Influence of Storage and Processing on Citrus Ribonucleotides

Changes in nucleotides and ribonucleic acids (RNA) in 'Valencia' orange have been determined as influenced by storage, ethylene, heat and commercial concentrating practices. All treatments tended to lower polymeric RNA species. Patterns of interactions in the case of nucleotides were evident and distinct for certain treatments. Changes in nucleotides may be related to the quality of the processed citrus products. Acid-soluble nucleotides and polymeric RNA have been isolated and identified from citrus fruits (1, 2, 10) as well as other fruits and vegetables (2, 3, 9, 12). Nucleotides are essential intermediates for metabolism and in some cases have regulatory functions (5). In citrus products, they may play a role in modifying flavor and stabilizing juice cloud (10). and nucleotides absorbed onto activated charcoal. Nucleotides were eluted from the charcoal with ahotethanol: H2O: NH40H (50:49:1 v/v) solu tion, after which the filtrate was reduced to a small volume under vacuum. Separation of the nucleotides from the extract was accomplished using anion-exchange chromatography on a Dowex 1x8 resin. The effluent, 1 ml/min., was monitored at 260 nm using a Beckman, model DU,