Prebiotics are short chain carbohydrates that are non-digestible by digestive enzymes in humans and selectively enhance the activity of some groups of beneficial bacteria. In the intestine, prebiotics are fermented by beneficial bacteria to produce short chain fatty acids. Prebiotics also render many other health benefits in the large intestine such as reduction of cancer risk and increase calcium and magnesium absorption. Prebiotics are found in several vegetables and fruits and are considered functional food components which present significant technological advantages. Their addition improves sensory characteristics such as taste and texture, and enhances the stability of foams, emulsions and mouthfeel in a large range of food applications like dairy products and bread. This contribution reviews bioactives from food sources with prebiotic properties. Additionally, food application of bioactive prebiotics, stimulation of the viability of probiotics, health benefits, epidemiological studies, and safety concerns of prebiotics are also reviewed.

a b s t r a c tThe optimum extraction conditions for highest recovery of total phenolics content (TPC) and antioxidant capacities (AC) were analysed for Mangifera pajang peels (MPP), using response surface methodology. The effects of ethanol concentration (X 1 : 20-80%), extraction temperature (X 2 : 30-65°C) and liquid-to-solid ratio (X 3 : 20-50 mL/g) on the recovery of total phenolics (Y 1 ) and antioxidant capacity (Y 2 ) were investigated. A second order polynomial model produced a satisfactory fitting of the experimental data with regard to total phenolic content (R 2 = 0.9966, p < 0.0001) and antioxidant capacity (R 2 = 0.9953, p < 0.0001). The optimum extraction conditions for TPC were 68%, 55°C and 32.7 mL/g, and for AC were 68%, 56°C and 31.8 mL/g, respectively. Predicted values for extraction of TPC and AC agreed well with the experimental values. Liquid chromatography-mass spectrometry of the optimally obtained extracts from MPP revealed the major phytochemicals as mangiferin, gallic acid, catechin and epicatechin.

a b s t r a c tThe composition of bambangan peel dietary fibre (DF) and several properties related to its nutritional quality were investigated. The physicochemical properties and antioxidant capacity for the fibre-rich powder (FRP) were investigated, and the chemical composition for soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) were also studied. The FRP had a high amount of total dietary fibre (TDF; 72.3 g/ 100 g FRP) with a balanced SDF/IDF ratio (46.3/53.7%). The FRP had a high glucose retardation index, water-holding capacity (WHC), oil-holding capacity (OHC), and swelling. The antioxidant capacity of the FRP, as determined by the DPPH Å assay using an Elisa reader, exhibited a strong potency due to the presence of associated total polyphenols (98.3 mg/g FRP). These FRP characteristics indicated that bambangan peels are a rich source of DF, antioxidants, and other bioactive compounds that can be incorporated with food products to improve the nutraceutical properties of these products.