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  1. Fulltext Review of Functional Aspects of Nanocellulose-Based Pickering Emulsifier for Non-Toxic Application and Its Colloid Stabilization Mechanism
    Teo SH, Chee CY, Fahmi MZ, Wibawa Sakti SC, Lee HV
    Molecules, 2022 Oct 23;27(21).
    PMID: 36363998 DOI: 10.3390/molecules27217170
    In the past few years, the research on particle-stabilized emulsion (Pickering emulsion) has mainly focused on the usage of inorganic particles with well-defined shapes, narrow size distributions, and chemical tunability of the surfaces such as silica, alumina, and clay. However, the presence of incompatibility of some inorganic particles that are non-safe to humans and the ecosystem and their poor sustainability has led to a shift towards the development of materials of biological origin. For this reason, nano-dimensional cellulose (nanocellulose) derived from natural plants is suitable for use as a Pickering material for liquid interface stabilization for various non-toxic product formulations (e.g., the food and beverage, cosmetic, personal care, hygiene, pharmaceutical, and biomedical fields). However, the current understanding of nanocellulose-stabilized Pickering emulsion still lacks consistency in terms of the structural, self-assembly, and physio-chemical properties of nanocellulose towards the stabilization between liquid and oil interfaces. Thus, this review aims to provide a comprehensive study of the behavior of nanocellulose-based particles and their ability as a Pickering functionality to stabilize emulsion droplets. Extensive discussion on the characteristics of nanocelluloses, morphology, and preparation methods that can potentially be applied as Pickering emulsifiers in a different range of emulsions is provided. Nanocellulose's surface modification for the purpose of altering its characteristics and provoking multifunctional roles for high-grade non-toxic applications is discussed. Subsequently, the water-oil stabilization mechanism and the criteria for effective emulsion stabilization are summarized in this review. Lastly, we discuss the toxicity profile and risk assessment guidelines for the whole life cycle of nanocellulose from the fresh feedstock to the end-life of the product.
    Matched MeSH terms: Cellulose/chemistry; Emulsions/chemistry; Water/chemistry
  2. Investigation of optimal conditions for production of highly crystalline nanocellulose with increased yield via novel Cr(III)-catalyzed hydrolysis: Response surface methodology
    Chen YW, Lee HV, Abd Hamid SB
    Carbohydr Polym, 2017 Dec 15;178:57-68.
    PMID: 29050615 DOI: 10.1016/j.carbpol.2017.09.029
    For the first time, a highly efficient Cr(NO3)3 catalysis system was proposed for optimization the yield and crystallinity of nanocellulose end product. A five-level three-factor central composite design coupled with response surface methodology was employed to elucidate parameters interactions between three design factors, namely reaction temperature (x1), reaction time (x2) and concentration of Cr(NO3)3 (x3) over a broad range of process conditions and determine the effect on crystallinity index and product yield. The developed models predicted the maximum nanocellulose yield of 87% at optimum process conditions of 70.6°C, 1.48h, and 0.48M Cr(NO3)3. At these conditions, the obtained nanocellulose presented high crystallinity index (75.3%), spider-web-like interconnected network morphology with the average width of 31.2±14.3nm. In addition, the yielded nanocellulose rendered a higher thermal stability than that of original cellulosic source and expected to be widely used as reinforcement agent in bio-nanocomposites materials.
    Matched MeSH terms: Cellulose/chemistry*; Chromium Compounds/chemistry*; Nanoparticles/chemistry*
  3. Structured lipids produced from palm-olein oil by interesterification: A controllable lipase-catalyzed approach in a solvent-free system
    Ai H, Lee YY, Xie X, Tan CP, Ming Lai O, Li A, et al.
    Food Chem, 2023 Jun 30;412:135558.
    PMID: 36716631 DOI: 10.1016/j.foodchem.2023.135558
    Palm olein (POL) was modified by enzymatic interesterification with different degrees of acyl migration in a solvent-free packed bed reactor. The fatty acid and acylglycerol composition, isomer content, thermodynamic behavior, and relationship between crystal polymorphism, solid fat content (SFC), crystal microstructure, and texture before and after modification were studied. We found that the increase in sn-2 saturation interesterification was not only due to the generated tripalmitin (PPP) but also caused by acyl migration, and the SFC profiles were changed accordingly. The emergence of high melting point acylglycerols was an important factor accelerating the crystallization rate, further shortening the crystallization induction time, leading to the formation of large crystal spherulites, thereby reducing the hardness. The transformation from the β' to the β form occurred during post-hardening during storage. The isomer content also affected the physicochemical properties of the modified POL.
    Matched MeSH terms: Fatty Acids/chemistry; Glycerides/chemistry; Triglycerides/chemistry
  4. Recent advances in encapsulation of fat-soluble vitamins using polysaccharides, proteins, and lipids: A review on delivery systems, formulation, and industrial applications
    Wijekoon MMJO, Mahmood K, Ariffin F, Mohammadi Nafchi A, Zulkurnain M
    Int J Biol Macromol, 2023 Jun 30;241:124539.
    PMID: 37085081 DOI: 10.1016/j.ijbiomac.2023.124539
    Fat-soluble vitamins (FSVs) offer a range of beneficial properties as important nutrients in human nutrition. However, the high susceptibility to environmental conditions such as high temperature, light, and oxygen leads to the degradation of these compounds. This review highlights the different formulations underlying the encapsulation of FSVs in biopolymer (polysaccharide and protein) and lipid-based micro or nanocarriers for potential applications in food and pharmaceutical industries. In particular, the function of these carrier systems in terms of encapsulation efficiency, stability, bioavailability, and bio-accessibility is critically discussed. Recently, tremendous attention has been paid to encapsulating FSVs in commercial applications. According to the chemical nature of the active compound, the vigilant selection of delivery formulation, method of encapsulation, and final application (type of food) are the key important factors to be considered in the encapsulation of FSVs to ensure a high loading capacity, stability, bioavailability, and bio-accessibility. Future studies are recommended on the effect of different vitamin types and micro and nano encapsulate sizes on bioaccessibility and biocompatibility through in vitro/in vivo studies. Moreover, the toxicity and safety evaluation of encapsulated FSVs in human health should be evaluated before commercial application in food and pharmaceuticals.
    Matched MeSH terms: Lipids/chemistry; Polysaccharides/chemistry; Proteins/chemistry
  5. Structural elucidation of fucoidan from Cladosiphon okamuranus (Okinawa mozuku)
    Lim SJ, Wan Aida WM, Schiehser S, Rosenau T, Böhmdorfer S
    Food Chem, 2019 Jan 30;272:222-226.
    PMID: 30309536 DOI: 10.1016/j.foodchem.2018.08.034
    Fucoidan is a sulphated polysaccharide, made up mainly of l-fucose, which is found in brown seaweeds. Its chemical structure is diverse and depends on maturity, species and geographical location. The objective of this study was to elucidate the chemical structure of fucoidan from Cladosiphon okamuranus harvested in Japan. The fucoidan was subject to purification prior to monosaccharide profiling, sulphate content determination, and linkage analysis. Our results showed that Japanese Cladosiphon okamuranus fucoidan contained 70.13 ± 0.22 wt% fucose and 15.16 ± 1.17 wt% sulphate. Other minor monosaccharides found were d-xylose, d-galactose, d-mannose, d-glucose, d-arabinose, d-rhamnose and d-glucuronic acid. Linkage analysis revealed that fucopyranoside units along the backbone are linked, through α-1,3-glycosidic bonds, with fucose branching at C-2, and one sulphate group at C-4 per every three fucose units, i.e. the structure of fucoidan from Japanese Cladosiphon okamuranus is [→3)-α-fuc(1→]0.52[→3)-α-fuc-4-OSO3-(1→]0.33[→2)-α-fuc]0.14.
    Matched MeSH terms: Phaeophyta/chemistry*; Polysaccharides/chemistry*; Sulfates/chemistry
  6. Jackfruit peel cellulose nanocrystal - Alginate hydrogel for doripenem adsorption and release study
    Nyoo Putro J, Soetaredjo FE, Santoso SP, Irawaty W, Yuliana M, Wijaya CJ, et al.
    Int J Biol Macromol, 2024 Feb;257(Pt 1):128502.
    PMID: 38040139 DOI: 10.1016/j.ijbiomac.2023.128502
    As a natural raw material to replace synthetic chemicals, cellulose and its derivatives are the most popular choices in the pharmaceutical industry. For drug delivery applications, cellulose is usually used as a cellulose nanocrystal (CNC). CNC-based hydrogels are widely utilized for drug delivery because drug molecules can be encapsulated in their pore-like structures. This study aims to develop CNC hydrogels for the delivery of doripenem antibiotics. CNC was obtained from jackfruit peel extraction, and alginate was used as a network polymer to produce hydrogels. Ionotropic gelation was used in the synthesis of CNC-alginate hydrogel composites. The maximum adsorption of doripenem by CNC was 65.7 mg/g, while the maximum adsorption by CNC-alginate was 98.4 mg/g. One of the most challenging aspects of drug delivery is predicting drug release from a solid matrix using simple and complex mathematical equations. The sigmoidal equation could represent the doripenem release from CNC, while the Ritger-Peppas equation could describe the doripenem release from CNC-Alginate. The biocompatibility testing of CNC and CNC-alginate against a 7F2 cell line indicates that both materials were non-toxic.
    Matched MeSH terms: Alginates/chemistry; Cellulose/chemistry; Hydrogels/chemistry
  7. A comparative study on the influence of equipment design on the efficiency of dynamic maceration of Azadirachta excelsa leaves
    Letchumanan K, Abdullah NH, Abdul-Aziz A
    Prep Biochem Biotechnol, 2024 Jul;54(6):749-763.
    PMID: 37990367 DOI: 10.1080/10826068.2023.2282529
    Dynamic maceration facilitates diffusion in solid-liquid extraction through controlling temperature and providing agitation. However, equipment design for dynamic maceration in previous investigations resulted in inadequate homogeneity of temperature and solid dispersion. A laboratory scale extractor was designed to aid the heat and mass transfer process while preventing solvent vaporization when performing dynamic maceration in a controlled environment. This study aimed to evaluate the efficiency of dynamic maceration using the laboratory scale extractor compared to a shaker incubator to extract triterpenoid saponins from Azadirachta excelsa leaves. The dynamic maceration of A. excelsa leaves was optimized using a Face-centered central composite design (FCCCD) with response surface methodology (RSM). Independent variables analyzed include ethanol-to-chloroform ratio, extraction temperature, extraction time, and sample-to-solvent ratio, while responses include yield of extract and triterpenoid saponins content (TSC). Optimum conditions were ethanol-to-chloroform ratio of 90:10, extraction temperature of 45 °C, extraction time of 60 minutes, and sample-to-solvent ratio of 1:50 g/ml. There was a significant percentage of increase in yield of extract and TSC by 41.1% and 13.3%, respectively, for the laboratory scale extractor compared to the shaker incubator. This study showed the importance of equipment design in enhancing triterpenoid saponins extraction through elevating the efficiency of the dynamic maceration process.
    Matched MeSH terms: Ethanol/chemistry; Chloroform/chemistry; Solvents/chemistry
  8. Progress in food packaging applications of biopolymer-nanometal composites - A comprehensive review
    Chandrababu V, Parameswaranpillai J, Gopi JA, Pathak C, Midhun Dominic CD, Feng NL, et al.
    Biomater Adv, 2024 Sep;162:213921.
    PMID: 38870740 DOI: 10.1016/j.bioadv.2024.213921
    Eco-friendly nanotechnology-enabled biopolymers are one of the novel concepts of packaging materials to substitute traditional synthetic polymers and their composites. This article succinctly reviews the recent developments of introducing additional functionalities to biopolymers using metal and metal oxide nanoparticles. The functionality of metal nanoparticles such as silver, zinc oxide, titanium dioxide, copper oxide, gold, and magnesium oxide, as food packaging materials were discussed. The addition of nanoparticles in biopolymers improves mechanical properties, gas barrier properties, durability, temperature stability, moisture stability, antimicrobial activity, antioxidant property, and UV absorbance and can prevent the presence of ethylene and oxygen, hence extending the shelf life of foodstuffs. Other than this, the functional activity of these biopolymer composite films helps them to act like smart or intelligent packaging. The selection of metal nanoparticles, particle migration, toxicological effect, and potential future scope in the food packaging industry are also reviewed.
    Matched MeSH terms: Antioxidants/chemistry; Biopolymers/chemistry; Nanocomposites/chemistry
  9. A sustainable and economical solution for CO2 capture with biobased carbon materials derived from palm kernel shells
    Gopalan J, Buthiyappan A, Rashidi NA, Sufian S, Abdul Raman AA
    Environ Sci Pollut Res Int, 2024 Jul;31(33):45887-45912.
    PMID: 38980479 DOI: 10.1007/s11356-024-34173-1
    This study investigates the synthesize of activated carbon for carbon dioxide adsorption using palm kernel shell (PKS), a by-product of oil palm industry. The adsorbent synthesis involved a simple two-step carbonization method. Firstly, PKS was activated with potassium oxide (KOH), followed by functionalization with magnesium oxide (MgO). Surface analysis revealed that KOH activated PKS has resulted in a high specific surface area of 1086 m2/g compared to untreated PKS (435 m2/g). However, impregnation of MgO resulted in the reduction of surface area due to blockage of pores by MgO. Thermogravimetric analysis (TGA) demonstrated that PKS-based adsorbents exhibited minimal weight loss of less than 30% up to 500 °C, indicating their suitability for high-temperature applications. CO2 adsorption experiments revealed that PKS-AC-MgO has achieved a higher adsorption capacity of 155.35 mg/g compared to PKS-AC (149.63 mg/g) at 25 °C and 5 bars. The adsorption behaviour of PKS-AC-MgO was well fitted by both the Sips and Langmuir isotherms, suggesting a combination of both heterogeneous and homogeneous adsorption and indicating a chemical reaction between MgO and CO2. Thermodynamic analysis indicated a spontaneous and thermodynamically favourable process for CO2 capture by PKS-AC-MgO, with negative change in enthalpy (- 0.21 kJ/mol), positive change in entropy (2.44 kJ/mol), and negative change in Gibbs free energy (- 729.61 J/mol, - 790.79 J/mol, and - 851.98 J/mol) across tested temperature. Economic assessment revealed that the cost of PKS-AC-MgO is 21% lower than the current market price of commercial activated carbon, indicating its potential for industrial application. Environmental assessment shows a significant reduction in greenhouse gas emissions (381.9 tCO2) through the utilization of PKS-AC-MgO, underscoring its environmental benefits. In summary, the use of activated carbon produced from PKS and functionalised with MgO shows great potential for absorbing CO2. This aligns with the ideas of a circular economy and sustainable development.
    Matched MeSH terms: Carbon/chemistry; Charcoal/chemistry; Magnesium Oxide/chemistry
  10. Synthesis of cellulose nanofibers from jute fiber by using chemomechanical method
    N SS, M N EE, C K K, M J N
    F1000Res, 2024;13:40.
    PMID: 39246826 DOI: 10.12688/f1000research.138665.1
    BACKGROUND: Jute fiber is one of the most versatile natural fibers that is widely used as a raw material for packaging, textiles, and construction; and as a reinforcement in composite materials for heavy-duty applications. In the past, acid hydrolysis and mechanical treatment via the ball milling method were common in the extraction of cellulose nanofiber (CNFs) from natural plant fibers. However, there are some drawbacks of using those methods where there will be a huge quantity of acidic wastewater generated when the acid hydrolysis method is performed.

    METHOD: This study investigated the potential use of a combination of chemical and mechanical methods in the extraction of jute CNFs. Through this method, the jute fibers were first chemically treated using sodium hydroxide (NaOH), sodium chlorite (NaClO 2) and sulphuric acid (H 2SO 4) to remove the non-cellulosic elements followed by mechanical milling by using a planetary ball mill.

    RESULTS: The shape and size of the obtained CNFs were observed under a field emission scanning electron microscope (FESEM). This study revealed that jute CNFs were successfully extracted through the combination of chemical and mechanical treatment methods where the obtained CNFs reveal themselves in smooth fibrous morphology with a diameter of 23 nm and 150-200nm in length.

    CONCLUSIONS: Jute cellulose nanofibers were successfully drawn out from raw jute fibers by means of a combination of chemical and mechanical treatment. The results obtained confirmed that the chemomechanical method is an effective technique for isolating the CNFs and its potential use as reinforcement material was explained.

    Matched MeSH terms: Chlorides/chemistry; Sodium Hydroxide/chemistry; Sulfuric Acids/chemistry
  11. Sonochemical synthesis of gold nanoparticles by using high intensity focused ultrasound
    Yusof NS, Ashokkumar M
    Chemphyschem, 2015 Mar 16;16(4):775-81.
    PMID: 25598360 DOI: 10.1002/cphc.201402697
    The sonochemical synthesis of gold nanoparticles (GNPs) with different shapes and size distributions by using high-intensity focused ultrasound (HIFU) operating at 463 kHz is reported. GNP formation proceeds through the reduction of Au(3+) to Au(0) by radicals generated by acoustic cavitation. TEM images reveal that GNPs show irregular shapes at 30 W, are primarily icosahedral at 50 W and form a significant amount of nanorods at 70 W. The size of GNPs decreases with increasing acoustic power with a narrower size distribution. Sonochemiluminescence images help in the understanding of the effect of HIFU in controlling the size and shapes of GNPs. The number of radicals that form and the mechanical forces that are generated control the shape and size of the GNPs. UV/Vis spectra and TEM images are used to propose a possible mechanism for the observed effects. The results presented demonstrate, for the first time, that the HIFU system can be used to synthesise size- and shape-controlled metal nanoparticles.
    Matched MeSH terms: Gold/chemistry*; Metal Nanoparticles/chemistry*
  12. Quantitative correlation between counterion (X) affinity to cationic micelles and X-induced micellar growth for X = 2,4-; 2,5-; 2,6- and 3,4-dichlorobenzoate ions
    Yusof NS, Razak NA, Khan MN
    J Oleo Sci, 2013;62(5):257-69.
    PMID: 23648400
    A semi empirical kinetic (SEK) method has been used to determine the ratio of cetyltrimethylammonium bromide (CTABr) micellar binding constants of counterion X⁻ and Br⁻ (a reference counterion), i.e. K(X)/K(Br) (=R(X)(Br)). The values of K(X) and K(Br) have been derived from the kinetic parameters obtained in the presence spherical/non-spherical and spherical micelles, respectively. This rather new method gives the respective mean values of R(X)(Br) as 45±2, 25±3, 4.7±0.6 and 119±10 for X=2,4-, 2,5-, 2,6- and 3,4-Cl₂C₆H₃CO₂⁻ (Cl₂Bz'Na). Literature lacks the report on the values of R(X)(Br) for all X except for X=2,6-Cl₂C₆H₃CO₂⁻ (2,6-Cl2Bz'⁻) for which the reported value is 5.0. Rheological properties, such as shear thinning behavior, reveal indirectly the presence of wormlike micelles (WM) in the CTABr micellar solutions containing MX for all X except X=2,6-Cl₂Bz'⁻. The micelles remain spherical within [2,6-Cl₂Bz'⁻] range 0.01-0.34 M at 0.015 M CTABr. The maxima of the plots of zero shear viscosity, η₀, (obtained from the initial plateau region of flow curves, i.e. η vs. γ curve) vs. [MX] (MX=2,4-, 2,5- and 3,4-Cl₂Bz'Na) at 0.015 M CTABr also support indirectly the presence of linear, entangled and branched WM.
    Matched MeSH terms: Cetrimonium Compounds/chemistry*; Chlorobenzoates/chemistry*
  13. Unusual nitrogenous derivatives from Alstonia
    Tan SJ, Subramaniam G, Thomas NF, Kam TS
    Nat Prod Commun, 2012 Jun;7(6):739-42.
    PMID: 22816296
    Five new nitrogenous compounds were isolated from the Malayan Alstonia angustifolia and their structures determined based on interpretation of spectroscopic data.
    Matched MeSH terms: Alkaloids/chemistry*; Alstonia/chemistry*
  14. Fulltext Effect of annealing temperature on the optical spectra of CdS thin films deposited at low solution concentrations by Chemical Bath Deposition (CBD) Technique
    Rizwan Z, Zakaria A, Mohd Ghazali MS, Jafari A, Din FU, Zamiri R
    Int J Mol Sci, 2011;12(2):1293-305.
    PMID: 21541059 DOI: 10.3390/ijms12021293
    Two different concentrations of CdCl(2) and (NH(2))(2)CS were used to prepare CdS thin films, to be deposited on glass substrate by chemical bath deposition (CBD) technique. CdCl(2) (0.000312 M and 0.000625 M) was employed as a source of Cd(2+) while (NH(2))(2)CS (0.00125 M and 0.000625 M) for S(2-) at a constant bath temperature of 70 °C. Adhesion of the deposited films was found to be very good for all the solution concentrations of both reagents. The films were air-annealed at a temperature between 200 °C to 360 °C for one hour. The minimum thickness was observed to be 33.6 nm for film annealed at 320 °C. XRD analyses reveal that the films were cubic along with peaks of hexagonal phase for all film samples. The crystallite size of the films decreased from 41.4 nm to 7.4 nm with the increase of annealing temperature for the CdCl(2) (0.000312 M). Optical energy band gap (E(g)), Urbach energy (E(u)) and absorption coefficient (α) have been calculated from the transmission spectral data. These parameters have been discussed as a function of annealing temperature and solution concentration. The best transmission (about 97%) was obtained for the air-annealed films at higher temperature at CdCl(2) (0.000312 M).
    Matched MeSH terms: Sulfides/chemistry*; Cadmium Compounds/chemistry*
  15. Chemoenzymatic and microbial dynamic kinetic resolutions
    Kamaruddin AH, Uzir MH, Aboul-Enein HY, Halim HN
    Chirality, 2009 Apr;21(4):449-67.
    PMID: 18655180 DOI: 10.1002/chir.20619
    This review tracks a decade of dynamic kinetic resolution developments with a biocatalytic inclination using enzymatic/microbial means for the resolution part followed by the racemization reactions either by means of enzymatic or chemocatalyst. These fast developments are due to the ability of the biocatalysts to significantly reduce the number of synthetic steps which are common for conventional synthesis. Future developments in novel reactions and products of dynamic kinetic resolutions should consider factors that are needed to be extracted at the early synthetic stage to avoid inhibition at scale-up stage have been highlighted.
    Matched MeSH terms: Alcohols/chemistry; Carboxylic Acids/chemistry; Chemistry, Organic/methods*; Enzymes/chemistry; Esters/chemistry; Fenoprofen/chemistry; Fungal Proteins/chemistry*; Ibuprofen/chemistry; Naproxen/chemistry; Suprofen/chemistry
  16. Very long chain fatty acid methyl esters in transesterified palm oil
    Puah CW, Choo YM, Ma AN, Chuah CH
    Lipids, 2006 Mar;41(3):305-8.
    PMID: 16711607
    Some unidentified minor compounds have been observed in the residue from short-path distillation of transesterified palm oil that are not detected in the original palm oil. A method combining short-path distillation to enrich the unknowns with fractionation using solid-phase extraction is described. The fractionated components were identified using GC coupled with MS. The transesterified palm oil was found to contain methyl esters of up to C32 carbon atoms. In the very long chain FAME with carbon numbers > or = 20, both even and odd carbon numbers accounted for 0.26 wt%, with C24 and C26 being the major ones present in the residue after short-path distillation of transesterified palm oil.
    Matched MeSH terms: Fats, Unsaturated/chemistry; Plant Oils/chemistry*
  17. Reinereins A and B, new onocerane triterpenoids from Reinwardtiodendron cinereum
    Nugroho AE, Inoue D, Wong CP, Hirasawa Y, Kaneda T, Shirota O, et al.
    J Nat Med, 2018 Mar;72(2):588-592.
    PMID: 29453649 DOI: 10.1007/s11418-018-1188-8
    Bioactivity guided separation of Reinwardtiodendron cinereum barks methanol extract led to the isolation of two new onocerane triterpenoids, reinereins A and B (1 and 2), together with three known onocerane triterpenoids. Their structures were elucidated on the basis of NMR spectroscopic data. In vitro cytotoxic activities of the isolated compounds against several type of cancer cells were evaluated.
    Matched MeSH terms: Triterpenes/chemistry*; Meliaceae/chemistry*
  18. Pulsed electric field assisted process for extraction of bioactive compounds from custard apple (Annona squamosa) leaves
    Ahmad Shiekh K, Odunayo Olatunde O, Zhang B, Huda N, Benjakul S
    Food Chem, 2021 Oct 15;359:129976.
    PMID: 33957326 DOI: 10.1016/j.foodchem.2021.129976
    Impact of pulsed electric field (PEF) assisted process on preparation of custard apple leaf extract (CALE) using ethanol (70%, v/v) was studied. Different electric field strengths (2-6 kV/cm), pulse numbers (100-300 pulses) with specific energies (45-142 kJ/kg) for 2.5 to 5 min were implemented. Cell disintegration index was higher in CALE when PEF 6 kV/cm, 300 pulses, 142 kJ/kg for 5 min was applied. Extraction yield was higher (+5.2%) than the untreated counterpart (13.28%). Chlorophyll A and B contents were negligible in PEF pre-treated CALE. PEF improved radical scavenging activities assessed by DPPH, ABTS radical scavening activities and FRAP. The antibacterial properties of CALE against Staphylococcus aureus and Escherichia coli were highest. Purpureacin 2 and rutin were abundant in PEF pre-treated CALE. Therefore PEF was the potential aid in augmenting extraction yield and bioactivities of the extract from custard apple leaves.
    Matched MeSH terms: Plant Extracts/chemistry*; Annona/chemistry*
  19. Fulltext The presence of microplastics in commercial salts from different countries
    Karami A, Golieskardi A, Keong Choo C, Larat V, Galloway TS, Salamatinia B
    Sci Rep, 2017 04 06;7:46173.
    PMID: 28383020 DOI: 10.1038/srep46173
    The occurrence of microplastics (MPs) in saltwater bodies is relatively well studied, but nothing is known about their presence in most of the commercial salts that are widely consumed by humans across the globe. Here, we extracted MP-like particles larger than 149 μm from 17 salt brands originating from 8 different countries followed by the identification of their polymer composition using micro-Raman spectroscopy. Microplastics were absent in one brand while others contained between 1 to 10 MPs/Kg of salt. Out of the 72 extracted particles, 41.6% were plastic polymers, 23.6% were pigments, 5.50% were amorphous carbon, and 29.1% remained unidentified. The particle size (mean ± SD) was 515 ± 171 μm. The most common plastic polymers were polypropylene (40.0%) and polyethylene (33.3%). Fragments were the primary form of MPs (63.8%) followed by filaments (25.6%) and films (10.6%). According to our results, the low level of anthropogenic particles intake from the salts (maximum 37 particles per individual per annum) warrants negligible health impacts. However, to better understand the health risks associated with salt consumption, further development in extraction protocols are needed to isolate anthropogenic particles smaller than 149 μm.
    Matched MeSH terms: Plastics/chemistry*; Salts/chemistry*
  20. Strategy in manipulating transglycosylation activity of glycosyl hydrolase for oligosaccharide production
    Abdul Manas NH, Md Illias R, Mahadi NM
    Crit Rev Biotechnol, 2018 Mar;38(2):272-293.
    PMID: 28683572 DOI: 10.1080/07388551.2017.1339664
    BACKGROUND: The increasing market demand for oligosaccharides has intensified the need for efficient biocatalysts. Glycosyl hydrolases (GHs) are still gaining popularity as biocatalyst for oligosaccharides synthesis owing to its simple reaction and high selectivity.

    PURPOSE: Over the years, research has advanced mainly directing to one goal; to reduce hydrolysis activity of GHs for increased transglycosylation activity in achieving high production of oligosaccharides.

    DESIGN AND METHODS: This review concisely presents the strategies to increase transglycosylation activity of GHs for oligosaccharides synthesis, focusing on controlling the reaction equilibrium, and protein engineering. Various modifications of the subsites of GHs have been demonstrated to significantly modulate the hydrolysis and transglycosylation activity of the enzymes. The clear insight of the roles of each amino acid in these sites provides a platform for designing an enzyme that could synthesize a specific oligosaccharide product.

    CONCLUSIONS: The key strategies presented here are important for future improvement of GHs as a biocatalyst for oligosaccharide synthesis.

    Matched MeSH terms: Hydrolases/chemistry*; Oligosaccharides/chemistry*
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