Enzymes and diterpenes in latices of Euphorbia species

Latex is an aqueous suspension or emulsion of various kinds of particles borne within living cells. In the complex emulsion/suspension proteins, alkaloids, starches, sugars, oil, tannins, resins, and gums are found. Latex is wide spread in plants. The presence of enzymes in latices from plants of diverse families has been known for many years. The functions of these proteins which come from different genetic resources have not been elucidated. One possible function of proteases is the degradation of proteins during laticifer development or promotion of coagulation. Latex itself may act to shield the cambial meristem and the contents of the sieve tubes from predators, or to ward off parasites or pathogens. Therefore, it seems reasonable to assume that secondary natural products and enzymes needed for such purposes are present in latex [1]. Latex proteases have been found to protect ripening fruits against plant pathogens such as insects and fungi [2]. The presence of bacteriolytic activity in latices of different plants confirms the fact that they act in unison. Latices of Euphorbia species contain a broad spectrum of proteolytic enzymes. Beside these types of enzymes biochemical investigations demonstrated also the presence of chitinases and lysozyme expressing antibacterial activity. Another main component in the latex of Euphorbiaceae are diterpene esters which induce inflammation and known for their tumor promoting effects [3]. In our investigations we tried to compare if a high lysozyme and chitinase activity in the latices of different species correlate with a low concentration or absence of diterpene esters. Because of the rather harmful effect of diterpenes they restrict therapeutic and technical application of latices of Euphorbia species.

Keywords: Euphorbia, latex

References:

[1] Liggieri C, Arribére MC, Trejo SA, Canals F, Avilés FX, Priolo NS. Purification and biochemical characterization of Asclepain c I from the latex of Asclepias curassavica L. Protein J 2004; 23: 403 – 411

[2] Patel BK, Jagannadham MV. A high cysteine containing thiol porteinase from the latex of Ervatamia heyneana: purification and comparison with Ervatamin B and C from Ervatamia coronaria. J Agric Food Chem 2003; 51: 6326 – 6334

[3] Shi QW, Su XH, Kiyota H. Chemical and pharmacological research of the plants in genus Euphorbia. Chem Rev 2008; 108: 4295 – 327