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Fulltext Detection of Lard in Cocoa Butter-Its Fatty Acid Composition, Triacylglycerol Profiles, and Thermal Characteristics

Azir M, Abbasiliasi S, Tengku Ibrahim TA, Manaf YNA, Sazili AQ, Mustafa S

Foods, 2017 Nov 09;6(11).
PMID: 29120362 DOI: 10.3390/foods6110098

The present study investigates the detection of lard in cocoa butter through changes in fatty acids composition, triacylglycerols profile, and thermal characteristics. Cocoa butter was mixed with 1% to 30% (v/v) of lard and analyzed using a gas chromatography flame ionization detector, high performance liquid chromatography, and differential scanning calorimetry. The results revealed that the mixing of lard in cocoa butter showed an increased amount of oleic acid in the cocoa butter while there was a decrease in the amount of palmitic acid and stearic acids. The amount of POS, SOS, and POP also decreased with the addition of lard. A heating thermogram from the DSC analysis showed that as the concentration of lard increased from 3% to 30%, two minor peaks at -26 °C and 34.5 °C started to appear and a minor peak at 34.5 °C gradually overlapped with the neighbouring major peak. A cooling thermogram of the above adulterated cocoa butter showed a minor peak shift to a lower temperature of -36 °C to -41.5 °C. Values from this study could be used as a basis for the identification of lard from other fats in the food authentication process.

Matched MeSH terms: Chromatography, Gas; Chromatography, High Pressure Liquid
Ganglioside Composition in Beef, Chicken, Pork, and Fish Determined Using Liquid Chromatography-High-Resolution Mass Spectrometry

Fong BY, Ma L, Khor GL, van der Does Y, Rowan A, McJarrow P, et al.

J Agric Food Chem, 2016 Aug 17;64(32):6295-305.
PMID: 27436425 DOI: 10.1021/acs.jafc.6b02200

Gangliosides (GA) are found in animal tissues and fluids, such as blood and milk. These sialo-glycosphingolipids have bioactivities in neural development, the gastrointestinal tract, and the immune system. In this study, a high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was validated to characterize and quantitate the GA in beef, chicken, pork, and fish species (turbot, snapper, king salmon, and island mackerel). For the first time, we report the concentration of GM3, the dominant GA in these foods, as ranging from 0.35 to 1.1 mg/100 g and 0.70 to 5.86 mg/100 g of meat and fish, respectively. The minor GAs measured were GD3, GD1a, GD1b, and GT1b. Molecular species distribution revealed that the GA contained long- to very-long-chain acyl fatty acids attached to the ceramide moiety. Fish GA contained only N-acetylneuraminic acid (NeuAc) sialic acid, while beef, chicken, and pork contained GD1a/b species that incorporated both NeuAc and N-glycolylneuraminic acid (NeuGc) and hydroxylated fatty acids.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
GC-MS and HPLC profiles of phenolic fractions of the leaf of Telfairia occidentalis

Eseyin OA, Sattar MA, Rathore HA, Aigbe F, Afzal S, Ahmad A, et al.

Pak J Pharm Sci, 2018 Jan;31(1):45-50.
PMID: 29348083

Telfairia occidentalis possesses high antioxidant activity. However, the antioxidant components of the plant have not yet been identified. This study was undertaken to identify the phenolics in the leaf of the plant. Extract and fractions of the leaf of the plant were analysed using the HPLC and GCMS. HPLC analysis revealed the presence of gallic acid (22.19μg/mg), catechin (29.17μg/mg), caffeic acid (9.17μg/mg), ferulic acid (0.94μg/mg), sinapic acid (1.91 μg/mg) and 4-hydroxy benzoic acid (43.86 μg/mg) in the aqueous extract. Phenolics fraction contained gallic acid (0.88 μg/mg), catechin (2.70μg/mg), caffeic acid (7.92μg/mg), ferulic acid (2.72μg/mg), benzoic acid (6.36μg/mg), p-coumaric acid (1.48μg/mg), quercetin (12.00μg/mg). Only caffeic acid (2.50μg/mg), ferulic acid (0.44μg/mg) and quercetin (8.50μg/mg) were detected in the flavonoid fraction. While GCMS analysis showed the presence of methylparaben; ethylparaben; benzoic acid; 4-hydroxy-2-methoxy-3,5,6-trimethyl-, methyl ester; 4-hydroxy-3-methoxy; phenol, 5-methoxy-2-(methoxymethyl)-; phenol, 5-methoxy-2, 3- dimethyl; and phenol, 2-(2-benzothiazolyl)-. This study is the first to reveal the identity of some phenolics components of the leaf of Telfairia occidentalis.

Matched MeSH terms: Chromatography, High Pressure Liquid; Gas Chromatography-Mass Spectrometry
Effect directed analysis of bioactive compounds in leaf extracts from two Salvia species by High-performance thin-layer chromatography

Agatonovic-Kustrin S, Wong S, Dolzhenko AV, Gegechkori V, Ku H, Tan WK, et al.

J Pharm Biomed Anal, 2023 Apr 01;227:115308.
PMID: 36827737 DOI: 10.1016/j.jpba.2023.115308

Extracts of two Salvia species, Salvia apiana (white sage) and Salvia officinalis (common sage) were screened for phytoconstituents with the ability to act as antidiabetic, cognitive enhancing, or antimicrobial agents, by hyphenation of high-performance thin-layer chromatography with enzymatic and microbial effect directed assays. Two bioactive zones with α-amylase inhibition (zone 1 and zone 2), 3 zones for acetylcholinesterase inhibition (zones 3, 4 and 5), and two zones for antimicrobial activity (zones 4 and 5) were detected. The compounds from the five bioactive zones were initially identified by coelution with standards and comparing the RF values of standards to the bioautograms. Identity was confirmed with ATR-FTIR spectra of the isolated compounds from the bioactive zones. A significantly higher α-amylase and acetylcholinesterase inhibition of S. apiana leaf extract was associated with a higher flavonoid and diterpenoid content. Fermented S. officinalis extract exhibited a significantly higher ability to inhibit α-amylase compared to other non-fermented extracts from this species, due to increased extraction of flavonoids. The ATR-FTIR spectra of 2 zones with α-amylase inhibition, indicated that flavonoids and phenolic acids were responsible for α-amylase inhibition. Multiple zones of acetylcholinesterase inhibition were related to the presence of phenolic abietane diterpenoids and triterpenoid acids. The presence of abietane diterpenoids and triterpenoid acids was also found responsible for the mild antimicrobial activity. Flash chromatography was used to isolate sufficient amounts of bioactive compounds for further characterisation via NMR and MS spectroscopy. Five compounds were assigned to the zones where bioactivity was observed: cirsimaritin (zone 1), a caffeic acid polymer (zone 2), 16-hydroxyrosmanol (zone 3), 16-hydroxycarnosic acid (zone 4), oleanolic and ursolic acids (zone 5).

Matched MeSH terms: Chromatography, Thin Layer/methods
Determination of biogenic amines in chicken, beef, and mutton by dansyl chloride microwave derivatization in Malaysia

Yue CS, Lim AK, Chia ML, Wong PY, Chin JSR, Wong WH

J Food Sci, 2023 Feb;88(2):650-665.
PMID: 36624628 DOI: 10.1111/1750-3841.16404

In this study, an improved dansyl-chloride derivatization technique using a microwave synthesizer was used for the qualitative and quantitative analyses of biogenic amine in the fresh meat samples. The derivatization technique was optimized in terms of temperature, reaction time, and spinning speed. The derivatization method together with a validated reversed-phase HPLC-DAD method was used for the determination of biogenic amines in chicken, beef, and mutton sold in the wet market. The results of the analyses showed that tryptamine, putrescine, and histamine were generally detected in all the three types of meat. Higher levels of histamine were found in chicken and beef. However, low levels of histamine were observed in mutton. Tyramine was either detected low or moderate in all the three types of meat. The biogenic amines of the fresh meat sold in the wet market is generally higher than the reported values. The mechanisms of biogenic amines-dansyl-chloride formation were investigated and proposed. PRACTICAL APPLICATION: The biogenic amine derivatization method was improved. The improved derivatization method can be potentially used for various food products beside meats for routine biogenic amine analyses due to its fast analysis time and simplicity. High levels of biogenic amines were generally found in the meat sold in the wet markets. However, proper handling of the raw meat can reduce the risk of infection.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods
Fulltext Classification of Raw Stingless Bee Honeys by Bee Species Origins Using the NMR- and LC-MS-Based Metabolomics Approach

Razali MTA, Zainal ZA, Maulidiani M, Shaari K, Zamri Z, Mohd Idrus MZ, et al.

Molecules, 2018 Aug 28;23(9).
PMID: 30154302 DOI: 10.3390/molecules23092160

The official standard for quality control of honey is currently based on physicochemical properties. However, this method is time-consuming, cost intensive, and does not lead to information on the originality of honey. This study aims to classify raw stingless bee honeys by bee species origins as a potential classifier using the NMR-LCMS-based metabolomics approach. Raw stingless bee honeys were analysed and classified by bee species origins using proton nuclear magnetic resonance (¹H-NMR) spectroscopy and an ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-QTOF MS) in combination with chemometrics tools. The honey samples were able to be classified into three different groups based on the bee species origins of Heterotrigona itama, Geniotrigona thoracica, and Tetrigona apicalis. d-Fructofuranose (H. itama honey), β-d-Glucose, d-Xylose, α-d-Glucose (G. thoracica honey), and l-Lactic acid, Acetic acid, l-Alanine (T. apicalis honey) ident d-Fructofuranose identified via ¹H-NMR data and the diagnostic ions of UHPLC-QTOF MS were characterized as the discriminant metabolites or putative chemical markers. It could be suggested that the quality of honey in terms of originality and purity can be rapidly determined using the classification technique by bee species origins via the ¹H-NMR- and UHPLC-QTOF MS-based metabolomics approach.

Matched MeSH terms: Chromatography, Liquid*
Quality by Design-based RP-HPLC Method for Estimation of Curcumin in Rat Plasma and Fecal Microbiota Extract-based Solid Self-nano Emulsifying Drug Delivery System

Corrie L, Gulati M, Kaur J, Awasthi A, Vishwas S, Ramanunny AK, et al.

Curr Drug Res Rev, 2023;15(3):272-285.
PMID: 36683365 DOI: 10.2174/2589977515666230120140543

BACKGROUND: Curcumin (CRM) is known to possess various therapeutic properties, such as anti-inflammatory and antidiabetic properties, and is, therefore, considered to be an effective therapeutic.
OBJECTIVE: A sensitive method for the estimation of CRM in plasma, as well as fecal matter-based solid self-nano emulsifying drug delivery system (S-SNEDDS), has been reported for the first time.
METHODS: A bioanalytical method was optimized using Box-Behnken Design having 13 runs and 3 responses. The optimized method was developed using methanol and water (70:30 v/v) with a flow rate of 1 mL/min. Quercetin was used as an internal standard. A specificity test was also performed for the developed CRM solid self-nano emulsifying drug delivery system.
RESULTS: The retention time of CRM was found to be 14.18 minutes. The developed method was validated and found to be linear in the range of 50-250 ng/mL with an R2 of 0.999. Accuracy studies indicated that CRM had a percentage recovery of less than 105% and more than 95%, respectively. Precision studies were carried out for inter, intraday, and inter-analyst precision, and the %RSD was found to be less than 2%. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 3.37 ng/mL and 10.23 ng/mL, respectively. Stability studies for shortterm, long term and freeze-thaw cycles showed a %RSD of less than 2%, indicating the stability of CRM in the plasma matrix. Moreover, the blank fecal microbiota extract slurry did not show any peak at the retention time of CRM in a CRM-loaded solid nanoemulsifying drug delivery system containing fecal microbiota extract indicating its specificity.
CONCLUSION: Hence, the developed method can have clinical implications as it helps estimate CRM in blood samples and also provides a simple and sensitive method for the estimation of plant-based flavonoids along with fecal microbiota extract formulations.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods
Fulltext Recent progress in mass spectrometry-based strategies for elucidating protein-protein interactions

Low TY, Syafruddin SE, Mohtar MA, Vellaichamy A, A Rahman NS, Pung YF, et al.

Cell Mol Life Sci, 2021 Jul;78(13):5325-5339.
PMID: 34046695 DOI: 10.1007/s00018-021-03856-0

Protein-protein interactions are fundamental to various aspects of cell biology with many protein complexes participating in numerous fundamental biological processes such as transcription, translation and cell cycle. MS-based proteomics techniques are routinely applied for characterising the interactome, such as affinity purification coupled to mass spectrometry that has been used to selectively enrich and identify interacting partners of a bait protein. In recent years, many orthogonal MS-based techniques and approaches have surfaced including proximity-dependent labelling of neighbouring proteins, chemical cross-linking of two interacting proteins, as well as inferring PPIs from the co-behaviour of proteins such as the co-fractionating profiles and the thermal solubility profiles of proteins. This review discusses the underlying principles, advantages, limitations and experimental considerations of these emerging techniques. In addition, a brief account on how MS-based techniques are used to investigate the structural and functional properties of protein complexes, including their topology, stoichiometry, copy number and dynamics, are discussed.

Matched MeSH terms: Chromatography, Affinity/methods*
Determination of flavonoids from Orthosiphon stamineus in plasma using a simple HPLC method with ultraviolet detection

Loon YH, Wong JW, Yap SP, Yuen KH

J Chromatogr B Analyt Technol Biomed Life Sci, 2005 Feb 25;816(1-2):161-6.
PMID: 15664346

A simple liquid chromatographic method was developed for the simultaneous determination of flavonoids from Orthosiphon stamineus Benth, namely sinensitin, eupatorin and 3'-hydroxy-5,6,7,4'-tetramethoxyflavone, in plasma. Prior to analysis, the flavonoids and the internal standard (naproxen) were extracted from plasma samples using a 1:1 mixture of ethyl acetate and chloroform. The detection and quantification limits for the three flavonoids were similar being 3 and 5 ng/ml, respectively. The within-day and between-day accuracy values, expressed as percentage of true values, for the three flavonoids were between 95 and 107%, while the corresponding precision, expressed as coefficients of variation, for the three flavonoids were less than 14%. In addition, the mean recovery values of the extraction procedure for all the flavonoids were between 92 and 114%. The calibration curves were linear over a concentration range of 5-4000 ng/ml. The present method was applied to analyse plasma samples obtained from a pilot study using rats in which the mean absolute oral bioavailability values for sinensitin, eupatorin and 3'-hydroxy-5,6,7,4'-tetramethoxyflavone was 9.4, 1.0 and 1.5%, respectively.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods
Determination of plasma testosterone using a simple liquid chromatographic method

Ng BH, Yuen KH

J Chromatogr B Analyt Technol Biomed Life Sci, 2003 Aug 15;793(2):421-6.
PMID: 12906917

A simple and sensitive high-performance liquid chromatographic (HPLC) method using ultraviolet detection was developed for the determination of testosterone in human plasma. Testosterone and the internal standard, griseofulvin, were extracted from 0.50 ml plasma sample using a mixture of dichloromethane-2,2,4-trimethylpentane (3:2, v/v). The mobile phase, consisted of 0.02 M sodium dihydrogenphosphate-acetonitrile-methanol (51:47:2, v/v) adjusted to pH 3.1 and delivered to a C(18) analytical column (150 x 4.6 mm I.D., 4 microm particles) at a flow-rate of 1 ml/min while the detection wavelength was set at 240 nm with a sensitivity range of 0.005 a.u.f.s. The method has a quantification limit of 1.6 ng/ml. Recoveries of testosterone were all greater than 92% over the linear concentration range of 1.6-400 ng/ml while that of griseofulvin was approximately 95%. The within- and between-day RSD values were all less than 8% while the accuracy values ranged from 96.0 to 106.0% over the concentration range studied. The method was applied to the analysis of early morning plasma testosterone levels of 12 healthy human male volunteers. The levels were found to range from 3.1 to 8.4 ng/ml, within the normal range reported in the literature.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
Simple liquid chromatographic method for the determination of cefotaxime in human and rat plasma

Ling SS, Yuen KH, Barker SA

J Chromatogr B Analyt Technol Biomed Life Sci, 2003 Jan 05;783(1):297-301.
PMID: 12450550

A high-performance liquid chromatographic method with ultraviolet (UV) detection was developed for measuring cefotaxime in rat and human plasma. The method used direct injection of the plasma supernatant after deproteinization with 70% perchloric acid. Degradation of cefotaxime in acidic medium was retarded by adding phosphate buffer before centrifuging the sample. The mobile phase was 0.05 M aqueous ammonium acetate-acetonitrile-tetrahydrofuran (87:11:2, v/v) adjusted to pH 5.5. Analysis was run at a flow-rate of 1.0 ml/min, and a detection wavelength of 254 nm was used. The method has a quantification limit of 0.20 microgram/ml. The within- and between-day coefficients of variation and accuracy values were less than 8% and +/-3%, respectively, while the recovery values were greater than 87% over the concentration range tested (0.20-50 microgram/ml). The speed, sensitivity, specificity and reproducibility of this method make it particularly suitable for the routine determination of cefotaxime in human plasma. Moreover, only a relatively small sample plasma volume (100 microliter) is required, allowing this method to be applied to samples taken from neonates.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
An integrative GC-MS and LC-MS metabolomics platform determination of the metabolite profile of Bombax ceiba L. root, and in silico & in vitro evaluation of its antibacterial & antidiabetic activities

Alrabie A, Alrabie NA, AlSaeedy M, Al-Adhreai A, Al-Qadsy I, Al-Horaibi SA, et al.

Nat Prod Res, 2023 Jul;37(13):2263-2268.
PMID: 36441059 DOI: 10.1080/14786419.2022.2149519

The Bombax ceiba L. tree is a member of the family Bombacaceae and the genus Bombax. Both Chinese and Indian traditional medicine have made extensive use of it in the treatment of sickness. Its chemical composition is still a mystery. B. ceiba roots methanol extract (BCRME) was analyzed by different chromatographic analytical techniques in order to identify its major chemical constituents. Twelve compounds and six compounds were identified from GC-MS and LC-MS analysis, respectively. This is the first report on the presence of lathodoratin, cedrene, 4H-1-benzopyran-4-one,8-[{dimethylamino} methyl]-7-methoxy-3-methyl-2-phenyl, asiatic acid, and (E)-2,4,4'-trihydroxylchalcone in B. ceiba roots. Methanol extract demonstrated noteworthy antibacterial activity against Staphylococcus aureus (MTCC96) (MIC: 100 µg/mL) compare to antibiotic ampicillin (MIC: 250 µg/mL) as well as the highest α-amylase inhibition (IC50=26.91 µg/mL) and α-glucosidase inhibition (IC50=21.21 µg/mL) effects, molecular docking study confirmed these findings, with some compounds having a very high docking score.

Matched MeSH terms: Chromatography, Liquid; Gas Chromatography-Mass Spectrometry
Fulltext Chromatographic Separation of Vitamin E Enantiomers

Fu JY, Htar TT, De Silva L, Tan DM, Chuah LH

Molecules, 2017 Feb 04;22(2).
PMID: 28165404 DOI: 10.3390/molecules22020233

Vitamin E is recognized as an essential vitamin since its discovery in 1922. Most vegetable oils contain a mixture of tocopherols and tocotrienols in the vitamin E composition. Structurally, tocopherols and tocotrienols share a similar chromanol ring and a side chain at the C-2 position. Owing to the three chiral centers in tocopherols, they can appear as eight different stereoisomers. Plant sources of tocopherol are naturally occurring in the form of RRR while synthetic tocopherols are usually in the form of all-racemic mixture. Similarly, with only one chiral center, natural tocotrienols occur as the R-isoform. In this review, we aim to discuss a few chromatographic methods that had been used to separate the stereoisomers of tocopherols and tocotrienols. These methods include high performance liquid chromatography, gas chromatography and combination of both. The review will focus on method development including selection of chiral columns, detection method and choice of elution solvent in the context of separation efficiency, resolution and chiral purity. The applications for separation of enantiomers in vitamin E will also be discussed especially in terms of the distinctive biological potency among the stereoisoforms.

Matched MeSH terms: Chromatography, Gas; Chromatography, High Pressure Liquid
Characterization and determination of casein glycomacropeptide in dairy products by UHPLC-MS/MS based on its characteristic peptide

Chen Q, Lai S, Dong L, Liu Y, Pan D, Wu Z, et al.

Food Chem, 2024 Jan 01;430:137049.
PMID: 37544157 DOI: 10.1016/j.foodchem.2023.137049

The ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS) method was built to quantify the casein glycomacropeptide (CGMP) in bovine dairy products accurately based on targeted proteomics. Qualitative analysis of theoretical peptides was carried out using high-resolution mass spectrometry (HRMS) and protein software. Isotope-labeled characteristic peptides were acquired via the labeled amino acid condensation method to correct the matrix effects. Peptide MAIPPK was the representative characteristic peptide for distinguishing the CGMP from κ-casein through trypsin digestion. After optimizing the pre-treatment conditions, the final 8% oxidant concentration was selected and the 10% formic acid concentration with 2.5 h oxidation time. Moreover, the results of methodological verification showed that the recovery rate was 103.7%, meanwhile the precision of inter-day and intra-day was less than 5%. In conclusion, the research demonstrated the characteristic peptide MAIPPK could quantitatively applied to detect CGMP in dairy products.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods
A simple and high efficiency purification of His-tagged turnip yellow mosaic virus-like particle (TYMV-VLP) by nickel ion affinity precipitation

Tan FH, Ng JF, Mohamed Alitheen NB, Muhamad A, Yong CY, Lee KW

J Virol Methods, 2023 Sep;319:114771.
PMID: 37437780 DOI: 10.1016/j.jviromet.2023.114771

Virus-like particles (VLPs) is one of the most favourable subjects of study, especially in the field of nanobiotechnology and vaccine development because they possess good immunogenicity and self-adjuvant properties. Conventionally, VLPs can be tagged and purified using affinity chromatography or density gradient ultracentrifugation which is costly and time-consuming. Turnip yellow mosaic virus (TYMV) is a plant virus, where expression of the viral coat protein (TYMVc) in Escherichia coli (E. coli) has been shown to form VLP. In this study, we report a non-chromatographic method for VLP purification using C-terminally His-tagged TYMVc (TYMVcHis6) as a protein model. Firstly, the TYMVcHis6 was cloned and expressed in E. coli. Upon clarification of cell lysate, nickel (II) chloride [NiCl2; 15 µM or equivalent to 0.0000194% (w/v)] was added to precipitate TYMVcHis6. Following centrifugation, the pellet was resuspended in buffer containing 1 mM EDTA to chelate Ni2+, which is then removed via dialysis. A total of 50% of TYMVcHis6 was successfully recovered with purity above 0.90. Later, the purified TYMVcHis6 was analysed with sucrose density ultracentrifugation, dynamic light scattering (DLS), and transmission electron microscopy (TEM) to confirm VLP formation, which is comparable to TYMVcHis6 purified using the standard immobilized metal affinity chromatography (IMAC) column. As the current method omitted the need for IMAC column and beads while significantly reducing the time needed for column washing, nickel affinity precipitation represents a novel method for the purification of VLPs displaying poly-histidine tags (His-tags).

Matched MeSH terms: Chromatography, Affinity/methods
Characteristic fingerprint based on gingerol derivative analysis for discrimination of ginger (Zingiber officinale) according to geographical origin using HPLC-DAD combined with chemometrics

Yudthavorasit S, Wongravee K, Leepipatpiboon N

Food Chem, 2014 Sep 01;158:101-11.
PMID: 24731320 DOI: 10.1016/j.foodchem.2014.02.086

Chromatographic fingerprints of gingers from five different ginger-producing countries (China, India, Malaysia, Thailand and Vietnam) were newly established to discriminate the origin of ginger. The pungent bioactive principles of ginger, gingerols and six other gingerol-related compounds were determined and identified. Their variations in HPLC profiles create the characteristic pattern of each origin by employing similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and linear discriminant analysis (LDA). As results, the ginger profiles tended to be grouped and separated on the basis of the geographical closeness of the countries of origin. An effective mathematical model with high predictive ability was obtained and chemical markers for each origin were also identified as the characteristic active compounds to differentiate the ginger origin. The proposed method is useful for quality control of ginger in case of origin labelling and to assess food authenticity issues.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
Exploring stingless bee honey from selected regions of Peninsular Malaysia through gas chromatography-mass spectrometry-based untargeted metabolomics

Manickavasagam G, Saaid M, Lim V

J Food Sci, 2024 Feb;89(2):1058-1072.
PMID: 38221804 DOI: 10.1111/1750-3841.16903

Volatile organic compounds in honey are known for their considerable impact on the organoleptic properties of honey, such as aroma, flavor, taste, and texture. The type and composition of volatile organic compounds are influenced by entomological, geographical, and botanical origins; thus, these compounds have the potential to be chemical markers. Sixty-two volatile compounds were identified using gas chromatography-mass spectrometry from 30 Heterotrigona itama (H. itama) honey samples from 3 different geographical origins. Hydrocarbons and benzene derivatives were the dominant classes of volatile organic compounds in the samples. Both clustering and discriminant analyses demonstrated a clear separation between samples from distant origins (Kedah and Perak), and the volcano plot supported it. The reliability and predictability of the partial least squares-discriminant analysis model from the discriminant analysis were validated using cross-validation (R2 : 0.93; Q2 : 0.83; accuracy: 0.97) and the permutation test (p 1.0) and the Kruskal-Wallis test (p

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods
Fulltext DNA, RNA, and protein extraction: the past and the present

Tan SC, Yiap BC

J Biomed Biotechnol, 2009;2009:574398.
PMID: 20011662 DOI: 10.1155/2009/574398

Extraction of DNA, RNA, and protein is the basic method used in molecular biology. These biomolecules can be isolated from any biological material for subsequent downstream processes, analytical, or preparative purposes. In the past, the process of extraction and purification of nucleic acids used to be complicated, time-consuming, labor-intensive, and limited in terms of overall throughput. Currently, there are many specialized methods that can be used to extract pure biomolecules, such as solution-based and column-based protocols. Manual method has certainly come a long way over time with various commercial offerings which included complete kits containing most of the components needed to isolate nucleic acid, but most of them require repeated centrifugation steps, followed by removal of supernatants depending on the type of specimen and additional mechanical treatment. Automated systems designed for medium-to-large laboratories have grown in demand over recent years. It is an alternative to labor-intensive manual methods. The technology should allow a high throughput of samples; the yield, purity, reproducibility, and scalability of the biomolecules as well as the speed, accuracy, and reliability of the assay should be maximal, while minimizing the risk of cross-contamination.

Matched MeSH terms: Chromatography/methods*
Rapid detection of Ganoderma-infected oil palms by microwave ergosterol extraction with HPLC and TLC

Muniroh MS, Sariah M, Zainal Abidin MA, Lima N, Paterson RR

J Microbiol Methods, 2014 May;100:143-7.
PMID: 24681306 DOI: 10.1016/j.mimet.2014.03.005

Detection of basal stem rot (BSR) by Ganoderma of oil palms was based on foliar symptoms and production of basidiomata. Enzyme-Linked Immunosorbent Assays-Polyclonal Antibody (ELISA-PAB) and PCR have been proposed as early detection methods for the disease. These techniques are complex, time consuming and have accuracy limitations. An ergosterol method was developed which correlated well with the degree of infection in oil palms, including samples growing in plantations. However, the method was capable of being optimised. This current study was designed to develop a simpler, more rapid and efficient ergosterol method with utility in the field that involved the use of microwave extraction. The optimised procedure involved extracting a small amount of Ganoderma, or Ganoderma-infected oil palm suspended in low volumes of solvent followed by irradiation in a conventional microwave oven at 70°C and medium high power for 30s, resulting in simultaneous extraction and saponification. Ergosterol was detected by thin layer chromatography (TLC) and quantified using high performance liquid chromatography with diode array detection. The TLC method was novel and provided a simple, inexpensive method with utility in the field. The new method was particularly effective at extracting high yields of ergosterol from infected oil palm and enables rapid analysis of field samples on site, allowing infected oil palms to be treated or culled very rapidly. Some limitations of the method are discussed herein. The procedures lend themselves to controlling the disease more effectively and allowing more effective use of land currently employed to grow oil palms, thereby reducing pressure to develop new plantations.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods*; Chromatography, Thin Layer/methods*
Analysis of differentially expressed proteins in colorectal cancer using hydroxyapatite column and SDS-PAGE

Lim SR, Gooi BH, Singh M, Gam LH

Appl Biochem Biotechnol, 2011 Nov;165(5-6):1211-24.
PMID: 21863284 DOI: 10.1007/s12010-011-9339-3

Limitation on two dimensional (2D) gel electrophoresis technique causes some proteins to be under presented, especially the extreme acidic, basic, or membrane proteins. To overcome the limitation of 2D electrophoresis, an analysis method was developed for identification of differentially expressed proteins in normal and cancerous colonic tissues using self-pack hydroxyapatite (HA) column. Normal and cancerous colon tissues were homogenized and proteins were extracted using sodium phosphate buffer at pH 6.8. Protein concentration was determined and the proteins were loaded unto the HA column. HA column reduced the complexity of proteins mixture by fractionating the proteins according to their ionic strength. Further protein separation was accomplished by a simple and cost effective sodium dodecyl sulfate-polyacrylamide gel electrophoresis method. The protein bands were subjected to in-gel digestion and protein analysis was performed using electrospray ionization (ESI) ion trap mass spectrometer. There were 17 upregulated proteins and seven downregulated proteins detected with significant differential expression. Some of these proteins were low abundant proteins or proteins with extreme pH that were usually under presented in 2D gel analysis. We have identified brain mitochondrial carrier protein 1, T-cell surface glycoprotein CD1a, SOSS complex subunit B2, and Protein Jade 1 which were previously not detected in 2D gel analysis method.

Matched MeSH terms: Chromatography/economics; Chromatography/instrumentation; Chromatography/methods*

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