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A smart design of hierarchical SAPO-5 acid catalyst using biomass derived monosaccharides as sustainable and low-cost mesoporogens has been developed. The hierarchical SAPO-5 was characterized by several physico-chemical techniques to elucidate structure-properties relationships and was tested as a catalyst in the MW-assisted glucose transformation in 5-HMF using γ-valerolactone (GVL) as green solvent.

The burning of crop residues is still a common, but heavily polluting, means of overcoming the problem of agricultural waste disposal. The main environmental damage comes from changes in soil properties (physical, chemical and biological), greenhouse gas emissions and decreasing crop yields. The use of crop residue biomass to replace fossil fuels is a valid alternative as it also supports farmers for land release and protects the environment. Many developing countries produce large quantities of agro-waste including rice husks, palm kernel shells, coconut shells, bagasse, milling residue-sawdust and plant biomass, such as grass. Residual biomass is a negative-cost feedstock for the production of fuels and commodity chemicals but could be used on a much larger scale. The realization of these economic benefits could provide the motivation necessary to achieve this goal and increase worldwide interest in biomass conversion for energy, fuels and chemicals. This chapter will describe some alternative uses for agricultural waste in Sub-Saharan Africa from bioenergy production to biomass conversion and briquetting.

A smart design of hierarchical SAPO-5 acid catalyst using biomass derived monosaccharides as sustainable and low-cost mesoporogens has been developed. The hierarchical SAPO-5 was characterized by several physico-chemical techniques to elucidate structure–properties relationships and was tested as a catalyst in the MW-assisted glucose transformation in 5-HMF using γ-valerolactone (GVL) as green solvent.

Lignin is the second most abundant polymer in lignocellulosic biomass. A biorefinery approach to lignin valorisation, as an alternative to the use of heating, can produce bioaromatics, and this idea is attracting ever more interest. However, the isolation of lignin for further processing is really quite challenging, making the valorisation of native lignin (i.e., lignin in raw biomass) crucially important. An analysis of vanillin yields in relation to total reaction feedstock weight shows that the economic viability of the process depends on the valorisation of all biomass components. This paper reports a microwave-assisted, catalyst-free aerobic oxidation process for biomass. The protocol yields bioaromatics (mainly vanillin and syringaldehyde, with traces of p-hydroxybenzaldehyde and acetovanillone) and organic acids (38.4 wt % maximum total yield) in only 30 min. Vanillin is the most valuable of the aromatic compounds to be produced by lignin oxidation, accounting for 8.7 wt % of the initial lignin. Th...

In the current study, fucoidans from brown alga Nizamuddinia zanardinii were isolated with conventional and non-conventional extraction procedures to evaluate the effects of recently introduced technologies on biochemical characteristics and saccharide composition of the extracts, along with their antibacterial, antiviral and cytotoxic properties. The results demonstrated that subcritical water extraction showed the highest fucoidans yield (13.15%), while the lowest yield was obtained using ultrasound extraction method (3.6%). The polysaccharide chains consisted of fucose, galactose, glucose, mannose and xylose, whose molar percentages differed according to the extraction method used. The weight mean average molecular weight of fucoidans varied between 444 and 1184 kDa. The FT-IR spectroscopy confirmed the presence of sulfate esters by bending vibration of C O S and stretching vibration of S O peaks at 818 and 1250 cm−1, respectively. Antibacterial assays showed that microwave- and subcritical water-extracted fucoidans inhibited the growth of E.coli and that enzyme-ultrasound, ultrasound-microwave and subcritical water extracted fucoidans exhibited inhibitory effects against P. aeruginosa at 2 mg/mL. Antiviral studies revealed that all the extracted fucoidans exerted strong antiviral activity against HSV-2 infection, with EC50 values in the 0.027–0.123 μg/mL range; indeed the viscozyme-extracted macromolecules displayed the best selectivity index.

A sulfated polysaccharide (fucoidan) has been isolated from Nizamuddinia zanardinii using subcritical water extraction method (SCWE), and extraction conditions were optimised using the response surface methodology. The optimum extraction conditions were found to be: extraction time of 29 min, extraction temperature of 150 °C, and raw material-to-water ratio of 21 g/mL. The fucoidan yield under these optimum conditions was 25.98%, which was considerably higher than that of conventional solvent extraction (5.2%). Extraction time and temperature were the extraction variables that most significantly affected fucoidan yield. Chemical and monosaccharide composition, molecular weight, and the antioxidant, anticancer and immunomodulatory activities of the extract have also been investigated. The monosaccharide composition of fucoidan included fucose (34.13%), mannose (30.70%), galactose (23.19%), xylose (9.35%) and glucose (2.65%). The average molecular weight of the extracted fucoidan was 694 kDa. Antioxidant results revealed that SCWE-extracted fucoidan had appreciable ABTS radical scavenging (70.35%) and reducing power (0.182 Abs). The anticancer activity of fucoidan ranged from 24.60 to 49.46% for HeLa cells and from 23.95 to 46.78% for HepG2 cells. The NO production of RAW264.7 cells was observed to be dose-dependent, while maximum NO production was found to be 34.82 μmol at a 50 μg/mL fucoidan concentration.

The ever-growing cocoa-product market has driven the cocoa industry to massive levels of production, thus causing excessive waste and by-product generation. Cocoa bean shells (CBS) and pod husks (CPH) are the main cocoa-industry by-products that possess substantial amounts of high added-value compounds. Polyphenols may be the most interesting compounds because of their widely known beneficial effects on human health. Over last decade, both science and industry have focused on finding new cost-effective technologies for phytochemical recovery that are able to lower extraction times, energy consumption and environmental impact. Ultrasound, microwave, pulsed electric field, and subcritical and supercritical fluid are some of these technologies. This review summarizes successful CBS and CPH polyphenol extraction processes that make use of the above-mentioned emerging methods. Moreover, the integration of novel business paradigms, in particular the circular economy and industry 4.0, can help sustainability to be achieved in the cocoa industry. Industrial relevance text Industrial cocoa by-products have become a massive burden since their inadequate disposal leads to a series of environmental issues. Value-added compounds recovery from CBS and CPH by means of enabling technologies assistance can lead to significant economic and environmental advantages. This approach, coherent with circular economy paradigm, can be integrated with a design of Industry 4.0 driving the development of new products and businesses.