Tail-group unsaturation tailors the surface and self-assembly behavior of C18-fatty acid-based glycolipids

•Head group size and acyl chain unsaturation influence the interfacial adsorption.•Glycolipids with unsaturated acyl chains furnished better surface activity.•Monounsaturated lipid tail provided more nonpolar micellar core.•Unsaturation degree is a key factor for drug encapsulation and cumulative release. Biosurfactants cover a wide variety of application in diverse fields as interfacial modifiers and drug delivery carriers. Narrow molecular diversity of biosurfactants especially limits their potential application. Herein, we synthesized eight bio-based glycolipids to ascertain the structure–property relationship via changing unsaturation degree of hydrophobic chain and polar glucosidic moiety. The surface parameters of these glycolipids are evaluated with surface tension (ST) and Langmuir Blodgett (LB) studies. The surface-active properties including foaming, wetting, emulsifying, and solubilizing studies were performed to derive the impact of unsaturation degree. Self-assembly properties including critical micelle concentration (CMC), micropolarity, microviscosity, aggregation number (Nagg), and size have been employed to explore impact of unsaturation degree. Studies on encapsulation and enzymatic release of hydrophobic bioactive (curcumin) from glycolipid self-assemblies revealed them as nano-carriers. Interestingly, glycolipids with oleyl chain exhibited excellent hydrophobic encapsulation capacity and release rates are depending on degree of unsaturation and size of headgroup. Results suggest that configuration of unsaturated tail can be tuned to manipulate the interfacial properties and encapsulation-release profile of hydrophobic bioactive.