Luísa B. Roseiro

Production and purification of xylooligosaccharides from oil palm empty fruit bunch fibre by a non-isothermal process

Oil palm empty fruit bunches (OPEFB) fibre, a by-product generated from non-woody, tropical perennial oil palm crop was evaluated for xylooligosaccharides (XOS) production. Samples of OPEFB fibre were subjected to non-isothermal autohydrolysis treatment using a temperature range from 150 to 220 °C. The highest XOS concentration, 17.6g/L which relayed from solubilisation of 63 g/100 g xylan was achieved at 210 °C and there was a minimum amount of xylose and furfural being produced. The chromatographic purification which was undertaken to purify the oligosaccharide-rich liquor resulted in a product with 74-78% purity, of which 83-85% was XOS with degree of polymerisation (DP) between 5 and 40.

Milk oligosaccharides: a review

Milk oligosaccharides (OSs) confer unique health benefits to the neonate. Although human digestive enzymes cannot degrade these sugars, they support specific commensal microbes and act as decoys to prevent the adhesion of pathogenic micro-organisms to gastrointestinal cells. The limited availability of human milk oligosaccharides (HMOs) impedes research into these molecules and their potential applications in functional food formulations. Recent studies show that complex OSs with fucose and N-acetyl neuraminic acid (key structural elements of HMO bioactivity) also exist in caprine milk, suggesting a potential source of bioactive milk OSs suitable as a functional food ingredient.

In vitro evaluation of the fermentation properties and potential prebiotic activity of caprine cheese whey oligosaccharides in batch culture systems

The prebiotic effect of oligosaccharides recovered and purified from caprine whey, was evaluated by in vitro fermentation under anaerobic conditions using batch cultures at 37°C with human faeces. Effects on key gut bacterial groups were monitored over 24 h by fluorescence in situ hybridization (FISH), which was used to determine a quantitative prebiotic index score. Production of short-chain fatty acids (SCFAs) as fermentation end products was analyzed by high-performance liquid chromatography (HPLC). Growth of Bifidobacterium spp was significantly higher (P ≥ 0.05) with the purified oligosaccharides compared to the negative control. Lactic and propionic acids were the main SCFAs produced. Antimicrobial activity of the oligosaccharides was also tested, revealing no inhibition though a decrease in Staphylococcus aureus and Escherichia coli growth. These findings indicate that naturally extracted oligosaccharides from caprine whey could be used as new and valuable source of prebiotics.

CHAPTER 5:Relevance of Ionic Liquids and Biomass Feedstocks for Biomolecule Extraction

Environmentally benign methods of value-added product extraction from biomass feedstock can drive greater independence from fossil resources and definitively assure a more sustainable future for the next generations. Thus, the maximal valorization of abundant feedstock, such as residues from agricultural and food industries, for example, contributes positively to the development of bio-based economies. This chapter presents an overview of the advances related with the utilization of ionic liquids with different biomass materials, namely by-products and co-products of the agricultural and food industries, to tackle the treatment of inherently low-value raw materials into value-added products. In this chapter, attention is paid to the type of ionic liquid used, the variety of biomass feedstocks and the combined use of ionic liquids with temperature and with different pre-treatment techniques. Selected examples illustrate the applicability of ionic liquids for obtaining bioactive phytomolecules that can be used in the biomedical, pharmaceutical, environmental and food industries.