Thin Films of Liquid Media for Heterotrophic Growth and Storage Organ Development: Turmeric (Curcuma longa) as a Model Plant

Abstract

<jats:p>Geophytes store carbohydrates in modified underground shoot systems protected by a broad array of biologically active chemistry. In vitro formation of storage organs requires months in the lab instead of years in the field, when water and nutrients are correctly supplied. Liquid and agar systems in large and small vessels were compared for sugar and water use with turmeric (<jats:italic>Curcuma longa</jats:italic>) as a model plant. Small jars on a shaker were compared with large, flat-bottomed vessels containing thin films of liquid media, intermittently tilted at slight inclines that allow the advantages of liquid phase transfer with gentle agitation. Liquid culture in small vessels on a shaker yielded the most plants and liquid culture on a thin-film rocker in a large vessel yielded the largest plants. Increased and improved biomass (fresh and dry) in liquid culture compared to agar was based on greater sugar use. When large vessels of liquid media were grown for 5 and 6 months on a rocker, 400 mL of media yielded 150 to 200 g (fresh weight) of plants. Similarly, 13 to 16 g (dry weight) of plant tissue was derived from 24 g of sugar. Plants were about one-third rhizome by fresh mass. Rhizomes had greater dry and fresh weight than leaves or roots, indicating solute actively accumulated in the rhizome. The rhizomes had normal morphology, characteristic pigments and fragrance, and rhizome extracts had strong antioxidant potential. The gentle rocking action of plantlets in sugar-containing liquid medium was demonstrated to produce functional storage organs.</jats:p>

Short-term and long-term time course studies of turmeric (Curcuma longa L.) microrhizome development in vitro

“…Sunitibala et al (2001) grew rhizomes on liquid MS medium supplemented with 0.54 lM NAA, 4.65 lM kinetin, and 8% sucrose. In our laboratory's turmeric micropropagation medium (liquid MS medium modified with 6% sucrose and 1 lM BA), increased vessel size (from 180 ml jars to 6 l plastic vessels) led to increased turmeric plant size (though larger vessels with agar media did not increase plant size), and rhizomes functioned as storage organs (Adelberg and Cousins 2006). Adding 3.2 lM ancymidol to our turmeric micropropagation medium reduced fresh weight by about 10% without increasing rhizome mass.…”

“…1) (Adelberg and Cousins 2006) that produced a 1 cm pitch every 15 min (with a 1 rpm cam). Each vessel contained 200 ml of medium of the same formulation and treatment combinations as used in the short-term time course.…”

In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

“…Curcuma longa L. accession L 35–1 was supplied by University of Arizona, Southwest Center for Natural Products Research and Commercialization (UA Herbarium 375,742, ARIZ). Quiescent shoot tips were separated from rhizomes then sterilized and initiated in stage I as previously described by Cousins and Adelberg [ 16 ]. Stage II buds were maintained during five years by routine subculture (5-week periods) on 33 ml of modified MS liquid medium on a 100 rpm gyratory shaker, in 180 ml cylindrical glass vessels, with Magenta B cap closures (Magenta Corp, Chicago IL, USA), 1 μM BA, 60 g sucrose per liter, pH 5.7.…”

“…Dried rhizomes of turmeric ( Curcuma longa L.), a perennial herb, have economic value as a spice, dye, and a source of therapeutic and bioactive metabolites [ 15 ]. Turmeric rhizomes with strong anti-oxidant properties were developed in large volume (2.5 l) bioreactor cultures when sucrose and water were added to prolong the culture period over 15 to 24 weeks [ 16 ], [ 14 ].…”

The Biotechnology of Turmeric

“…Prathanturarug et al (2005) report a preculture on liquid MS with TDZ prior to transfer onto plain MS media to enhance multiple shootlet formation and also the application of a temporary immersion culture system to reduce the cost of plantlet production during mass multiplication. Adelberg and Cousins (2006) report that use of liquid media in large culture vessel with gentle tilting agitation can give bigger plantlets, while small vessels on a shaker gave higher number of plantlets. Increased biomass formation was thus reported in liquid medium as compared to solid medium.…”