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  1. Fulltext Kinetics Study of Microwave-Assisted Brine Extraction of Lipid from the Microalgae Nannochloropsis sp
    Zghaibi N, Omar R, Kamal SMM, Biak DRA, Harun R
    Molecules, 2020 Feb 12;25(4).
    PMID: 32059440 DOI: 10.3390/molecules25040784
    The kinetics of lipid extraction utilizing microwave-assisted extraction (MAE) from Nannochloropsis sp. microalgae were studied using a low cost and green solvent, namely brine (NaCl) solution. The kinetic modelling of the lipid extraction was performed to evaluate the mechanism of the lipid mass transfer using different extraction models, including Fick's Law, First and Second-order Rate Law and the Patricelli mathematical model. The Patricelli mathematical model described the kinetics of lipid extraction well, with the highest average values of determination coefficient (R2 ≥ 0.952) and the lowest average values of mean relative percentage deviation (MRPD ≤ 8.666%). The lipid analysis indicated a positive influence of the microwave temperature and time on the quantity and quality of extracted lipids. SEM analysis of spent microalgae clearly shows an increase in the distorted cell with increase microwave temperature and time, which could be directly correlated to the mechanism of the MAE-brine technique.
    Matched MeSH terms: Lipids/chemistry*; Salts/chemistry*; Microalgae/chemistry*
  2. Alginate graft copolymers and alginate-co-excipient physical mixture in oral drug delivery
    Wong TW
    J Pharm Pharmacol, 2011 Dec;63(12):1497-512.
    PMID: 22060280 DOI: 10.1111/j.2042-7158.2011.01347.x
    Use of alginate graft copolymers in oral drug delivery reduces dosage form manufacture complexity with reference to mixing or coating processes. It is deemed to give constant or approximately steady weight ratio of alginate to covalently attached co-excipient in copolymers, thereby leading to controllable matrix processing and drug release. This review describes various grafting approaches and their outcome on oral drug release behaviour of alginate graft copolymeric matrices. It examines drug release modulation mechanism of alginate graft copolymers against that of co-excipients in non-grafted formulations.
    Matched MeSH terms: Alginates/chemistry*; Chemistry, Pharmaceutical; Excipients/chemistry*
  3. Protective potential of cerium oxide nanoparticles in diabetes mellitus
    Chai WF, Tang KS
    J Trace Elem Med Biol, 2021 Jul;66:126742.
    PMID: 33773280 DOI: 10.1016/j.jtemb.2021.126742
    BACKGROUND: Diabetes mellitus (DM) is a non-communicable metabolic disease which is closely related to excessive oxidative stress after constant exposure to high plasma glucose. Although the current antidiabetic medications are effective in lowering blood glucose, these medications do not prevent or reverse the disease progression. Thus, there is a crucial need to explore new therapeutic interventions that could address this shortcoming. As cerium oxide nanoparticles (CONPs) possess antioxidant property, this agent may be used as a treatment option for the management of DM.

    PURPOSE: This review aims to provide a critical evaluation of the pharmacological and antidiabetic effects of CONPs in cell and animal models. The roles of CONPs in attenuating DM complications are also presented in this report.

    METHODS: We conducted a literature search in the PubMed database using the keywords "cerium oxide", "cerous oxide", "ceria", "nanoceria", and "diabetes" from inception to December 2020. The inclusion criteria were primary source articles that investigated the role of CONPs in DM and diabetic complications.

    RESULTS: We identified 47 articles from the initial search. After the thorough screening, only 31 articles were included in this study. We found that CONPs can attenuate parameters that are related to DM and diabetic complications in various animals and cell culture models.

    CONCLUSION: CONPs could potentially be used in the treatment of those with DM and complications caused by the disease.

    Matched MeSH terms: Cerium/chemistry; Protective Agents/chemistry; Nanoparticles/chemistry*
  4. Fulltext Botanical Origin Differentiation of Malaysian Stingless Bee Honey Produced by Heterotrigona itama and Geniotrigona thoracica Using Chemometrics
    Ng WJ, Sit NW, Ooi PA, Ee KY, Lim TM
    Molecules, 2021 Dec 16;26(24).
    PMID: 34946710 DOI: 10.3390/molecules26247628
    Stingless bee honey, specifically honeydew honey, is generally valued for its better health benefits than those of most blossom types. However, scientific studies about the differentiation of stingless bee honey based on honeydew and blossom origins are very limited. In this study, 13C NMR spectroscopy was employed to quantify the seven major sugar tautomers in stingless bee honey samples, and the major sugar compositions of both honeydew and blossom types were found not significantly different. However, several physicochemical properties of honeydew honey including moisture content, free acidity, electrical conductivity, ash content, acetic acid, diastase, hydrogen peroxide, and mineral elements levels were significantly higher; while total soluble solid, proline, and hydroxymethylfurfural were significantly lower than blossom honey. Greater antioxidant capacity in honeydew honey was proven with higher total phenolic compounds, ABTS, DPPH, superoxide radical scavenging activities, peroxyl radical inhibition, iron chelation, and ferric reducing power. Using principal component analysis (PCA), two clusters of stingless bee honey from the honeydew and blossom origin were observed. PCA also revealed that the differentiation between honeydew and blossom origin of stingless bee honey is possible with certain physicochemical and antioxidant parameters. The combination of NMR spectroscopy and chemometrics are suggested to be useful to determine the authenticity and botanical origin of stingless bee honey.
    Matched MeSH terms: Antioxidants/chemistry*; Carbohydrates/chemistry*; Phenols/chemistry*
  5. Fulltext Malaysian researchers bet big on home-grown Viagra
    Cyranoski D
    Nat Med, 2005 Sep;11(9):912.
    PMID: 16145563 DOI: 10.1038/nm0905-912a
    Matched MeSH terms: Aphrodisiacs/chemistry; Plant Extracts/chemistry; Eurycoma/chemistry*
  6. Fulltext Variations in Antioxidant Capacity, Oxidative Stability, and Physicochemical Quality Parameters of Walnut (Juglans regia) Oil with Roasting and Accelerated Storage Conditions
    Elouafy Y, El Idrissi ZL, El Yadini A, Harhar H, Alshahrani MM, Al Awadh AA, et al.
    Molecules, 2022 Nov 09;27(22).
    PMID: 36431794 DOI: 10.3390/molecules27227693
    Walnut oil, like all vegetable oils, is chemically unstable because of the sensitivity of its unsaturated fatty acids to the oxidation phenomenon. This phenomenon is based on a succession of chemical reactions, under the influence of temperature or storage conditions, that always lead to a considerable change in the quality of the oil by promoting the oxidation of unsaturated fatty acids through the degradation of their C-C double bonds, leading to the formation of secondary oxidation products that reduce the nutritional values of the oil. This research examines the oxidative stability of roasted and unroasted cold-pressed walnut oils under accelerated storage conditions. The oxidative stability of both oils was evaluated using physicochemical parameters: chemical composition (fatty acids, phytosterols, and tocopherols), pigment content (chlorophyll and carotenoids), specific extinction coefficients (K232 and K270), and quality indicators (acid and peroxide value) as well as the evaluation of radical scavenging activity by the DPPH method. The changes in these parameters were evaluated within 60 days at 60 ± 2 °C. The results showed that the levels of total phytosterols, the parameters of the acid and peroxide value, K232 and K270, increased slightly for both oils as well as the total tocopherol content and the antioxidant activity affected by the roasting process. In contrast, the fatty acid profiles did not change considerably during the 60 days of our study. After two months of oil treatment at 60 °C, the studied oils still showed an excellent physicochemical profile, which allows us to conclude that these oils are stable and can withstand such conditions. This may be due to the considerable content of tocopherols (vitamin E), which acts as an antioxidant.
    Matched MeSH terms: Antioxidants/chemistry; Fatty Acids/chemistry; Plant Oils/chemistry
  7. Fulltext Green photosensitisers for the degradation of selected pesticides of high risk in most susceptible food: A safer approach
    Baig A, Zubair M, Sumrra SH, Rashid U, Zafar MN, Ahmad F, et al.
    PLoS One, 2021;16(10):e0258864.
    PMID: 34710164 DOI: 10.1371/journal.pone.0258864
    Pesticides are the leading defence against pests, but their unsafe use reciprocates the pesticide residues in highly susceptible food and is becoming a serious risk for human health. In this study, mint extract and riboflavin were tested as photosensitisers in combination with light irradiation of different frequencies, employed for various time intervals to improve the photo-degradation of deltamethrin (DM) and lambda cyhalothrin (λ-CHT) in cauliflower. Different source of light was studied, either in ultraviolet range (UV-C, 254 nm or UV-A, 320-380 nm) or sunlight simulator (> 380-800 nm). The degradation of the pesticides varied depending on the type of photosensitiser and light source. Photo-degradation of the DM and λ-CHT was enhanced by applying the mint extracts and riboflavin and a more significant degradation was achieved with UV-C than with either UV-A or sunlight, reaching a maximum decrement of the concentration by 67-76%. The light treatments did not significantly affect the in-vitro antioxidant activity of the natural antioxidants in cauliflower. A calculated dietary risk assessment revealed that obvious dietary health hazards of DM and λ-CHT pesticides when sprayed on cauliflower for pest control. The use of green chemical photosensitisers (mint extract and riboflavin) in combination with UV light irradiation represents a novel, sustainable, and safe approach to pesticide reduction in produce.
    Matched MeSH terms: Nitriles/chemistry*; Pesticides/chemistry*; Pyrethrins/chemistry*
  8. Cardiovascular Protective Effects of Centella asiatica and Its Triterpenes: A Review
    Razali NNM, Ng CT, Fong LY
    Planta Med, 2019 Nov;85(16):1203-1215.
    PMID: 31539918 DOI: 10.1055/a-1008-6138
    Centella asiatica, a triterpene-rich medicinal herb, is traditionally used to treat various types of diseases including neurological, dermatological, and metabolic diseases. A few articles have previously reviewed a broad range of pharmacological activities of C. asiatica, but none of these reviews focuses on the use of C. asiatica in cardiovascular diseases. This review aims to summarize recent findings on protective effects of C. asiatica and its active constituents (asiatic acid, asiaticoside, madecassic acid, and madecassoside) in cardiovascular diseases. In addition, their beneficial effects on conditions associated with cardiovascular diseases were also reviewed. Articles were retrieved from electronic databases such as PubMed and Google Scholar using keywords "Centella asiatica," "asiatic acid," "asiaticoside," "madecassic acid," and "madecassoside." The articles published between 2004 and 2018 that are related to the aforementioned topics were selected. A few clinical studies published beyond this period were also included. The results showed that C. asiatica and its active compounds possess potential therapeutic effects in cardiovascular diseases and cardiovascular disease-related conditions, as evidenced by numerous in silico, in vitro, in vivo, and clinical studies. C. asiatica and its triterpenes have been reported to exhibit cardioprotective, anti-atherosclerotic, antihypertensive, antihyperlipidemic, antidiabetic, antioxidant, and anti-inflammatory activities. In conclusion, more clinical and pharmacokinetic studies are needed to support the use of C. asiatica and its triterpenes as therapeutic agents for cardiovascular diseases. Besides, elucidation of the molecular pathways modulated by C. asiatica and its active constituents will help to understand the mechanisms underlying the cardioprotective action of C. asiatica.
    Matched MeSH terms: Triterpenes/chemistry; Centella/chemistry*; Pentacyclic Triterpenes/chemistry
  9. [Ionic liquid based ultrasonication-assisted extraction of essential oil from the leaves of Persicaria minor and conductor-like screening model for realistic solvents study]
    Habib U, Cecilia DW, Maizatul SS
    Se Pu, 2017 Jun 08;35(6):656-664.
    PMID: 29048794 DOI: 10.3724/SP.J.1123.2017.02002
    Ionic liquids (ILs) based ultrasonic-assisted extract has been applied for the extraction of essential oil from Persicaria minor leaves. The effects of temperature, sonication time, and particle size of the plant material on the yield of essential oil were investigated. Among the different ILs employed, 1-ethyl-3-methylimidazolium acetate was the most effective, providing a 9.55% yield of the essential oil under optimum conditions (70 ℃, 25 min, IL:hexane ratio of 7:10 (v/v), particle size 60-80 mesh). The performance of 1-ethyl-3-methylimidazolium acetate in the extraction was attributed to its low viscosity and ability to disintegrate the structural matrix of the plant material. The ability of 1-ethyl-3-methylimidazolium acetate was also confirmed using the conductor like-screening model for realistic solvents. This research proves that ILs can be used to extract essential oils from lignocellulosic biomass.
    Matched MeSH terms: Plant Extracts/chemistry*; Plant Leaves/chemistry; Tracheobionta/chemistry*
  10. Phytosterols-induced viscoelasticity of oleogels prepared by using monoglycerides
    Bin Sintang MD, Danthine S, Brown A, Van de Walle D, Patel AR, Tavernier I, et al.
    Food Res Int, 2017 10;100(Pt 1):832-840.
    PMID: 28873756 DOI: 10.1016/j.foodres.2017.07.079
    Monoglycerides (MGs) and phytosterols (PS) are known to form firm oleogels with liquid oil. However, the oleogels are prone to undergo polymorphic transition over time that lead to crystals' aggregation thus, compromises physical properties. Thus, we combined MGs with PS to control the crystallization and modify the morphology of the combination oleogels, as both components are reported to interact together. The oleogels were prepared at different ratio combinations and characterized in their rheological, thermal, morphology, and diffraction properties. The results showed that the 8:2 MGP:PS exhibited higher storage modulus (G') than the MGP mono-component. The combination oleogels exhibited effects on the crystallization and polymorphic transition. Consequently, the effects led to change in the morphology of the combination oleogels which was visualized using optical and electron microscope. The resultant effect on the morphology is associated with crystal defect. Due to observable crystals of MGP and PS, it is speculated that the combination oleogels formed a mixed crystal system. This was confirmed with diffraction analysis in which the corresponding peaks from MGP and PS were observed in the combination oleogels. However, the 8:2 oleogel exhibited additional peak at 35.41Å. Ultimately, the 8:2 was the optimum combination observed in our study. Interestingly, this combination is inspired by nature as sterols (phytosterols) are natural component of lipid membrane whilst MGP has properties similar to phospholipids. Hence, the results of our study not only beneficial for oil structuring, but also for the fields of biophysical and pharmaceutical.
    Matched MeSH terms: Organic Chemicals/chemistry; Phytosterols/chemistry*; Monoglycerides/chemistry*
  11. Pharmacokinetic and Pharmacodynamic Features of Nanoemulsion Following Oral, Intravenous, Topical and Nasal Route
    Choudhury H, Gorain B, Chatterjee B, Mandal UK, Sengupta P, Tekade RK
    Curr Pharm Des, 2017;23(17):2504-2531.
    PMID: 27908273 DOI: 10.2174/1381612822666161201143600
    BACKGROUND: Most of the active pharmaceutical ingredients discovered recently in pharmaceutical field exhibits poor aqueous solubility that pose major problem in their oral administration. The oral administration of these drugs gets further complicated due to their short bioavailability, inconsistent absorption and inter/intra subject variability.

    METHODS: Pharmaceutical emulsion holds a significant place as a primary choice of oral drug delivery system for lipophilic drugs used in pediatric and geriatric patients. Pharmacokinetic studies on nanoemulsion mediated drugs delivery approach indicates practical feasibility in regards to their clinical translation and commercialization.

    RESULTS: This review article is to provide an updated understanding on pharmacokinetic and pharmacodynamic features of nanoemulsion delivered via oral, intravenous, topical and nasal route.

    CONCLUSION: The article is of huge interest to formulation scientists working on range of lipophilic drug molecules intended to be administered through oral, intravenous, topical and nasal routes for vivid medical benefits.

    Matched MeSH terms: Pharmaceutical Preparations/chemistry*; Emulsions/chemistry*; Nanostructures/chemistry*
  12. In situ forming phase-inversion implants for sustained ocular delivery of triamcinolone acetonide
    Sheshala R, Hong GC, Yee WP, Meka VS, Thakur RRS
    Drug Deliv Transl Res, 2019 04;9(2):534-542.
    PMID: 29484530 DOI: 10.1007/s13346-018-0491-y
    The objectives of this study were to develop biodegradable poly-lactic-co-glycolic acid (PLGA) based injectable phase inversion in situ forming system for sustained delivery of triamcinolone acetonide (TA) and to conduct physicochemical characterisation including in vitro drug release of the prepared formulations. TA (at 0.5%, 1% and 2.5% w/w loading) was dissolved in N-methyl-2-pyrrolidone (NMP) solvent and then incorporated 30% w/w PLGA (50/50 and 75/25) polymer to prepare homogenous injectable solution. The formulations were evaluated for rheological behaviour using rheometer, syringeability by texture analyser, water uptake and rate of implant formation by optical coherence tomography (OCT) microscope. Phase inversion in situ forming formulations were injected into PBS pH 7.3 to form an implant and release samples were collected and analysed for drug content using a HPLC method. All formulations exhibited good syringeability and rheological properties (viscosity: 0.19-3.06 Pa.s) by showing shear thinning behaviour which enable them to remain as free-flowing solution for ease administration. The results from OCT microscope demonstrated that thickness of the implants were increased with the increase in time and the rate of implant formation indicated the fast phase inversion. The drug release from implants was sustained over a period of 42 days. The research findings demonstrated that PLGA/NMP-based phase inversion in situ forming implants can improve compliance in patient's suffering from ocular diseases by sustaining the drug release for a prolonged period of time and thereby reducing the frequency of ocular injections.
    Matched MeSH terms: Glucocorticoids/chemistry*; Pyrrolidinones/chemistry*; Triamcinolone Acetonide/chemistry*
  13. Engineered Hydrogels in Cancer Therapy and Diagnosis
    Sepantafar M, Maheronnaghsh R, Mohammadi H, Radmanesh F, Hasani-Sadrabadi MM, Ebrahimi M, et al.
    Trends Biotechnol, 2017 11;35(11):1074-1087.
    PMID: 28734545 DOI: 10.1016/j.tibtech.2017.06.015
    Over the last decade, numerous investigations have attempted to clarify the intricacies of tumor development to propose effective approaches for cancer treatment. Thanks to the unique properties of hydrogels, researchers have made significant progress in tumor model reconstruction, tumor diagnosis, and associated therapies. Notably, hydrogel-based systems can be adjusted to respond to cancer-specific hallmarks and/or external stimuli. These well-known drug reservoirs can be used as smart carriers for multiple cargos, including both naked and nanoparticle-encapsulated chemotherapeutics, genes, and radioisotopes. Recent works have attempted to specialize hydrogels for cancer research; we comprehensively review this topic for the first time, synthesizing past results and defining paths for future work.
    Matched MeSH terms: Drug Carriers/chemistry; Hydrogels/chemistry; Nanoparticles/chemistry
  14. Synthesis, Characterization and DNA-Binding Studies of Hydroxyl Functionalized Platinum(II) Salphen Complexes
    Mohd Sukri SA, Heng LY, Abd Karim NH
    J Fluoresc, 2017 May;27(3):1009-1023.
    PMID: 28224358 DOI: 10.1007/s10895-017-2035-0
    The platinum(II) salphen complex N,N'-Bis-4-(hydroxysalicylidene)-phenylenediamine-platinum(II); (1) and its two derivatives containing hydroxyl functionalized side chains N,N'-bis-[4-[[1-(2-hydroxyethoxy)] salicylidene] phenylenediamine-platinum(II); (2) and N,N'-bis-[4-[[1-(3-hydroxypropoxy)] salicylidene] phenylenediamine-platinum(II); (3) were synthesized and characterized. The structures of the complexes were confirmed by 1H and 13C NMR spectroscopy, FTIR, ESI-MS and CHN elemental analyses. The effects of the hydroxyl substituent on the spectral properties and the DNA binding behaviors of the Pt(II) complexes were explored. The binding mode and interactions of these complexes with duplex DNA (calf thymus DNA and porcine DNA) and also single-stranded DNA were studied by UV-Vis and emission DNA titration. The complexes interact with DNA by intercalation binding mode with the binding constants in the order of magnitude (Kb = 104 M-1, CT-DNA) and (Kb = 105 M-1, porcine DNA). The intercalation of the complex in the DNA structure was proposed to happen by π-π stacking due to its square-planar geometry and aromatic rings structure. The phosphorescence emission spectral characteristics of Pt(II) complexes when interacted with DNA have been studied. Also, the application of the chosen hydroxypropoxy side chains complex (3) as an optical DNA biosensor, specifically for porcine DNA was investigated. These findings will be valuable for the potential use of the platinum(II) salphen complex as an optical DNA biosensor for the detection of porcine DNA in food products.
    Matched MeSH terms: Phenylenediamines/chemistry*; Platinum/chemistry*; Coordination Complexes/chemistry*
  15. Recent Advances in Non-Invasive Delivery of Macromolecules using Nanoparticulate Carriers System
    Shadab M, Haque S, Sheshala R, Meng LW, Meka VS, Ali J
    Curr Pharm Des, 2017;23(3):440-453.
    PMID: 27784250 DOI: 10.2174/1381612822666161026163201
    BACKGROUND: The drug delivery of macromolecules such as proteins and peptides has become an important area of research and represents the fastest expanding share of the market for human medicines. The most common method for delivering macromolecules is parenterally. However parenteral administration of some therapeutic macromolecules has not been effective because of their rapid clearance from the body. As a result, most macromolecules are only therapeutically useful after multiple injections, which causes poor compliance and systemic side effects.

    METHOD: Therefore, there is a need to improve delivery of therapeutic macromolecules to enable non-invasive delivery routes, less frequent dosing through controlled-release drug delivery, and improved drug targeting to increase efficacy and reduce side effects.

    RESULT: Non-invasive administration routes such as intranasal, pulmonary, transdermal, ocular and oral delivery have been attempted intensively by formulating macromolecules into nanoparticulate carriers system such as polymeric and lipidic nanoparticles.

    CONCLUSION: This review discusses barriers to drug delivery and current formulation technologies to overcome the unfavorable properties of macromolecules via non-invasive delivery (mainly intranasal, pulmonary, transdermal oral and ocular) with a focus on nanoparticulate carrier systems. This review also provided a summary and discussion of recent data on non-invasive delivery of macromolecules using nanoparticulate formulations.

    Matched MeSH terms: Drug Carriers/chemistry; Macromolecular Substances/chemistry; Nanoparticles/chemistry*
  16. Fulltext Effects of Ultrasound Assisted Extraction in Conjugation with Aid of Actinidin on the Molecular and Physicochemical Properties of Bovine Hide Gelatin
    Ahmad T, Ismail A, Ahmad SA, Khalil KA, Leo TK, Awad EA, et al.
    Molecules, 2018 Mar 22;23(4).
    PMID: 29565325 DOI: 10.3390/molecules23040730
    Actinidin was used to pretreat the bovine hide and ultrasonic wave (53 kHz and 500 W) was used for the time durations of 2, 4 and 6 h at 60 °C to extract gelatin samples (UA2, UA4 and UA6, respectively). Control (UAC) gelatin was extracted using ultrasound for 6 h at 60 °C without enzyme pretreatment. There was significant (p < 0.05) increase in gelatin yield as the time duration of ultrasound treatment increased with UA6 giving the highest yield of 19.65%. Gel strength and viscosity of UAC and UA6 extracted gelatin samples were 627.53 and 502.16 g and 16.33 and 15.60 mPa.s, respectively. Longer duration of ultrasound treatment increased amino acids content of the extracted gelatin and UAC exhibited the highest content of amino acids. Progressive degradation of polypeptide chains was observed in the protein pattern of the extracted gelatin as the time duration of ultrasound extraction increased. Fourier transform infrared (FTIR) spectroscopy depicted loss of molecular order and degradation in UA6. Scanning electron microscopy (SEM) revealed protein aggregation and network formation in the gelatin samples with increasing time of ultrasound treatment. The study indicated that ultrasound assisted gelatin extraction using actinidin exhibited high yield with good quality gelatin.
    Matched MeSH terms: Cysteine Endopeptidases/chemistry*; Gelatin/chemistry; Peptides/chemistry
  17. Cellulose hydrogel development from unbleached oil palm biomass pulps for dermal drug delivery
    Wong LC, Poh JH, Tan WT, Khor BK, Murugaiyah V, Leh CP, et al.
    Int J Biol Macromol, 2023 Jan 01;224:483-495.
    PMID: 36273545 DOI: 10.1016/j.ijbiomac.2022.10.138
    Hydrogels are an attractive platform for drug delivery to the skin. Current cellulose hydrogel developments commonly focus on readily available bleached woody cellulose. Considering the detrimental environmental impacts of bleaching reagents, unbleached non-woody biomass was proposed as an alternative. Herein, this study aims to develop hydrogel from native cellulose extracted from oil palm empty fruit bunches for dermal drug delivery with an emphasis on evaluating the effect of alkali solvent compositions on hydrogel formation. Unbleached dissolving pulps were solubilized in alkali solvents containing sodium hydroxide (NaOH) (6-8%w/v) and urea (4-6%w/v) before crosslinking. Hydrogels were loaded with ibuprofen for skin permeation studies. Light brownish hydrogels formed are aesthetically acceptable and biodegradable with low cytotoxicity. NaOH content has a dominant role over urea where thinner and deformable crosslinked network walls in a porous hydrogel structure are associated with high NaOH content. Synergistic effects (cellulose solubility: 94 %; swelling ratio: ~2800 %) were observed at 7%w/v NaOH and 4%w/v urea with low toxicity. Most hydrogels showed >80 % of ibuprofen permeated into the skin and this increased with the swelling ratio of hydrogels. Unbleached cellulose pulps have excellent potential for hydrogel fabrication with outstanding physicomechanical properties for dermal drug delivery.
    Matched MeSH terms: Cellulose/chemistry; Sodium Hydroxide/chemistry; Urea/chemistry
  18. Morphinan Alkaloids from the Leaves of Alphonsea cylindrica and Their Antibacterial Properties
    Cho KH, Tan SP, Tan HY, Liew SY, Nafiah MA
    Planta Med, 2023 Jan;89(1):79-85.
    PMID: 35288885 DOI: 10.1055/a-1797-0548
    A phytochemical study has been carried out on CH2Cl2 extract of Alphonsea cylindrica leaves, resulting in the isolation of three new morphinan alkaloids. They are kinomenine (1: ), N-methylkinomenine (2: ), and hydroxymethylkinomenine (3: ). The structures of these compounds were elucidated by extensive spectroscopic analysis (1D and 2D NMR, IR, UV, HRESIMS) and comparison with the data reported in literature for similar alkaloids. Kinomenine (1: ) and N-methylkinomenine (2: ) showed weak inhibition against S. aureus (MIC values of 1: and 2:  = 500 µg/mL; pIC50 values in 95% C. I. of: 1:  = 2.9 to 3.0; 2:  = 2.9 to 3.1), while kinomenine (1: ) also showed weak inhibition against E. coli (MIC values of 1:  = 500 µg/mL; pIC50 value in 95% C. I. of: 1:  = 2.9) by broth microdilution method. The results obtained can be used as future referencefor the discovery of morphinans and the potential of A. cylindrica as an antibacterial source.
    Matched MeSH terms: Anti-Bacterial Agents/chemistry; Plant Extracts/chemistry; Plant Leaves/chemistry
  19. Anticariogenic and Mechanical Characteristics of Resin-Modified Glass Ionomer Cement Containing Lignin-Decorated Zinc Oxide Nanoparticles
    Malik Z, Muhammad N, Kaleem M, Nayyar M, Qazi AS, Butt DQ, et al.
    ACS Appl Bio Mater, 2023 Feb 20;6(2):425-435.
    PMID: 36700919 DOI: 10.1021/acsabm.2c00644
    This study aims to synthesize and characterize lignin-decorated zinc oxide nanoparticles before incorporating them into resin-modified glass ionomer cement (RMGIC) to improve their anticariogenic potential and mechanical properties (shear bond strength and microhardness). Probe sonication was used to synthesize lignin-decorated zinc oxide nanoparticles which were then characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Following characterization, these were incorporated in RMGIC (Gold label, Fuji II LC). Three major groups, experimental group A (EGA), experimental group B (EGB), and control group (CG), were outlined. EGA and EGB were divided into numbered subgroups based on the ascending concentrations of nanoparticles (5, 10, and 15%) of lignin-coated zinc oxide and zinc-oxide, respectively. CG served as a control and comprised cured RMGIC samples without any incorporation. Anticariogenic analysis was conducted on experimental RMGIC samples via disk-diffusion (n = 3) and direct contact test (n = 3) against Streptococcus mutans (ATCC 25175). Optical density values for days 1, 3, and 5 were recorded via a UV-Vis spectrophotometer. A shear bond strength test was performed using 35 premolars. The adhesive remnant index was used to estimate the site of bond failure. For the Vickers microhardness test (n = 3), 100 g of load at 10 s dwell time was set. Atomic absorption spectroscopy was performed over 28 days to determine the release of zinc from the samples. All tests were analyzed statistically. The anticariogenic potential of EGA and EGB was significantly greater (p ≤ 0.05) than that of the control. The shear bond strength test reported the highest value for EGA15 with all groups exhibiting failure at the bracket/RMGIC interface. The microhardness of EGA15 yielded the highest value (p ≤ 0.05). Release kinetics displayed a steady release with EGB15 exhibiting the highest value. The EGA and EGB samples displayed good anticariogenic potential, which was sustained for 28 days without any deleterious effect on the shear bond strength and microhardness.
    Matched MeSH terms: Composite Resins/chemistry; Glass Ionomer Cements/chemistry; Resin Cements/chemistry
  20. Fulltext Chemical composition, antioxidant, antimicrobial and antiviral activities of the leaf extracts of Syzygium myrtifolium
    Ahmad MA, Lim YH, Chan YS, Hsu CY, Wu TY, Sit NW
    Acta Pharm, 2022 Jun 01;72(2):317-328.
    PMID: 36651512 DOI: 10.2478/acph-2022-0013
    This study was conducted to evaluate the chemical composition and biological activities of the leaf extracts of Syzygium myrtifolium Walp. (Myrtaceae). The results indicate that the leaf extracts of S. myrtifolium contain various classes of phytochemicals (alkaloids, anthraquinones, flavonoids, phenolics, saponins, tannins and triterpenoids) and possess antioxidant, antibacterial, antifungal and antiviral activities. Ethyl acetate, ethanol, methanol, and water extracts exhibited significantly higher (p < 0.05) oxygen radical absorbance capacity and ferric-reducing antioxidant power than the hexane and chloroform extracts. However, all extracts exhibited stronger inhibitory activity against four tested species of yeasts (minimal inhibitory concentration: 0.02-0.31 mg mL-1) than against six tested species of bacteria (minimal inhibitory concentration: 0.16-1.25 mg mL-1). The ethanolic extract offered the highest protection of Vero cells (viability > 70 %) from the cytopathic effect caused by the Chikungunya virus while the ethyl acetate extract showed significant replication inhibitory activity against the virus (p < 0.001) using the replicon-enhanced green fluorescent protein reporter system.
    Matched MeSH terms: Ethanol/chemistry; Antioxidants/chemistry; Plant Extracts/chemistry
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