Somatic embryogenic calli were obtained from different native citrus species in Jeju island, South Korea. Undeveloped ovules were cultured on 5 different media, respectively; MSI (MS, modified, with the addition of malt extract 500 mg･L-1 and sucrose 50 g･L-1 and agar 2 g･L-1), MSII (MS, modified, with the addition of malt extract 500 mg･L-1 , kinetin 1 mg･L-1 and sucrose 50 g･L-1 and agar 2 g･L-1), MSIII (MS, modified, with the addition of malt extract 500 mg･L-1, 6-benzyladenine, 3 mg･L-1 and sucrose 50 g･L-1 and agar 2 g･L-1), EME-S (MT, modified, with the addition of malt extract 500 mg･L-1 and sucrose 50 g･L-1 and agar 2 g･L-1), 1/2 EME-S (half concentration of MT marcronutrients, half concentratrion of BH3 marcronutrients, malt extract 500 mg･L-1, glutamine 1.55 g･L-1 and sucrose 50 g･L-1 and agar 2 g･ L-1). Embryogenic calli were induced in the surface of undeveloped ovules in different manners, depending on citrus species and culture conditions. Somatic embryos developed into plantlets with a high frequency. Citrus embryogenic calli can be applied widely to somatic hybridization, genetic transformation, and in vitro germplasm conservation

Miraculin can modify a sour taste into a sweet taste and is an alternative to traditional sweeteners. Mirculin gene was introduced into the Miyagawa Wase Satsuma mandarin (Citrus unshiu Marc.) callus by Agrobacterum-mediated transformation to produce citrus transgenic plant. Transgenic plant candidates were selected via hygromycin resistance. Transformation was confirmed by Polymerase Chain Reaction, Southern blotting, and Western blot analysis. Expression of this gene in transgenic citrus resulted in the accumulation of miraculin protein in the leaves. Multiple Shoots of transgenic citrus planets were micrografted onto trifoliate rootstocks in the sterile soil. Plants were established in the greenhouse 2 years after planting.

Cinnamyl alcohol dehydrogenase (CAD) catalyzes cinnamyl aldehydes into cinnamyl alcohols, the final step in lignin biosynthesis. In this studied the purification, identification and characterization of a new cinnamyl alcohol dehydrogenase gene isolated from Citrus platymamma hort. Ex Tanaka. We expressed CAD potential gene in E.coli and then characterized its features in variety of specificity aldehydes substrates. The recombinant CAD protein was shown highest efficiently catalytic toward cinnamyl and coniferyl aldehydes and the shown lowest efficiently catalytic toward sinapyl aldehydes. We used a new improved analytical HPLC method in CAD enzymatic assay for fast and accurately measurement in various aldehydes substrates. In conclusion, our studies indicated the enzymatic activity of cDNA cloned CAD protein from Citrus platymamma hort. Ex Tanaka.