Coptis rhizome (Japanese name woren), belonging to the Ranunclaceae, is very commonly used in Japanese traditional medicine as antipyretic, antidote and an-tidysentery. The cultivation of the rhizome of Coptis plant grows very slowly and takes 5-6 years before use as raw material or as a source of berberine from the rhizome. Its rootstock and fibrous roots contain much berberine and other minor protoberberine alkaloids. Berberine is an useful antibacterial agent, and has stomachic and anti-inflammatory effects. Berberine can be obtained from Coptis rhizome and Phellodendron bark and has a wide market in Japan and East Asia.
It is of pharmaceutical significance to investigate callus culture of this plant for berberine production. Several researchers have been working on its production.
Coptis () has 15 species of small herbs with perennial root stocks distributed in the temperate regions of the northern hemisphere. The following species are used medicinally: C. japonica in Japan, C. chinensis in China, C. teeta in India and C. trifolia in North America. The powdered rhizome or an extract of C. japonica is a bitter stomachic and astringent. It has been used as remedy for severe headache; a concentrated solution of the roasted and powdered rhizome is rubbed on scabies. Ointments containing the rhizome and leaf may be employed for eczema marginatum with fewer side-effects than some other ointments; however, in vitro antifungal activity and clinical efficacy showed no significant correlation. The rhizome of C. chinensis is bitter, and has a cooling effect; it is used to treat fever, nausea, thirst, haemorrhages and conjuctivitis; and also, in a special preparation with fresh ginger or fruit of Evodia, to treat nausea and painful blisters in the mouth. It is an effective antibiotic for bacillary dysentery, a remedy for inflammation of the alimentary canal and for diabetes; it is a bitter stomachic.
The rhizome of C. teeta is an all-round tonic and stomachic medicine. It has been found to produce excellent effects in debility, convalescence after fevers and other debilitating diseases, atonic dyspepsia and in mild forms of intermittent fevers. C. groenlandica promotes digestion, counteracts dyspepsia and strengthens the visora: the bitter principle is said to be a good substitute for that found in Gentiana and Quassia ().
Reported alkaloid constituents of Coptis rhizome are berberine, coptisine, worenine, palmatine, columbamine, jatrorrhizine, epiberberine groenlandicine, berberastine and magnoflorine.
There is a very efficient productivity of berberine as compared with the cultivation of the intact plant, as regards the culture period and berberine content that the berberine contained from callus of 11 medium in one cultured period is approximately equal to the value of the original plant rhizome cultivated during 5-6 years. Therefore, cell suspension culture of C. japonica has good possibilities to produce the berberine on a large scale. Moreover, the addition of gibberellin on C. japonica cell cultures showed the remarkable increase of the berberine production, therefore the phytohormones are important factors in the production of secondary metabolites and further research on phytohormones is necessary. It is also a useful procedure that immobilized Coptis cells excreted berberine into the medium in a bioreactor and this seems to promise success.
Regeneration from callus was stimulated in MS medium containing 2,4-D and kin and numerous somatic embryoid were produced during about 6 weeks. When the embryoids were transferred to MS medium containing IAA, its regeneration capacity increased and formed the root- and shoot-bearing nodules.
The regenerated plantlets were transferred to MS medium without growth regulators and cultured under light to raise green leaves and yellow root and grew vigorously when cultivated on the soil. If these plantlets are utilized for propagation of Coptis plants, there is a possibility that the time of cultivation be shortened by 1-2 years.
Selections from the book: “Medicinal and Aromatic Plants II”, 1989.