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Papers by Natascha Techen
The construction of microsatellite-enriched libraries is an indispensable tool to search for mole... more The construction of microsatellite-enriched libraries is an indispensable tool to search for molecular markers as complete genome sequences are still not available for the majority of species of interest. Numerous protocols are available in the literature for the construction of these libraries; however, sometimes their low efficiency or lack of optimization in the protocols can restrict their efficacy. We have designed and tested various adapters and ligation methods; we also tested oligo-repeat combinations and hybridization temperatures, and created libraries with this new protocol for four organisms: Ipomoea batatas (L.) Lam, Chionanthus retusus Lindley & Paxton, Rotylenchulus reniformis Linford & Olivera and Puccinia kuehnii W. Krü ger. The number of microsatellites detected for these species ranged from 2494 to 3919 per Mb of nonredundant sequence, that was 0.86 and 1.53 microsatellites per contig, with 37-66% of di-nucleotide motifs and 21-49% of tri-to octa-nucleotide repeats combined. A simplified protocol is provided for the successful generation of SSR-enriched libraries.
Quality and Quantity of DNA from Fresh and Long Term Stored Samples
Planta Medica, 2010
Journal of Herbs, Spices & Medicinal Plants, 2009
Hoodia gordonii, an appetite suppressant, is used extensively as a botanical dietary supplement. ... more Hoodia gordonii, an appetite suppressant, is used extensively as a botanical dietary supplement. Microscopy and molecular genetic procedures are provided for identification and differentiation between H. gordonii, Opuntia ficus indica, and other related Hoodia species.
Phytochemistry, 2011
Tripterygium wilfordii Hook.f., known as Leigongteng (Thunder God Vine) in traditional Chinese me... more Tripterygium wilfordii Hook.f., known as Leigongteng (Thunder God Vine) in traditional Chinese medicine, has attracted much attention for its applications in relieving autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus, and for treating cancer. Molecular analyses of the ITS and 5S rDNA sequences indicate that T. hypoglaucum and T. doianum are not distinct from T. wilfordii, while T. regelii should be recognized as a separate species. The results also demonstrate potential value of rDNA sequence data in forensic detection of adulterants derived from Celastrus angulatus in commercial samples of Leigongteng.
Planta Medica, 2009
V Chinese Star anise, Illicium verurn Hook, is a well known spice in many cultures and has also b... more V Chinese Star anise, Illicium verurn Hook, is a well known spice in many cultures and has also been used to treat infant colic. Recent publications report that Chinese Star anise might be adulterated with the toxic Japanese Star anise, !lliciurn anisaturn L We have developed a molecular method that helps with the detection of I.
Planta Medica, 2010
A protocol was developed for in vitro propagation of an elite genotype of Curcuma longa (cv Roma)... more A protocol was developed for in vitro propagation of an elite genotype of Curcuma longa (cv Roma) using axillary buds from unsprouted rhizomes. The explant produced multiple shoots when cultured on MS basal medium supplemented with varying combinations and concentrations of Benzyladenine, Kinetin,α Napthalene, Acetic acid, Indole-3-acetic acid and Adenine sulphate. Medium containing BA (3mg/l) was found to be optimum for micropropagation and conservation of C. longa plantlets. The genetic stability of the micropropagated clones was evaluated over 26 months in culture using cytophotometry and Random Amplified Polymorphic DNA (RAPD) analysis. Cytophotometry analysis revealed unimodal DNA distribution with 4C peak and RAPD analysis revealed monomorphic bands in all in vitro grown plants of C. longa, thus confirming genetic uniformity among somaclones of C. longa. This study is of high significance as these cultures are currently being used as source of disease free planting material for commercial utilization.
Genomic Profiling of Cannabis sativa L
Planta Medica, 2009
A Rapid Microdistillation Method for the Texas and Turkish Salvia Species and Their Genetic Profiles
Planta Medica, 2009
Molecular Analysis of Genetic Stability of Micropropagated Plants of Cannabis sativa L. using ISSR Markers
Planta Medica, 2009
The Use of Polymerase Chain Reaction (PCR) for the Identification of Ephedra DNA in Dietary Supplements
Planta Medica, 2006
As part of a continuing research effort to develop chemical and genetic authentication profiles o... more As part of a continuing research effort to develop chemical and genetic authentication profiles of botanicals, an investigation was performed with the goal to detect, identify and verify Ephedra sinica Stapf DNA in dietary supplements such as plant mixtures and tablets/capsules. We amplified and sequenced the chloroplast psbA-trnH spacer from 21 Ephedra spp. and from two of their closest relatives, Gnetum gnemon L. and Welwitschia mirabilis Hook. Based on sequence comparisons, we identified regions unique to all of the Ephedra spp. samples analyzed. We concluded that the psbA-trnH spacer sequence could be used as a molecular marker. Based on this spacer sequence, we designed Ephedra spp.-specific primers that can help to identify Ephedra spp. DNA in plant mixtures containing as little as 1/1,000 part of Ephedra spp. tissue. We used a DNA extraction method that allows for quick DNA isolation from plant mixtures for PCR analysis.
Molecular Ecology Resources, 2010
The construction of microsatellite-enriched libraries is an indispensable tool to search for mole... more The construction of microsatellite-enriched libraries is an indispensable tool to search for molecular markers as complete genome sequences are still not available for the majority of species of interest. Numerous protocols are available in the literature for the construction of these libraries; however, sometimes their low efficiency or lack of optimization in the protocols can restrict their efficacy. We have designed and tested various adapters and ligation methods; we also tested oligo-repeat combinations and hybridization temperatures, and created libraries with this new protocol for four organisms: Ipomoea batatas (L.) Lam, Chionanthus retusus Lindley & Paxton, Rotylenchulus reniformis Linford & Olivera and Puccinia kuehnii W. Krü ger. The number of microsatellites detected for these species ranged from 2494 to 3919 per Mb of nonredundant sequence, that was 0.86 and 1.53 microsatellites per contig, with 37-66% of di-nucleotide motifs and 21-49% of tri-to octa-nucleotide repeats combined. A simplified protocol is provided for the successful generation of SSR-enriched libraries.
Journal of Ethnopharmacology, 2010
Aim of the study: The antitussive Chinese herb Madouling derived from Aristolochia species is ban... more Aim of the study: The antitussive Chinese herb Madouling derived from Aristolochia species is banned due to aristolochic acid-induced nephropathy. A substitute is found dispensed as Madouling in Taiwan. This study aims to determine the source plant and verify the antitussive properties of the Madouling substitute used in Taiwan. Materials and methods: Forensically informative nucleotide sequencing (FINS) approach based on the trnL-trnF and psbA-trnH regions was applied to facilitate identification of the genuine species and substitute. The antitussive effect of both genuine Madouling and the substitute were evaluated in guinea pigs. Results: FINS approach based on the trnL-trnF and psbA-trnH regions readily identified the sample of Madouling in Taiwan to the seeds of Cardiocrinum giganteum var. yunnanense. Ethanol extracts of the substitute showed significant antitussive properties in guinea pigs. Conclusion: Cardiocrinum seeds may have potential as a replacement of Aristolochia fruits.
Biotechnology Letters, 2011
The increasing utilization of synthetic (encapsulated) seeds for germplasm conservation and propa... more The increasing utilization of synthetic (encapsulated) seeds for germplasm conservation and propagation necessitates the assessment of genetic stability of conserved propagules following their plantlet conversion. We have assessed the genetic stability of synthetic seeds of Cannabis sativa L. during in vitro multiplication and storage for 6 months at different growth conditions using inter simple sequence repeat (ISSR) DNA fingerprinting. Molecular analysis of randomly selected plants from each batch was conducted using 14 ISSR markers. Of the 14 primers tested, nine produced 40 distinct and reproducible bands. All the ISSR profiles from in vitro stored plants were monomorphic and comparable to the mother plant which confirms the genetic stability among the clones. GC analysis of six major cannabinoids [D 9 -tetrahydrocannabinol, tetrahydrocannabivarin, cannabidiol, cannabichromene, cannabigerol and cannabinol] showed homogeneity in the re-grown clones and the mother plant with insignificant differences in cannabinoids content, thereby confirming the stability of plants derived from synthetic seeds following 6 months storage.
Chemical characterization and genomic profiling of Achillea biebersteinii from various localities in Central Turkey
Because of the increasing demand for herbal remedies and for authentication of the source materia... more Because of the increasing demand for herbal remedies and for authentication of the source material, it is vital to provide a single database containing information about authentic plant materials and their potential adulterants. The database should provide DNA barcodes for data retrieval and similarity search. In order to obtain such barcodes, several molecular methods have been applied to develop markers that aid with the authentication and identification of medicinal plant materials. In this review, we discuss the genomic regions and molecular methods selected to provide barcodes, available databases and the potential future of barcoding using next generation sequencing.
The construction of microsatellite-enriched libraries is an indispensable tool to search for mole... more The construction of microsatellite-enriched libraries is an indispensable tool to search for molecular markers as complete genome sequences are still not available for the majority of species of interest. Numerous protocols are available in the literature for the construction of these libraries; however, sometimes their low efficiency or lack of optimization in the protocols can restrict their efficacy. We have designed and tested various adapters and ligation methods; we also tested oligo-repeat combinations and hybridization temperatures, and created libraries with this new protocol for four organisms: Ipomoea batatas (L.) Lam, Chionanthus retusus Lindley & Paxton, Rotylenchulus reniformis Linford & Olivera and Puccinia kuehnii W. Krü ger. The number of microsatellites detected for these species ranged from 2494 to 3919 per Mb of nonredundant sequence, that was 0.86 and 1.53 microsatellites per contig, with 37-66% of di-nucleotide motifs and 21-49% of tri-to octa-nucleotide repeats combined. A simplified protocol is provided for the successful generation of SSR-enriched libraries.
Quality and Quantity of DNA from Fresh and Long Term Stored Samples
Planta Medica, 2010
Journal of Herbs, Spices & Medicinal Plants, 2009
Hoodia gordonii, an appetite suppressant, is used extensively as a botanical dietary supplement. ... more Hoodia gordonii, an appetite suppressant, is used extensively as a botanical dietary supplement. Microscopy and molecular genetic procedures are provided for identification and differentiation between H. gordonii, Opuntia ficus indica, and other related Hoodia species.
Phytochemistry, 2011
Tripterygium wilfordii Hook.f., known as Leigongteng (Thunder God Vine) in traditional Chinese me... more Tripterygium wilfordii Hook.f., known as Leigongteng (Thunder God Vine) in traditional Chinese medicine, has attracted much attention for its applications in relieving autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus, and for treating cancer. Molecular analyses of the ITS and 5S rDNA sequences indicate that T. hypoglaucum and T. doianum are not distinct from T. wilfordii, while T. regelii should be recognized as a separate species. The results also demonstrate potential value of rDNA sequence data in forensic detection of adulterants derived from Celastrus angulatus in commercial samples of Leigongteng.
Planta Medica, 2009
V Chinese Star anise, Illicium verurn Hook, is a well known spice in many cultures and has also b... more V Chinese Star anise, Illicium verurn Hook, is a well known spice in many cultures and has also been used to treat infant colic. Recent publications report that Chinese Star anise might be adulterated with the toxic Japanese Star anise, !lliciurn anisaturn L We have developed a molecular method that helps with the detection of I.
Planta Medica, 2010
A protocol was developed for in vitro propagation of an elite genotype of Curcuma longa (cv Roma)... more A protocol was developed for in vitro propagation of an elite genotype of Curcuma longa (cv Roma) using axillary buds from unsprouted rhizomes. The explant produced multiple shoots when cultured on MS basal medium supplemented with varying combinations and concentrations of Benzyladenine, Kinetin,α Napthalene, Acetic acid, Indole-3-acetic acid and Adenine sulphate. Medium containing BA (3mg/l) was found to be optimum for micropropagation and conservation of C. longa plantlets. The genetic stability of the micropropagated clones was evaluated over 26 months in culture using cytophotometry and Random Amplified Polymorphic DNA (RAPD) analysis. Cytophotometry analysis revealed unimodal DNA distribution with 4C peak and RAPD analysis revealed monomorphic bands in all in vitro grown plants of C. longa, thus confirming genetic uniformity among somaclones of C. longa. This study is of high significance as these cultures are currently being used as source of disease free planting material for commercial utilization.
Genomic Profiling of Cannabis sativa L
Planta Medica, 2009
A Rapid Microdistillation Method for the Texas and Turkish Salvia Species and Their Genetic Profiles
Planta Medica, 2009
Molecular Analysis of Genetic Stability of Micropropagated Plants of Cannabis sativa L. using ISSR Markers
Planta Medica, 2009
The Use of Polymerase Chain Reaction (PCR) for the Identification of Ephedra DNA in Dietary Supplements
Planta Medica, 2006
As part of a continuing research effort to develop chemical and genetic authentication profiles o... more As part of a continuing research effort to develop chemical and genetic authentication profiles of botanicals, an investigation was performed with the goal to detect, identify and verify Ephedra sinica Stapf DNA in dietary supplements such as plant mixtures and tablets/capsules. We amplified and sequenced the chloroplast psbA-trnH spacer from 21 Ephedra spp. and from two of their closest relatives, Gnetum gnemon L. and Welwitschia mirabilis Hook. Based on sequence comparisons, we identified regions unique to all of the Ephedra spp. samples analyzed. We concluded that the psbA-trnH spacer sequence could be used as a molecular marker. Based on this spacer sequence, we designed Ephedra spp.-specific primers that can help to identify Ephedra spp. DNA in plant mixtures containing as little as 1/1,000 part of Ephedra spp. tissue. We used a DNA extraction method that allows for quick DNA isolation from plant mixtures for PCR analysis.
Molecular Ecology Resources, 2010
The construction of microsatellite-enriched libraries is an indispensable tool to search for mole... more The construction of microsatellite-enriched libraries is an indispensable tool to search for molecular markers as complete genome sequences are still not available for the majority of species of interest. Numerous protocols are available in the literature for the construction of these libraries; however, sometimes their low efficiency or lack of optimization in the protocols can restrict their efficacy. We have designed and tested various adapters and ligation methods; we also tested oligo-repeat combinations and hybridization temperatures, and created libraries with this new protocol for four organisms: Ipomoea batatas (L.) Lam, Chionanthus retusus Lindley & Paxton, Rotylenchulus reniformis Linford & Olivera and Puccinia kuehnii W. Krü ger. The number of microsatellites detected for these species ranged from 2494 to 3919 per Mb of nonredundant sequence, that was 0.86 and 1.53 microsatellites per contig, with 37-66% of di-nucleotide motifs and 21-49% of tri-to octa-nucleotide repeats combined. A simplified protocol is provided for the successful generation of SSR-enriched libraries.
Journal of Ethnopharmacology, 2010
Aim of the study: The antitussive Chinese herb Madouling derived from Aristolochia species is ban... more Aim of the study: The antitussive Chinese herb Madouling derived from Aristolochia species is banned due to aristolochic acid-induced nephropathy. A substitute is found dispensed as Madouling in Taiwan. This study aims to determine the source plant and verify the antitussive properties of the Madouling substitute used in Taiwan. Materials and methods: Forensically informative nucleotide sequencing (FINS) approach based on the trnL-trnF and psbA-trnH regions was applied to facilitate identification of the genuine species and substitute. The antitussive effect of both genuine Madouling and the substitute were evaluated in guinea pigs. Results: FINS approach based on the trnL-trnF and psbA-trnH regions readily identified the sample of Madouling in Taiwan to the seeds of Cardiocrinum giganteum var. yunnanense. Ethanol extracts of the substitute showed significant antitussive properties in guinea pigs. Conclusion: Cardiocrinum seeds may have potential as a replacement of Aristolochia fruits.
Biotechnology Letters, 2011
The increasing utilization of synthetic (encapsulated) seeds for germplasm conservation and propa... more The increasing utilization of synthetic (encapsulated) seeds for germplasm conservation and propagation necessitates the assessment of genetic stability of conserved propagules following their plantlet conversion. We have assessed the genetic stability of synthetic seeds of Cannabis sativa L. during in vitro multiplication and storage for 6 months at different growth conditions using inter simple sequence repeat (ISSR) DNA fingerprinting. Molecular analysis of randomly selected plants from each batch was conducted using 14 ISSR markers. Of the 14 primers tested, nine produced 40 distinct and reproducible bands. All the ISSR profiles from in vitro stored plants were monomorphic and comparable to the mother plant which confirms the genetic stability among the clones. GC analysis of six major cannabinoids [D 9 -tetrahydrocannabinol, tetrahydrocannabivarin, cannabidiol, cannabichromene, cannabigerol and cannabinol] showed homogeneity in the re-grown clones and the mother plant with insignificant differences in cannabinoids content, thereby confirming the stability of plants derived from synthetic seeds following 6 months storage.
Chemical characterization and genomic profiling of Achillea biebersteinii from various localities in Central Turkey
Because of the increasing demand for herbal remedies and for authentication of the source materia... more Because of the increasing demand for herbal remedies and for authentication of the source material, it is vital to provide a single database containing information about authentic plant materials and their potential adulterants. The database should provide DNA barcodes for data retrieval and similarity search. In order to obtain such barcodes, several molecular methods have been applied to develop markers that aid with the authentication and identification of medicinal plant materials. In this review, we discuss the genomic regions and molecular methods selected to provide barcodes, available databases and the potential future of barcoding using next generation sequencing.