Date palm (Phoenix dactylifera L.) pollen-based microgel and its promising medical and environmental applications

• The rigid structure of date palm pollen was converted into a gel-like matter. • The main factor in gel formation is the conversion of pectin-to-pectate. • The study provides a comprehensive characterization of pollen-derived microgel. • A sustainable, abundant resource was used for large-scale pollen-based production. • The pollen-based products were analyzed for medical and environmental applications. Pollen, a natural bi-layered porous microcapsule, plays a crucial role in plant reproduction by protecting the plant's genetic material. Due to its unique properties, it has garnered attention for medical and environmental applications. Recent studies have focused on transforming the pollen's rigid structure to soft, gel-like matter, enabling the creation of pollen-based products such as paper and sponge. The main factor in the gelation process involves pectin-to-pectate conversion within the pollen's inner layer. Previously, claimed that this transformation is restricted to eudicot plants, and some others, such as monocot plant pollens do not exhibit this gelation phenomenon. In this study, we successfully produced microgel from date palm ( Phoenix dactylifera L.) pollen (DPP), challenging this assertion. A significant portion of these monocot plant pollens exceeds the requirement of date production, presenting an opportunity for large-scale production without environmental concerns. Here, we have prepared pollen-based microgel, paper, and sponge and conducted a comprehensive analysis using various techniques such as optical and fluorescence microscopy, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), elemental CHN analysis, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric differential thermal analysis (TGA/DTA), rheological measurements, mechanical analysis, pH-sensitivity tests, swelling analysis, and oil absorption capacity. By discerning the specific physicochemical properties of these materials, we propose potential medical and environmental applications for further investigation.