Displaying publications 61 - 80 of 108 in total

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  1. Characterisation of galloylated cyanogenic glucosides and hydrolysable tannins from leaves of Phyllagathis rotundifolia by LC-ESI-MS/MS
    Hooi Poay T, Sui Kiong L, Cheng Hock C
    Phytochem Anal, 2011 Nov-Dec;22(6):516-25.
    PMID: 21495106 DOI: 10.1002/pca.1312
    Phyllagathis rotundifolia (Jack) Bl. (Melastomataceae) is a creeping herb found in Peninsular Malaysia and Sumatra. Traditionally, a decoction of the leaves is used in the treatment of malaria, fever and stomach ache.
    Matched MeSH terms: Chemical Fractionation/methods
  2. Comparison of unmodified and modified BCR sequential extraction schemes for the fractionation of heavy metals in shrimp aquaculture sludge from Selangor, Malaysia
    Nemati K, Abu Bakar NK, Abas MR, Sobhanzadeh E, Low KH
    Environ Monit Assess, 2011 May;176(1-4):313-20.
    PMID: 20632089 DOI: 10.1007/s10661-010-1584-3
    A study was carried out to investigate the fractionation of Cd, Cr, Cu, Fe, Mn, Pb, and Zn in shrimp aquaculture sludge from Selangor, Malaysia, using original (unmodified) and modified four-steps BCR (European Community Bureau of Reference, now known as the Standards Measurements and Testing Program) sequential extraction scheme. Step 2 of the unmodified BCR procedure (subsequently called Method A) involves treatment with 0.1 M hydroxylammonium chloride at pH 2, whereas 0.5 M hydroxylammonium chloride at pH 1.5 was used in the modified BCR procedure (subsequently called Method B). Metal analyses were carried out by flame atomic absorption spectrometry. A pseudo-total aqua-regia digest of BCR CRM 701 has also been undertaken for quality assurance purposes. The recovery of Method A for all metals studied ranges from 96.14% to 105.26%, while the recovery for Method B ranges from 95.94% to 122.40%. Our results reveal that Method A underestimated the proportion of metals bound to the easily reducible fraction except for copper. Therefore, the potential mobility of these elements is higher than others. Thus, to use this sludge as a fertilizer we have to first find a remediation for reduction of heavy metal contamination.
    Matched MeSH terms: Chemical Fractionation/methods*
  3. Optimization of protein extraction for proteomic analyses of fresh and frozen "Musang King" durian pulps
    Tan XY, Misran A, Daim LDJ, Lau BYC
    Food Chem, 2021 May 01;343:128471.
    PMID: 33143964 DOI: 10.1016/j.foodchem.2020.128471
    Four different methods were evaluated to extract proteins from "Musang King" durian pulps and subsequently proteins with different abundance between fresh and long term frozen storage were identified using two-dimensional polyacrylamide gel electrophoresis coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometer analyses. The acetone-phenol method was found to produce good protein yields and gave the highest gel resolution and reproducibility. Differential protein analyses of the durian pulp revealed that 15 proteins were down-regulated and three other proteins were up-regulated after a year of frozen storage. Isoflavone reductase-like protein, S-adenosyl methionine synthase, and cysteine synthase isoform were up-regulated during frozen storage. The down-regulation of proteins in frozen durian pulps indicated that frozen storage has affected proteins in many ways, especially in their functions related to carbohydrate and energy metabolisms, cellular components, and transport processes. This study will enable future detailed investigations of proteins associated with quality attributes of durians to be studied.
    Matched MeSH terms: Chemical Fractionation/methods*
  4. Fulltext Functional expression of a novel α-amylase from Antarctic psychrotolerant fungus for baking industry and its magnetic immobilization
    He L, Mao Y, Zhang L, Wang H, Alias SA, Gao B, et al.
    BMC Biotechnol, 2017 02 28;17(1):22.
    PMID: 28245836 DOI: 10.1186/s12896-017-0343-8
    BACKGROUND: α-Amylase plays a pivotal role in a broad range of industrial processes. To meet increasing demands of biocatalytic tasks, considerable efforts have been made to isolate enzymes produced by extremophiles. However, the relevant data of α-amylases from cold-adapted fungi are still insufficient. In addition, bread quality presents a particular interest due to its high consummation. Thus developing amylases to improve textural properties could combine health benefits with good sensory properties. Furthermore, iron oxide nanoparticles provide an economical and convenient method for separation of biomacromolecules. In order to maximize the catalytic efficiency of α-amylase and support further applications, a comprehensive characterization of magnetic immobilization of α-amylase is crucial and needed.

    RESULTS: A novel α-amylase (AmyA1) containing an open reading frame of 1482 bp was cloned from Antarctic psychrotolerant fungus G. pannorum and then expressed in the newly constructed Aspergillus oryzae system. The purified recombinant AmyA1 was approximate 52 kDa. AmyA1 was optimally active at pH 5.0 and 40 °C, and retained over 20% of maximal activity at 0-20 °C. The K m and V max values toward soluble starch were 2.51 mg/mL and 8.24 × 10-2 mg/(mL min) respectively, with specific activity of 12.8 × 103 U/mg. AmyA1 presented broad substrate specificity, and the main hydrolysis products were glucose, maltose, and maltotetraose. The influence of AmyA1 on the quality of bread was further investigated. The application study shows a 26% increase in specific volume, 14.5% increase in cohesiveness and 14.1% decrease in gumminess in comparison with the control. AmyA1 was immobilized on magnetic nanoparticles and characterized. The immobilized enzyme showed improved thermostability and enhanced pH tolerance under neutral conditions. Also, magnetically immobilized AmyA1 can be easily recovered and reused for maximum utilization.

    CONCLUSIONS: A novel α-amylase (AmyA1) from Antarctic psychrotolerant fungus was cloned, heterologous expression in Aspergillus oryzae, and characterized. The detailed report of the enzymatic properties of AmyA1 gives new insights into fungal cold-adapted amylase. Application study showed potential value of AmyA1 in the food and starch fields. In addition, AmyA1 was immobilized on magnetic nanoparticles and characterized. The improved stability and longer service life of AmyA1 could potentially benefit industrial applications.

    Matched MeSH terms: Chemical Fractionation/methods
  5. Fulltext Bioassay-guided fractionation of Melastoma malabathricum Linn. leaf solid phase extraction fraction and its anticoagulant activity
    Khoo LT, Abdullah JO, Abas F, Tohit ER, Hamid M
    Molecules, 2015 Feb 24;20(3):3697-715.
    PMID: 25719740 DOI: 10.3390/molecules20033697
    The aims of this study were to examine the bioactive component(s) responsible for the anticoagulant activity of M. malabathricum Linn. leaf hot water crude extract via bioassay-guided fractionation and to evaluate the effect of bioactive component(s) on the intrinsic blood coagulation pathway. The active anticoagulant fraction of F3 was subjected to a series of chromatographic separation and spectroscopic analyses. Furthermore, the effect of the bioactive component(s) on the intrinsic blood coagulation pathway was studied through immediate and time incubation mixing studies. Through Activated Partial Thromboplastin Time (APTT) assay-guided fractionation, Subfraction B was considered the most potent anticoagulant fraction. Characterisation of Subfraction B indicated that anticoagulant activity could partly be due to the presence of cinnamic acid and a cinnamic acid derivative. APTT assays for both the immediate and time incubation mixing were corrected back into normal clotting time range (35.4-56.3 s). In conclusion, cinnamic acid and cinnamic acid derivative from Subfraction B were the first such compounds to be discovered from M. malabathricum Linn. leaf hot water crude extract that possess anticoagulant activity. This active anticoagulant Subfraction B prolonged blood clotting time by causing factor(s) deficiency in the intrinsic blood coagulation pathway.
    Matched MeSH terms: Chemical Fractionation
  6. Fractionation of oil palm frond hemicelluloses by water or alkaline impregnation and steam explosion
    Sabiha-Hanim S, Mohd Noor MA, Rosma A
    Carbohydr Polym, 2015 Jan 22;115:533-9.
    PMID: 25439929 DOI: 10.1016/j.carbpol.2014.08.087
    Steam explosion of oil palm frond has been carried out under different temperatures between 180 and 210°C for 4 min (severity of 2.96-3.84) after impregnation of the frond chips with water or KOH solution. The effects of impregnation and steam explosion conditions of oil palm fronds on the water soluble fraction and insoluble fraction were investigated. The maximum yield of hemicelluloses in water soluble fractions recovered was 23.49% and 25.33% for water and KOH impregnation, treated with steam explosion at temperature of 210°C (severity of 3.84) with a fractionation efficiency of 77.30% and 83.32%, respectively. Under this condition, the water insoluble fractions contained celluloses at 60.83% and 64.80% for water and KOH impregnation, respectively. The steam explosion temperature of 210°C for 4 min (logR(o) 3.84) was found to be the best condition in the extraction of hemicelluloses from OPF for both types of impregnation.
    Matched MeSH terms: Chemical Fractionation
  7. Advanced analytical techniques for the extraction and characterization of plant-derived essential oils by gas chromatography with mass spectrometry
    Waseem R, Low KH
    J Sep Sci, 2015 Feb;38(3):483-501.
    PMID: 25403494 DOI: 10.1002/jssc.201400724
    In recent years, essential oils have received a growing interest because of the positive health effects of their novel characteristics such as antibacterial, antifungal, and antioxidant activities. For the extraction of plant-derived essential oils, there is the need of advanced analytical techniques and innovative methodologies. An exhaustive study of hydrodistillation, supercritical fluid extraction, ultrasound- and microwave-assisted extraction, solid-phase microextraction, pressurized liquid extraction, pressurized hot water extraction, liquid-liquid extraction, liquid-phase microextraction, matrix solid-phase dispersion, and gas chromatography (one- and two-dimensional) hyphenated with mass spectrometry for the extraction through various plant species and analysis of essential oils has been provided in this review. Essential oils are composed of mainly terpenes and terpenoids with low-molecular-weight aromatic and aliphatic constituents that are particularly important for public health.
    Matched MeSH terms: Chemical Fractionation
  8. The effect of the labile organic fraction in food waste and the substrate/inoculum ratio on anaerobic digestion for a reliable methane yield
    Kawai M, Nagao N, Tajima N, Niwa C, Matsuyama T, Toda T
    Bioresour Technol, 2014 Apr;157:174-80.
    PMID: 24556370 DOI: 10.1016/j.biortech.2014.01.018
    Influence of the labile organic fraction (LOF) on anaerobic digestion of food waste was investigated in different S/I ratio of 0.33, 0.5, 1.0, 2.0 and 4.0g-VSsubstrate/g-VSinoculum. Two types of substrate, standard food waste (Substrate 1) and standard food waste with the supernatant (containing LOF) removed (Substrate 2) were used. Highest methane yield of 435ml-CH4g-VS(-1) in Substrate 1 was observed in the lowest S/I ratio, while the methane yield of the other S/I ratios were 38-73% lower than the highest yield due to acidification. The methane yields in Substrate 2 were relatively stable in all S/I conditions, although the maximum methane yield was low compared with Substrate 1. These results showed that LOF in food waste causes acidification, but also contributes to high methane yields, suggesting that low S/I ratio (<0.33) is required to obtain a reliable methane yield from food waste compared to other organic substrates.
    Matched MeSH terms: Chemical Fractionation
  9. Fulltext Detoxification of toxic phorbol esters from Malaysian Jatropha curcas Linn. kernel by Trichoderma spp. and endophytic fungi
    Najjar A, Abdullah N, Saad WZ, Ahmad S, Oskoueian E, Abas F, et al.
    Int J Mol Sci, 2014;15(2):2274-88.
    PMID: 24504029 DOI: 10.3390/ijms15022274
    The presence of phorbol esters (PEs) with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fungi (Trichoderma harzianum JQ350879.1, T. harzianum JQ517493.1, Paecilomyces sinensis JQ350881.1, Cladosporium cladosporioides JQ517491.1, Fusarium chlamydosporum JQ350882.1, F. chlamydosporum JQ517492.1 and F. chlamydosporum JQ350880.1) was conducted by fermentation in broth cultures. The PEs were detected by liquid chromatography-diode array detector-electrospray ionization mass spectrometry (LC-DAD-ESIMS) and quantitatively monitored by HPLC using phorbol-12-myristate 13-acetate as the standard. At day 30 of incubation, two T. harzianum spp., P. sinensis and C. cladosporioides significantly (p < 0.05) removed PEs with percentage losses of 96.9%-99.7%, while F. chlamydosporum strains showed percentage losses of 88.9%-92.2%. All fungal strains could utilize the PEs-rich fraction for growth. In the cytotoxicity assay, cell viabilities of Chang liver and NIH 3T3 fibroblast cell lines were less than 1% with the untreated PEs-rich fraction, but 84.3%-96.5% with the fungal treated PEs-rich fraction. There was no inhibition on cell viability for normal fungal growth supernatants. To conclude, Trichoderma spp., Paecilomyces sp. and Cladosporium sp. are potential microbes for the detoxification of PEs.
    Matched MeSH terms: Chemical Fractionation
  10. Fulltext Optimization of extraction parameters by using response surface methodology, purification, and identification of anthocyanin pigments in Melastoma malabathricum fruit
    Anuar N, Mohd Adnan AF, Saat N, Aziz N, Mat Taha R
    ScientificWorldJournal, 2013;2013:810547.
    PMID: 24174918 DOI: 10.1155/2013/810547
    Anthocyanins not just have various benefits in food industry but also have been used as natural colourants in cosmetic, coating products and as potential natural photosensitizers in solar cell. Thus, the main purpose of this study was to obtain information on the maximum yield of anthocyanin that can be recovered from Melastoma malabathricum fruit. Factors such as extraction temperature, extraction time, and solid to liquid ratio were identified to be significantly affecting anthocyanin extraction efficiency. By using three-level three-factor Box-Behnken design, the optimized conditions for anthocyanin extraction by acidified methanol (R (2) = 0.972) were temperature of 60°C, time of 86.82 min, and 0.5 : 35 (g/mL) solid to liquid ratio while the optimum extraction conditions by acidified ethanol (R (2) = 0.954) were temperature of 60°C, time of 120 min, and 0.5 : 23.06 (g/mL) solid to liquid ratio. The crude anthocyanin extract was further purified by using Amberlite XAD-7 and Sephadex LH-20 column chromatography. Identification of anthocyanins revealed the presence of cyanidin dihexoside, cyanidin hexoside, and delphinidin hexoside as the main anthocyanins in M. malabathricum fruit.
    Matched MeSH terms: Chemical Fractionation
  11. An assessment of three noncommercial DNA extraction methods from dried blood spots for beta-thalassaemia mutation identification
    Karthipan SN, George E, Jameela S, Lim WF, Teh LK, Lee TY, et al.
    Int J Lab Hematol, 2011 Oct;33(5):540-4.
    PMID: 21884505 DOI: 10.1111/j.1751-553X.2011.01304.x
    Dried blood spots (DBS) are currently the recommended sample collection method for newborn screening programmes in America. Early diagnosis of beta-thalassaemia screening is essential as it provides an added advantage especially in sickle cell disease. Beta-thalassaemia frequency is high in many poor countries, and the cost of using commercial DNA extraction kits can be prohibitive. Our study assessed three methods that use minimal reagents and materials to extract DNA from DBS for beta-thalassaemia identification.
    Matched MeSH terms: Chemical Fractionation
  12. Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production
    Sabiha-Hanim S, Noor MA, Rosma A
    Bioresour Technol, 2011 Jan;102(2):1234-9.
    PMID: 20797853 DOI: 10.1016/j.biortech.2010.08.017
    Oil palm (Elaeis guineensis Jacq.) is one of the most important commercial crops for the production of palm oil, which generates 10.88 tons of oil palm fronds per hectare of plantation as a by-product. In this study, oil palm frond fibres were subjected to an autohydrolysis treatment using an autoclave, operated at 121 °C for 20-80 min, to facilitate the separation of hemicelluloses. The hemicellulose-rich solution (autohydrolysate) was subjected to further hydrolysis with 4-16 U of mixed Trichoderma viride endo-(1,4)-β-xylanases (EC 3.2.1.8) per 100 mg of autohydrolysate. Autoclaving of palm fronds at 121°C for 60 min (a severity factor of 2.40) recovered 75% of the solid residue, containing 57.9% cellulose and 18% Klason lignin, and an autohydrolysate containing 14.94% hemicellulose, with a fractionation efficiency of 49.20%. Subsequent enzymatic hydrolysis of the autohydrolysate with 8 U of endoxylanase at 40 °C for 24 h produced a solution containing 17.5% xylooligosaccharides and 25.6% xylose. The results clearly indicate the potential utilization of oil palm frond, an abundantly available lignocellulosic biomass for the production of xylose and xylooligosaccharides which can serve as functional food ingredients.
    Matched MeSH terms: Chemical Fractionation
  13. Characterization of low saturation palm oil products after continuous enzymatic interesterification and dry fractionation
    Huey SM, Hock CC, Lin SW
    J Food Sci, 2009 May-Jul;74(4):E177-83.
    PMID: 19490322 DOI: 10.1111/j.1750-3841.2009.01122.x
    The lipase-catalyzed interesterification of refined, bleached, deodorized palm olein with iodine value (IV) of 62 was studied in a pilot continuous packed-bed reactor operating at 65 degrees C. Sn-1,3 specific immobilized enzyme; Lipozyme TL IM (Thermomyces Lanuginosa) from Novozyme A/S was used in this study. The interesterification reaction produced fully solidified fats at ambient temperature due to the production of trisaturated triacylglycerols (TAG) (PPP and PPS, where P = palmitic acid, S = stearic acid). The reaction also increased the percentage of triunsaturated TAG (OLL, OLO, and OOO, where O = oleic acid, L = linoleic acid). The interesterified product was then dry fractionated at temperatures of 9, 12, 15, 18, and 21 degrees C to separate the saturated fats from the unsaturated. The results show that IV of olein increased when the fractionation temperature (T(FN)) decreased. The highest IV of olein was 72, obtained from T(FN) at 9 degrees C. After interesterification and laboratory-scale fractionation, the olein fractions contained higher unsaturation content ranging from 64.7% to 67.7% compared to the starting material (58.3%), while the saturation content was reduced from 41.7% to the range of 32.3% to 35.3%. The yields of these oleins were low with the range of 24.8% to 51.8% due to the limitation of the vacuum filtration. Ten kilograms of pilot-scale fractionation with membrane press filter was used to determine the exact olein yield. At T(FN) of 12 degrees C, 67.1% of olein with saturation content of 33.9% was obtained.
    Matched MeSH terms: Chemical Fractionation
  14. Properties of high-oleic palm oils derived by fractional crystallization
    Ramli MR, Siew WL, Cheah KY
    J Food Sci, 2008 Apr;73(3):C140-5.
    PMID: 18387090 DOI: 10.1111/j.1750-3841.2007.00657.x
    High-oleic palm oil (HOPO) with an oleic acid content of 59.0% and an iodine value (IV) of 78.2 was crystallized in a 200-kg De Smet crystallizer with a predetermined cooling program and appropriate agitation. The slurry was then fractionated by means of dry fractionation at 4, 8, 10, 12, and 15 degrees C. The oil and the fractionated products were subjected to physical and chemical analyses, including fatty acid composition, triacylglycerol and diacylglycerol composition, solid fat content, cloud point, slip melting point, and cold stability test. Fractionation at 15 degrees C resulted in the highest olein yield but with minimal oleic acid content. Due to the enhanced unsaturation of the oil, fractionation at relatively lower crystallization temperature showed a considerable effect on fatty acid composition as well as triacylglycerol and diacylglycerol composition of liquid fractions compared to higher crystallization temperature. The olein and stearin fractionated at 4 degrees C had the best cold stability at 0 degrees C and sharper melting profile, respectively.
    Matched MeSH terms: Chemical Fractionation
  15. Enzyme-assisted extraction and identification of antioxidative and α-amylase inhibitory peptides from Pinto beans (Phaseolus vulgaris cv. Pinto)
    Ngoh YY, Gan CY
    Food Chem, 2016 Jan 1;190:331-7.
    PMID: 26212978 DOI: 10.1016/j.foodchem.2015.05.120
    Antioxidant and α-amylase inhibitor peptides were successfully extracted from Pinto bean protein isolate (PBPI) using Protamex. A factorial design experiment was conducted and the effects of extraction time, pH and temperature were studied. pH 7.5, extraction time of 1h, S/E ratio of 10 (w/w) and temperature of 50 °C gave the highest antioxidant activities (i.e., ABTS scavenging activity (53.3%) and FRAP value (3.71 mM)), whereas pH 6.5 with the same extraction time, S/E ratio and temperature, gave the highest α-amylase inhibitory activity (57.5%). It was then fractioned using membrane ultrafiltration with molecular weight cutoffs of 100, 50, 30, 10 and 3 kDa. Peptide fraction <3 kDa, which exhibited the highest antioxidant activities (i.e., ABTS (42.2%) and FRAP (0.81 mM)) and α-amylase inhibitory activity (62.1%), was then subjected to LCMS and MS/MS analyses. Six sequences were identified for antioxidant peptides, whereas seven peptides for α-amylase inhibitor.
    Matched MeSH terms: Chemical Fractionation
  16. Effect of co-fractionation technique in the preparation of palm oil and sal fat based cocoa butter equivalent
    Md Ali AR
    Int J Food Sci Nutr, 1996 Jan;47(1):15-22.
    PMID: 8616668
    Two types of palm oil and sal fat based cocoa butter equivalents, namely fCBE (produced by using co-fractionation method) and mCBE (produced by using conventional method) were prepared. Results showed that the fCBE had triglyceride composition and solidification characteristics closer to the Malaysian cocoa butter than the mCBE produced at the same yield percentage. Increasing acetone washing time had little effect on the fCBE if compared to the effect of increasing palm olein to sal fat blend ratio. Co-fractionation technique increase the compatibility between CBE component triglycerides. Thus, more palm oil can be incorporated in the preparation and the process can be carried out at not low temperature as compared to the conventional method.
    Matched MeSH terms: Chemical Fractionation
  17. Recent Developments of Reverse Micellar Techniques for Lysozyme, Bovine Serum Albumin, and Bromelain Extraction
    Chia SR, Tang MSY, Chow YH, Ooi CW, Rambabu K, Zhu L, et al.
    Mol Biotechnol, 2019 Oct;61(10):715-724.
    PMID: 31350687 DOI: 10.1007/s12033-019-00200-7
    Biomolecules produced by living organisms can perform vast array of functions and play an important role in the cell. Important biomolecules such as lysozyme, bovine serum albumin (BSA), and bromelain are often studied by researchers due to their beneficial properties. The application of reverse micelles is an effective tool for protein separation from their sources due to the special system structure. Mechanisms of transferring biomolecules and factors that influence the extraction of biomolecules are reviewed in this paper. The enhancement of biomolecule extraction could be achieved depending on the properties of reverse micelles. This paper provides an overall review on lysozyme, BSA, and bromelain extraction by reverse micelle for various applications.
    Matched MeSH terms: Chemical Fractionation
  18. Review on rosmarinic acid extraction, fractionation and its anti-diabetic potential
    Ngo YL, Lau CH, Chua LS
    Food Chem Toxicol, 2018 Nov;121:687-700.
    PMID: 30273632 DOI: 10.1016/j.fct.2018.09.064
    Rosmarinic acid is a bioactive phytochemical that can be found in many herbs as ethnomedicines. It possesses remarkable pharmacological activities, and thus leading to its exploration as a therapeutic drug in diabetes treatment recently. This article reviews the extraction and fractionation techniques for plant-based natural rosmarinic acid and its anti-diabetic potential based on literature data published in journals, books, and patents from 1958 to 2017. Factors affecting the performance of rosmarinic acid extraction and fractionation such as operating temperature, time, solvent to sample ratio and eluent system are compiled and discussed in detail. The inhibitory action of rosmarinic acid against sugar digestive enzymes, and protective action towards pancreatic β-cell dysfunction and glucolipotoxicity mediated oxidative stress are also critically reviewed. The optimal parameters are largely dependent on the applied extraction and fractionation techniques, as well as the nature of plant samples. Previous studies have proven the potent role of rosmarinic acid to control plasma glucose level and increase insulin sensitivity in hyperglycemia. Although rosmarinic acid is readily absorbed by human body, its mechanism after consumption is remained unclear. Intensive studies should be well planned to determine the dosage and toxicity level of rosmarinic acid for efficacy and safe consumption.
    Matched MeSH terms: Chemical Fractionation
  19. An effective placental cotyledons proteins extraction method for 2D gel electrophoresis
    Tan NJ, Daim LD, Jamil AA, Mohtarrudin N, Thilakavathy K
    Electrophoresis, 2017 03;38(5):633-644.
    PMID: 27992069 DOI: 10.1002/elps.201600377
    Effective protein extraction is essential especially in producing a well-resolved proteome on 2D gels. A well-resolved placental cotyledon proteome, with good reproducibility, have allowed researchers to study the proteins underlying the physiology and pathophysiology of pregnancy. The aim of this study is to determine the best protein extraction protocol for the extraction of protein from placental cotyledons tissues for a two-dimensional gel electrophoresis (2D-GE). Based on widely used protein extraction strategies, 12 different extraction methodologies were carefully selected, which included one chemical extraction, two mechanical extraction coupled protein precipitations, and nine chemical extraction coupled protein precipitations. Extracted proteins were resolved in a one-dimensional gel electrophoresis and 2D-GE; then, it was compared with set criteria: extraction efficacy, protein resolution, reproducibility, and recovery efficiency. Our results revealed that a better profile was obtained by chemical extraction in comparison to mechanical extraction. We further compared chemical extraction coupled protein precipitation methodologies, where the DNase/lithium chloride-dense sucrose homogenization coupled dichloromethane-methanol precipitation (DNase/LiCl-DSH-D/MPE) method showed good protein extraction efficiency. This, however, was carried out with the best protein resolution and proteome reproducibility on 2D-gels. DNase/LiCl-DSH-D/MPE was efficient in the extraction of proteins from placental cotyledons tissues. In addition, this methodology could hypothetically allow the protein extraction of any tissue that contains highly abundant lipid and glycogen.
    Matched MeSH terms: Chemical Fractionation
  20. Fulltext Preparation of Lignan-Rich Extract from the Aerial Parts of Phyllanthus niruri Using Nonconventional Methods
    Meselhy MR, Abdel-Sattar OE, El-Mekkawy S, El-Desoky AM, Mohamed SO, Mohsen SM, et al.
    Molecules, 2020 Mar 05;25(5).
    PMID: 32151037 DOI: 10.3390/molecules25051179
    Phyllanthin and related lignans were found to be responsible, at least in part, for most of the activity of Phyllanthus species. This observation encouraged the authors to develop methods for the preparation of an extract rich in phyllanthin and related lignans from the aerial parts of P. niruri L. Direct extraction with solvents produced extracts with variable yields and contents of lignans. Lignans were identified by LC-ESI-MS analysis as phyllanthin (used as marker substance), hypophyllanthin, phylltetralin, nirtetralin, and niranthin. Extraction with boiling water produced 18.10 g% (w/w) extract with a trace amount of lignans (phyllanthin content of 0.33 ± 0.10 mg/g extract), while extraction with MeOH gave 3.6 g% w/w extract with a low phyllanthin content (3.1 mg/g extract), as determined by HPLC. However, Soxhlet extraction with hexane, CH2Cl2, or acetone gave extracts with low yields (0.82, 1.12, and 3.40 g% w/w, respectively) and a higher phyllanthin contents (36.2 ± 2.6, 11.7 ± 1.68, and 11.7 ± 1.10 mg/g extract, respectively). Extraction quality and efficiency were optimized by adopting the following three different approaches: (1) Alkaline digestion of the plant material with 30% potassium hydroxide yielded 3.1 g% w/w of purified extract with high phyllanthin content (22.34 ± 0.13 mg/g); (2) microwave-assisted extraction using 80% MeOH gave an extract with a better yield (8.13 g% w/w) and phyllanthin content (21.2 ± 1.30 mg/g) (after filtration through a Diaion HP-20 column); and (3) treatment of the ground plant material at 50 °C with two hydrolytic enzymes, cellulase (9 U/g for 12 h) and then, protease (4 U/g up to 72 h) optimized the yield of extract (13.92 g% w/w) and phyllanthin content (25.9 mg/g extract and total lignans content of 85.87 mg/g extract). In conclusion, the nonconventional methods presented here are superior for optimizing the yield of extract and its lignan contents from the aerial parts of P. niruri.
    Matched MeSH terms: Chemical Fractionation
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