Investigation of Australian olive mill waste for recovery of biophenols.
Olive mill waste is a potential source for the recovery of phytochemicals with a wide array of biological activities. Phytochemical screening of hexane, methanol, and water extracts revealed a diversity of compounds, perhaps overlooked in previous studies through intensive cleanup procedures. Methanol and water extracts contained large amounts of biophenols, and further testing of polar extraction solvents, including ethyl acetate, ethanol, propanol, acetone, acetonitrile, and water/methanol mixtures, highlighted the latter as the solvent of choice for extraction of the widest array of phenolic compounds. Stabilization of the resulting extract was best achieved by addition of 2% (w/w) sodium metabisulfite. Quantitative data are reported for nine biophenols extracted using 60% (v/v) methanol in water with 2% (w/w) sodium metabisulfite. Six compounds had recoveries of greater than 1 g/kg of freeze-dried waste: hydroxytyrosol glucoside, hydroxytyrosol, tyrosol, verbascoside, and a derivative of oleuropein.
Obied
Hassan K
HK
E.H. Graham Centre for Agricultural Innovation, School of Science and Technology, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
Allen
Malcolm S
MS
Bedgood
Danny R
DR
Prenzler
Paul D
PD
Robards
Kevin
K
D001315:Australia; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D007202:Indicators and Reagents; D007220:Industrial Waste / Q000032:analysis*; D008027:Light; D000069463:Olive Oil; D010636:Phenols / Q000032:analysis*; D010938:Plant Oils / Q000032:analysis*; D012015:Reference Standards; D013056:Spectrophotometry, Ultraviolet
D007202:Indicators and Reagents; D007220:Industrial Waste; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils