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  1. Mardziah CM, Sopyan I, Hamdi M, Ramesh S
    Med J Malaysia, 2008 Jul;63 Suppl A:79-80.
    PMID: 19024993
    Improvement of the mechanical properties of hydroxyapatite (HA) can be achieved by the incorporation of metal. In addition, incorporation of strontium ion into HA crystal structures has been proved effective to enhance biochemical properties of bone implant. In this research, strontium-doped HA powder was developed via a sol-gel method to produce extraordinarily fine strontium-doped HA (Sr-doped HA) powder. XRD measurement had shown that the powder contained hydroxyapatite phase only for all doping concentration except for 2%, showing that Sr atoms have suppressed the appearance of beta-TCP as the secondary phase. Morphological evaluation by FESEM measurement shows that the particles of the Sr-doped HA agglomerates are globular in shape with an average size of 1-2 microm in diameter while the primary particles have a diameter of 30-150 nm in average.
    Matched MeSH terms: Powders/chemistry
  2. Etti CJ, Yusof YA, Chin NL, Mohd Tahir S
    J Diet Suppl, 2017 Mar 04;14(2):132-145.
    PMID: 27487244
    The tableting properties of Labisia pumila herbal powder, which is well known for its therapeutic benefits was investigated. The herbal powder was compressed into tablets using a stainless steel cylindrical uniaxial die of 13-mm- diameter with compaction pressures ranging from 7 to 25 MPa. Two feed weights, 0.5 and 1.0 g were used to form tablets. Some empirical models were used to describe the compressibility behavior of Labisia pumila tablets. The strength and density of tablets increased with increase in compaction pressure and resulted in reduction in porosity of the tablets. Smaller feeds, higher forces and increase in compaction pressure, contributed to more coherent tablets. These findings can be used to enhance the approach and understanding of tableting properties of Labisia pumila herbal powder tablets.
    Matched MeSH terms: Powders/chemistry*
  3. Phing PL, Abdullah A, Sin CL, Foong SCY
    Acta Sci Pol Technol Aliment, 2022 2 18;21(1):111-122.
    PMID: 35174693 DOI: 10.17306/J.AFS.0901
    BACKGROUND: Bintangor oranges are a mandarin species that is abundant in vitamin C and beta-carotene. However, due to its short shelf life, the fresh fruit can be converted into powder form, which is comparatively more stable.

    METHODS: This study compares the effects of spray drying, freeze drying, drum drying, vacuum oven drying, and convection oven drying on the physicochemical properties of Bintangor orange powder, including vitamin C and total carotenoid content. The physicochemical properties analyzed for the powders were color analysis, moisture content, water activity, hygroscopicity, degree of caking, wettability, flowability, water solubility index, and bulk density.

    RESULTS: Our results showed that freeze dried and convection oven dried powders retained their color so that the powder was the same as the original puree. All powders used in this showed an acceptable moisture content level, with a range of 2.11–2.31%. Spray dried and drum dried powders had the lowest value of moisture content and water activity. Moreover, spray dried powders showed the lowest value in hygroscopicity and bulk density and took the shortest time to wet the powder. The highest solubility and flowability properties were 12.99%, 0.39 g/mL, 18.39 s, 96.08%, and 19.17°, respectively. However, the freeze drying method retained the highest value for both nutritional pigments of vitamin C and total carotenoid content, 18.31 mg/g and 91.32 μg/g, respectively.

    CONCLUSIONS: Freeze drying is the most suitable drying method with favorable powder properties compared to spray drying, drum drying, vacuum oven drying and convection oven drying.

    Matched MeSH terms: Powders/chemistry
  4. Sopyan I, Rosli A, Raihana MF
    Med J Malaysia, 2008 Jul;63 Suppl A:81-2.
    PMID: 19024994
    A novel hydrothermal process has been developed various hydroxyapatite(HA) powder. The HA powder was investigated in different calcination temperatures over the range of 200 degrees C-800 degrees C. TG/DTA and XRD analysis revealed that at temperatures of 700-800 degrees C the decomposition processes and phase changes took place. It is due to the appearance of TCP phase substituting the HA phase. FESEM observation showed that the produced hydroxyapatite powder was extraordinarily fine with nanosize primary particles and almost evenly spherical in shaped. Its high purity proved that the powder fulfills medical requirement.
    Matched MeSH terms: Powders/chemistry
  5. Tan TC, AlKarkhi AF, Easa AM
    Food Chem, 2012 Oct 15;134(4):2430-6.
    PMID: 23442706 DOI: 10.1016/j.foodchem.2012.04.049
    The addition of ribose to bovine or porcine gelatine solutions followed by heating at 95 °C yielded brown solutions with different pH, colour (CIE L(*) and b(*)) and absorbance (A(420*) values. These differences were used for gelatine powder identification, differentiation and quality control. Differentiation analysis of the Maillard reaction parameters was conducted using cluster analysis (CA) and confidence intervals (CI). The potential use of the method as a quality control procedure was evaluated by using statistical process control (SPC). CA revealed that the two types of gelatine could be classified into two different groups. CI (95% confidence) revealed that the absorbance and colour values could be used as indicators for differentiation between the two types of gelatine because the intervals between the Maillard reaction parameters of the samples were far apart. The methodology demonstrated good reproducibility because it behaved predictably based on the X¯-S charts generated from the SPC charts.
    Matched MeSH terms: Powders/chemistry
  6. Krishna LS, Reddy AS, Zuhairi WY, Taha MR, Reddy AV
    ScientificWorldJournal, 2014;2014:184058.
    PMID: 25383360 DOI: 10.1155/2014/184058
    Indian jujuba seed powder (IJSP) has been investigated as a low-cost and an eco-friendly biosorbent, prepared for the removal of Acid Blue 25 (AB25) from aqueous solution. The prepared biomaterial was characterized by using FTIR and scanning electron microscopic studies. The effect of operation variables, such as IJSP dosage, contact time, concentration, pH, and temperature on the removal of AB25 was investigated, using batch biosorption technique. Removal efficiency increased with increase of IJSP dosage but decreased with increase of temperature. The equilibrium data were analyzed by the Langmuir and the Freundlich isotherm models. The data fitted well with the Langmuir model with a maximum biosorption capacity of 54.95 mg g(-1). The pseudo-second-order kinetics was the best for the biosorption of AB25 by IJSP, with good correlation. Thermodynamic parameters such as standard free energy change (ΔG(0)), standard enthalpy changes (ΔH(0)), and standard entropy changes (ΔS(0)) were analyzed. The removal of AB25 from aqueous solution by IJSP was a spontaneous and exothermic adsorption process. The results suggest that IJSP is a potential low-cost and an eco-friendly biosorbent for the AB25 removal from synthetic AB25 wastewater.
    Matched MeSH terms: Powders/chemistry
  7. Ramesh S, Tan CY, Aw KL, Yeo WH, Hamdi M, Sopyan I, et al.
    Med J Malaysia, 2008 Jul;63 Suppl A:89-90.
    PMID: 19024998
    The sintering behaviour of a commercial HA and synthesized HA was investigated over the temperature range of 700 degrees C to 1400 degrees C in terms of phase stability, bulk density, Young's modulus and Vickers hardness. In the present research, a wet chemical precipitation reaction was successfully employed to synthesize a submicron, highly crystalline, high purity and single phase stoichiometric HA powder that is highly sinteractive particularly at low temperature regimes below 1100 degrees C. It has been revealed that the sinterability of the synthesized HA was significantly greater than that of the commercial HA. The temperature for the onset of sintering and the temperature required to achieve densities above 98% of theoretical value were approximately 150 degrees C lower for the synthesized HA than the equivalent commercial HA. Nevertheless, decomposition of HA phase upon sintering was not observed in the present work for both powders.
    Matched MeSH terms: Powders/chemistry*
  8. Tan CY, Ramesh S, Aw KL, Yeo WH, Hamdi M, Sopyan I
    Med J Malaysia, 2008 Jul;63 Suppl A:87-8.
    PMID: 19024997
    The sintering behaviour of synthesized HA powder that was calcined at various temperatures ranging from 700 degrees C to 1000 degrees C was investigated in terms of phase stability, bulk density, Young's modulus and Vickers hardness. The calcination treatment resulted in higher crystallinity of the starting HA powder. Decomposition of HA phase to form secondary phases was not observed in all the calcined powders. The results also indicated that powder calcination (up to 900 degrees C) prior to sintering has negligible effect on the sinterability of the HA compacts. However, powder calcined at 1000 degrees C was found to be detrimental to the properties of sintered hydroxyapatite bioceramics.
    Matched MeSH terms: Powders/chemistry*
  9. Natasha AN, Sopyan I, Mel M, Ramesh S
    Med J Malaysia, 2008 Jul;63 Suppl A:85-6.
    PMID: 19024996
    The effect of Manganese (Mn) addition on the Vickers hardness and relative density of nanocrystalline hydroxyapatite (HA) dense bodies were studied. The starting Mn doped HA powders was synthesized via sol-gel method with Mn concentration varies from 2 mol% up to 15 mol% Mn. The Mn doped HA disc samples were prepared by uniaxial pressing at 200MPa and subsequently sintered at 1300 degrees C. Characterization was carried out where appropriate to determine the phases present, bulk density, Vickers hardness of the various content of Mn doped HA dense bodies. The addition of Mn was observed to influence the color appearance of the powders and dense bodies as well. Higher Mn concentration resulted in dark grey powders. It was also found that the hardness and relative density of the material increased as the Mn content increased and influenced by the crystallinity of the prepared Mn doped HA powders.
    Matched MeSH terms: Powders/chemistry*
  10. Brand-Miller J, Atkinson F, Rowan A
    Nutrients, 2013 Jan;5(1):23-31.
    PMID: 23306187 DOI: 10.3390/nu5010023
    Powdered milk products for children (Growing Up Milk Powders or GUMPs) containing added carbohydrates such as glucose and sucrose are now well established in parts of Asia. We surveyed GUMPs in Malaysia and Indonesia to determine the content of added carbohydrates. The ingredient lists and nutrition information panels were used to calculate the percentage of declared carbohydrates contributed by added carbohydrates and a subset of seven products was tested for their glycemic index (GI) and insulin responses in healthy adults. The glycemic load for each product was calculated. In total, 58 products (n = 24 in Malaysia and n = 34 in Indonesia) were surveyed. Added carbohydrate content (excluding fibre) ranged from 0 to 21.5 g per serve. Milk powders without added sources of carbohydrate had similar GI values to standard liquid whole milk. Products containing maltodextrins, corn or glucose syrups increased the GI by more than 2-fold, and glycemic load (GL) by 7-fold compared to milk powders with no added carbohydrates. Insulin responses were significantly but not strongly correlated with glucose responses (r = 0.32, p < 0.006). Children's milk powders containing higher levels of added carbohydrate ingredients elicit higher glucose and insulin responses than liquid or powdered whole milk.
    Matched MeSH terms: Powders/chemistry*
  11. Ghazali AR, Muralitharan RV, Soon CK, Salyam T, Ahmad Maulana NN, Mohamed Thaha UAB, et al.
    Asian Pac J Cancer Prev, 2020 Nov 01;21(11):3381-3386.
    PMID: 33247699 DOI: 10.31557/APJCP.2020.21.11.3381
    BACKGROUND: Traditional cooling rice powder (bedak sejuk) is a fermented rice-based cosmetic that is applied topically on one's skin, as an overnight facial mask. According to user testimonies, bedak sejuk beautifies and whitens skin, whereby these benefits could be utilised as a potential melanoma chemopreventive agent.

    OBJECTIVE: Hence, this study aimed to determine the effects of bedak sejuk made from Oryza sativa ssp. indica (Indica) and Oryza sativa ssp. japonica (Japonica) on UVB-induced B164A5 melanoma cells, and also identify the antioxidant capacities of both types of bedak sejuk.

    METHODS: The optimum dose of Indica and Japonica bedak sejuk to treat the cells was determined via the MTT assay. Then, the antioxidant capacities of both types of bedak sejuk were determined using the FRAP assay.

    RESULTS: From the MTT assay, it was found that Indica and Japonica bedak sejuk showed no cytotoxic effects towards the cells. Hence, no IC50 can be obtained and two of the higher doses, 50 and 100 g/L were chosen for treatment. In the FRAP assay, Indica bedak sejuk at 50 and 100 g/L showed FRAP values of 0.003 ± 0.001 μg AA (ascorbic acid)/g of bedak sejuk and 0.004 ± 0.0003 μg AA/g of bedak sejuk. Whereas Japonica bedak sejuk at 50 g/L had the same FRAP value as Indica bedak sejuk at 100 g/L. As for Japonica bedak sejuk at 100 g/L, it showed the highest antioxidant capacity with the FRAP value of 0.01 ± 0.0007 μg AA/g of bedak sejuk which was statistically significant (p < 0.05) when compared to other tested concentrations.

    CONCLUSION: In conclusion, Japonica bedak sejuk has a higher antioxidant capacity compared to Indica bedak sejuk despite both being not cytotoxic towards the cells. Regardless, further investigations need to be done before bedak sejuk could be developed as potential melanoma chemoprevention agents.

    Matched MeSH terms: Powders/chemistry
  12. Leung SSY, Parumasivam T, Nguyen A, Gengenbach T, Carter EA, Carrigy NB, et al.
    Eur J Pharm Biopharm, 2018 Jun;127:213-222.
    PMID: 29486303 DOI: 10.1016/j.ejpb.2018.02.033
    This study aimed to assess the robustness of using a spray drying approach and formulation design in producing inhalable phage powders. Two types of Pseudomonas phages, PEV2 (Podovirus) and PEV40 (Myovirus) in two formulations containing different amounts of trehalose (70% and 60%) and leucine (30% and 40%) were studied. Most of the surface of the produced powders was found to be covered in crystalline leucine. The powders were stored at 4 °C and 20 °C under vacuum. The phage stability and in vitro aerosol performance of the phage powders were examined on the day of production and after 1, 3 and 12 months of storage. A minor titer loss during production was observed for both phages (0.2-0.8 log10 pfu/ml). The storage stability of the produced phage powders was found to be phage and formulation dependent. No further reduction in titer occurred for PEV2 powders stored at 4 °C across the study. The formulation containing 30% leucine maintained the viability of PEV2 at 20 °C, while the formulation containing 40% leucine gradually lost titer over time with a storage reduction of ∼0.9 log10 pfu/ml measured after 12 months. In comparison, the PEV40 phage powders generally had a ∼ 0.5 log10 pfu/ml loss upon storage regardless of temperature. When aerosolized, the total in vitro lung doses of PEV2 were of the order of 107 pfu, except the formulation containing 40% leucine stored at 20 °C which had a lower lung dose. The PEV40 powders also had lung doses of 106-107 pfu. The results demonstrate that spray dried Myoviridae and Podoviridae phage in a simple formulation of leucine and trehalose can be successfully stored for one year at 4 °C and 20 °C with vacuum packaging.
    Matched MeSH terms: Powders/chemistry*
  13. Toibah AR, Sopyan I, Mel M
    Med J Malaysia, 2008 Jul;63 Suppl A:83-4.
    PMID: 19024995
    The incorporation of magnesium ions into the calcium phosphate structure is of great interest for the development of artificial bone implants. This paper investigates the preparation of magnesium-doped biphasic calcium phosphate (Mg-BCP) via sol gel method at various concentrations of added Mg. The effect of calcinations temperature (ranging from 500 degrees C to 900 degrees C) and concentrations of Mg incorporated into BCP has been studied by the aid of XRD, TGA and infrared spectroscopy (IR) in transmittance mode analysis. The study indicated that the powder was pure BCP and Mg-BCP with 100% purity and high crystallinity. The results also indicated that beta-tricalcium phosphate (beta-TCP) phase can be observed when the powder was calcined at 800 degrees C and above.
    Matched MeSH terms: Powders/chemistry*
  14. Noroozi M, Zakaria A, Radiman S, Abdul Wahab Z
    PLoS One, 2016;11(4):e0152699.
    PMID: 27064575 DOI: 10.1371/journal.pone.0152699
    In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.
    Matched MeSH terms: Powders/chemistry
  15. Erfanian A, Mirhosseini H, Rasti B, Hair-Bejo M, Bin Mustafa S, Abd Manap MY
    J Agric Food Chem, 2015 Jun 24;63(24):5795-804.
    PMID: 26022498 DOI: 10.1021/acs.jafc.5b01468
    The aim of this study was to evaluate the effects of fortification and nano-size reduction on calcium absorption and bioavailability of milk powder formula in sham, ovariectomized, and ovariectomized-osteoporosis rats as a menopause and menopause-osteoporosis model. Skim milk powder and skim milk powder fortified with calcium citrate and the suitable doses of inulin, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and vitamins D3, K1, and B6 were formulated based on the North American and Western European recommended dietary allowances. Optimization on cycle and pressure of high-pressure homogenizer was done to produce nano-fortified milk powder. In vivo study demonstrated that fortification and calcium citrate nano-fortified milk powder increased absorption and bioavailability of calcium, as well as bone stiffness and bone strength in sham, ovariectomized, and ovariectomized-osteoporosis rats. This study successfully developed an effective fortified milk powder for food application.
    Matched MeSH terms: Powders/chemistry
  16. Ng SH, Robert SD, Wan Ahmad WA, Wan Ishak WR
    Food Chem, 2017 Jul 15;227:358-368.
    PMID: 28274444 DOI: 10.1016/j.foodchem.2017.01.108
    The purpose of this study was to determine the effects of Pleurotus sajor-caju (PSC) powder addition at 0, 4, 8 and 12% levels on the nutritional values, pasting properties, thermal characteristics, microstructure, in vitro starch digestibility, in vivo glycaemic index (GI) and sensorial properties of biscuits. Elevated incorporation levels of PSC powder increased the dietary fibre (DF) content and reduced the pasting viscosities and starch gelatinisation enthalpy value of biscuits. The addition of DF-rich PSC powder also interfered with the integrity of the starch granules by reducing the sizes and inducing the uneven spherical shapes of the starch granules, which, in turn, resulted in reduced starch susceptibility to digestive enzymes. The restriction starch hydrolysis rate markedly reduced the GI of biscuits. The incorporation of 8% PSC powder in biscuits (GI=49) could be an effective way of developing a nutritious and low-GI biscuit without jeopardizing its desirable sensorial properties.
    Matched MeSH terms: Powders/chemistry
  17. Ramli MI, Sulong AB, Muhamad N, Muchtar A, Arifin A, Mohd Foudzi F, et al.
    PLoS One, 2018;13(10):e0206247.
    PMID: 30359433 DOI: 10.1371/journal.pone.0206247
    The combination of metallic bio-inert material, stainless-steel 316L (SS316L) and a bio-active material, hydroxyapatite (HA) can produce a composite which has superior properties for orthopaedic applications. The main objective of this study is to investigate the effects of sintering temperature and holding time on the physical and mechanical properties of the sintered part. 50wt.% SS316L and 50wt.% HA were mixed with a binder system of palm stearin (PS) and polyethylene (PE) at 61 vol.% powder loading. Rheological properties show a pseudo-plastic behaviour of the feedstock, where viscosity decreases with increasing shear rate. The feedstock was injection moulded into a tensile bar shape while thermal debinding was carried out at 320°C and 500°C. The brown parts were sintered at 1000, 1100, 1200 and 1300°C, with three different sintering times of 1, 3 and 5 hours in the furnace. It was found that the highest sintered density measured was 95.61% of the theoretical density. In addition, the highest hardness and Young's modulus measured were 150.45 HV and 52.61 GPa respectively, which are higher than those of human bone. The lowest percentage of carbon content was 0.022wt.% given by the sample sintered at 1300°C for 1 hour. Therefore, SS316L/HA composite with good mechanical and physical properties was successfully produced through the PIM process.
    Matched MeSH terms: Powders/chemistry
  18. Meka VS, Nali SR, Songa AS, Kolapalli VR
    AAPS PharmSciTech, 2012 Dec;13(4):1451-64.
    PMID: 23090110 DOI: 10.1208/s12249-012-9873-5
    The main objective of the present study is the physicochemical characterization of naturally available Terminalia catappa gum (Badam gum [BG]) as a novel pharmaceutical excipient and its suitability in the development of gastroretentive floating drug delivery systems (GRFDDS) to retard the drug for 12 h when the dosage form is exposed to gastrointestinal fluids in the gastric environment. As BG was being explored for the first time for its pharmaceutical application, physicochemical, microbiological, rheological, and stability studies were carried out on this gum. In the present investigation, the physicochemical properties, such as micromeritic, rheological, melting point, moisture content, pH, swelling index, water absorption, and volatile acidity, were evaluated. The gum was characterized by scanning electron microscopy, differential scanning calorimetry (DSC), powder X-ray diffraction studies (PXRD), and Fourier transform infrared spectroscopy (FTIR). Gastroretentive floating tablets of BG were prepared with the model drug propranolol HCl by direct compression methods. The prepared tablets were evaluated for all their physicochemical properties, in vitro buoyancy, in vitro drug release, and rate order kinetics. PBG 04 was selected as an optimized formulation based on its 12-h drug release and good buoyancy characteristics. The optimized formulation was characterized with FTIR, DSC, and PXRD studies, and no interaction between the drug and BG was found. Thus, the study confirmed that BG might be used in the gastroretentive drug delivery system as a release-retarding polymer.
    Matched MeSH terms: Powders/chemistry
  19. Mamat SS, Kamarolzaman MF, Yahya F, Mahmood ND, Shahril MS, Jakius KF, et al.
    PMID: 24267313 DOI: 10.1186/1472-6882-13-326
    Melastoma malabathricum L. (Melastomaceae) is a small shrub with various medicinal uses. The present study was carried out to determine the hepatoprotective activity of methanol extract of M. malabathricum leaves (MEMM) against the paracetamol-induced liver toxicity in rats model.
    Matched MeSH terms: Powders/chemistry
  20. Krishnamoorthy R, Govindan B, Banat F, Sagadevan V, Purushothaman M, Show PL
    J Biosci Bioeng, 2019 Jul;128(1):88-97.
    PMID: 30679113 DOI: 10.1016/j.jbiosc.2018.12.011
    Phosphoric acid impregnated activated carbon from date pits (DPAC) was prepared through single step activation. Prepared DPAC was studied for its structural, elemental, chemical, surface and crystal nature. Adsorption ability of the DPAC was assessed through divalent lead ions separation studies. Effect of adsorbent dosage, contact time, pH, operating temperature and initial feed concentration on lead removal by DPAC was studied. Maximum Pb(II) adsorption capacity of 101.35 mg/g was attained for a contact time of 30 min and pH of 6 at 30°C. Increase in initial feed concentration enhanced the adsorption ability of DPAC and the rise in adsorbent dosage resulted in improved Pb(II) removal efficiency. Thermodynamic studies revealed that the lead adsorption on DPAC was exothermic and instantaneous in nature. Kinetic and equilibrium studies confirmed the suitability of pseudo-second order and Langmuir isotherm for divalent lead ions binding on DPAC. Reusability studies showed that HCl was the effective regeneration medium and the DPAC could be reused for a maximum of 4 times with slight reduction in Pb(II) removal efficiency (<10%). Results indicated the promising use of date pits biomass as a low cost and efficient starting material to prepare activated carbon for divalent lead ions removal.
    Matched MeSH terms: Powders/chemistry
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