Displaying publications 41 - 60 of 69 in total

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  1. Mohammadi M, Hassan MA, Phang LY, Ariffin H, Shirai Y, Ando Y
    Biotechnol Lett, 2012 Feb;34(2):253-9.
    PMID: 22038551 DOI: 10.1007/s10529-011-0783-5
    A new halogen-free and environmental-friendly method using water and ethanol is developed as an alternative for the recovery of polyhydroxyalkanoates (PHA) from recombinant Cupriavidus necator in comparison to the established chloroform extraction method. After optimisation, our results showed that the halogen-free method produced a PHA with 81% purity and 96% recovery yield, in comparison to the chloroform extraction system which resulted in a highly pure PHA with 95% yield. Although the purity of the PHA using the new method is lower, the molecular weight of the extracted PHA is not compromised. This new method can be further developed as an alternative and more environmental-friendly method for industrial application.
    Matched MeSH terms: Ethanol/chemistry
  2. Murugesu K, Murugaiyah V, Saghir SAM, Asmawi MZ, Sadikun A
    Curr Pharm Biotechnol, 2017;18(14):1132-1140.
    PMID: 29564975 DOI: 10.2174/1389201019666180322111800
    BACKGROUND: Ethanolic extract of G. procumbens leaves has been previously shown to possess antihyperlipidemic effects.

    OBJECTIVE: This study was designed to prepare caffeoylquinic acids rich and poor fractions of the ethanolic extract using resin column technology and compare their antihyperlipidemic and antioxidant potentials.

    RESULTS: Among the treatment groups, caffeoylquinic acids rich fraction (F2) and chlorogenic acid (CA, one of the major caffeoylquinic acids) showed potent antihyperlipidemic effects, with significant reductions in total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C), very low-density lipoprotein-cholesterol (VLDL-C), atherogenic index (AI) and coronary risk index (CRI) (p<0.01 or better) compared to the hyperlipidemic control at the 58 h. The effect was better than that of ethanolic extract. In addition, only F2 significantly increased the high-density lipoproteincholesterol (HDL-C) level (p<0.05). F2 showed better effect than CA alone (60 mg) despite the fact that it only contained 9.81 mg CA/1000 mg dose. The findings suggest that the di-caffeoylquinic acids (86.61 mg/g dose) may also in part be responsible for the potent antihyperlipidemic effect shown by the F2. Likewise, F2 showed the highest antioxidant activity. Thus, simple fractionation of ethanolic extract using the Amberlite XAD-2 resin technique had successfully enriched the caffeoylquinic acids into F2 with improved antihyperlipidemic and antioxidant capacities than that of the ethanolic extract.

    CONCLUSION: The resin separation technology may find application in caffeoylquinic acids enrichment of plant extracts for pre-clinical studies. The F2 has potential for development into phytopharmaceuticals as adjunct therapy for management of hyperlipidemia.

    Matched MeSH terms: Ethanol/chemistry
  3. Myint S, Daud WR, Mohamad AB, Kadhum AA
    J Chromatogr B Biomed Appl, 1996 Apr 26;679(1-2):193-5.
    PMID: 8998560
    An ethanolic extract of cloves was analyzed by gas chromatography directly to identify eugenol and other major phenolic compounds without previous separation of other components. Separation was performed on a fused-silica capillary column of 30 m x 0.53 mm I.D., 0.53 microns film thickness. The detector was a flame ionization detector. Helium gas at a flow-rate of 3 ml/min was used as a carrier gas. The analysis were performed with linear temperature programming. Nine components were detected and special attention was given to the major phenolic compound, eugenol.
    Matched MeSH terms: Ethanol/chemistry*
  4. Ng HS, Ng TC, Kee PE, Tan JS, Yim HS, Lan JC
    J Biosci Bioeng, 2020 Feb;129(2):237-241.
    PMID: 31629635 DOI: 10.1016/j.jbiosc.2019.08.013
    Aqueous biphasic flotation (ABF) integrates aqueous biphasic system (ABS) and solvent sublation for recovery of target biomolecules. The feasibility of the alcohol/salt ABF for exclusive partition of cytochrome c to one specific phase of the system was investigated. Aliphatic alcohols of different carbon chain length (ethanol, 1-propanol and 2-propanol) and salts (sulfate, phosphate and citrate) were used for the phase formation. The effects of phase composition, concentration of sample loading, pH, flotation time and flow rate of the system on the partition efficiency of cytochrome c were determined. Cytochrome c was exclusively partitioned to the alcohol-rich top phase of the ABF of 18% (w/w) ethanol and 26% (w/w) ammonium sulfate with pH 6 and 20% (w/w) of sample loading. Highest partition coefficient (K) of 6.85 ± 0.21 and yield (YT) of 99.40% ± 0.02 were obtained with optimum flotation rate of 10 mL/min and flow rate of 10 min.
    Matched MeSH terms: Ethanol/chemistry
  5. Ng HS, Chai CXY, Chow YH, Loh WLC, Yim HS, Tan JS, et al.
    J Biosci Bioeng, 2018 May;125(5):585-589.
    PMID: 29339003 DOI: 10.1016/j.jbiosc.2017.12.010
    Xylanase enzyme degrades linear polysaccharide β-1,4 xylan and the hemicellulose of the plant cell wall. There is a growing demand in finding a cost-effective alternative for industrial scale production of xylanase with high purity for pharmaceutical applications. In this study, an alcohol/salt aqueous biphasic system (ABS) was adopted to recover xylanase from the Bacillus subtilis fermentation broth. The effects of several ABS parameters such as types and concentrations of alcohols and salts (i.e., sulphate, phosphate, and citrate), amount of crude loading and pH of the system on the recovery of xylanase were investigated. Partition coefficient of xylanase (KE), selectivity (S) and yield (YT) of xylanase in top phase of the ABS were measured. Highest KE (6.58 ± 0.05) and selectivity (4.84 ± 0.33) were recorded in an ABS of pH 8 composed of 26% (w/w) 1-propanol, 18% (w/w) ammonium sulphate. High YT of 71.88% ± 0.15 and a purification fold (PFT) of 5.74 ± 0.33 were recorded with this optimum recovery of xylanase using alcohol/salt ABS. The purity of xylanase recovered was then qualitatively verified with sodium dodecyl sulphate (SDS) gel electrophoresis. The SDS profile revealed the purified xylanase was successfully obtained in the top phase of the one-step 1-propanol/sulphate ABS with a distinct single band.
    Matched MeSH terms: Ethanol/chemistry
  6. Pan Y, Tiong KH, Abd-Rashid BA, Ismail Z, Ismail R, Mak JW, et al.
    J Ethnopharmacol, 2012 Sep 28;143(2):586-91.
    PMID: 22885070 DOI: 10.1016/j.jep.2012.07.024
    Labisa pumila (LP), popularly known with its local name, Kacip Fatimah, is a well known herb grown in Indochina and Southeast Asia and is traditionally used to regain energy after giving birth in women. The propensity of LP to cause drug-herb interaction via cytochrome P450 (CYP) enzyme system has not been investigated.
    Matched MeSH terms: Ethanol/chemistry
  7. Pratika RA, Wijaya K, Utami M, Mulijani S, Patah A, Alarifi S, et al.
    Chemosphere, 2023 Nov;341:139822.
    PMID: 37598950 DOI: 10.1016/j.chemosphere.2023.139822
    The dehydration of ethanol into diethyl ether over a SO4/SiO2 catalyst was investigated. The SO4/SiO2 catalysts were prepared by the sulfation method using 1, 2, and 3 M of sulfuric acid (SS1, SS2, and SS3) via hydrothermal treatment. This study is focused on the synthesis of a SO4/SiO2 catalyst with high total acidity that can be subsequently utilized to convert ethanol into diethyl ether. The total acidity test revealed that the sulfation process increased the total acidity of SiO2. The SS2 catalyst (with 2 M sulfuric acid) displayed the highest total acidity of 7.77 mmol/g, whereas the SiO2 total acidity was only 0.11 mmol/g. Meanwhile, the SS3 catalyst (with 3 M sulfuric acid) has a lower total acidity of 7.09 mmol/g due to the distribution of sulfate groups on the surface having reached its optimum condition. The crystallinity and structure of the SS2 catalyst were not affected by the hydrothermal treatment or the sulfate process on silica. Furthermore, The SS2 catalyst characteristics in the presence of sulfate lead to a flaky surface in the morphology and non-uniform particle size. In addition, the surface area and pore volume of the SS2 catalyst decreased (482.56-172.26 m2/g) and (0.297-0.253 cc/g), respectively, because of the presence of sulfate on the silica surface. The SS2 catalyst's pore shape information explains the formation of non-uniform pore sizes and shapes. Finally, the activity and selectivity of SO4/SiO2 catalysts in the conversion of ethanol to diethyl ether yielded the highest ethanol conversion of 70.01% and diethyl ether product of 9.05% from the SS2 catalyst (the catalyst with the highest total acidity). Variations in temperature reaction conditions (175-225 °C) show an optimum reaction temperature to produce diethyl ether at 200 °C (11.36%).
    Matched MeSH terms: Ethanol/chemistry
  8. R R
    Appl Biochem Biotechnol, 2022 Jan;194(1):176-186.
    PMID: 34762268 DOI: 10.1007/s12010-021-03742-2
    Hellenia speciosa (J.Koenig) S.R. Dutta is a plant species belonging to the family Costaceae. It is widely distributed in China, India, Malaysia, Indonesia, tropical, and subtropical Asia. In Ayurveda, the rhizome of this plant has been extensively used to treat fever, rash, asthma, bronchitis, and intestinal worms. The objective of the present study was to investigate the phytochemical constituents of the leaf of Hellenia speciosa using gas chromatography and mass spectroscopy analysis (GC-MS). The GC-MS analysis revealed the presence of 17 phytochemical components in the ethanolic leaf extract of Hellenia speciosa. The prevailing bioactive compounds present in Hellenia speciosa were thymol (RT-10.019; 3.59%), caryophyllene (RT-11.854; 0.62%), caryophyllene oxide (RT-13.919; 1.34%), artumerone (RT-14.795; 1.35%), hexadecanoic acid methyl ester (RT-17.536; 2.77%), 9,12-octadecanoic acid methyl ester (RT-19.163; 1.35%), squalene (RT-24.980; 1.19%), piperine (RT-25.745; 3.11%), beta tocopherol (RT-26.681; 2.88%), vitamin E (RT-27.290; 2.64%), progesterone (RT-29.608; 3.18%), caparratriene (RT-29.861; 9.72%), and testosterone (RT-30.73; 5.81%). The compounds were identified by comparing their retention time and peak area with that of the literature and by interpretation of mass spectra. The results and findings of the present study suggest that the plant leaf can be used as a valuable source in the field of herbal drug discovery. The presence of bioactive compounds justifies the use of plant leaves for treating various diseases with fewer side effects and recommended the plant of pharmaceutical importance. However, further studies are needed to undertake its bioactivity and toxicity profile.
    Matched MeSH terms: Ethanol/chemistry*
  9. Radzali SA, Markom M, Saleh NM
    Molecules, 2020 Dec 11;25(24).
    PMID: 33322389 DOI: 10.3390/molecules25245859
    A preliminary study was conducted to study the effects of different types and concentrations of co-solvents based on yield, composition and antioxidants capacity of extract prior to optimization studies of supercritical fluid extraction (SFE) of Labisia pumila (locally referred to as 'kacip fatimah'). The following co-solvents were studied prior to the optimization of supercritical carbon dioxide (SC-CO2) technique: ethanol, water, methanol, as well as aqueous solutions of ethanol-water and methanol-water (50% and 70% v/v). By using the selected co-solvents, identification of phenolic acids (gallic acid, methyl gallate and caffeic acid) was determined by using High-Performance Liquid Chromatography (HPLC). Then, the antioxidant capacity was evaluated by using three different assays: total phenolic content (TPC), ferric reducing/antioxidant power (FRAP) and free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). SC-CO2 with 70% ethanol-water co-solvent was superior in terms of a higher combination of phenolic compounds extracted and antioxidants capacity. Overall, SC-CO2 with co-solvent 70% ethanol-water technique was efficient in extracting phenolic compounds from L. pumila, and thus the usage of this solvent system should be considered for further optimization studies.
    Matched MeSH terms: Ethanol/chemistry
  10. Rahim NA, Hassandarvish P, Golbabapour S, Ismail S, Tayyab S, Abdulla MA
    Biomed Res Int, 2014;2014:416409.
    PMID: 24783203 DOI: 10.1155/2014/416409
    Herbal medicines appeared promising in prevention of many diseases. This study was conducted to investigate the gastroprotective effect of Curcuma xanthorrhiza leaf in the rats induced gastric ulcer by ethanol. Normal and ulcer control received carboxymethycellulose (5 mL/kg) orally, positive control was administered with 20 mg/kg omeprazole (reference drug) and 2 groups were received 250 mg/kg and 500 mg/kg of the leaf extract, respectively. To induce of gastric ulcers formation, ethanol (5 mL/kg) was given orally to all groups except normal control. Gross ulcer areas, histology, and amount of prostaglandin E2, superoxide dismutase and malondialdehyde were assessed to determine the potentiality of extract in prevention against gastric ulcers. Oral administration of extract showed significant gastric protection effect as the ulcer areas was remarkably decreased. Histology observation showed less edema and leucocytes infiltration as compared with the ulcer control which exhibited severe gastric mucosa injury. Furthermore, the leaf extract elevated the mucus weight, level of prostaglandin E2 and superoxide dismutase. The extract also reduced malondialdehyde amount significantly. Results showed leaf extract of Curcuma xanthorrhiza can enhanced the gastric protection and sustained the integrity of gastric mucosa structure. Acute toxicity test did not showed any sign of toxicity (2 g/kg and 5 g/kg).
    Matched MeSH terms: Ethanol/chemistry
  11. Raj ST, Puspanadan S, Gan CY, Tan JS
    Int J Biol Macromol, 2024 May;267(Pt 2):131376.
    PMID: 38608981 DOI: 10.1016/j.ijbiomac.2024.131376
    Diabetes is a chronic, metabolic disease characterized by hyperglycemia resulting from either insufficient insulin production or impaired cellular response to insulin. Exopolysaccharides (EPS) produced by Lactobacillus spp. demonstrated promising therapeutic potential in terms of their anti-diabetic properties. Extraction and purification of EPS produced by Lactobacillus acidophilus and Limosilactobacillus reuteri were performed using ethanol precipitation, followed by alcohol/salt based aqueous two-phase system (ATPS). The purification process involved ethanol precipitation followed by an alcohol/salt-based ATPS. The study systematically investigated various purification parameters in ATPS, including ethanol concentration, type and concentration of ionic liquid, type and concentration of salt and pH of salt. Purified EPS contents from L. acidophilus (63.30 μg/mL) and L. reuteri (146.48 μg/mL) were obtained under optimum conditions of ATPS which consisted of 30 % (w/w) ethanol, 25 % (w/w) dipotassium hydrogen phosphate at pH 10 and 2 % (w/w) 1-butyl-3-methylimidazolium octyl sulfate. The extracted EPS content was determined using phenol sulphuric acid method. In α-amylase inhibition tests, the inhibitory rate was found to be 92.52 % (L. reuteri) and 90.64 % (L. acidophilus), while in α-glucosidase inhibition tests, the inhibitory rate was 73.58 % (L. reuteri) and 68.77 % (L. acidophilus), based on the optimized parameters selected in ATPS. These results suggest that the purified EPS derived from the postbiotics of Lactobacillus spp. hold promise as potential antidiabetic agents.
    Matched MeSH terms: Ethanol/chemistry
  12. Ramli S, Radu S, Shaari K, Rukayadi Y
    Biomed Res Int, 2017;2017:9024246.
    PMID: 29410966 DOI: 10.1155/2017/9024246
    The aim of this study was to determine antibacterial activity of S. polyanthum L. (salam) leaves extract foodborne pathogens. All the foodborne pathogens were inhibited after treating with extract in disk diffusion test with range 6.67 ± 0.58-9.67 ± 0.58 mm of inhibition zone. The range of MIC values was between 0.63 and 1.25 mg/mL whereas MBC values were in the range 0.63 mg/mL to 2.50 mg/mL. In time-kill curve, L. monocytogenes and P. aeruginosa were found completely killed after exposing to extract in 1 h incubation at 4x MIC. Four hours had been taken to completely kill E. coli, S. aureus, V. cholerae, and V. parahaemolyticus at 4x MIC. However, the population of K. pneumoniae, P. mirabilis, and S. typhimurium only reduced to 3 log CFU/mL. The treated cell showed cell rupture and leakage of the cell cytoplasm in SEM observation. The significant reduction of natural microflora in grapes fruit was started at 0.50% of extract at 5 min and this concentration also was parallel to sensory attributes acceptability where application of extract was accepted by the panellists until 5%. In conclusion, S. polyanthum extract exhibits antimicrobial activities and thus might be developed as natural sanitizer for washing raw food materials.
    Matched MeSH terms: Ethanol/chemistry*
  13. Saleh MSM, Bukhari DAM, Siddiqui MJA, Kasmuri AR, Murugesu S, Khatib A
    Nat Prod Res, 2020 May;34(9):1341-1344.
    PMID: 30678487 DOI: 10.1080/14786419.2018.1560295
    Different extraction processes were employed to extract bioactive metabolites from Salacca zalacca flesh by a range of aqueous and organic solvents. The highest extraction yield was obtained by 50% ethanol extract of SE (73.18 ± 4.35%), whereas SFE_1 showed the lowest yield (0.42 ± 0.08%). All extracts were evaluated for in vitro α-glucosidase inhibitory activity, measured by their IC50 values in comparison to that of quercetin, the positive control (IC50 = 2.7 ± 0.7 μg/mL). The lowest α-glucosidase inhibitory activity was indicated by water extract of SE (IC50 = 724.3 ± 42.9 μg/mL) and the highest activity was demonstrated by 60% ethanol extract by UAE (IC50 = 16.2 ± 2.4 μg/mL). All extracts were analysed by GC-MS and identified metabolites like carbohydrates, fatty acids, organic acids, phenolic acids, sterols and alkane-based compounds etcetera that may possess the potential as α-glucosidase inhibitor and may attribute to the α-glucosidase inhibitory activity.
    Matched MeSH terms: Ethanol/chemistry
  14. Shafaei A, Esmailli K, Farsi E, Aisha AF, Abul Majid AM, Ismail Z
    PMID: 26467526 DOI: 10.1186/s12906-015-0885-z
    Orthosiphon stamineus (OS) Benth is a medicinal plant and native in Southeast Asia. Pharmacological effects of OS are attributed to the presence of lipophilic flavones. However; lipophilic compounds suffer from poor aqueous solubility which limits the OS oral bioavailability and therapeutic applications. Therefore, OS was prepared in nano formulation form using liposomes from soybean phospholipids. The aim of the present study is to evaluate the in vitro genotoxicity and in vivo oral toxicity of nano liposomes of OS ethanolic extract (OS-EL).
    Matched MeSH terms: Ethanol/chemistry
  15. Shukor H, Abdeshahian P, Al-Shorgani NK, Hamid AA, Rahman NA, Kalil MS
    Bioresour Technol, 2016 Oct;218:257-64.
    PMID: 27372004 DOI: 10.1016/j.biortech.2016.06.084
    Catalytic depolymerization of mannan composition of palm kernel cake (PKC) by mannanase was optimized to enhance the release of mannan-derived monomeric sugars for further application in acetone-butanol-ethanol (ABE) fermentation. Efficiency of enzymatic hydrolysis of PKC was studied by evaluating effects of PKC concentration, mannanase loading, hydrolysis pH value, reaction temperature and hydrolysis time on production of fermentable sugars using one-way analysis of variance (ANOVA). The ANOVA results revealed that all factors studied had highly significant effects on total sugar liberated (P<0.01). The optimum conditions for PKC hydrolysis were 20% (w/v) PKC concentration, 5% (w/w) mannanase loading, hydrolysis pH 4.5, 45°C temperature and 72h hydrolysis time. Enzymatic experiments in optimum conditions revealed total fermentable sugars of 71.54±2.54g/L were produced including 67.47±2.51g/L mannose and 2.94±0.03g/L glucose. ABE fermentation of sugar hydrolysate by Clostridium saccharoperbutylacetonicum N1-4 resulted in 3.27±1.003g/L biobutanol.
    Matched MeSH terms: Ethanol/chemistry
  16. Tahmasebi-Boldaji R, Hatamipour MS, Khanahmadi M, Sadeh P, Najafipour I
    Ultrason Sonochem, 2019 Oct;57:89-97.
    PMID: 31208622 DOI: 10.1016/j.ultsonch.2019.05.018
    This paper presents the successful application of ultrasound-assisted packed-bed (UAE-PB) method for the extraction of hypericin from the Hypericum perfuratum L. The Soxhlet system was utilized for the determination of suitable solvent from ethanol, methanol or from the mixture of different proportions of ethanol-methanol. The mixture of 50:50 v/v ethanol-methanol was obtained to be the most suitable solvent since it led to the highest extraction amount of hypericin. The extraction amount of hypericin increased by 13.6% and 21.4% when the solvent changed from pure methanol to the mixture of 50:50 v/v ethanol-methanol for the extraction time of 3 and 8 h, respectively. Subsequently, the extraction was conducted through the UAE-PB, and the effects of temperature, time, and the ratio of solvent to the dried plant were studied. The response surface method (RSM) was used to investigate the effect of parameters on the extraction in the UAE-PB system. At the temperature of 60 °C, extraction time of 105 min, and the solvent to plant ratio of 15.3, the maximum extraction yield of hypericin was achieved. In the optimal conditions, the amount of extraction was 0.112 mg hypericin/g dried plant, which was in accordance with the optimized predicted value (0.111 mg hypericin/g dried plant) from Design-Expert software.
    Matched MeSH terms: Ethanol/chemistry; Methanol/chemistry
  17. Tan HT, Lee KT, Mohamed AR
    Bioresour Technol, 2010 Jul;101(14):5719-27.
    PMID: 20223656 DOI: 10.1016/j.biortech.2010.02.023
    Recently, second-generation bio-ethanol (SGB), which utilizes readily available lignocellulosic biomass has received much interest as another potential source of liquid biofuel comparable to biodiesel. Thus the aim of this paper is to determine the exergy efficiency and to compare the effectiveness of SGB and palm methyl ester (PME) processes. It was found that the production of bio-ethanol is more thermodynamically sustainable than that of biodiesel as the net exergy value (NExV) of SGB is 10% higher than that of PME. Contrarily, the former has a net energy value (NEV) which is 9% lower than the latter. Despite this, SGB is still strongly recommended as a potential biofuel because SGB production can help mitigate several detrimental impacts on the environment.
    Matched MeSH terms: Ethanol/chemistry
  18. Tan IS, Lee KT
    Carbohydr Polym, 2015 Jun 25;124:311-21.
    PMID: 25839825 DOI: 10.1016/j.carbpol.2015.02.046
    The aim of this study is to investigate the technical feasibility of converting macroalgae cellulosic residue (MCR) into bioethanol. An attempt was made to present a novel, environmental friendly and economical pretreatment process that enhances enzymatic conversion of MCR to sugars using Dowex (TM) Dr-G8 as catalyst. The optimum yield of glucose reached 99.8% under the optimal condition for solid acid pretreatment (10%, w/v biomass loading, 4%, w/v catalyst loading, 30min, 120°C) followed by enzymatic hydrolysis (45FPU/g of cellulase, 52CBU/g of β-glucosidase, 50°C, pH 4.8, 30h). The yield of sugar obtained was found more superior than conventional pretreatment process using H2SO4 and NaOH. Biomass loading for the subsequent simultaneous saccharification and fermentation (SSF) of the pretreated MCR was then optimized, giving an optimum bioethanol yield of 81.5%. The catalyst was separated and reused for six times, with only a slight drop in glucose yield.
    Matched MeSH terms: Ethanol/chemistry
  19. Tay PY, Tan CP, Abas F, Yim HS, Ho CW
    Molecules, 2014 Aug 14;19(8):12304-19.
    PMID: 25153858 DOI: 10.3390/molecules190812304
    The effects of ethanol concentration (0%-100%, v/v), solid-to-solvent ratio (1:10-1:60, w/v) and extraction time (30-180 min) on the extraction of polyphenols from agarwood (Aquilaria crassna) were examined. Total phenolic content (TPC), total flavonoid content (TFC) and total flavanol (TF) assays and HPLC-DAD were used for the determination and quantification of polyphenols, flavanol gallates (epigallocatechin gallate--EGCG and epicatechin gallate--ECG) and a benzophenone (iriflophenone 3-C-β-glucoside) from the crude polyphenol extract (CPE) of A. crassna. 2,2'-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was used to evaluate the antioxidant capacity of the CPE. Experimental results concluded that ethanol concentration and solid-to-solvent ratio had significant effects (p<0.05) on the yields of polyphenol and antioxidant capacity. Extraction time had an insignificant influence on the recovery of EGCG, ECG and iriflophenone 3-C-β-glucoside, as well as radical scavenging capacity from the CPE. The extraction parameters that exhibited maximum yields were 40% (v/v) ethanol, 1:60 (w/v) for 30 min where the TPC, TFC, TF, DPPH, EGCG, ECG and iriflophenone 3-C-β-glucoside levels achieved were 183.5 mg GAE/g DW, 249.0 mg QE/g DW, 4.9 mg CE/g DW, 93.7%, 29.1 mg EGCG/g DW, 44.3 mg ECG/g DW and 39.9 mg iriflophenone 3-C-β-glucoside/g DW respectively. The IC50 of the CPE was 24.6 mg/L.
    Matched MeSH terms: Ethanol/chemistry
  20. Tharsika T, Haseeb AS, Akbar SA, Sabri MF, Hoong WY
    Sensors (Basel), 2014;14(8):14586-600.
    PMID: 25116903 DOI: 10.3390/s140814586
    An inexpensive single-step carbon-assisted thermal evaporation method for the growth of SnO2-core/ZnO-shell nanostructures is described, and the ethanol sensing properties are presented. The structure and phases of the grown nanostructures are investigated by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. XRD analysis indicates that the core-shell nanostructures have good crystallinity. At a lower growth duration of 15 min, only SnO2 nanowires with a rectangular cross-section are observed, while the ZnO shell is observed when the growth time is increased to 30 min. Core-shell hierarchical nanostructures are present for a growth time exceeding 60 min. The growth mechanism for SnO2-core/ZnO-shell nanowires and hierarchical nanostructures are also discussed. The sensitivity of the synthesized SnO2-core/ZnO-shell nanostructures towards ethanol sensing is investigated. Results show that the SnO2-core/ZnO-shell nanostructures deposited at 90 min exhibit enhanced sensitivity to ethanol. The sensitivity of SnO2-core/ZnO-shell nanostructures towards 20 ppm ethanol gas at 400 °C is about ~5-times that of SnO2 nanowires. This improvement in ethanol gas response is attributed to high active sensing sites and the synergistic effect of the encapsulation of SnO2 by ZnO nanostructures.
    Matched MeSH terms: Ethanol/chemistry*
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