Date palm (Phoenix dactylifera L.) is one of the world’s oldest cultivated plants. Post-harvest losses of date palm due to fungal contamination reached up to 50% of the total production. This study aimed to investigate the potential of the extract of Tasmanian pepper leaf (TPL) and the non-thermal treatment of photosensitization mediated by curcumin in reducing the fungal contamination and enhancing the shelf life of date palm. In the in vivo storage study, the dates were treated with three different concentrations of TPL extract 12.5, 25, and 50 µg/mL and stored at 30 °C. The findings obtained for the treatment with TPL extract exhibited potent antifungal activity against most of the tested fungi, where minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were < 25 µg/mL for polygodial, the bioactive compound in TPL. The shelf life of date palm treated by 50 µg/mL polygodial was extended up to 21 days, thrice as much as the untreated controls. In contrast, a lower concentration of TPL extract (25 µg/mL polygodial) revealed up to a 15-day shelf life extension compared to untreated dates (7 days). The results obtained from the study suggested that using TPL extracts against pathogenic and spoilage fungi occurring in fresh date fruits is a promising treatment for the shelf life extension of fresh date fruits at room temperature.
Keywords: Date fruit; Phoenix dactylifera; Tasmanian pepper; Tasmannia lanceolata; fungi; polygodial; post-harvest; shelf life; spoilage.