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  1. Saad LB, Hwi KK, Quah T
    PMID: 25371587
    BACKGROUND: There are severe adverse effects of analgesic drugs on human body. Extraction of analgesic drugs from natural products has therefore become the prime objective of the study. In this study, we aimed to evaluate the antinociceptive activity of the pomegranate fruit.

    MATERIALS AND METHODS: Antinociceptive activity of ethanol pomegranate extract was examined using three models of pain: the writhing test, the hot tail flick test and the plantar test. The ethanolic extract of pomegranate was administered by oral gavages in doses of (100,150 and 200mg/kg, p.o (orally)), for all the tests and compared with aspirin (100mg/kg, p.o.) which was considered as the standard drug. Phytochemical screening and HPLC analysis of the plant species was carried out.

    RESULTS: In the writhing test, the index of pain inhibition (IPI) was 37% for ethanolic extract of pomegranate (200mg/kg, p.o.), and 59% for aspirin. In the hot tail flick test, the ethanolic extract of pomegranate (200mg/kg, p.o.), has shown significant analgesia reaching its peak at 60 min maximum possible analgesia (MPA), was 24.1% as compared with aspirin 37.5%. Hyperalgesia was successfully induced by the plantar test and the ethanol extract of pomegranate (100,150,200mg/kg, p.o.), reduced the hyperalgesia in a dose dependent manner comparable to aspirin at (100mg/kg, p.o.). HPLC analysis revealed the presence of gallic acid, ellagic acid and Punicalagins A&B.

    CONCLUSION: The results demonstrated that ethanol pomegranate extract has an antinociceptive effect that may be related to the presence of identified phytochemicals.

    Matched MeSH terms: Chromatography, High Pressure Liquid
  2. Agatonovic-Kustrin S, Babazadeh Ortakand D, Morton DW, Yusof AP
    J Chromatogr A, 2015 Mar 13;1385:103-10.
    PMID: 25666499 DOI: 10.1016/j.chroma.2015.01.067
    The present study describes a simple high performance thin layer chromatographic (HPTLC) method for the simultaneous quantification of apigenin, chamazulene, bisabolol and the use of DPPH free radical as a post-chromatographic derivatization agent to compare the free radical scavenging activities of these components in leaf and flower head extracts from feverfew, German chamomile and marigold from the Asteraceae family. Feverfew (Tanacetum parthenium) leaves have been traditionally used in the treatment of migraine with parthenolide being the main bioactive compound. However, due to similar flowers, feverfew is sometimes mistaken for the German chamomile (Matricaria recutita). Bisabolol and chamazulene are the main components in chamomile essential oil. Marigold (Calendula officinalis) was included in the study for comparison, as it belongs to the same family. Parthenolide was found to be present in all leaf extracts but was not detected in calendula flower extract. Chamazulene and bisabolol were found to be present in higher concentrations in chamomile and Calendula flowers. Apigenin was detected and quantified only in chamomile extracts (highest concentration in flower head extracts). Antioxidant activity in sample extracts was compared by superimposing the chromatograms obtained after post-chromatographic derivatization with DPPH and post-chromatographic derivatization with anisaldehyde. It was found that extracts from chamomile flower heads and leaves have the most prominent antioxidant activity, with bisabolol and chamazulene being the most effective antioxidants.
    Matched MeSH terms: Chromatography, Thin Layer
  3. 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: Gas Chromatography-Mass Spectrometry
  4. Abdul Keyon AS, Guijt RM, Bolch CJ, Breadmore MC
    J Chromatogr A, 2014 Oct 17;1364:295-302.
    PMID: 25223612 DOI: 10.1016/j.chroma.2014.08.074
    The accumulation of paralytic shellfish toxins (PSTs) in contaminated shellfish is a serious health risk making early detection important to improve shellfish safety and biotoxin management. Capillary electrophoresis (CE) has been proven as a high resolution separation technique compatible with miniaturization, making it an attractive choice in the development of portable instrumentation for early, on-site detection of PSTs. In this work, capillary zone electrophoresis (CZE) with capacitively coupled contactless conductivity detector (C(4)D) and UV detection were examined with counter-flow transient isotachophoresis (tITP) to improve the sensitivity and deal with the high conductivity sample matrix. The high sodium concentration in the sample was used as the leading ion while l-alanine was used as the terminating electrolyte (TE) and background electrolyte (BGE) in which the toxins were separated. Careful optimization of the injected sample volume and duration of the counter-flow resulted in limit of detections (LODs) ranging from 74.2 to 1020 ng/mL for tITP-CZE-C(4)D and 141 to 461 ng/mL for tITP-CZE-UV, an 8-97 fold reduction compared to conventional CZE. The LODs were adequate for the analysis of PSTs in shellfish samples close to the regulatory limit. Intra-day and inter-day repeatability values (percentage relative standard deviation, n=3) of tITP-CZE-C(4)D and tITP-CZE-UV methods for both migration time and peak height were in the range of 0.82-11% and 0.76-10%, respectively. The developed method was applied to the analysis of a contaminated mussel sample and validated against an Association of Official Analytical Chemists (AOAC)-approved method for PSTs analysis by high performance liquid chromatography (HPLC) with fluorescence detection (FLD) after pre-column oxidation of the sample. The method presented has potential for incorporation in to field-deployable devices for the early detection of PSTs on-site.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  5. Moniruzzaman M, Yung An C, Rao PV, Hawlader MN, Azlan SA, Sulaiman SA, et al.
    Biomed Res Int, 2014;2014:737490.
    PMID: 25045696 DOI: 10.1155/2014/737490
    The aim of the present study was to characterize the phenolic acids, flavonoids, and antioxidant properties of monofloral honey collected from five different districts in Bangladesh. A new high performance liquid chromatography (HPLC) equipped with a UV detector method was developed for the identification of the phenolic acids and flavonoids. A total of five different phenolic acids were identified, with the most abundant being caffeic acid, benzoic acid, gallic acid, followed by chlorogenic acid and trans-cinnamic acid. The flavonoids, kaempferol, and catechin were most abundant, followed by myricetin and naringenin. The mean moisture content, total sugar content, and color characteristics of the honey samples were 18.36 ± 0.95%, 67.40 ± 5.63 g/100 g, and 129.27 ± 34.66 mm Pfund, respectively. The mean total phenolic acids, total flavonoid content, and proline content were 199.20 ± 135.23, 46.73 ± 34.16, and 556.40 ± 376.86 mg/kg, respectively, while the mean FRAP values and DPPH radical scavenging activity were 327.30 ± 231.87 μM Fe (II)/100 g and 36.95 ± 20.53%, respectively. Among the different types of honey, kalijira exhibited the highest phenolics and antioxidant properties. Overall, our study confirms that all the investigated honey samples are good sources of phenolic acids and flavonoids with good antioxidant properties.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  6. Mumtaz MW, Mukhtar H, Anwar F, Saari N
    ScientificWorldJournal, 2014;2014:526105.
    PMID: 25162053 DOI: 10.1155/2014/526105
    Current study presents RSM based optimized production of biodiesel from palm oil using chemical and enzymatic transesterification. The emission behavior of biodiesel and its blends, namely, POB-5, POB-20, POB-40, POB-50, POB-80, and POB-100 was examined using diesel engine (equipped with tube well). Optimized palm oil fatty acid methyl esters (POFAMEs) yields were depicted to be 47.6 ± 1.5, 92.7 ± 2.5, and 95.4 ± 2.0% for chemical transesterification catalyzed by NaOH, KOH, and NaOCH3, respectively, whereas for enzymatic transesterification reactions catalyzed by NOVOZYME-435 and A. n. lipase optimized biodiesel yields were 94.2 ± 3.1 and 62.8 ± 2.4%, respectively. Distinct decrease in particulate matter (PM) and carbon monoxide (CO) levels was experienced in exhaust emissions from engine operating on biodiesel blends POB-5, POB-20, POB-40, POB-50, POB-80, and POB-100 comparative to conventional petroleum diesel. Percentage change in CO and PM emissions for different biodiesel blends ranged from -2.1 to -68.7% and -6.2 to -58.4%, respectively, relative to conventional diesel, whereas an irregular trend was observed for NOx emissions. Only POB-5 and POB-20 showed notable reductions, whereas all other blends (POB-40 to POB-100) showed slight increase in NOx emission levels from 2.6 to 5.5% comparative to petroleum diesel.
    Matched MeSH terms: Chromatography, Gas
  7. Thangalazhy-Gopakumar S, Al-Nadheri WM, Jegarajan D, Sahu JN, Mubarak NM, Nizamuddin S
    Bioresour Technol, 2015 Feb;178:65-9.
    PMID: 25278112 DOI: 10.1016/j.biortech.2014.09.068
    In this study, pyrolysis technique was utilized for converting palm oil sludge to value added materials: bio-oil (liquid fuel) and bio-char (soil amendment). The bio-oil yield obtained was 27.4±1.7 wt.% having a heating value of 22.2±3.7 MJ/kg and a negligible ash content of 0.23±0.01 wt.%. The pH of bio-oil was in alkaline region. The bio-char yielded 49.9±0.3 wt.%, which was further investigated for sorption efficiency by adsorbing metal (Cd(2+) ions) from water. The removal efficiency of Cd(2+) was 89.4±2%, which was almost similar to the removal efficiency of a commercial activated carbon. The adsorption isotherm was well described by Langmuir model. Therefore, pyrolysis is proved as an efficient tool for palm oil sludge management, where the waste was converted into valuable products.
    Matched MeSH terms: Gas Chromatography-Mass Spectrometry
  8. Mohd Amin MF, Heijman SG, Lopes SI, Rietveld LC
    ScientificWorldJournal, 2014;2014:162157.
    PMID: 25197693 DOI: 10.1155/2014/162157
    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism.
    Matched MeSH terms: Chromatography, Gas
  9. Ben-Hander GM, Makahleh A, Saad B, Saleh MI, Cheng KW
    Talanta, 2015 Jan;131:590-6.
    PMID: 25281145 DOI: 10.1016/j.talanta.2014.08.037
    A new analytical method for the simultaneous determination of the antidiabetic drugs rosiglitazone (ROS) and metformin hydrochloride (MH) with marked differences in their affinity towards organic solvents (log P of 2.4 and -1.43, respectively) was developed. Prior to the HPLC separation, the drugs were subjected to a sequential hollow fiber liquid phase microextraction (HF-LPME) procedure. Two sequential HF-LPME approaches were considered, the preferred one involves the use of two vials containing solution mixtures for the extraction of ROS (vial 1) and MH (vial 2), respectively, but using the same fiber and acceptor phase. Important parameters that affect the extraction efficiency such as extracting solvent, donor phase conditions, HCl concentration, agitation, extraction time, addition of salt, etc. were studied. Under the optimum conditions, good enrichment factors (EF, 471 and 86.6 for ROS and MH, respectively) were achieved. Calibration curves were linear over the range 1-500 (r(2)=0.998) and 5-2500 ng mL(-1) (r(2)=0.999) for ROS and MH, respectively. The relative standard deviation values (RSD%) for six replicates were below 8.4%. Detection and quantitation limits based on S/N ratio of 3 and 10 were 0.12, 1.0 and 0.36, 3.0 ng mL(-1) for ROS and MH, respectively. The proposed method is simple, sensitive and opens up new opportunities for the microextraction of analytes with contrasting properties.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  10. Raoov M, Mohamad S, bin Abas MR, Surikumaran H
    Talanta, 2014 Dec;130:155-63.
    PMID: 25159393 DOI: 10.1016/j.talanta.2014.06.067
    Cyclodextrin-ionic liquid polymer (βCD-BIMOTs-TDI) is a new class of macroporous material and has great potential to be used as an SPE adsorbent material for extraction of phenols in river water samples. Six phenols, as model analytes, were extracted on a βCD-BIMOTs-TDI SPE cartridge, and then, eluted with 2 mL of methanol containing 1% acetic acid. The optimum experimental condition was 15 mL of sample volume (sample at pH 6) and 2 mL of methanol containing 1% acetic acid as an eluent solvent. The eluent concentration was determined by using Gas Chromatography-Flame Ionization Detector (GC-FID). Under optimized condition, high sensitivity (detection limits 0.23-0.35 µg/L) and good recoveries (87-116%) were achieved with satisfactory relative standard deviation (RSD) (0.1-1.7%). The developed βCD-BIMOTs-TDI-SPE was then compared with other adsorbents, and the obtained results showed that the βCD-BIMOTs-TDI exhibited higher extraction recovery due to the unique structure and properties. Finally, the βCD-BIMOTs-TDI was applied as a solid phase extraction sorbent for phenols determination under optimized condition, in river and tap waters, prior to the GC-FID separation.
    Matched MeSH terms: Chromatography, Gas
  11. Teo CL, Idris A
    Bioresour Technol, 2014 Nov;171:477-81.
    PMID: 25201293 DOI: 10.1016/j.biortech.2014.08.024
    The types of microalgae strains and the method used in lipid extraction have become crucial factors which influence the productivity of crude oil. In this paper, Nannochloropsis sp. and Tetraselmis sp. were chosen as the strains and four different methods were used to extract the lipids: Hara and Radin, Folch, Chen and Bligh and Dyer. These methods were performed by using conventional heating and microwave irradiation methods. Results revealed that highest lipid yield from the different species was obtained using different extraction methods; both under microwave irradiation. The lipid yield for Tetraselmis sp. and Nannochloropsis sp. was highest when Hara and Radin (8.19%), and Folch (8.47%) methods were used respectively under microwave irradiation. The lipids extracted were then transesterified to biodiesel and the quality of the biodiesel was analyzed using the gas chromatography.
    Matched MeSH terms: Chromatography, Gas
  12. Shukor H, Al-Shorgani NK, Abdeshahian P, Hamid AA, Anuar N, Rahman NA, et al.
    Bioresour Technol, 2014 Oct;170:565-73.
    PMID: 25171212 DOI: 10.1016/j.biortech.2014.07.055
    Palm kernel cake (PKC) was used for biobutanol production by Clostridium saccharoperbutylacetonicum N1-4 in acetone-butanol-ethanol (ABE) fermentation. PKC was subjected to acid hydrolysis pretreatment and hydrolysates released were detoxified by XAD-4 resin. The effect of pH, temperature and inoculum size on butanol production was evaluated using an empirical model. Twenty ABE fermentations were run according to an experimental design. Experimental results revealed that XAD-4 resin removed 50% furfural and 77.42% hydroxymethyl furfural. The analysis of the empirical model showed that linear effect of inoculums size with quadratic effect of pH and inoculum size influenced butanol production at 99% probability level (P<0.01). The optimum conditions for butanol production were pH 6.28, temperature of 28°C and inoculum size of 15.9%. ABE fermentation was carried out under optimum conditions which 0.1g/L butanol was obtained. Butanol production was enhanced by diluting PKC hydrolysate up to 70% in which 3.59g/L butanol was produced.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  13. Maail CM, Ariffin H, Hassan MA, Shah UK, Shirai Y
    Biomed Res Int, 2014;2014:465270.
    PMID: 25057489 DOI: 10.1155/2014/465270
    Oil palm frond (OPF) juice is a potential industrial fermentation substrate as it has high sugars content and the OPF are readily available daily. However, maximum sugars yield and storage stability of the OPF juice are yet to be determined. This study was conducted to determine the effect of physical pretreatment and storage duration of OPF petiole on sugars yield. Storage stability of OPF juice at different storing conditions was also investigated. It was found that OPF petiole squeezed by hydraulic pressing machine gave the highest sugars recovery at almost 40 g/kg, accounting for a recovery yield of 88%. Storage of OPF petiole up to 72 hrs prior to squeezing reduced the free sugars by 11 g/kg. Concentrated OPF juice with 95% water removal had the best storage stability at both 4 and 30°C, when it was stored for 10 days. Moreover, concentrated OPF syrup prepared by thermal processing did not give any Maillard effect on microbial growth. Based on our results, OPF juice meets all the criteria as a good fermentation substrate as it is renewable, consistently available, and easy to be obtained, it does not inhibit microbial growth and product formation, and it contains no impurities.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  14. Keyon AS, Guijt RM, Gaspar A, Kazarian AA, Nesterenko PN, Bolch CJ, et al.
    Electrophoresis, 2014 May;35(10):1496-503.
    PMID: 24591173 DOI: 10.1002/elps.201300353
    Paralytic shellfish toxins (PSTs) are produced by marine and freshwater microalgae and accumulate in shellfish including mussels, oysters, and scallops, causing possible fatalities when inadvertently consumed. Monitoring of PST content of shellfish is therefore important for food safety, with currently approved methods based on HPLC, using pre- or postcolumn oxidation for fluorescence detection (HPLC-FLD). CE is an attractive alternative for screening and detection of PSTs as it is compatible with miniaturization and could be implemented in portable instrumentation for on-site monitoring. In this study, CE methods were developed for C(4) D, FLD, UV absorption detection, and MS-making this first report of C(4) D and FLD for PSTs detection. Because most oxidized toxins are neutral, MEKC was used in combination with FLD. The developed CZE-UV and CZE-C(4) D methods provide better resolution, selectivity, and separation efficiency compared to CZE-MS and MEKC-FLD. The sensitivity of the CZE-C(4) D and MEKC-FLD methods was superior to UV and MS, with LOD values ranging from 140 to 715 ng/mL for CZE-C(4) D and 60.9 to 104 ng/mL for MEKC-FLD. With the regulatory limit for shellfish samples of 800 ng/mL, the CZE-C(4) D and MEKC-FLD methods were evaluated for the screening and detection of PSTs in shellfish samples. While the CZE-C(4) D method suffered from significant interferences from the shellfish matrix, MEKC-FLD was successfully used for PST screening of a periodate-oxidized mussel sample, with results confirmed by HPLC-FLD. This confirms the potential of MEKC-FLD for screening of PSTs in shellfish samples.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  15. Ghani NA, Sulaiman J, Ismail Z, Chan XY, Yin WF, Chan KG
    Sensors (Basel), 2014;14(4):6463-73.
    PMID: 24721765 DOI: 10.3390/s140406463
    Two microbial isolates from a Malaysian shoreline were found to be capable of degrading N-acylhomoserine lactones. Both Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry and 18S rDNA phylogenetic analyses confirmed that these isolates are Rhodotorula mucilaginosa. Quorum quenching activities were detected by a series of bioassays and rapid resolution liquid chromatography analysis. The isolates were able to degrade various quorum sensing molecules namely N-hexanoyl-L-homoserine lactone (C6-HSL), N-(3-oxo-hexanoyl)-L-homoserine lactone (3-oxo-C6-HSL) and N-(3-hydroxyhexanoyl)-L-homoserine lactone (3-hydroxy-C6-HSL). Using a relactonisation assay to verify the quorum quenching mechanism, it is confirmed that Rh. mucilaginosa degrades the quorum sensing molecules via lactonase activity. To the best of our knowledge, this is the first documentation of the fact that Rh. mucilaginosa has activity against a broad range of AHLs namely C6-HSL, 3-oxo-C6-HSL and 3-hydroxy-C6-HSL.
    Matched MeSH terms: Chromatography, Liquid
  16. Ee R, Lim YL, Kin LX, Yin WF, Chan KG
    Sensors (Basel), 2014;14(6):10177-86.
    PMID: 24919016 DOI: 10.3390/s140610177
    Strain RB38 was recovered from a former dumping area in Malaysia. MALDI-TOF mass spectrometry and genomic analysis identified strain RB-38 as Pandoraea pnomenusa. Various biosensors confirmed its quorum sensing properties. High resolution triple quadrupole liquid chromatography-mass spectrometry analysis was subsequently used to characterize the N-acyl homoserine lactone production profile of P. pnomenusa strain RB38, which validated that this isolate produced N-octanoyl homoserine lactone as a quorum sensing molecule. This is the first report of the production of N-octanoyl homoserine lactone by P. pnomenusa strain RB38.
    Matched MeSH terms: Chromatography, Liquid
  17. Lau CC, Abdullah N, Shuib AS, Aminudin N
    Food Chem, 2014 Apr 1;148:396-401.
    PMID: 24262574 DOI: 10.1016/j.foodchem.2013.10.053
    Angiotensin I-converting enzyme (ACE) inhibitors derived from foods are valuable auxiliaries to agents such as captopril. Eight highly functional ACE inhibitory peptides from the mushroom, Agaricus bisporus, were identified by LC-MS/MS. Among these peptides, the most potent ACE inhibitory activity was exhibited by AHEPVK, RIGLF and PSSNK with IC₅₀ values of 63, 116 and 129 μM, respectively. These peptides exhibited high ACE inhibitory activity after gastrointestinal digestion. Lineweaver-Burk plots suggested that AHEPVK and RIGLF act as competitive inhibitors against ACE, whereas PSSNK acts as a non-competitive inhibitor. Mushrooms can be a good component of dietary supplement due to their readily available source and, in addition, they rarely cause food allergy. Compared to ACE inhibitory peptides isolated from other edible mushrooms, AHEPVK, RIGLF and PSSNK have lower IC₅₀ values. Therefore, these peptides may serve as an ideal ingredient in the production of antihypertensive supplements.
    Matched MeSH terms: Chromatography, Liquid
  18. Lee-Yin C, Ismaill BS, Salmijah S, Halimah M
    J Environ Biol, 2013 Sep;34(5):957-61.
    PMID: 24558812
    The influence of temperature, moisture and organic matter on the persistence of cyfluthrin was determined using three types of Malaysian soils, namely clay, clay loam and sandy clay loam obtained from a tomato farm in Cameron Highlands, Pahang. The persistence of cyfluthrin was observed in the laboratory at two temperature levels of 25 and 35 degreeC and field water capacity of 30 and 80%. Treated soil samples were incubated in a growth chamber for 1, 2, 3, 5, 7, 10, 14, 21 and 28 days. The results from the incubation studies showed that temperature and organic matter content significantly reduced the half-life (t1/2) values of cyfluthrin in the three soil types, but moisture content had very little effect. It was observed that cyfluthrin persisted longer at lower temperature and moisture content and higher organic matter content in all the three soil types. The present study demonstrated that under the tropical conditions of Malaysia, cyfluthrin dissipated rapidly in soils compared to its dissipation in soils of temperate regions, evidently due to high temperature.
    Matched MeSH terms: Chromatography, Gas
  19. Chua LS, Yap KC, Jaganath IB
    Nat Prod Commun, 2013 Dec;8(12):1725-9.
    PMID: 24555283
    The total phenolic content and radical scavenging activity of Andrographis paniculata has been investigated to estimate the amount of phenolic compounds and diterpene lactones, respectively in the plant extracts. The stem extracts exhibited higher total phenolic content and scavenging activity than those of the leaf extracts from both young and mature plants. A range of 19.6-47.8 mg extract of A. paniculata from different parts of the plant is equivalent to the scavenging activity exhibited by one mg of standard Trolox. HPLC-ESI-MS/MS was also used to identify simultaneously the phytochemicals from the leaves and stems of both young and mature plant samples. Of the identified compounds, seven of the sixteen diterpene lactones, three of the six flavonoids, five of the six phenolic acids and two cyclic acids are reported here for the first time for this species. Multivariate statistical approaches such as Hierarchiral Component Analysis (HCA) and Principle Component Analysis (PCA) have clustered the plant extracts into the leaf and stem groups, regardless of plant age. Further classification based on the phytochemical profiles revealed that mostly phenolic acids and flavonoids were from the young leaf extracts, and diterpenoids and their glycosides from the mature leaf extracts. However, the phytochemical profiles for the stems of both young and mature plants were not significantly different as presented in the dendrogram of HCA and the score plot of PCA. The marker for mature plants might be the m/z 557 ion (dihydroxyl dimethyl 19-[(beta-D-glucopyranosyl)oxy]-19-oxo-ent-labda-8(17),13-dien-16,15-olide), whereas the m/z 521 ion (propyl neoandrographolide) could be the marker for leaf extracts.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  20. Ahmad-Tajudin A, Adler B, Ekström S, Marko-Varga G, Malm J, Lilja H, et al.
    Anal Chim Acta, 2014 Jan 7;807:1-8.
    PMID: 24356215 DOI: 10.1016/j.aca.2013.08.051
    To address immunocapture of proteins in large cohorts of clinical samples high throughput sample processing is required. Here a method using the proteomic sample platform, ISET (integrated selective enrichment target) that integrates highly specific immunoaffinity capture of protein biomarker, digestion and sample cleanup with a direct interface to mass spectrometry is presented. The robustness of the on-ISET protein digestion protocol was validated by MALDI MS analysis of model proteins, ranging from 40 fmol to 1 pmol per nanovial. On-ISET digestion and MALDI MS/MS analysis of immunoaffinity captured disease-associated biomarker PSA (prostate specific antigen) from human seminal plasma are presented.
    Matched MeSH terms: Chromatography, Affinity
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