent B3 metallo-β-lactamase (MBL) that exhibited both β-lactamase and glyoxalase II (GLXII) activities. Sequence, phylogeny, biochemical and structural relatedness of BLEG-1 to B3 MBL and GLXII suggested BLEG-1 might be an intermediate in the evolutionary path of B3 MBL from GLXII. The unique active site cavity of BLEG-1 that recognizes both β-lactam antibiotics and S-D-lactoylglutathione (SLG) had been postulated as the key factor for its dual activity. In this study, dynamic ensembles of BLEG-1 and its substrate complexes divulged conformational plasticity and binding modes of structurally distinct substrates to the enzyme, providing better insights into its structure-to-function relationship and enzymatic promiscuity. Our results highlight the flexible nature of the active site pocket of BLEG-1, which is governed by concerted loop motions involving loop7+α3+loop8 and loop12 around the catalytic core, thereby moulding the binding pocket and facilitate interactions of BLEG-1 with both ampicillin and SLG. The distribution of (i) predominantly hydrophobic amino acids in the N-terminal domain, and (ii) flexible amino acids with polar and/or charged side chains in both N- and C-termini provide additional advantages to BLEG-1 in confining the aromatic group of ampicillin, and polar groups of SLG, respectively. The importance of these residues for substrates binding was further confirmed by the reduction in MBL and GLXII activities upon alanine substitutions of Ile-10, Phe-57, Arg-94, Leu-95, and Arg-159. Based on molecular dynamics simulation, mutational, and biochemical data presented herein, the catalytic mechanisms of BLEG-1 toward the hydrolysis of β-lactams and SLG were proposed.
    Matched MeSH terms: Amino Acids
  15. Fatty acid composition of breast milk from three racial groups from Penang, Malaysia
    Kneebone GM, Kneebone R, Gibson RA
    Am J Clin Nutr, 1985 Apr;41(4):765-9.
    PMID: 3984928 DOI: 10.1093/ajcn/41.4.765
    The fatty acid composition of samples of breast milk obtained from 51 mothers (26 Malay, 15 Chinese, 10 Indian) residing in Penang, Malaysia was determined by gas chromatography. Despite living in close physical proximity the mothers from the three racial groups showed distinct cultural differences in dietary intake. These differences were reflected in differences in the fatty acid composition of breast milk samples. The milk of Chinese mothers was generally less saturated (41%) than that of Malay and Indian mothers (52 and 50% respectively). The milk of Chinese mothers was also richer in linoleic acid (17%) than that of Malay and Indian mothers (9% and 11% respectively). Overall the level of individual fatty acids fell within the range of values reported for Western mothers on well nourished diets and pointed to breast milk of high standard despite large variations in the diet of Malaysian mothers.
    Matched MeSH terms: Fatty Acids/analysis*; Fatty Acids, Unsaturated/analysis
  16. Fulltext Morphological and biochemical responses of tropical seagrasses (Family: Hydrocharitaceae) under colonization of the macroalgae Ulva reticulata Forsskål
    Emmclan LSH, Zakaria MH, Ramaiya SD, Natrah I, Bujang JS
    PeerJ, 2022;10:e12821.
    PMID: 35111414 DOI: 10.7717/peerj.12821
    BACKGROUND: Coastal land development has deteriorated the habitat and water quality for seagrass growth and causes the proliferation of opportunist macroalgae that can potentially affect them physically and biochemically. The present study investigates the morphological and biochemical responses of seagrass from the Hydrocharitaceae family under the macroalgal bloom of Ulva reticulata, induced by land reclamation activities for constructing artificial islands.

    METHODS: Five seagrass species, Enhalus acoroides, Thalassia hemprichii, Halophila ovalis, Halophila major, and Halophila spinulosa were collected at an Ulva reticulata-colonized site (MA) shoal and a non-Ulva reticulata-colonized site (MC) shoal at Sungai Pulai estuary, Johor, Malaysia. Morphometry of shoots comprising leaf length (LL), leaf width (LW), leaf sheath length (LSL), leaflet length (LTL), leaflet width (LTW), petiole length (PL), space between intra-marginal veins (IV) of leaf, cross vein angle (CVA) of leaf, number of the cross vein (NOC), number of the leaf (NOL) and number of the leaflet (NOLT) were measured on fresh seagrass specimens. Moreover, in-situ water quality and water nutrient content were also recorded. Seagrass extracts in methanol were assessed for total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid radical cation scavenging activity (ABTS), and ferric reducing antioxidant power (FRAP).

    RESULTS: Seagrasses in the U. reticulata-colonized site (MA) had significantly higher (t-test, p < 0.05) leaf dimensions compared to those at the non-U. reticulata colonized site (MC). Simple broad-leaved seagrass of H. major and H. ovalis were highly sensitive to the colonization of U. reticulata, which resulted in higher morphometric variation (t-test, p < 0.05) including LL, PL, LW, and IV. Concerning the biochemical properties, all the seagrasses at MA recorded significantly higher (t-test, p < 0.05) TPC, TFC, and ABTS and lower DPPH and FRAP activities compared to those at MC. Hydrocharitaceae seagrass experience positive changes in leaf morphology features and metabolite contents when shaded by U. reticulata. Researching the synergistic effect of anthropogenic nutrient loads on the interaction between seagrasses and macroalgae can provide valuable information to decrease the negative effect of macroalgae blooms on seagrasses in the tropical meadow.

    Matched MeSH terms: Sulfonic Acids
  17. Analysis of natural okra extracts as corrosion inhibitors for mild steel in acidic medium
    Sulaimon AA, Murungi PI, Tackie-Otoo BN, Nwankwo PC, Bustam MA
    Environ Sci Pollut Res Int, 2023 Dec;30(56):119309-119328.
    PMID: 37924403 DOI: 10.1007/s11356-023-30635-0
    Plant extracts have been shown to effectively inhibit metal corrosion. Using the Box-Behnken design, gravimetric, and electrochemical techniques, analyses were designed to investigate the anti-corrosion potential of okra in a 1M HCl medium. The inhibition performances derived from the various methods were in good agreement, demonstrating that physio-chemisorption was effective and adhered to the Langmuir isotherm model. The efficiency of okra mucilage extract was 96% at a much lower concentration compared to 91.2% and 88.4% for the unsieved extract and gelly-okra filtrate, respectively. FTIR results showed the presence of several functional groups in the okra mucilage extract that are associated with adsorption, and TGA analysis revealed that the extract has high thermal stability. FESEM analysis also supported evidence of adsorption. It was determined that corrosion inhibition by okra mucilage extract was primarily influenced by temperature, followed by extract concentration, with immersion time having the least effect. From the model optimization, it was observed that okra mucilage extract at 200 ppm, 60°C, and 24 h gave an inhibition efficiency of 89.98% and high desirability. These results demonstrate the high capacity of natural okra as an efficient biodegradable corrosion inhibitor.
    Matched MeSH terms: Acids
  18. A gutsy performance: the potential for supplementation of short-chain fatty acids to benefit athletic health, exercise performance, and recovery
    Ong MLY, Green CG, Bongiovanni T, Heaney LM
    Benef Microbes, 2023 Dec 12;14(6):565-590.
    PMID: 38350483 DOI: 10.1163/18762891-20230069
    The gut microbiome is known to play an important role in the day-to-day physiology and health of the human host. It is, therefore, not surprising that there is interest surrounding the gut microbiome and its potential to benefit athletic health and performance. This has, in part, been driven by the consideration that gut bacterial by-products (i.e. metabolic waste) could be harnessed by the host and utilised for a beneficial outcome. The concept of harnessing bacterial metabolites as beneficial health modulators has developed the theory of leveraging short-chain fatty acids (SCFAs) as novel supplements for enhancing athletic performance. This review discusses the current literature investigating SCFA administration in cellular, animal, and human models, with the aim of linking the demonstrated physiological/biochemical mechanisms to potential exercise/athletic benefit. In addition, practical implications and factors relating to SCFA-supplementation in athletic populations are considered. The literature demonstrates a tangible rationale that SCFAs can have a positive impact on human physiology to afford benefits to the athletic population. These advantages include the capacity to improve respiratory immunity to combat elevated levels/severity of upper respiratory tract infections often reported in athletes; the blunting of pro-inflammatory and pro-fibrotic pathways to aid in exercise recovery; and the role of SCFAs as usable energy sources and metabolism modulators to fuel exercise and improve performance and/or endurance capacity. However, there is currently minimal research completed in human participants and thus further investigations into the direct benefit of SCFAs in exercise performance and/or recovery-based studies are required.
    Matched MeSH terms: Fatty Acids, Volatile
  19. Fulltext Fish oil supplements, oxidative status, and compliance behaviour: Regulatory challenges and opportunities
    Jairoun AA, Shahwan M, Zyoud SH
    PLoS One, 2020;15(12):e0244688.
    PMID: 33382790 DOI: 10.1371/journal.pone.0244688
    BACKGROUND: Fish oil supplements that are rich in omega-3 long-chain polyunsaturated fatty acids (n-3 PUFAs). PUFAs are among the most widely-used dietary supplements globally, and millions of people consume them regularly. There have always been public concerns that these products should be guaranteed to be safe and of good quality, especially as these types of fish oil supplements are extremely susceptible to oxidative degradation.

    OBJECTIVES: The aim of the current study is to investigate and examine the oxidation status of dietary supplements containing fish oils and to identify important factors related to the oxidation status of such supplements available in the United Arab Emirates (UAE).

    METHODS: A total of 44 fish oil supplements were analysed in this study. For each product, the oxidative parameters peroxide value (PV), anisidine value (AV), and total oxidation (TOTOX) were calculated, and comparisons were made with the guidelines supplied by the Global Organization for EPA and DHA Omega-3s (GOED). Median values for each of the above oxidative parameters were tested using the Kruskal-Wallis and Mann-Whitney U tests. P values < 0.05 were chosen as the statistically significant boundary.

    RESULTS: The estimate for the average PV value was 6.4 with a 95% confidence interval (CI) [4.2-8.7] compared to the maximum allowable limit of 5 meq/kg. The estimate for the average P-AV was 11 with a 95% CI [7.8-14.2] compared to the maximum allowable limit of 20. The estimate for the average TOTOX value was 23.8 meq/kg with a 95% CI [17.4-30.3] compared to the maximum allowable limit of 26 according to the GOED standards.

    CONCLUSION: This research shows that most, although not all, of the fish oil supplements tested are compliant with the GOED oxidative quality standards. Nevertheless, it is clear that there should be a high level of inspection and control regarding authenticity, purity, quality, and safety in the processes of production and supply of dietary supplements containing fish oils.

    Matched MeSH terms: Docosahexaenoic Acids/analysis; Fatty Acids, Omega-3/analysis
  20. Fulltext Production of chemoenzymatic catalyzed monoepoxide biolubricant: optimization and physicochemical characteristics
    Salimon J, Salih N, Abdullah BM
    J Biomed Biotechnol, 2012;2012:693848.
    PMID: 22346338 DOI: 10.1155/2012/693848
    Linoleic acid (LA) is converted to per-carboxylic acid catalyzed by an immobilized lipase from Candida antarctica (Novozym 435). This per-carboxylic acid is only intermediate and epoxidized itself in good yields and almost without consecutive reactions. Monoepoxide linoleic acid 9(12)-10(13)-monoepoxy 12(9)-octadecanoic acid (MEOA) was optimized using D-optimal design. At optimum conditions, higher yield% (82.14) and medium oxirane oxygen content (OOC) (4.91%) of MEOA were predicted at 15 μL of H(2)O(2), 120 mg of Novozym 435, and 7 h of reaction time. In order to develop better-quality biolubricants, pour point (PP), flash point (FP), viscosity index (VI), and oxidative stability (OT) were determined for LA and MEOA. The results showed that MEOA exhibited good low-temperature behavior with PP of -41(°)C. FP of MEOA increased to 128(°)C comparing with 115(°)C of LA. In a similar fashion, VI for LA was 224 generally several hundred centistokes (cSt) more viscous than MEOA 130.8. The ability of a substance to resist oxidative degradation is another important property for biolubricants. Therefore, LA and MEOA were screened to measure their OT which was observed at 189 and 168(°)C, respectively.
    Matched MeSH terms: Linoleic Acids/chemical synthesis; Linoleic Acids/metabolism; Linoleic Acids/chemistry*
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