title: Development of carotenoid storage cells in Bixa orellana L. seed arils.
abstract: The arils of Bixa orellana L. seeds contain carotenoid storage cells (CSCs). The main compounds in these cells include bixin and norbixin, which are important pigments in the food and pharmaceutical industries. Although many studies have been conducted on these chemical constituents, the cellular events that occur during the development of the carotenoid-accumulating cells in the arils and their relationship with the final carotenoid accumulation in the vacuoles remain unknown. In this study, the development of the CSCs in B. orellana arils was analyzed by light and transmission electron microscopy. Carotenoids formed in specialized cells, whose number and size increased during aril development. At various stages of development, the cytoplasm of the CSCs contained chromoplasts that held an extensive network of tubules and plastoglobules. Next to the chromoplasts, lipid droplets may fuse one another to form osmiophilic bodies. In addition, vesicles were observed next to the tonoplast. At the final stages of development, both the osmiophilic bodies and vesicles, which became quadrangular or rectangular, were stored in the vacuoles of the CSCs. This study reported for the first time the occurrence of different storage unit types within the vacuole of carotenoid storage cells.
authors: Laboratório de Ultraestrutura Vegetal, Departamento de Botânica, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS-Bloco A. Cidade Universitária, Av. Carlos Chagas Filho 373, 21949-490, Rio de Janeiro, RJ, Brazil. louro@biologia.ufrj.br.
authors: Ricardo P
authors: RP
authors: Louro
authors: Laboratório de Biodiversidade e Biotecnologia, Departamento de Botânica, Instituto de Biociências, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Av. Pasteur 458, S. 301, Urca, Rio de Janeiro, RJ, Brazil, 22290-240.
authors: Laura J M
authors: LJ
authors: Santiago
mesh_terms: D031212:Bixaceae / Q000166:cytology / Q000196:embryology* / Q000648:ultrastructure; D002338:Carotenoids / Q000378:metabolism*; D018548:Cotyledon / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D005638:Fruit / Q000166:cytology / Q000254:growth & development / Q000648:ultrastructure; D059828:Plant Cells / Q000378:metabolism* / Q000648:ultrastructure; D012639:Seeds / Q000166:cytology / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D002338:Carotenoids
keywords: Achiote; Annatto; Bixa orellana; Bixin; Carotenoid; Chromoplast; Urucum