Towards biorefinery: Exploring the potential of seaweed-derived biodiesel and its residual biomass in improving the traits of Eruca vesicaria (L.) Cav.
Rania A. El‐Shenody, Mostafa E. Elshobary, Gehad A. Ragab, Shuhao Huo, Dorya I. Essa
Abstract
Total lipids levels and fatty acid composition of the marine macroalgae Laurencia “obtuse” (Hudson) J. V. Lamouroux (Rhodophyceae), Cystoseira tamariscifolia (Hudson) Papenfuss (Phaeophyceae) and Ulva compressa (Chlorophyceae) collected from the coastal area of Marsa Matruh, Egypt were evaluated for their biodiesel potential. Seawater parameters were measured. Ulva compressa recorded the highest total lipid content (57.52 mg/g DW), followed by C. tamariscifolia, “and L. obtuse was the lowest.” The fatty acid methyl ester profiles were analyzed by gas chromatography. The assessment of the biodiesel properties of the fatty acid methyl ester (FAME) of the three seaweed species was convenient with the European (EN 14214) and American (ASTM D6751-02) biodiesel standards. The mineral composition of the collected defatted residual seaweed biomass (DRSB) of the three seaweeds showed various macro- and microelements, including K, Ca, Mg and Fe. Applying aqueous DRSB extract as a foliar spray and/ or seed priming significantly enhanced growth criteria and photosynthetic pigments of 30-days old E. vesicaria plants. The mineral contents of the shoots were significantly elevated by DRSB extract foliar spray treatment compared to the non-treated control. Spraying with DRSB extract exhibited the most remarkable increase in total phenolics, flavonoids, and antioxidant activity. Therefore, foliar spray application with DRSB extract was highly effective and favored over priming as a simple biostimulant that enhanced E. vesicaria growth and nutritional value.