The influence of nitrogen and phosphorus fertilization on production of biomass and mucilage in C... more The influence of nitrogen and phosphorus fertilization on production of biomass and mucilage in Cissus sicyoides plants was evaluated. 45-day old plants obtained from cuttings were planted in pots with capacity for 5 Kg of soil, having as substrate allic cambisol soil, medium texture from Nazareno (Brazil). Basic fertilization with macro and micronutrients was done. Nitrogen doses (0; 40; 80; 160 and 200 mg of N/Kg of soil) and phosphorus doses (50 and 150 mg of P/Kg of soil) were evaluated. The experiment was laid out in a complete randomised factorial scheme of 5 x 2, with four replications. The research was carried out in a greenhouse during 90 days, being evaluated the dry matter of leaves, stalks and roots; chemicals characteristics and mucilage were determined. Between nitrogen and phosphorus doses and the production of dry matter of leaves was observed interaction. Higher biomass gain occurred with higher nitrogen dose of 150 mg P/Kg of soil. The mucilage production increased...
Pilocarpine is an alkaloid obtained from the leaves of Pilocarpus genus, with important pharmaceu... more Pilocarpine is an alkaloid obtained from the leaves of Pilocarpus genus, with important pharmaceutical applications. Previous reports have investigated the production of pilocarpine by Pilocarpus microphyllus cell cultures and tried to establish the alkaloid biosynthetic route. However, the site of pilocarpine accumulation inside of the cell and its exchange to the medium culture is still unknown. Therefore, the aim of this study was to determine the intracellular accumulation of pilocarpine and characterise its transport across membranes in cell suspension cultures of P. microphyllus. Histochemical analysis and toxicity assays indicated that pilocarpine is most likely stored in the vacuoles probably to avoid cell toxicity. Assays with exogenous pilocarpine supplementation to the culture medium showed that the alkaloid is promptly uptaken but it is rapidly metabolised. Treatment with specific ABC protein transporter inhibitors and substances that disturb the activity of secondary active transporters suppressed pilocarpine uptake and release suggesting that both proteins may participate in the traffic of pilocarpine to inside and outside of the cells. As bafilomicin A1, a specific V-type ATPase inhibitor, had little effect and NH4Cl (induces membrane proton gradient dissipation) had moderate effect, while cyclosporin A and nifedipine (ABC proteins inhibitors) strongly inhibited the transport of pilocarpine, it is believed that ABC proteins play a major role in the alkaloid transport across membranes but it is not the exclusive one. Kinetic studies supported these results.
The influence of nitrogen and phosphorus fertilization on production of biomass and mucilage in C... more The influence of nitrogen and phosphorus fertilization on production of biomass and mucilage in Cissus sicyoides plants was evaluated. 45-day old plants obtained from cuttings were planted in pots with capacity for 5 Kg of soil, having as substrate allic cambisol soil, medium texture from Nazareno (Brazil). Basic fertilization with macro and micronutrients was done. Nitrogen doses (0; 40; 80; 160 and 200 mg of N/Kg of soil) and phosphorus doses (50 and 150 mg of P/Kg of soil) were evaluated. The experiment was laid out in a complete randomised factorial scheme of 5 x 2, with four replications. The research was carried out in a greenhouse during 90 days, being evaluated the dry matter of leaves, stalks and roots; chemicals characteristics and mucilage were determined. Between nitrogen and phosphorus doses and the production of dry matter of leaves was observed interaction. Higher biomass gain occurred with higher nitrogen dose of 150 mg P/Kg of soil. The mucilage production increased...
Pilocarpine is an alkaloid obtained from the leaves of Pilocarpus genus, with important pharmaceu... more Pilocarpine is an alkaloid obtained from the leaves of Pilocarpus genus, with important pharmaceutical applications. Previous reports have investigated the production of pilocarpine by Pilocarpus microphyllus cell cultures and tried to establish the alkaloid biosynthetic route. However, the site of pilocarpine accumulation inside of the cell and its exchange to the medium culture is still unknown. Therefore, the aim of this study was to determine the intracellular accumulation of pilocarpine and characterise its transport across membranes in cell suspension cultures of P. microphyllus. Histochemical analysis and toxicity assays indicated that pilocarpine is most likely stored in the vacuoles probably to avoid cell toxicity. Assays with exogenous pilocarpine supplementation to the culture medium showed that the alkaloid is promptly uptaken but it is rapidly metabolised. Treatment with specific ABC protein transporter inhibitors and substances that disturb the activity of secondary active transporters suppressed pilocarpine uptake and release suggesting that both proteins may participate in the traffic of pilocarpine to inside and outside of the cells. As bafilomicin A1, a specific V-type ATPase inhibitor, had little effect and NH4Cl (induces membrane proton gradient dissipation) had moderate effect, while cyclosporin A and nifedipine (ABC proteins inhibitors) strongly inhibited the transport of pilocarpine, it is believed that ABC proteins play a major role in the alkaloid transport across membranes but it is not the exclusive one. Kinetic studies supported these results.
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