Clusia : cultura de tecidos e importancia do seu latex na sobrevivencia das especies

AUTOR(ES)
DATA DE PUBLICAÇÃO

2001

RESUMO

Focusing on the latex importance for the Clusia species survival we have investigated the chemical composition of 14 clusia látex, belonging to 4 different taxonomic sections (1- Chlamydoclusia: C. nemorosa, C. rosea, C. grandiflora; 2- Criuva: C. criuva, C. parviflora; 3- Phloianthera: C. hilariana, C. lanceolata 4- Cordylandra: C. fluminensis, C. paralicola, C. weddelliana, C. panapanari, C. spiritu-sanctensis) and two hybrids (C. paralicola X C. weddeliana e C. lanceolata e C. nemorosa). Biautography tests revealed that polar componentes possessed antibacterial and antifungal activity while latex produced by hybrid plants were less active against microorganisms (bacteria: Escherichia coli CCT 5050; Bacillus subtilis CCT 0089; Rhodococcus equi CCT 0541; Staphylococcus aureus CCT 4259; Micrococus luteus CCT 2720; Salmonella typhymurium CCT 0528, e fungi: Aspergillus fumigatus CCT 01277; Aspergillus niger CCT1435; Fusarium oxysporum CCT 3244; Rhizopus oryzae CCT 4964; Alternaria alternata CCT 1250; Cladosporium cladosporioides CCT5039 e Candida albicans CCT 0776). The chemical composition was rather similar in all investigated species: 30% of the solids in the latex suspension was composed by a polysaccharide possessing arabinose (29.82 a 59.15%), rhamnose (4.81 to 9.75%), manose (7.44 to 12.65%), galactose (26.27 to 44.24 %) and glucuronic acid (2.07 to 4.24%). C NMR analysis revealed that the main chain is made of (13) b-galactose units and branching of b-galactose (16). Sesquiterpenes, triterpenes and phenolic dervivatives were the main constituents of the methanol soluble fraction Traces of poliisoprenylated benzophenones were detected in C. paralicola, C. parviflora and C. hilariana latex. GC/MS and C NMR analyses were used to identify the components of triterpene mixtures (b-amirine, eufane, lanostane) present in the latex. Some metabolites were isolated and fully characterized as olean-12-en-3-oxo-28-oic acid and 3 tocoferol derivatives, of these 2 tocopherol derivatives were never mentioned in the genus and one is new. The b-amirine, lupeol, lupenone, and friedelanone were major constituents of the epicuticular waxes of C. lanceolata, C. nemorosa, C. paralicola, C. paralicola x C. nemorosa e C. lanceolata x C. nemorosa but it was rather difficult to establish a correlation between the chemical composition of the hybrids and natural species and their resistance to microorganism attack and herbivory. In order to understand microorganism attack and látex composition, 4 microorganisms were isolated from sick hybrid specimen but none of them were pathogenic. Finally, composition of in vitro Clusia cell cultures was obtained by GC/MS of the caluses revealing the presence of olean-12-en-3-oxo-28-oic acid and olean-12-en-3-hydroxy-28-oic acid, which were also detected in the latex of C. grandiflora. All the above mentioned analysis do not allow definite conclusion on the role of the latex in the plant protection but they have certainly contributed to the elucidate the chemical composition of Clusia latex, epicuticular waxes and cell cultures which was never performed before. Finally the Clusia in vitro cell culture protocol was successful and the metabolites were related to those present in vivo.

ASSUNTO(S)

latex tecidos (anatomia e fisiologia) - cultura e meios de cultura

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