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Dive into the research topics where James R. Hennell is active.

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Featured researches published by James R. Hennell.


Journal of Pharmaceutical and Biomedical Analysis | 2007

Validation of a method for the simultaneous determination of four schisandra lignans in the raw herb and commercial dried aqueous extracts of Schisandra chinensis (Wu Wei Zi) by RP-LC with DAD.

C.W. Halstead; Samiuela Lee; Cheang S. Khoo; James R. Hennell; Alan Bensoussan

A rapid and specific reversed-phase high performance liquid chromatography (RP-LC) method with photodiode array detection (DAD) was developed and validated for the determination of four common schisandra lignans, schisandrin (1), schisandrol B (2), deoxyshisandrin (3) and gamma-schisandrin (4), in raw herb materials and commercial dried aqueous extracts of Schisandra chinensis (Wu Wei Zi). The extraction solvent and extraction method were optimised where it was found that a 4 h Soxhlet extraction using methanol was successful at extracting >99.5% of each of the schisandra lignans analysed from the raw herb material. The sample preparation process for the dried aqueous extract samples involved sonication using methanol for 2 x 30 min. The herb and extract solutions were separated on a Varian Microsorb-MV 100-5 C18 column using a gradient mixture of 0.1% aqueous phosphoric acid and acetonitrile. Subsequent detection and quantitation of the schisandra lignans was performed at 210 nm. The correlation coefficients of the linear regression analysis performed on these calibration curves were >0.9996 for all four schisandra lignans assayed. The detection limits and quantification limits ranged from 0.12 to 0.57 and 0.41 to 1.89 mg g(-1), respectively. The mean recoveries of the various analytes ranged from 92.20 to 107.01%. The method was used to investigate the levels of the four mentioned components in herb samples and dried aqueous extracts. The identities of the chromatographic peaks were confirmed by (+) electrospray ionisation LC-MS/MS.


Journal of Pharmaceutical and Biomedical Analysis | 2008

The determination of glycyrrhizic acid in Glycyrrhiza uralensis Fisch. ex DC. (Zhi Gan Cao) root and the dried aqueous extract by LC–DAD

James R. Hennell; Samiuela Lee; Cheang Khoo; Michael J. Gray; Alan Bensoussan

A rapid, sensitive and specific reversed phase high-performance liquid chromatographic (LC) method with photodiode array detection (DAD) has been developed for the determination of glycyrrhizic acid in both the raw herb and a commercially prepared dried aqueous extract of Glycyrrhiza uralensis Fisch. ex DC. root (Zhi Gan Cao, liquorice). It was determined that extracting the raw herb in aqueous methanol (50:50 v/v) by sonication for 2 x 30 min was the most efficient sample preparation. Baseline resolution of the glycyrrhizic acid peak was achieved on a Varian Polaris RP C18-A (250 mm x 4.6 mm, 5 microm packing) column using an isocratic mobile phase consisting of 0. v aqueous phosphoric acid and acetonitrile in the ratio 60:40 v/v. Chromatograms were monitored between 200 and 400 nm for peak purity assessments, with quantitation performed at 254 nm. Glycyrrhizic acid calibration curves in the concentration range of 14-558 microg/ml were prepared on the day of analysis. Curve fitting was by the least-squares method, with correlation coefficients of >0.9998 obtained each time. The average recovery at three spike levels (50, 100, 200%) was of 95.91+/-1.05% and 98.36+/-3.45% (+/-S.D., n=7) for the spiked raw herb and dried aqueous extract respectively. The limit of detection and limit of quantitation was 0.52 and 1.72 mg/g respectively for the raw herb, and 0.75 and 2.51 mg/g respectively for the dried aqueous extract. Identity confirmation of the chromatographic peak was achieved by (-) electrospray ionisation tandem mass spectrometry. The concentration of glycyrrhizic acid in the root and dried aqueous extract was found to be 31.1+/-0.2 and 40.4+/-0.3mg/g (+/-S.D., n=7) respectively.


BMC Genomics | 2013

The Saccharomyces cerevisiae transcriptome as a mirror of phytochemical variation in complex extracts of Equisetum arvense from America, China, Europe and India

Rebekah L. Cook; James R. Hennell; Samiuela Lee; Cheang S. Khoo; Maria C Carles; Vincent J. Higgins; Suresh Govindaraghavan; Nikolaus J. Sucher

BackgroundPattern-oriented chemical profiling is increasingly being used to characterize the phytochemical composition of herbal medicines for quality control purposes. Ideally, a fingerprint of the biological effects should complement the chemical fingerprint. For ethical and practical reasons it is not possible to test each herbal extract in laboratory animals or humans. What is needed is a test system consisting of an organism with relevant biology and complexity that can serve as a surrogate in vitro system. The purpose of this study was to test the hypothesis that the Saccharomyces cerevisiae transcriptome might be used as an indicator of phytochemical variation of closely-related yet distinctly different extracts prepared from a single species of a phytogeographically widely distributed medicinal plant. We combined phytochemical profiling using chromatographic methods (HPTLC, HPLC-PDA-MS/MS) and gene expression studies using Affymetrix Yeast 2.0 gene chip with principal component analysis and k-nearest neighbor clustering analysis to test this hypothesis using extracts prepared from the phytogeographically widely distributed medicinal plant Equisetum arvense as a test case.ResultsWe found that the Equisetum arvense extracts exhibited qualitative and quantitative differences in their phytochemical composition grouped along their phytogeographical origin. Exposure of yeast to the extracts led to changes in gene expression that reflected both the similarities and differences in the phytochemical composition of the extracts. The Equisetum arvense extracts elicited changes in the expression of genes involved in mRNA translation, drug transport, metabolism of energy reserves, phospholipid metabolism, and the cellular stress response.ConclusionsOur data show that functional genomics in S. cerevisiae may be developed as a sensitive bioassay for the scientific investigation of the interplay between phytochemical composition and transcriptional effects of complex mixtures of chemical compounds. S. cerevisiae transcriptomics may also be developed for testing of mixtures of conventional drugs (“polypills”) to discover novel antagonistic or synergistic effects of those drug combinations.


Methods of Molecular Biology | 2012

Using GenBank® for Genomic Authentication: A Tutorial

James R. Hennell; Paul M. D’Agostino; Samiuela Lee; Cheang S. Khoo; Nikolaus J. Sucher

The GenBank(®) database is perhaps one of the most important repositories of genetic information. A researcher working in the field of genomic authentication must therefore be equipped with the skills needed to competently access the required information from this database whilst ultimately contributing their own data to it. This chapter presents a practical guide to using GenBank(®) to search for sequences, search and align unknown sequences using BLAST, and uploading and maintaining your own sequences. This chapter also details some other software helpful in sequence manipulation.


Archive | 2013

Genomic and Transcriptomic Profiling: Tools for the Quality Production of Plant-Based Medicines

Nikolaus J. Sucher; James R. Hennell; Maria C. Carles

A stable and controlled supply of plant-based medicines depends on the availability of high quality medicinal plants. Cultivation of medicinal plants used for the manufacture of traditional herbal medicines is considered to be a key element in the drive to modernize and internationalize traditional Chinese medicine (TCM) and has motivated the cultivation and breeding of selected Chinese medicinal plants worldwide. In parallel, several research groups have developed plant tissue culture and in vitro micropropagation techniques for the cultivation, rapid propagation, and metabolic engineering of medicinal plants. Genetic markers such as microsatellites (SSR, simple sequence repeats; short tandem repeats) and single nucleotide polymorphisms are used for marker assisted breeding and quality assessment. Next-generation sequencing (NGS) technology is rapidly becoming the method of choice for the characterization of genetic markers. An important advantage of sequencing-based approaches compared to electrophoresis-based DNA fingerprinting is that the DNA sequence is independent of the particular method that was used to generate it. Furthermore, DNA sequences can be deposited into public repositories for genetic information such as GenBank that can be searched easily using web interfaces as well as specialized bioinformatics software. Similarly, NGS can be used for transcriptomic and epigenetic studies.


Restorative Neurology and Neuroscience | 2013

Effects of a novel herbal formulation JSK on acute spinal cord injury in rats.

Caixin Su; Donald Zhang; John Truong; Cai Jiang; Sam Lee; Mariam Jarouche; James R. Hennell; Michel P. Rathbone; Nikolaus J. Sucher; Shucui Jiang

PURPOSE Acute spinal cord injury (SCI) triggers multiple cellular and molecular pathways; therapy aimed at only one pathway is unlikely to succeed. Anecdotal reports indicate that a novel herbal formulation (JSK-Ji-Sui-Kang) may enhance recovery in humans with SCI. We investigated whether JSKs therapeutic effects could be verified in a well-established SCI model in rats. METHODS Therapeutic effects of JSK were tested using a standard behavioral assessment, histological, immunochemical and microarray analysis. Phytochemical fingerprinting of JSK was performed using high performance liquid chromatography coupled with photodiode array detection and electrospray ionization-mass spectrometry. JSK or vehicle was gavaged to rats 24 hours after SCI and daily thereafter for 3 weeks. RESULTS Locomotor function significantly improved (n = 12; p < 0.05), tissue damage was reduced (p < 0.01; n = 6) and more axons and myelin were observed in JSK-treated compared with vehicle control animals. JSK significantly enhanced expression of neuroglobin, vascular endothelial growth factor and growth-associated protein 43, and reduced the expression of caspase 3, cyclooxygenase-2, RhoA (p < 0.05; n = 6) and fibrinogen (p < 0.01; n = 6). RNA microarray indicated that JSK altered transcription of genes involved in ischemic and inflammatory/immune responses and apoptosis (p < 0.05; n = 3). CONCLUSIONS JSK appears to target multiple biochemical and cellular pathways to enhance functional recovery and improve outcomes of SCI. The results provide a basis for further investigation of JSKs effects following SCI.


Archive | 2012

Plant DNA Fingerprinting and Barcoding

Nikolaus J. Sucher; James R. Hennell; Maria Carles

A brief history of taxonomy, for the most part plant oriented, is provided, which demonstrates the use of morphology early on, through the stages when different technologies became available at different times until the present use of genomic tools. Genomic authentication facilitates with greater precision than ever before the identifi cation of an organism or part thereof. In this chapter I made an attempt to stress that, in general, but more so for genomic authentication, the use of the variation inherent in taxa down to the lowest level of the hierarchy of classifi cation needs to be used to achieve a high degree of correct authentication.


Methods of Molecular Biology | 2012

DNA Fingerprinting, DNA Barcoding, and Next Generation Sequencing Technology in Plants

Nikolaus J. Sucher; James R. Hennell; Maria C. Carles


Fitoterapia | 2012

From classical taxonomy to genome and metabolome: Towards comprehensive quality standards for medicinal herb raw materials and extracts

Suresh Govindaraghavan; James R. Hennell; Nikolaus J. Sucher


Methods of Molecular Biology | 2012

Genomic DNA extraction and barcoding of endophytic fungi.

Patricia L. Diaz; James R. Hennell; Nikolaus J. Sucher

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Samiuela Lee

University of Western Sydney

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Cheang S. Khoo

University of Western Sydney

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Cheang Khoo

University of Western Sydney

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C.W. Halstead

University of Western Sydney

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John Truong

University of Western Sydney

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Maria C Carles

University of Western Sydney

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Michael J. Gray

University of Western Sydney

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