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Mango is the second most consumed tropical fruit after banana and the by-products of mango processing (peel, kernel and seed) roughly comprise 35 -60% of the total fruit weight, thus representing a potentially high volume resource of exploitable biobased chemicals and materials. Herein, conversion and characterisation of waste mango peels from three different cultivars (Alphonso, Honey and Tommy Atkins) into pectin and porous cellulose using low temperature microwave-assisted acid-free hydrolytic conditions is reported. Microwave-assisted acid-free extraction yielded up to 11.63% (dry weight basis) of pectin which was characterised by IR, NMR (both solution and solid phase) and TGA which showed close similarity to commercial (acid extracted) pectin. The degree of esterification of pectin was determined by 13C NMR (75.6 -86.2%) and titrimetry (79.3-87.7%) and the pectin showed excellent gelling ability. The molecular weight as determined by GPC was in the range 14130 (Honey) -25540 (Tommy Atkins). Porosity measurements on the depectinated residue, i.e., residual cellulosic matter showed mesoporous characteristics: average pore diameter, 9.3 nm (Alphonso) -10.5 nm (Honey), however with poor surface area 16.3 m 2 g -1 (Honey) -26.0 m 2 g -1 . Interestingly, a second microwave hydrothermal treatment on these residues retained mesoporosity whilst significantly increasing surface area (88.8 m 2 g -1 (Honey) -124.0 m 2 g -1 (Alphonso)) and pore volume by approximately six-fold. This is the first detailed combined study of microwave-assisted extraction to yield pectin and mesoporous cellulose towards a potential zero waste mango biorefinery.

With crude oil reserves dwindling, the hunt for a sustainable alternative feedstock for fuels and materials for our society continues to expand. The biorefinery concept has enjoyed both a surge in popularity and also vocal opposition to the idea of diverting food-grade land and crops for this purpose. The idea of using the inevitable wastes arising from biomass processing, particularly farming and food production, is, therefore, gaining more attention as the feedstock for the biorefinery. For the three main components of biomass—carbohydrates, lipids, and proteins—there are long-established processes for using some of these by-products. However, the recent advances in chemical technologies are expanding both the feedstocks available for processing and the products that be obtained. Herein, this review presents some of the more recent developments in processing these molecules for green materials, as well as case studies that bring these technologies and materials together into final products for applied usage.

In this study, the preparation and characterization of biobased thermosets comprising epoxidized linseed oil (ELO), adipic acid and/or glutaric anhydride, initiated by N,N-4dimethylaminopyridine (DMAP) is reported. By changing the ratio of adipic acid to glutaric anhydride, the obtained resins changed from soft and flexible to hard and brittle materials. The Young's modulus varied from 25 MPa to 1477 MPa, tensile strength varied from 10.3 MPa to 25.7 MPa, and the elongation at break varied from 2.7% to 67.5%. The maximum toughness was found with the sample containing 20% glutaric anhydride and 80% adipic acid. With the increase of glutaric anhydride content, the total heat released during the curing reaction and the glass transition temperature (T g) increased. This is the first paper that reports the combination of glutaric anhydride and adipic acid as curing agents for epoxidized plant oils to produce thermosets ranging from flexible to hard.