Mannosylerythritol lipids (MELs) are surface active compounds that belong to the glycolipid class of biosurfactants (BSs). MELs are produced by Pseudozyma sp. as a major component while Ustilago sp. produces them as a minor component. Although MELs have been known for over five decades, they recently regained attention due to their environmental compatibility, mild production conditions, structural diversity, self-assembling properties and versatile biochemical functions. In this review, the MEL producing microorganisms, the production conditions, their applications, their diverse structures and self-assembling properties are discussed. The biosynthetic pathways and the regulatory mechanisms involved in the production of MEL are also explained here.

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Accumulation of non-biodegradable plastics leads to increase in land and water pollution. Polyolefins including polyethylene and polypropylene are the major plastics to be dumped in the environment and due to their recalcitrant nature persist in the environment. The hydrophobicity, high molecular weight, chemical and structural composition of these polymers hinders their biodegradation. In this review current research that have been performed to understand the abiotic mechanism of the degradation process, and various physical, chemical and biochemical approaches that can be adopted to enhance their biodegradation are discussed. Genetic engineering approaches to enhance the performance of the microorganism or computational techniques to simulate the degradation pathways could be the future to speed up the degradation of these polymers.

The two most common commercial catalysts for the acylation of isobutylbenzene to produce the major ibuprofen intermediate 4-isobutylacetophenone are HF and AlCl 3 ; however, both of these catalysts suffer from significant drawbacks including the stringent safety issues associated with using volatile/toxic HF and the requirement for additional processing for deacidification of AlCl 3 . Here, two chloroaluminate-based catalysts, the ionic liquid (IL) [HN 222 ][Al 2 Cl 7 ] ([HN 222 ] = triethylammonium) and the liquid coordination complex (LCC, here an IL analog) AlCl 3 /O-NMPχ AlCl3 0.6 (O-NMP = N-methyl-2-pyrrolidone), were investigated and found to be efficient in the acylation of isobutylbenzene. Of the tested catalysts, the LCC, which along with neutral species has both a Lewis acidic cation ([AlCl 2 (O-NMP) 2 ] + ) and anion ([Al 2 Cl 7 ] − ), had the best catalytic performance (99% conversion with 96% selectivity).