Displaying publications 41 - 60 of 89 in total

Abstract:
Sort:
  1. Effects of different drying methods on the antioxidant activities of leaves and berries of cayratia trifolia
    Rabeta MS, Lin S
    Sains Malaysiana, 2015;44:275-280.
    This study aimed to assess the effects of fresh, thermal drying method (vacuum oven drying), and nonthermal drying method (freeze drying) on the antioxidant activities of leaves and berries of Cayratia trifolia using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The total phenolic content (TPC) and flavonoid content (TFC) of the leaves and berries of C. trifolia were also measured. Based on the results obtained, the TPC, TFC, and antioxidant activities of the leaves and berries were arranged in the following order: freeze-dried sample with methanol extraction > vacuum-dried sample with methanol extraction > freeze-dried sample with water extraction > vacuum-dried sample with water extraction > fresh sample with methanol extraction > fresh sample with water extraction. The results showed a significant difference (p<0.05) between the fresh and dried samples. In conclusion, freeze drying was found to be a good method for maintaining TPC, TFC, and antioxidant activities by FRAP and DPPH methods in the leaves and berries of C. trifolia.
    Matched MeSH terms: Freeze Drying
  2. A shelf-stable fluorogenic isothermal amplification assay for the detection of Burkholderia pseudomallei
    Michelle Wong Tzeling J, Yean Yean C
    Analyst, 2016 Feb 21;141(4):1246-9.
    PMID: 26783560 DOI: 10.1039/c5an01741f
    A shelf-stable loop-mediated isothermal amplification (LAMP) reagent for Burkholderia pseudomallei detection is described. The coupling of LAMP reagents with the indirect colorimetric indicator and consequently its lyophilization enable the simple evaluation of results without the need for any advance laboratory instruments. The reagents were found to have a stable shelf life of at least 30 days with well-maintained sensitivity and specificity.
    Matched MeSH terms: Freeze Drying
  3. Fulltext Effect of drying method on functional properties and antioxidant activities of chicken skin gelatin hydrolysate
    Wan Omar WH, Sarbon NM
    J Food Sci Technol, 2016 Nov;53(11):3928-3938.
    PMID: 28035148 DOI: 10.1007/s13197-016-2379-5
    The aim of this study is to investigate the functional and antioxidant properties of chicken skin gelatin hydrolysate (CSGH) as affected by the drying method used in the preparation of gelatin (freeze-dried and vacuum dried). CSGH obtained from freeze-dried gelatin showed better functional properties such as emulsifying activity index (EAI), water holding and oil binding capacity at different pH compared to CSGH produced from vacuum dried gelatin. Meanwhile, the CSGH of the vacuum dried gelatin exhibited a better emulsifying stability index (ESI), foaming capacity and stability. CSGH from freeze-dried gelatin showed better antioxidant, DPPH radical scavenging and metal chelating activity.
    Matched MeSH terms: Freeze Drying
  4. Simvastatin-loaded lyophilized wafers as a potential dressing for chronic wounds
    Rezvanian M, Tan CK, Ng SF
    Drug Dev Ind Pharm, 2016 Dec;42(12):2055-2062.
    PMID: 27237190
    Wafers are an established drug delivery system for application to suppurating wounds. They can absorb wound exudates and are converted into a gel, offering a moist environment that is vital for wound healing. Simvastatin-loaded lyophilized wafers were developed using sodium carboxymethyl cellulose (CMC) and methyl cellulose (MC) and evaluated for their potential in the management of chronic wounds. Simvastatin (SIM) was chosen as the model drug since it is known to accelerate wound healing by promoting angiogenesis and lymphangiogenesis. Pre-formulation studies were carried out with CMC, MC, and a mixture of CMC and MC. Wafers obtained from aqueous gels of 3% CMC and blend of CMC-MC in the % weight ratio of 2:1 and 1.5:1.5 were selected for further analysis. The formulated wafers were characterized by microscopic examination, texture analysis, hydration test, rheological studies, FTIR spectroscopy, water vapor transmission and drug release test. Among the selected formulations, simvastatin-loaded CMC-MC (2:1) wafers exhibited the most desired characteristics for wound dressing application, such as good flexibility, hardness, sponginess, and viscosity. It showed a sustained drug release, which is desirable in wound healing, and was more appropriate for suppurating wounds. In conclusion, simvastatin-loaded CMC-MC (2:1) wafers showing potential for wound dressing applications were successfully developed.
    Matched MeSH terms: Freeze Drying
  5. Application of freeze-drying technology in manufacturing orally disintegrating films
    Liew KB, Odeniyi MA, Peh KK
    Pharm Dev Technol, 2016;21(3):346-53.
    PMID: 25597618 DOI: 10.3109/10837450.2014.1003657
    Freeze drying technology has not been maximized and reported in manufacturing orally disintegrating films. The aim of this study was to explore the freeze drying technology in the formulation of sildenafil orally disintegrating films and compare the physical properties with heat-dried orally disintegrating film. Central composite design was used to investigate the effects of three factors, namely concentration of carbopol, wheat starch and polyethylene glycol 400 on the tensile strength and disintegration time of the film. Heat-dried films had higher tensile strength than films prepared using freeze-dried method. For folding endurance, freeze-dried films showed improved endurance than heat-dried films. Moreover, films prepared using freeze-dried methods were thicker and had faster disintegration time. Formulations with higher amount of carbopol and starch showed higher tensile strength and thickness whereas formulations with higher PEG 400 content showed better flexibility. Scanning electron microscopy showed that the freeze-dried films had more porous structure compared to the heat-dried film as a result of the release of water molecule from the frozen structure when it was subjected to freeze drying process. The sildenafil film was palatable. The dissolution profiles of freeze-dried and heat-dried films were similar to Viagra® with f2 of 51.04 and 65.98, respectively.
    Matched MeSH terms: Freeze Drying
  6. Fulltext Effects of post-drying methods on pomelo fruit peels
    Rahman NFA, Shamsudin R, Ismail A, Karim Shah NNA
    Food Sci Biotechnol, 2016;25(Suppl 1):85-90.
    PMID: 30263490 DOI: 10.1007/s10068-016-0102-y
    Changes in physicochemical properties of moisture, ash, and fat contents, and color, due to freeze and oven post-drying treatments on flavedo, albedo, and lamella pomelo fruit peels were investigated. Physicochemical properties influence consumer acceptability and only a few studies are known. Pomelo peels were subjected to freeze drying and conventional drying at 60°C. Fresh pomelo peel was used as a control. Post-drying treatment changes in moisture, ash, and fat contents were observed, compared to controls. Minimal color changes were observed for freeze drying, compared with oven drying for flavedo, albedo, and lamella. Useful information for evaluation of drying treatments that can be used on pomelo peels is provided.
    Matched MeSH terms: Freeze Drying
  7. Fulltext Comparison of various drying techniques towards the total phenolic content in Jatropha curcas L. root sample
    Ahmad Razi Othman, Intan Safinar Ismail, Norhani Abdullah, Syahida Ahmad
    Journal of Biochemistry, Microbiology and Biotechnology, 2016;4(2):22-24.
    MyJurnal
    Jatropha curcas is a multipurpose plant that has been suggested as a possible cure to
    inflammation. It can be used as a source of animal feed, live fence, biodiesel and in traditional
    medicine. Practitioners have used various extraction techniques to extract the active components
    of the plant. This article compares the efficiency of three methods of drying technique for the
    extraction of the total phenolic content from the plant. The freeze-drying method was the best
    method compared to oven dry and air dry. The freeze-drying method dries J. curcas root sample
    faster and preserve the total phenolic content better than the other methods.
    Matched MeSH terms: Freeze Drying
  8. Omnidirectional Shape Memory Effect via Lyophilization of PEG Hydrogels
    Chen D, Xia X, Wong TW, Bai H, Behl M, Zhao Q, et al.
    Macromol Rapid Commun, 2017 Apr;38(7).
    PMID: 28196300 DOI: 10.1002/marc.201600746
    Device applications of shape memory polymers demand diverse shape changing geometries, which are currently limited to non-omnidirectional movement. This restriction originates from traditional thermomechanical programming methods such as uniaxial, biaxial stretching, bending, or compression. A solvent-modulated programming method is reported to achieve an omnidirectional shape memory behavior. The method utilizes freeze drying of hydrogels of polyethylene glycol networks with a melting transition temperature around 50 °C in their dry state. Such a process creates temporarily fixed macroporosity, which collapses upon heating, leading to significant omnidirectional shrinkage. These shrunken materials can swell in water to form hydrogels again and the omnidirectional programming and recovery can be repeated. The fixity ratio (R f ) and recovery ratio (R r ) can be maintained at 90% and 98% respectively upon shape memory multicycling. The maximum linear recoverable strain, as limited by the maximum swelling, is ≈90%. Amongst various application potentials, one can envision the fabrication of multiphase composites by taking advantages of the omnidirectional shrinkage from a porous polymer to a denser structure.
    Matched MeSH terms: Freeze Drying
  9. Modified porous scaffolds of silk fibroin with mimicked microenvironment based on decellularized pulp/fibronectin for designed performance biomaterials in maxillofacial bone defect
    Sangkert S, Kamonmattayakul S, Chai WL, Meesane J
    J Biomed Mater Res A, 2017 Jun;105(6):1624-1636.
    PMID: 28000362 DOI: 10.1002/jbm.a.35983
    Maxillofacial bone defect is a critical problem for many patients. In severe cases, the patients need an operation using a biomaterial replacement. Therefore, to design performance biomaterials is a challenge for materials scientists and maxillofacial surgeons. In this research, porous silk fibroin scaffolds with mimicked microenvironment based on decellularized pulp and fibronectin were created as for bone regeneration. Silk fibroin scaffolds were fabricated by freeze-drying before modification with three different components: decellularized pulp, fibronectin, and decellularized pulp/fibronectin. The morphologies of the modified scaffolds were observed by scanning electron microscopy. Existence of the modifying components in the scaffolds was proved by the increase in weights and from the pore size measurements of the scaffolds. The modified scaffolds were seeded with MG-63 osteoblasts and cultured. Testing of the biofunctionalities included cell viability, cell proliferation, calcium content, alkaline phosphatase activity (ALP), mineralization and histological analysis. The results demonstrated that the modifying components organized themselves into aggregations of a globular structure. They were arranged themselves into clusters of aggregations with a fibril structure in the porous walls of the scaffolds. The results showed that modified scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin were suitable for cell viability since the cells could attach and spread into most of the pores of the scaffold. Furthermore, the scaffolds could induce calcium synthesis, mineralization, and ALP activity. The results indicated that modified silk fibroin scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin hold promise for use in tissue engineering in maxillofacial bone defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1624-1636, 2017.
    Matched MeSH terms: Freeze Drying
  10. Improved stability of live attenuated vaccine gdhA derivative Pasteurella multocida B:2 by freeze drying method for use as animal vaccine
    Oslan SNH, Halim M, Ramle NA, Saad MZ, Tan JS, Kapri MR, et al.
    Cryobiology, 2017 12;79:1-8.
    PMID: 29037980 DOI: 10.1016/j.cryobiol.2017.10.004
    The efficacy of attenuated strain of gdhA derivative Pasteurella multocida B:2 mutant as a live vaccine to control haemorrhagic septicaemia (HS) disease in cattle and buffaloes has been demonstrated. In order to use P. multocida B:2 mutant as a commercial product, it is essential to optimise its formulation for high viability and stability of the live cells. The effectiveness of freeze-drying process using different protective agent formulations for improving cells viability was explored. Sugar and nitrogen compounds were used as protective agents in freeze-drying and the capability of these compounds in maintaining the viability of mutant P. multocida B:2 during subsequent storage was investigated. A complete loss in viability of freeze-dried mutant P. multocida B:2 was monthly observed until 6-12 months of storage at -30 °C, 4 °C and 27 °C when nitrogen compound or no protective agent was added. Trehalose and sucrose showed significantly high survival rate of 93-95% immediately after freeze-drying and the viability was retained during the subsequent storage at -30 °C and 4 °C. A smooth cell surface without any cell-wall damage was observed for the cells formulated with trehalose under scanning electron micrograph. This study presented a freeze-drying process generating a dried live attenuated vaccine formulation with high stability for commercial applications.
    Matched MeSH terms: Freeze Drying/methods*
  11. Fulltext A Thermostabilized, One-Step PCR Assay for Simultaneous Detection of Klebsiella pneumoniae and Haemophilus influenzae
    Khazani NA, Noor NZ, Yean Yean C, Hasan H, Suraiya S, Mohamad S
    J Trop Med, 2017;2017:7210849.
    PMID: 28386286 DOI: 10.1155/2017/7210849
    Klebsiella pneumoniae and Haemophilus influenzae are two common pathogens associated with respiratory tract infections. The identification of these pathogens using conventional molecular diagnostic tests requires trained personnel, cold-chain transportation, and storage-dependance, which does not render them user-friendly. The aim of this study was to develop a thermostabilized, cold-chain-free, one-step multiplex PCR for simultaneous detection of K. pneumoniae and H. influenzae. The multiplex PCR assay was designed to amplify the php gene of K. pneumoniae (202 bp) and p6 gene of H. influenzae (582 bp). In addition, the specific primer to amplify glm gene of Helicobacter pylori (105 bp) was included as an internal amplification control. Subsequently, the designed primers and all PCR reagents were thermostabilized by lyophilization. The stability of the thermostabilized PCR was evaluated using the Q(10) method. The sensitivity and specificity of performances for thermostabilized PCR were evaluated using 127 clinical isolates and were found to be 100% sensitive and specific. The thermostabilized PCR mix was found to be stable for 30 days and the Q10 accelerated stability was found to be 3.02 months. A cold-chain-free, PCR assay for easy, rapid, and simultaneous detection of K. pneumoniae and H. influenzae was successfully developed in this study.
    Matched MeSH terms: Freeze Drying
  12. Fulltext Comparison of energy and performance from biodegradation of freeze dried and spray dried Algae biomass
    Muhamad Haikal Zainal, Khairul Baqir Alkhair Khairul Amin, Oskar Hasdinor Hassan, Sharifah Aminah Syed Mohamad, Abd Malik Marwan Ali, Fathiah Abdullah, et al.
    Pertanika Journal of Science & Technology, 2017;25(103):53-62.
    MyJurnal
    Many kinds of substrates have been used to investigate bioelectricity production with Microbial Fuel Cell (MFC). Dry algae biomass has the highest maximum power density compared to other substrates due to high carbon sources from its lipid. However, the bacterial digestion of algae biomass is not simple because of the complexity and strength of the algal cell wall structure. An algae biomass extraction is needed to break the cell wall structure and facilitate digestion. Spray drying method is commonly used in highvalue products but may degrade some algal components which are crucial for microbial degradation in MFC, while the freeze-drying method is able to preserve algal cell constituents. The MFC was fed with freeze dried and spray dried algae biomass to produce energy and determine the degradation efficiency. Results showed the average voltage generated was 739 mV and 740 mV from freeze dried and spray dried algae biomass, respectively. The maximum power density of freeze dried algae biomass is 159.9 mW/m2 and spray dried algae biomass is 152.3 mW/m2. Freeze dried algae biomass has 54.2% of COD removal and 28.4% of Coulombic Efficiency while spray dried algae biomass has 50.1% of COD removal and 24.9% of Coulombic Efficiency.
    Matched MeSH terms: Freeze Drying
  13. Fulltext Evaluation of the functional properties of mung bean protein isolate for development of textured vegetable protein
    Brishti, F.H., Zarei, M., Muhammad, S.K.S., Ismail-Fitry, M.R., Shukri, R., Saari, N.
    International Food Research Journal, 2017;24(4):1595-1605.
    MyJurnal
    Mung bean is considered a ‘green pearl’ for its relatively high protein content; however, it has limited application as a raw material for industrial food products. As the potential use of mung beans relies on its protein behavior, this study characterized the functional properties of mung bean protein isolates and the results were compared with soy protein isolates. The protein isolates were prepared from mung bean and soy bean flours via extraction with 1 N NaOH, precipitated at pH 4, and subsequently freeze-dried. The amino acid profile as well as the hydrophilic and hydrophobic ratio of mung bean protein isolate, had been comparable with soy protein isolate. The water and oil absorption capacities as well as the denaturation temperature of mung bean protein isolate, were found to be similar with those of soy bean protein isolate. However, foaming capacity (89.66%) of mung bean protein isolate was higher than that of soy protein isolate (68.66%). Besides, least gelation concentration (LGC) of mung bean protein isolate (12%) was also close to LGC of soy protein isolate (14%), while the protein solubility was comparable between both the isolated proteins. The physical features of the textured mung bean were close to the commercial textured soy protein, which showed a heterogeneous and porous network like matrix when the mung bean flour was extruded to measure its potentiality to produce textured vegetable protein.all seaweed extracts. Results showed that extraction parameters had significant effect (p < 0.05) on the antioxidant compounds and antioxidant capacities of seaweed. Sargassum polycystum portrayed the most antioxidant compounds (37.41 ± 0.01 mg GAE/g DW and 4.54 ± 0.02 mg CE/g DW) and capacities (2.00 ± 0.01 μmol TEAC/g DW and 0.84 ± 0.01 μmol TEAC/g DW) amongst four species of seaweed.
    Matched MeSH terms: Freeze Drying
  14. Antidiabetic Properties of the Tiger's Milk Medicinal Mushroom, Lignosus rhinocerotis (Agaricomycetes), in Streptozotocin-Induced Diabetic Rats
    Nyam KL, Chow CF, Tan CS, Ng ST
    Int J Med Mushrooms, 2017;19(7):607-617.
    PMID: 29199582 DOI: 10.1615/IntJMedMushrooms.2017021186
    Diabetes mellitus is a major cause of morbidity and mortality worldwide. Although scientific evidence supporting its therapeutic efficacy is lacking, the use of the tiger's milk mushroom (TGM; Lignosus rhinocerotis), which is native to tropical areas such as Malaysia, Indonesia, and the Philippines, has been found to contain a very large amount of potential antioxidants. In this study, rats were weighed and then intravenously injected with 35 mg/kg streptozotocin (STZ). Rats were left for 1 week before blood glucose concentrations were measured to determine the onset of diabetes before the next procedure was conducted. Rats with blood glucose exceeding 7.0 mmol/L were considered diabetic and were included in the experiment. All groups were fed their respective treatments twice daily for 2 months throughout the experiment. Antidiabetic and antioxidant properties of freeze-dried TGM powder, such as reduced glutathione (GSH), superoxide dismutase (SOD), lipid peroxidation (LPO), and catalase (CAT) activities, were investigated in liver samples. The biological compounds present in the freeze-dried TGM powder was found to exhibit antidiabetic properties by significantly reducing elevated blood glucose concentrations to a normal range (3.0-7.0 mmol/L) in Sprague-Dawley rats with streptozotocin-induced diabetes, and increasing the body weight of the rats. Freeze-dried TGM powder was also found to possess antioxidant activity by significantly increasing GSH, CAT, and SOD activities while reducing LPO (P < 0.05). THis study shows that freeze-dried TGM powder exhibits significant antidiabetic properties and may be a potential supplement in ameliorating diabetic complications.
    Matched MeSH terms: Freeze Drying
  15. Development of various composition multicomponent chitosan/fish collagen/glycerin 3D porous scaffolds: Effect on morphology, mechanical strength, biostability and cytocompatibility
    Ullah S, Zainol I, Chowdhury SR, Fauzi MB
    Int J Biol Macromol, 2018 May;111:158-168.
    PMID: 29305219 DOI: 10.1016/j.ijbiomac.2017.12.136
    The various composition multicomponent chitosan/fish collagen/glycerin 3D porous scaffolds were developed and investigated the effect of various composition chitosan/fish collagen/glycerin on scaffolds morphology, mechanical strength, biostability and cytocompatibility. The scaffolds were fabricated via freeze-drying technique. The effects of various compositions consisting in 3D scaffolds were investigated via FT-IR analysis, porosity, swelling and mechanical tests, and effect on the morphology of scaffolds investigated microscopically. The biostability and cytocompatibility tests were used to explore the ability of scaffolds to use for tissue engineering application. The average pore sizes of scaffolds were in range of 100.73±27.62-116.01±52.06, porosity 71.72±3.46-91.17±2.42%, tensile modulus in dry environment 1.47±0.08-0.17±0.03MPa, tensile modulus in wet environment 0.32±0.03-0.14±0.04MPa and biodegradation rate (at day 30) 60.38±0.70-83.48±0.28%. In vitro culture of human fibroblasts and keratinocytes showed that the various composition multicomponent 3D scaffolds were good cytocompatibility however, the scaffolds contained high amount of fish collagen excellently facilitated cell proliferation and adhesion. It was found that the high amount fish collagen and glycerin scaffolds have high porosity, enough mechanical strength and biostability, and excellent cytocompatibility.
    Matched MeSH terms: Freeze Drying
  16. Fulltext Dry Thermotropic Glycolipid Self-Assembly:A Review
    Hashim R, Zahid NI, Velayutham TS, Aripin NFK, Ogawa S, Sugimura A
    J Oleo Sci, 2018 Jun 01;67(6):651-668.
    PMID: 29760332 DOI: 10.5650/jos.ess17261
    Also recognized as carbohydrate liquid crystals, glycolipids are amphiphiles whose basic unit comprises of a sugar group attached to an alkyl chain. Glycolipids are amphitropic, which means these materials form liquid crystal self-assemblies when dry (thermotropic) as well as when dissolved in solvents (lyotropic/surfactants) such as water. Many glycolipids are also naturally derived since these can be found in cell membranes. Their membrane and surfactant functions are largely understood through their lyotropic properties. While glycolipids are expected to play major roles as eco-friendly surfactants in the global surfactant market, their usefulness as thermotropic liquid crystal material is, to date, unknown, due to relatively lack of research performed and data reported in the literature. Understandably since glycolipids are hygroscopic with many hydroxy groups, removing the last trace water is very challenging. In recent time, with careful lyophilization and more consistent characterization technique, some researchers have attempted serious studies into "dry" or anhydrous glycolipids. Motivated by possible developments of novel thermotropic applications, some results from these studies also provide surprising new understanding to support conventional wisdom of the lyotropic systems. Here we review the dry state of glycosides, a family of glycolipids whose sugar headgroup is linked to the lipid chain via a glycosidic oxygen linker. The structure property relationship of both linear and anhydrous Guerbet glycosides will be examined. In particular, how the variation of sugar stereochemistry (e.g. anomer vs. epimer), the chain length and chain branching affect the formation of thermotropic liquid crystals phases, which not only located under equilibrium but also far from equilibrium conditions (glassy phase) are scrutinized. The dry glycolipid assembly has been subjected to electric and magnetic fields and the results show interesting behaviors including a possible transient current generation.
    Matched MeSH terms: Freeze Drying
  17. Fulltext Enhanced physicochemical stability and efficacy of angiotensin I-converting enzyme (ACE) - inhibitory biopeptides by chitosan nanoparticles optimized using Box-Behnken design
    Auwal SM, Zarei M, Tan CP, Basri M, Saari N
    Sci Rep, 2018 Jul 10;8(1):10411.
    PMID: 29991723 DOI: 10.1038/s41598-018-28659-5
    Bromelain-generated biopeptides from stone fish protein exhibit strong inhibitory effect against ACE and can potentially serve as designer food (DF) with blood pressure lowering effect. Contextually, the DF refer to the biopeptides specifically produced to act as ACE-inhibitors other than their primary role in nutrition and can be used in the management of hypertension. However, the biopeptides are unstable under gastrointestinal tract (GIT) digestion and need to be stabilized for effective oral administration. In the present study, the stone fish biopeptides (SBs) were stabilized by their encapsulation in sodium tripolyphosphate (TPP) cross-linked chitosan nanoparticles produced by ionotropic gelation method. The nanoparticles formulation was then optimized via Box-Behnken experimental design to achieve smaller particle size (162.70 nm) and high encapsulation efficiency (75.36%) under the optimum condition of SBs:Chitosan mass ratio (0.35), homogenization speed (8000 rpm) and homogenization time (30 min). The SBs-loaded nanoparticles were characterized for morphology by transmission electron microscopy (TEM), physicochemical stability and efficacy. The nanoparticles were then lyophilized and analyzed using Fourier transform infra-red spectroscopy (FTIR) and X-ray diffraction (XRD). The results obtained indicated a sustained in vitro release and enhanced physicochemical stability of the SBs-loaded nanoparticles with smaller particle size and high encapsulation efficiency following long period of storage. Moreover, the efficacy study revealed improved inhibitory effect of the encapsulated SBs against ACE following simulated GIT digestion.
    Matched MeSH terms: Freeze Drying
  18. Fulltext The effect of freeze-dried Carica papaya leaf juice treatment on NS1 and viremia levels in dengue fever mice model
    Mohd Abd Razak MR, Mohmad Misnan N, Md Jelas NH, Norahmad NA, Muhammad A, Ho TCD, et al.
    BMC Complement Altern Med, 2018 Dec 05;18(1):320.
    PMID: 30518360 DOI: 10.1186/s12906-018-2390-7
    BACKGROUND: Carica papaya leaf juice (CPLJ) was well known for its thrombocytosis activity in rodents and dengue patients. However, the effect of CPLJ treatment on other parameters that could contribute to dengue pathogenesis such as nonstructural protein 1 (NS1) production and viremia level have never been highlighted in any clinical and in vivo studies. The aim of this study is to investigate the effect of freeze-dried CPLJ treatment on NS1 and viremia levels of dengue fever mouse model.

    METHODS: The dengue infection in mouse model was established by inoculation of non-mouse adapted New Guinea C strain dengue virus (DEN-2) in AG129 mice. The freeze-dried CPLJ compounds were identified by Ultra-High Performance Liquid Chromatography High Resolution Accurate Mass Spectrometry analysis. The infected AG129 mice were orally treated with 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ, starting on day 1 post infection for 3 consecutive days. The blood samples were collected from submandibular vein for plasma NS1 assay and quantitation of viral RNA level by quantitative reverse transcription PCR.

    RESULTS: The AG129 mice infected with dengue virus showed marked increase in the production of plasma NS1, which was detectable on day 1 post infection, peaked on day 3 post-infection and started to decline from day 5 post infection. The infection also caused splenomegaly. Twenty-four compounds were identified in the freeze-dried CPLJ. Oral treatment with 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ did not affect the plasma NS1 and dengue viral RNA levels. However, the morbidity level of infected AG129 mice were slightly decreased when treated with freeze-dried CPLJ.

    CONCLUSION: Oral treatment of 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ at the onset of viremia did not affect the plasma NS1 and viral RNA levels in AG129 mice infected with non-mouse adapted New Guinea C strain dengue virus.

    Matched MeSH terms: Freeze Drying
  19. Fulltext Effect of freeze-dried Carica papaya leaf juice on inflammatory cytokines production during dengue virus infection in AG129 mice
    Norahmad NA, Mohd Abd Razak MR, Mohmad Misnan N, Md Jelas NH, Sastu UR, Muhammad A, et al.
    BMC Complement Altern Med, 2019 Feb 11;19(1):44.
    PMID: 30744623 DOI: 10.1186/s12906-019-2438-3
    BACKGROUND: Carica papaya leaves have been used for traditional treatment of dengue fever and have been reported to exhibit an immunomodulatory activity by affecting the level of cytokine production in vitro and in vivo. Due to the lack of adequate in vivo evidence in dengue disease model, the present study was initiated to screen and identify the cytokines affected by freeze-dried C. papaya leaf juice (FCPLJ) treatment in AG129 mice infected with DEN-2 dengue virus.

    METHODS: The AG129 mice were fed orally with FCPLJ for 3 consecutive days after 24 h of dengue virus inoculation. Plasma cytokines were screened by using ProcartaPlex immunoassay. The gene expression in the liver was analyzed by using RT2 Profiler PCR Array.

    RESULTS: The results showed that FCPLJ treatment has increased the plasma CCL2/MCP-1 level during peak of viremia. Gene expression study has identified 8 inflammatory cytokine genes which were downregulated in the liver of infected AG129 mice treated with FCPLJ. The downregulated inflammatory cytokine genes were CCL6/MRP-1, CCL8/MCP-2, CCL12/MCP-5, CCL17/TARC, IL1R1, IL1RN/IL1Ra, NAMPT/PBEF1 and PF4/CXCL4.

    CONCLUSION: The findings indicated the possible immunomodulatory role of FCPLJ during dengue virus infection in AG129 mice.

    Matched MeSH terms: Freeze Drying
  20. Fulltext Freeze-Dried Lopinavir-Loaded Nanostructured Lipid Carriers for Enhanced Cellular Uptake and Bioavailability: Statistical Optimization, in Vitro and in Vivo Evaluations
    Khan AA, Mudassir J, Akhtar S, Murugaiyah V, Darwis Y
    Pharmaceutics, 2019 Feb 25;11(2).
    PMID: 30823545 DOI: 10.3390/pharmaceutics11020097
    Nanostructured lipid carriers (NLCs) loaded with lopinavir (LPV) were prepared by the high-shear homogenization method. The LPV-NLCs formulations were freeze-dried using trehalose as a cryoprotectant. In vitro release studies in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8) showed a burst release. The optimized freeze-dried formulation (LPV-NLC-7-Tres) had a particle size (PS), polydispersity index (PdI), zeta potential (ZP) and % entrapment efficiency (%EE) of 286.8 ± 1.3 nm, 0.413 ± 0.017, -48.6 ± 0.89 mV and 88.31 ± 2.04%, respectively. The optimized formulation observed by transmission and scanning electron microscopes showed a spherical shape. Differential scanning calorimetry study revealed the absence of chemical interaction between the drug and lipids. In vitro cellular uptake study using Caco-2 cell line showed a higher LPV uptake from LPV-NLC-7-Tres formulation compared to the free LPV-suspension. The 6-month stability study showed a minimum rise of ~40 nm in PS, while no significant changes in PdI, ZP and drug content of the LPV-NLC-7-Tres formulation stored at 5 °C ± 3 °C. The bioavailability of LPV following oral administration of LPV-NLC-7-Tres in male Wistar rats was found 6.98-fold higher than the LPV-suspension. In conclusion, the nanostructure lipid carriers are potential carriers for improving the oral bioavailability of lopinavir.
    Matched MeSH terms: Freeze Drying
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links