Displaying publications 1 - 20 of 28 in total

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  1. Sivakumar M, Tang SY, Tan KW
    Ultrason Sonochem, 2014 Nov;21(6):2069-83.
    PMID: 24755340 DOI: 10.1016/j.ultsonch.2014.03.025
    Novel nanoemulsion-based drug delivery systems (DDS) have been proposed as alternative and effective approach for the delivery of various types of poorly water-soluble drugs in the last decade. This nanoformulation strategy significantly improves the cell uptake and bioavailability of numerous hydrophobic drugs by increasing their solubility and dissolution rate, maintaining drug concentration within the therapeutic range by controlling the drug release rate, and reducing systemic side effects by targeting to specific disease site, thus offering a better patient compliance. To date, cavitation technology has emerged to be an energy-efficient and promising technique to generate such nanoscale emulsions encapsulating a variety of highly potent pharmaceutical agents that are water-insoluble. The micro-turbulent implosions of cavitation bubbles tear-off primary giant oily emulsion droplets to nano-scale, spontaneously leading to the formation of highly uniform drug contained nanodroplets. A substantial body of recent literatures in the field of nanoemulsions suggests that cavitation is a facile, cost-reducing yet safer generation tool, remarkably highlighting its industrial commercial viability in the development of designing novel nanocarriers or enhancing the properties of existing pharmaceutical products. In this review, the fundamentals of nanoemulsion and the principles involved in their formation are presented. The underlying mechanisms in the generation of pharmaceutical nanoemulsion under acoustic field as well as the advantages of using cavitation compared to the conventional techniques are also highlighted. This review focuses on recent nanoemulsion-based DDS development and how cavitation through ultrasound and hydrodynamic means is useful to generate the pharmaceutical grade nanoemulsions including the complex double or submicron multiple emulsions.
  2. Tang SY, Shridharan P, Sivakumar M
    Ultrason Sonochem, 2013 Jan;20(1):485-97.
    PMID: 22633626 DOI: 10.1016/j.ultsonch.2012.04.005
    In the present investigation, the operating efficiency of a bench-top air-driven microfluidizer has been compared to that of a bench-top high power ultrasound horn in the production of pharmaceutical grade nanoemulsions using aspirin as a model drug. The influence of important process variables as well as the pre-homogenization and drug loading on the resultant mean droplet diameter and size distribution of emulsion droplets was studied in an oil-in-water nanoemulsion incorporated with a model drug aspirin. Results obtained show that both the emulsification methods were capable of producing very fine nanoemulsions containing aspirin with the minimum droplet size ranging from 150 to 170 nm. In case of using the microfluidizer, it has been observed that the size of the emulsion droplets obtained was almost independent of the applied microfluidization pressure (200-600 bar) and the number of passes (up to 10 passes) while the pre-homogenization and drug loading had a marginal effect in increasing the droplet size. Whereas, in the case of ultrasound emulsification, the droplet size was generally decreased with an increase in sonication amplitude (50-70%) and period of sonication but the resultant emulsion was found to be dependent on the pre-homogenization and drug loading. The STEM microscopic observations illustrated that the optimized formulations obtained using ultrasound cavitation technique are comparable to microfluidized emulsions. These comparative results demonstrated that ultrasound cavitation is a relatively energy-efficient yet promising method of pharmaceutical nanoemulsions as compared to microfluidizer although the means used to generate the nanoemulsions are different.
  3. Tang SY, Sivakumar M, Nashiru B
    Colloids Surf B Biointerfaces, 2013 Feb 1;102:653-8.
    PMID: 23107943 DOI: 10.1016/j.colsurfb.2012.08.036
    The present investigation focuses in investigating the effect of osmotic pressure, gelling on the mean droplet diameter, polydispersity index, droplet size stability of the developed novel Aspirin containing water-in-oil-in-water (W/O/W) nano multiple emulsion. The aspirin-loaded nano multiple emulsion formulation was successfully generated using two-stage ultrasonic cavitational emulsification which had been reported in author's previous study. The osmotic behavior of ultrasonically prepared nano multiple emulsions were also examined with different glucose concentrations both in the inner and outer aqueous phases. In addition, introducing gelatin into the formulation also observed to play an important role in preventing the interdroplet coalescence via the formation of interfacial rigid film. Detailed studies were also made on the possible mechanisms of water migration under osmotic gradient which primarily caused by the permeation of glucose. Besides, the experimental results have shown that the interfacial tension between the two immiscible phases decreases with varying the composition of organic phase. Although the W/O/W emulsion prepared with the inner/outer glucose weight ratio of 1-0.5% (w/w) showed an excellent droplet stability, the formulation containing 0.5% (w/w) glucose in the inner aqueous phase appeared to be the most stable with minimum change in the mean droplet size upon one-week storage period. Based on the optimization, nano multiple emulsion droplets with the mean droplet diameter of around 400 nm were produced using 1.25% (w/w) Span 80 and 0.5% Cremophore EL. Overall, our investigation makes a pathway in proving that the use of ultrasound cavitation is an efficient yet promising approach in the generation of stable and uniform nano multiple emulsions and could be used in the encapsulation of various active pharmaceutical ingredients in the near future.
  4. Tang SY, Manickam S, Wei TK, Nashiru B
    Ultrason Sonochem, 2012 Mar;19(2):330-45.
    PMID: 21835676 DOI: 10.1016/j.ultsonch.2011.07.001
    In the present study, response surface methodology (RSM) based on central composite design (CCD) was employed to investigate the influence of main emulsion composition variables, namely drug loading, oil content, emulsifier content as well as the effect of the ultrasonic operating parameters such as pre-mixing time, ultrasonic amplitude, and irradiation time on the properties of aspirin-loaded nanoemulsions. The two main emulsion properties studied as response variables were: mean droplet size and polydispersity index. The ultimate goal of the present work was to determine the optimum level of the six independent variables in which an optimal aspirin nanoemulsion with desirable properties could be produced. The response surface analysis results clearly showed that the variability of two responses could be depicted as a linear function of the content of main emulsion compositions and ultrasonic processing variables. In the present investigation, it is evidently shown that ultrasound cavitation is a powerful yet promising approach in the controlled production of aspirin nanoemulsions with smaller average droplet size in a range of 200-300 nm and with a polydispersity index (PDI) of about 0.30. This study proved that the use of low frequency ultrasound is of considerable importance in the controlled production of pharmaceutical nanoemulsions in the drug delivery system.
  5. Tang SY, Hara S, Melling L, Goh KJ, Hashidoko Y
    Biosci Biotechnol Biochem, 2010;74(9):1972-5.
    PMID: 20834139
    Root-associating bacteria of the nipa palm (Nypa fruticans), preferring brackish-water affected mud in Sarawak, Malaysia, were investigated. In a comparison of rhizobacterial microbiota between the nipa and the sago (Metroxylon sagu) palm, it was found that the nipa palm possessed a group of Burkholderia vietnamiensis as its main active nitrogen-fixing endophytic bacterium. Acetylene reduction by the various isolates of B. vietnamiensis was constant (44 to 68 nmol h(-1) in ethylene production rate) in soft gel medium containing 0.2% sucrose as sole carbon source, and the bacterium also showed motility and biofilm-forming capacity. This is the first report of endophytic nitrogen-fixing bacteria from nipa palm.
  6. Suzana S, Hanis MY, Tang SY, Ayiesah R, Roslina AM
    Malays J Nutr, 2008 Sep;14(2):151-62.
    PMID: 22691772 MyJurnal
    This quasi-experimental study was carried out to evaluate the effectiveness of an eight-week multi-disciplinary pulmonary rehabilitation programme in improving nutritional and functional status and quality of life of COPD out patients at Hospital Universiti Kebangsaan Malaysia. A total of 9 COPD outpatients aged 40 years and above (6 men and 3 women) completed at least 50% of 16 sessions of an eight-week pulmonary rehabilitation programme. Their nutritional and functional status and rating of quality of life were measured at baseline (0 day) and after 8 weeks and these were compared to those of the control group matched for age, comprising 13 subjects (11 men and 2 women). Nutritional status was determined using anthropometry, body composition (Bioelectrical Impedance Analysis) and three-day food record. Assessment of appetite for food was also carried out using the Simplified Nutritional Assessment Questionnaire (SNAQ). Functional status was assessed using the Pulmonary Functional Status and Dyspnea Questionnaire-modified version(PFSDQ-M). The handgrip strength was also measured using handgrip dynamometer. The SF36 questionnaire was used to measure the quality of life of the subjects. There was a reduction in dyspnea (-49.0%, p<0.05) and fatigue (-47.8%, p<0.05) in men after the intervention programme, as compared to their controls (dyspnea -2.9% and fatigue 8.9%). Quality of life in this group was also significantly improved by 31.8% (p<0.05) as compared to their controls (-3.0%,p>0.05). Similar trends were noted for the women, although the difference was not significant. No significant changes were seen in nutritional status assessed by anthropometry, dietary intake and appetite. However, there was a trend of increased nutrient intake and SNAQ score in the intervention group as compared to control. An eight-week pulmonary rehabilitation programme was effective in improving the functional status particularly in men, by reducing dyspnea and fatigue; and also improving their quality of life, but was not effective in changing the nutritional status.
    Study site: Physiotherapy Unit, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
  7. Tang SY, Sivakumar M, Ng AM, Shridharan P
    Int J Pharm, 2012 Jul 1;430(1-2):299-306.
    PMID: 22503988 DOI: 10.1016/j.ijpharm.2012.03.055
    The present study investigated the anti-inflammatory and analgesic activities of novel aspirin oil-in-water (O/W) nanoemulsion and water-in-oil-in-water (W/O/W) nano multiple emulsion formulations generated using ultrasound cavitation techniques. The anti-inflammatory activities of nanoemulsion and nano multiple emulsion were determined using the λ-carrageenan-induced paw edema model. The analgesic activities of both nanoformulations were determined using acetic acid-induced writhing response and hot plate assay. For comparison, the effect of pretreatment with blank nanoemulsion and reference aspirin suspension were also studied for their anti-inflammatory and antinociceptive activities. The results showed that oral administration of nanoemulsion and nano multiple emulsion containing aspirin (60 mg/kg) significantly reduced paw edema induced by λ-carrageenan injection. Both nanoformulations decreased the number of abdominal constriction in acetic acid-induced writhing model. Pretreatment with nanoformulations led to a significant increase in reaction time in hot plate assay. Nanoemulsion demonstrated an enhanced anti-inflammatory and analgesic effects compared to reference suspension while nano multiple emulsion exhibited a mild inhibitory effects in the three experimental animal model tests. The results obtained for nano multiple emulsion were relatively lower than reference. However, administration of blank nanoemulsion did not alter the nociceptive response significantly though it showed slight anti-inflammatory effect. These experimental studies suggest that nanoemulsion and nano multiple emulsion produced a pronounced anti-inflammatory and analgesic effects in rats and may be candidates as new nanocarriers for pharmacological NSAIDs in the treatment of inflammatory disorders and alleviating pains.
  8. Kaur S, Ng CM, Tang SY, Kok EY
    Chronobiol Int, 2023 Apr;40(4):406-415.
    PMID: 36883329 DOI: 10.1080/07420528.2023.2186120
    This study aimed to examine the association between chronotype, eating jetlag, and eating misalignment with weight status among Malaysian adults during the COVID-19 restriction. This online cross-sectional study included 175 working adults recruited from March to July 2020. The chronotype was assessed using Morningness Eveningness Questionnaire (MEQ) while eating jetlag and mealtime variability were measured using Chrononutrition Profile Questionnaire (CPQ). Multiple linear regression demonstrated that lower breakfast frequency (β = -0.258, p = .002) and longer eating duration (β = 0.393, p 
  9. Ong WD, Tey BT, Quek SY, Tang SY, Chan ES
    J Food Sci, 2015 Jan;80(1):E93-E100.
    PMID: 25529579 DOI: 10.1111/1750-3841.12729
    Oil-in-water (O/W) emulsion-gel systems containing high oil payloads are of increasing interest for food applications because of the reduction in encapsulation cost, consumption frequency or volume of food products. This study shows a facile approach to prepare stable alginate-based O/W emulsions at high oil loading using a mixture of nonionic surfactants (Tween 80 and Span 20) as a template to form gelled-emulsions. The synergistic effects of alginate and surfactants on the O/W emulsion properties were evaluated in terms of oil droplet size and emulsion stability. At 2% (w/v) of alginate and 1% (w/v) of surfactants, the size distribution of oil droplets was narrow and monomodal, even at an oil loading of 70% (v/v). The emulsions formed were stable against phase separation. The oil droplet size could be further reduced to below 1 μm using a high-shear homogenizer. The emulsions formed could be easily molded and gelled into solids of different shapes via ionic gelation. The findings of this study create possible avenues for applications in food industries.
  10. Low LE, Tan LT, Goh BH, Tey BT, Ong BH, Tang SY
    Int J Biol Macromol, 2019 Apr 15;127:76-84.
    PMID: 30639596 DOI: 10.1016/j.ijbiomac.2019.01.037
    Stimuli-responsive drug release and controlled delivery play crucial roles in enhancing the therapeutic efficacy and lowering over-dosage induced side effects. In this paper, we report magnetically-triggered drug release and in-vitro anti-colon cancer efficacy of Fe3O4@cellulose nanocrystal (MCNC)-stabilized Pickering emulsions containing curcumin (CUR). The loading efficiency of CUR in the micron-sized (≈7 μm) MCNC-stabilized Pickering emulsions (MCNC-PE) template was found to be 99.35%. The drug release profiles showed that the exposure of MCNC-PE to external magnetic field (EMF) (0.7 T) stimulated the release of bioactive from MCNC-PE achieving 53.30 ± 5.08% of the initial loading over a 4-day period. The MTT assay demonstrated that the CUR-loaded MCNC-PE can effectively inhibits the human colon cancer cells growth down to 18% in the presence of EMF. The formulation also resulted in 2-fold reduction on the volume of the 3-D multicellular spheroids of HCT116 as compared to the control sample. The MCNC particle was found to be non-toxic to brine shrimp up to a concentration of 100 μg/mL. Our findings suggested that the palm-based MCNC-PE could be a promising yet effective colloidal drug delivery system for magnetic-triggered release of bioactive and therapeutics.
  11. Low DYS, Supramaniam J, Soottitantawat A, Charinpanitkul T, Tanthapanichakoon W, Tan KW, et al.
    Polymers (Basel), 2021 Feb 12;13(4).
    PMID: 33673391 DOI: 10.3390/polym13040550
    Research and development of nanocellulose and nanocellulose-reinforced composite materials have garnered substantial interest in recent years. This is greatly attributed to its unique functionalities and properties, such as being renewable, sustainable, possessing high mechanical strengths, having low weight and cost. This review aims to highlight recent developments in incorporating nanocellulose into rubber matrices as a reinforcing filler material. It encompasses an introduction to natural and synthetic rubbers as a commodity at large and conventional fillers used today in rubber processing, such as carbon black and silica. Subsequently, different types of nanocellulose would be addressed, including its common sources, dimensions, and mechanical properties, followed by recent isolation techniques of nanocellulose from its resource and application in rubber reinforcement. The review also gathers recent studies and qualitative findings on the incorporation of a myriad of nanocellulose variants into various types of rubber matrices with the main goal of enhancing its mechanical integrity and potentially phasing out conventional rubber fillers. The mechanism of reinforcement and mechanical behaviors of these nanocomposites are highlighted. This article concludes with potential industrial applications of nanocellulose-reinforced rubber composites and the way forward with this technology.
  12. Siva SP, Kow KW, Chan CH, Tang SY, Ho YK
    Ultrason Sonochem, 2019 Jul;55:348-358.
    PMID: 30871878 DOI: 10.1016/j.ultsonch.2018.12.040
    The dynamics of droplet breakup during emulsification is a complicated process due to the interplay between multiple physico-chemical and hydrodynamic factors, especially in an energy-intensive ultrasound-assisted emulsification process. In this work, by mapping the physical processing parameters of ultrasound emulsification into a reduced domain that is governed by the power density and the initial average droplet diameter, a dimensionless parameter that resembles the dynamic breakup potential (η) was established via dimensional analysis. In addition to shedding important insights into the emulsification process, η further facilitates the establishment of a transient scaling relationship that is a function of the characteristic value (a) of the emulsion system. Experimental case study on a cellulose nanocrystals (CNC)-based olein-in-water emulsion system prepared via ultrasound cavitation confirmed the validity of the scaling relationship and sub-universal self-similarity was observed. Using the proposed model, good predictions of the transient of droplet size evolution were attained where the value of η, i.e. the proportionality constant, can be conveniently computed using data from a single time point. Application on other emulsion systems further suggested that the value of a possibly indicates the relative minimum size limit of a particular fluids-emulsifier system. Our approach is general, which encourages widespread adoption for emulsification related studies.
  13. Low LE, Tey BT, Ong BH, Chan ES, Tang SY
    Carbohydr Polym, 2017 Jan 02;155:391-399.
    PMID: 27702526 DOI: 10.1016/j.carbpol.2016.08.091
    We studied the formation of palm olein-in-water (O/W) Pickering emulsion stabilized by Fe3O4-cellulose nanocrystals (MCNC) nanocomposites obtained by ultrasound assisted in-situ co-precipitation method. The synthesized MCNC nanocomposites successfully stabilized Pickering emulsion with dual responses. The magnetic tests revealed a direct-relation between attractability of MCNC-stabilized Pickering emulsions and the emulsion droplet diameter. The Pickering emulsions were stable under pH ranging from 3 to 6. The stability substantially reduced around pH 8-10, and regained slowly when approaching pH 13. From microscopic and mastersizer analysis, monodisperse emulsion droplets were noticed at pH 3-6, and 13, while polydisperse emulsion were obtained at pH 8-12. The Pickering emulsions prepared at pH 6 are stable up to 14 days, while Pickering emulsions at pH 8 experienced coalescence. In this study, the dual stimuli-responsive Pickering emulsion stabilized by MCNC may hold potentials for biomedical and drug delivery as new generation of smart nanotherapeutic carrier.
  14. Hoo DY, Low ZL, Low DYS, Tang SY, Manickam S, Tan KW, et al.
    Ultrason Sonochem, 2022 Nov;90:106176.
    PMID: 36174272 DOI: 10.1016/j.ultsonch.2022.106176
    With rising consumer demand for natural products, a greener and cleaner technology, i.e., ultrasound-assisted extraction, has received immense attention given its effective and rapid isolation for nanocellulose compared to conventional methods. Nevertheless, the application of ultrasound on a commercial scale is limited due to the challenges associated with process optimization, high energy requirement, difficulty in equipment design and process scale-up, safety and regulatory issues. This review aims to narrow the research gap by placing the current research activities into perspectives and highlighting the diversified applications, significant roles, and potentials of ultrasound to ease future developments. In recent years, enhancements have been reported with ultrasound assistance, including a reduction in extraction duration, minimization of the reliance on harmful chemicals, and, most importantly, improved yield and properties of nanocellulose. An extensive review of the strengths and weaknesses of ultrasound-assisted treatments has also been considered. Essentially, the cavitation phenomena enhance the extraction efficiency through an increased mass transfer rate between the substrate and solvent due to the implosion of microbubbles. Optimization of process parameters such as ultrasonic intensity, duration, and frequency have indicated their significance for improved efficiency.
  15. Wong SK, Supramaniam J, Wong TW, Soottitantawat A, Ruktanonchai UR, Tey BT, et al.
    Carbohydr Res, 2021 Jun;504:108336.
    PMID: 33964507 DOI: 10.1016/j.carres.2021.108336
    The development of hybrid polysaccharide-protein complexes as Pickering emulsion stabilizers has attracted increasing research interest in recent years. This work presents an eco-friendly surface modification strategy to functionalize hydrophilic cellulose nanocrystals (CNC) using hydrophobic soy protein isolate (SPI) via mussel adhesive-inspired poly (l-dopa) (PLD) to develop improved nanoconjugates as stabilizers for oil-in-water Pickering emulsion. The physicochemical properties of the CNC-PLD-SPI nanoconjugate were evaluated by solid-state 13C NMR, FT-IR, TGA, XRD, contact angle analysis, and TEM. The modified CNC (conjugation content of 38.22 ± 1.21%) had lowered crystallinity index, higher thermal stability, and more hydrophobic than unmodified CNC, with an average particle size of 309.9 ± 8.0 nm. Use of amphiphilic CNC-PLD-SPI nanoconjugate with greater conformational flexibility as Pickering stabilizer produced oil-in-water emulsions with greater physical stability.
  16. Tang SY, Tan CH, Sim KS, Yong KT, Lim KH, Low YY, et al.
    Phytochemistry, 2023 Apr;208:113587.
    PMID: 36646163 DOI: 10.1016/j.phytochem.2023.113587
    Eight undescribed iboga alkaloids, polyneurines A-H, were isolated from the bark of Tabernaemontana polyneura. The structures of these alkaloids were established by interpretation of the MS and NMR data, while the configurations were determined using GIAO NMR calculations and DP4+ probability analysis, TDDFT-ECD method, or X-ray diffraction analysis. Polyneurine A possesses a γ-lactone unit embedded within the iboga skeleton, while polyneurines D and E incorporate a formylmethyl moiety at C-3 of the iboga skeleton. Biosynthetic pathways towards the formation of polyneurines A, C, D, and E were proposed.
  17. How SW, Low DYS, Leo BF, Manickam S, Goh BH, Tang SY
    J Hosp Infect, 2023 Jul;137:24-34.
    PMID: 37044283 DOI: 10.1016/j.jhin.2023.03.022
    Following recent viral outbreaks, there has been a significant increase in global demand for gloves. Biomedical research focuses increasingly on antimicrobial gloves to combat microbial transmission and hospital-acquired infections. Most antimicrobial gloves are manufactured using antimicrobial chemicals such as disinfectants, biocides and sanitizers. The design of antimicrobial gloves incorporates advanced technologies, including colloidal particles and nanomaterials, to enhance antimicrobial effectiveness. A category of antimicrobial gloves also explores and integrates natural antimicrobial benefits from animals, plants and micro-organisms. Many types of antimicrobial agents are available; however, it is crucial that the selected agent exhibits a broad spectrum of activity and is not susceptible to promoting resistance. Additionally, future research should focus on the potential effect of antimicrobial gloves on the skin microbiota and irritation during extended wear. Careful integration of the antimicrobial agent is essential to ensure optimal effectiveness without compromising the mechanical properties of the gloves.
  18. Lee KK, Low DYS, Foo ML, Yu LJ, Choong TSY, Tang SY, et al.
    Polymers (Basel), 2021 Feb 23;13(4).
    PMID: 33672331 DOI: 10.3390/polym13040668
    While the economy is rapidly expanding in most emerging countries, issues coupled with a higher population has created foreseeable tension among food, water, and energy. It is crucial for more sustainable valorization of resources, for instance, nanocellulose, to address the core challenges in environmental sustainability. As the complexity of the system evolved, the timescale of project development has increased exponentially. However, research on the design and operation of integrated nanomaterials, along with energy supply, monitoring, and control infrastructure, has seriously lagged. The development cost of new materials can be significantly reduced by utilizing molecular simulation technology in the design of nanostructured materials. To realize its potential, nanocellulose, an amphiphilic biopolymer with the presence of rich -OH and -CH structural groups, was investigated via molecular dynamics simulation to reveal its full potential as Pickering emulsion stabilizer at the molecular level. This work has successfully quantified the Pickering stabilization mechanism profiles by nanocellulose, and the phenomenon could be visualized in three stages, namely the initial homogenous phase, rapid formation of micelles and coalescence, and lastly the thermodynamic equilibrium of the system. It was also observed that the high bead order was always coupled with a high volume of phase separation activities, through a coarse-grained model within 20,000 time steps. The outcome of this work would be helpful to provide an important perspective for the future design and development of nanocellulose-based emulsion products, which cater for food, cosmeceutical, and pharmaceutical industries.
  19. Lawrencia D, Wong SK, Low DYS, Goh BH, Goh JK, Ruktanonchai UR, et al.
    Plants (Basel), 2021 Jan 26;10(2).
    PMID: 33530608 DOI: 10.3390/plants10020238
    Rising world population is expected to increase the demand for nitrogen fertilizers to improve crop yield and ensure food security. With existing challenges on low nutrient use efficiency (NUE) of urea and its environmental concerns, controlled release fertilizers (CRFs) have become a potential solution by formulating them to synchronize nutrient release according to the requirement of plants. However, the most significant challenge that persists is the "tailing" effect, which reduces the economic benefits in terms of maximum fertilizer utilization. High materials cost is also a significant obstacle restraining the widespread application of CRF in agriculture. The first part of this review covers issues related to the application of conventional fertilizer and CRFs in general. In the subsequent sections, different raw materials utilized to form CRFs, focusing on inorganic and organic materials and synthetic and natural polymers alongside their physical and chemical preparation methods, are compared. Important factors affecting rate of release, mechanism of release and mathematical modelling approaches to predict nutrient release are also discussed. This review aims to provide a better overview of the developments regarding CRFs in the past ten years, and trends are identified and analyzed to provide an insight for future works in the field of agriculture.
  20. Mahendra CK, Abidin SAZ, Htar TT, Chuah LH, Khan SU, Ming LC, et al.
    Molecules, 2021 Apr 01;26(7).
    PMID: 33916053 DOI: 10.3390/molecules26072000
    In this day and age, the expectation of cosmetic products to effectively slow down skin photoaging is constantly increasing. However, the detrimental effects of UVB on the skin are not easy to tackle as UVB dysregulates a wide range of molecular changes on the cellular level. In our research, irradiated keratinocyte cells not only experienced a compromise in their redox system, but processes from RNA translation to protein synthesis and folding were also affected. Aside from this, proteins involved in various other processes like DNA repair and maintenance, glycolysis, cell growth, proliferation, and migration were affected while the cells approached imminent cell death. Additionally, the collagen degradation pathway was also activated by UVB irradiation through the upregulation of inflammatory and collagen degrading markers. Nevertheless, with the treatment of Swietenia macrophylla (S. macrophylla) seed extract and fractions, the dysregulation of many genes and proteins by UVB was reversed. The reversal effects were particularly promising with the S. macrophylla hexane fraction (SMHF) and S. macrophylla ethyl acetate fraction (SMEAF). SMHF was able to oppose the detrimental effects of UVB in several different processes such as the redox system, DNA repair and maintenance, RNA transcription to translation, protein maintenance and synthesis, cell growth, migration and proliferation, and cell glycolysis, while SMEAF successfully suppressed markers related to skin inflammation, collagen degradation, and cell apoptosis. Thus, in summary, our research not only provided a deeper insight into the molecular changes within irradiated keratinocytes, but also serves as a model platform for future cosmetic research to build upon. Subsequently, both SMHF and SMEAF also displayed potential photoprotective properties that warrant further fractionation and in vivo clinical trials to investigate and obtain potential novel bioactive compounds against photoaging.
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