Glicoalcalóides presentes em batatas (Solanum tuberosum L): uma abordagem atual / Glycoalkaloids in potatoes (Solanum tuberosum L): an overview

A batata (Solanum tuberosum L.) é um dos mais importantes alimentos na dieta humana em decorrência de sua disponibilidade e características nutricionais. Entretanto, membros da família Solanaceae têm como características, durante crescimento e após colheita, a produção de compostos potencialmente tóxicos denominados glicialcalóides. Os princaipais glicoalcalóides presentes em batatas são a-solanina e a-chaconina, e estes correspondem a 95 pór cento ou mais dos glicoalcalóides totais. Estes compostos parecem ter duas ações tóxicas no organismo humano: uma sobre a acetilcolinesterase e outra sobre o trato gastrintestinal. A concentração máxima desses compostos considerada segura para consumo humano é estimada em 200mg/kg de batata in natura, expressa como glicoalcalóides totais. O presente artigo faz uma ocorrência e métodos de análise

In vitro procuction of scopolamine and hyoscyamine: influence of different elicitors on hairy root cultures of Brugmansia candida

The tropane alkaloids scopolamine and hyoscyamine arestill extracted from plants that belong to several species of Solanaceae because their chemical syntesis is difficult and expensive. These anticholinergic agents are employed in medicine as antispasmodics, preoperative medication and for the treatment of motion sickness. In our laboratory, hairy roots of Brugmansia candida, a South American plant which both alkaloids, were obtained through transformation with Agrobacterium rhizogenes and cultured in vitro. To increase the productivity of the cultures, these were exposed to different elicitors: CaCl2, salicylic acid and autoclaved roots of B. candida. The effects on growth, alkaloid accumulation and release into the medium were evaluated. CaCl2 at 50.00 and 100.00 mM, increased the accumulation of scopolamine and hyoscyamine after 24 hours ( 30-60per cent), while after 48 hour levels of 50.00 mM decreased their accumulation ( 50per cent). No effect was observed on release of alkaloids into the medium. Salicylic acid, a compound involved in plant defense, at 0.01 and 1.00 mM increased accumulation of booth alkaloids (ranging from 30 to 170 per cent), particularly after 24 and 48 hours. There was also increase in the release of scopolamine and hyoscyamine into the medium. The homogenized roots had a positive effect on alkaloid accumulation in the roots throughout the experiment (ranging from 100 to 500 per cent). This was most noticeable for hyoscyamine, particulary after 24 and 72 hours of exposition. The results seen with homogenized roots are probably due to endogenous elicitors which are liberated in the subsequent steps of autoclaving and sonication.

phytochemical screening of some solanaceous plants phytosterol and fatty acid constituents of solanum elaeagnifolium and solanum nigrum in addition to pharmacological and antimicrobial investigation.

The phytochemical screening of 19 Solanaceous plant samples were performed. Alkaloids were detected in 13 samples, flavonoids in 6 samples, phytosterols, terpenoids were detected in 11 and 7 samples while, tannins only in 2 samples. The phytosterol and fatty acid constituents in the lipids contents of Solanum elaeagnifolium and Solanum nigrum were determined by GLC. Sqalene, stigmasterol and beta-sitosterol are the main constituents in the plant samples besides campasterol in the seeds and stems of S. elaeagnifolium. Palmitic and palmitoleic acids are the main constituents in both plant species beside stearic and linoleic acids in the seeds of S. nigrum. All the examined extracts of both S. elaeagnifolium and S. nigrum induced a minimal stimulatory effect when tested on isolated rabbit jejunum and moderate relaxant effect of both rate and amplitude on isolated heart. The antimicrobial activity of the examined extracts of the both plants shows activity against B. subtilis and higher activity against E. coli and S. aureus

Solasodine levels in Solanum sisymbriifolium Lam.

Solasodine content in berries, leaves and stem of S. sisymbriifolium, using three different procedures, was 0.93, 0.73 and 0.23% respectively. Further in chromatogram not only solasodine but three more alkaloids (Rf 0.22, 0.48 and 0.88) were found which could not be identified due to lack of authentic samples.