P. Gómez

Citrus limon: a source of flavonoids of pharmaceutical interest

Some of the medicinal properties of lemons are due to the flavonoids they contain since they are involved in many biological activities and have many health-related functions. The levels of the principal flavanones and flavone found in different cultivars of Citrus limon, are analysed in an attempt to identify the most interesting as regards the content of such secondary compounds. The results show that the immature fruits from cultivars Lisbon and Fino-49 are ideal for obtaining the flavanone hesperidin, while the mature fruits of cultivar Fino-49 and the leaves of cultivar Eureka are the most interesting for obtaining the flavone diosmin and the flavanone eriocitrin.

Effect of ethylene on diosgenin accumulation in callus cultures of Trigonella foenum-graecum L.

Abstract This paper studies the effects of different concentrations of ethephon (an ethylene-releasing compound) on the level of the steroidal sapogenin, diosgenin, in callus cultures of Trigonella foenum-graecum . The results show that diosgenin synthesis and/or accumulation was stimulated by 5, 15, and 25 ppm ethephon. This was particularly true in the case of the 25 ppm treatment when an increase of 195% was observed. Concentrations of 50 ppm and 100 ppm reduced diosgenin levels. The following morphological and ultrastructural changes were observed in the callus cells of T. foenum-graecum treated with ethephon: increased cell diameter, decreased cell packing (for all concentrations assayed), increased cytoplasmatic density (25 ppm treatment) and alteration of the membrane structures (50 and 100 ppm).

Ultrastructural changes and diosgenin content in cell suspensions of Trigonella foenum-graecum L. by ethylene treatment

This paper studies the effect of different concentrations of ethephon (an ethylene releasing compound) on the level of the steroidal sapogenin diosgenin in cell suspensions of Trigonella foenum-graecum L. The results reveal that diosgenin synthesis and/or accumulation was stimulated by 5 ppm ethephon treatment, an increase of 126% being observed, while concentrations of 25 ppm and 50 ppm reduced the levels of this secondary compound. Changes in the isopentenyl diphosphate isomerase activity, increased cell diameter, decreased cell packing (with all the ethephon concentrations assayed), increased cytoplasmic density (5 ppm ethephon treatment) and alterations in the membrane structures (25 and 50 ppm ethephon treatments) were also observed.