Different Carotenoid Enrichment in Two Climacteric Fruits after Post- Harvest UV-B Treatment

Background: Ultraviolet B (UV-B) radiation is a promising and environmentally friendly technique, which in a low flow rate, can induce bioactive compound synthesis. This work aimed at evaluating the effectiveness of post-harvest UV-B treatment in order to improve carotenoid content in climacteric fruits like persimmon and guava fruits. Methods: The fruits were harvested at commercial maturity and placed into climatic chambers equipped with UV-B lamps. For control treatment, the UV-B lamps were covered by a benzophenone film, known to block the radiation. This radiation was applied during 48 hours and fruits were sampled at 25, 30 and 48 hours of each treatment. HPLC analysis was performed to separate and identify carotenoid compounds from fruit skin after a saponification process. Results: Fruit from 30 hours treatment began to present a carotenoid accumulation since the majority of analyzed compounds exhibited its synthesis stimulated from this time on. In persimmon skin, it was observed that the maximum content was reached after 48 hours of UV-B treatment. Conclusion: These results suggest that this post-harvest UV-B treatment can be an innovative and a viable method to induce beneficial effects on guava and mainly on persimmon fruit.