• Korean Journal of Plant Tissue Culture
• /
• v.27 no.4
• /
• pp.269-282
• /
• 2000

Benzylisoquinoline alkaloids are a diverse group of natural products that include many pharmacologically active compounds produced in a limited number of plant families. Despite their complexity, intensive biochemical research has extended our knowledge of the chemistry and enzymology of many important benzylisoquinoline alkaloid pathways, such as those leading to the analgesic drugs morphine and codeine, and the antibiotics sanguinarine and berberine. The use of cultured plant cells as an experimental system has facilitated the identification and characterization of more than 30 benzylisoquinoline alkaloid biosynthetic enzymes, and the molecular cloning of the genes that encode at least 8 of these enzymes. The recent expansion of biochemical and molecular technologies has creat-ed unique opportunities to dissect the mechanisms involved in the regulation of benzylisoquinoline alkaloid biosynthesis in plants. Research has suggested that product accumulation is controlled by the developmental and inducible regulation of several benzylisoquinoline alkaloid biosynthetic genes, and by the subcellular compartmentation of biosynthetic enzymes and the intracellular localization and trafficking of pathway intermediates. In this paper, we review our current understanding of the biochemistry, cell biology, and molecular regulation of benzylisoquinoline alkaloid biosynthesis in plants. We also summarize our own research activities, especially those related to the establishment of protocols for the genetic transformation of benzylisoquinoline alkaloid-producing species, and the development of metabolic engineering strategies in these plants.

• Korean Journal of Medicinal Crop Science
• /
• v.12 no.5
• /
• pp.428-435
• /
• 2004

Alkaloid producing species of plants have long been a major component of the medicinal social and magico-religious aspects of human culture. A diverse array of biological activities has been attributed to different alkaloids including numerous members of benzylisoquinoline family of alkaloids. For biotechnological approaches of alkaloid biosynthesis in poppy family, plant regeneration protocol through somatic embryogenesis or shoot organogenesis is a first step. This paper describes the methods and applications of plant regeneration of poppy family.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2005.11a
• /
• pp.22-26
• /
• 2005

Nicotine is most familiar to us as a principal pharmacologically active component of cigarettes. This alkaloid is synthesized in the root in response to insect damage and then transported to the aerial parts of tobacco plants. Here I overview enzymes and genes involved in nicotine biosynthesis, and regulatory mechanisms of gene expression involving the NIC regulatory loci and jasmonic acid.

• Archives of Pharmacal Research
• /
• v.20 no.5
• /
• pp.510-512
• /
• 1997

The effects of noscapine a phthalide isoquinoline alkaloid, on dopamine biosynthesis and tyrosine hydroxylase (TH) activity in PC12 cells were investigated. Noscapine showed 74.6% inhibition on dopamine content in PC12 cells at a concentration of $20{\mu}M.$ $IC_{50}$ of noscapine was $6.8{\mu}M.$ TH activity was inhibited by the treatment of noscapine in PC12 cells (20.9% inhibition at 20 .mu.M). Therefore, the inhibition of TH activity by noscapine might be involved in at least one component of the reduction of dopamine biosynthesis in PC12 cells.

• Journal of Plant Biotechnology
• /
• v.29 no.3
• /
• pp.199-207
• /
• 2002

The tropane alkaloids hyoscyamine (its racemic form being atropine) and scopolamine are used medicinally as anticholinergic agents that act on the parasympathetic nerve system. Because they differ in their actions on the central nervous system, currently there is a 10-fold higher commercial demand for scopolamine, in the N-butylbromide form, than there is for hyoscyamine and atropine combined. Several solanaceous species have been used as the commercial sources of these alkaloids, but the scopolamine contents in these plants often are much lower than those of hyoscyamine. For this reason there has been long-standing interest in increasing the scopolamine contents of cultivated medicinal plants. Naturally occurring and artificial interspecific hybrids of Duboisia have high scopolamine contents and are cultivated as a commercial source of scopolamine in Australia and other countries. Anther culture combined with conventional interspecific hybridization also has been used to breed high scopolamine-containing plants in the genera Datura and Hyoscyamus, but without much success. The use of recombinant DNA technology for the manipulation of metabolic processes in cells promises to provide important contributions to basic science, agriculture, and medicine. In this review, I introduce on the enzymes and genes involved in tropane alkaloid biosynthesis and current progress in metabolic engineering approaches for tropane alkaloid, especially scopolamine, production.

• Archives of Pharmacal Research
• /
• v.19 no.4
• /
• pp.258-260
• /
• 1996

Palmatine, an protoberberine isoquinoline alkaloid, has been found to inhibit dopamine biosynthesis by reducing tyrosine hydroxylase (TH) activity in PC12 cells (Lee and Kim, 1996). We have therefore investigated the effects of palmatine on bovine adrenal TH. Palmatine showed a mild inhibition on bovine adrenal TH (36.4% inhibition at concentration of $200\muM$). Bovine adrenal TH was inhibited competitively by palmatine with a substrate L-tyrosine. The Ki value was found to be 0.67 mM. This result suggests that the inhibition of TH activity by palmatine may be partially involved in the reduction of dopamine biosynthesis in PC12 cells.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.79.3-80
• /
• 2003

The effects of anonaine, an aporphine isoquinoline alkaloid, on dopamine biosynthesis and L-DOPA-induced neurotoxicity in PC12 cells were investigated. Treatment of PC12 cells with 0.05 ${\mu}$M anonaine showed a significant inhibition of dopamine content. The IC$\sub$50/ value of anonaine was 0.05 ${\mu}$M. Under the same conditions, 0.05 ${\mu}$M anonaine also inhibited tyrosine hydroxylase (TH) activity at 24 h (62.0% inhibition of the control level). TH mRNA levels were also decreased by the treatment with anonaine. (omitted)

• Proceedings of the Korea Contents Association Conference
• /
• 2018.05a
• /
• pp.545-546
• /
• 2018

In this study identify potentially new alkaloids predicted from transcription information will provide insight into the pathways and molecular regulation of alkaloid biosynthesis.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.5
• /
• pp.748-756
• /
• 2018

Biofilms are of vital significance in bioconversion and biotechnological processes. In this work, sugarcane molasses was used to enhance biofilms for the improvement of the production of fumigaclavine C (FC), a conidiation-associated ergot alkaloid with strong anti-inflammatory activities. Biofilm formation was more greatly induced by the addition of molasses than the addition of other reported biofilm inducers. With the optimal molasses concentration (400 g/l), the biofilm biomass was 6-fold higher than that with sucrose, and FC and conidia production was increased by 5.8- and 3.1-fold, respectively. Moreover, the global secondary metabolism regulatory gene laeA, FC biosynthetic gene fgaOx3, and asexual central regulatory genes brlA and wetA were upregulated in molasses-based biofilms, suggesting the upregulation of both asexual development and FC biosynthesis. This study provides novel insight into the stimulatory effects of molasses on biofilm formation and supports the widespread application of molasses as an inexpensive raw material and effective inducer for biofilm production.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.139.1-139.1
• /
• 2003

The effects of liriodenine, an aporphine isoquinoline alkaloid, on dopamine biosynthesis and L-DOPA-induced neurotoxicity in PC12 cells were investigated. Treatment of PC12 cells with liriodenine at 10 $\mu\textrm{M}$ showed 33.6％ inhibition of dopamine content decreased at 3 h and reached a minimal level at 12 h after the exposure to liriodenine at 10 $\mu\textrm{M}$. (omitted)