Plants have long been used as sources of pharmaceuticals or other commercial products. Many of these products are difficult to synthesize at affordable prices. Furthermore, the extensive testing that is required of synthetic products in order to meet safety standards, compared to requirements for natural products, has stimulated interest in replacing many synthetic chemicals, especially food additives, by natural plant extracts. "Plantations" of medicinal plants, as with any cropped plants, are vulnerable to diminished yields due to outbreaks of disease or unfavorable changes in growing conditions, resulting in considerable economic loss to growers. Furthermore, some plants can not be grown as crops in the geographical areas where there is the most need for their products. In such cases, an alternative means of obtaining natural products from plants is through plant tissue culture. The fruit and leaves of Ficus carica (the edible fig) produce many polyphenolic antioxidants of potential therapeutic value. However, the plant is vulnerable to fig mosaic virus disease, and does not grow well out of semitropical and Mediterranean climates. In this work, Ficus carica tissue cultures were investigated as an alternate source of antioxidant polyphenols. It is well know that ntioxidants have anticarcinogenic, antibacterial, and antiviral properties and can be used as food supplements. In an effort to determine culture conditions that resulted in the production of polyphenols comparable to those produced by intact plants, chemical and physical factors that affect yield, such as basal media composition, light intensity, temperature, growth hormones, and elicitors were tested.
As a result of this research, callus cultures were developed that contained an average of 4.26% polyphenols of their dry weight. Analysis based on TLC and HPLC, showed that the main antioxidants found in callus tissue are apigenin, isoquercitrin, astragalin (kaempferol glycoside), rutin, emodin, cyanidin, caffeic acid, tannic acid, chlorogenic acid, quercitin, kaempferol, taxifolin, catechin and epichatechin. These results show that tissue cultures of Ficus carica can be used successfully for production of antioxidant compounds used as food supplements. It is also shown that tissue cultures initiated from vegetative tissue can produce polyphenols usually found in fig fruit as well as in leaves and other parts of the plant.