The artichoke processing industry generates large amounts of wastes and residues (up to 60% of harvested vegetal) the management of which creates serious problems of environmental impact. These by-products represent an interesting source of phenolic compounds with different biological and pharmaceutical properties. The results of different clinical investigations have widely demonstrated the health-protective potential of artichoke extracts in terms of hepatoprotective, anticarcinogenic and hypocholesterolemic activity. Phenolic compounds, including mono- and di-isomers of caffeoylquinic acids (chlorogenic acid and cynarin) and flavonoid O-glycosides (luteolin and apigenin derivatives) have been identified as the main responsible compounds for the biological properties of artichoke extracts. Membrane technology for concentrating and/or purifying bioactive phenolic compounds from different vegetable sources offers several advantages (low temperature, absence of phase transition and low energy consumption) when compared with conventional technologies. In this work, an integrated membrane process was developed on laboratory scale to fractionate and purify phenolic compounds from artichoke wastewaters. In particular, a two-step nanofiltration (NF) process was investigated in order to produce a retentate fraction enriched in phenolic compounds after a preliminary ultrafiltration (UF) of an aqueous artichoke extract devoted to the removal of suspended solids. NF membranes in spiral-wound configuration (NP030 from Microdyn Nadir and Desal DL from GE Water & Process Technologies) were selected in order to separate phenolic compounds from sugars. For both NF membranes the effect of transmembrane pressure (TMP) on the rejection of compounds of interest was investigated. The performance of selected membranes was also evaluated in terms of permeate flux, fouling index and water permeability recovery. Permeate and retentate fractions were analyzed in terms of total content of polyphenols, sugars, low molecular weight phenolic compounds and antioxidant activity. The experimental results indicated the possibility to produce a fractionated extract of high biological value to be used for nutraceuticals or dietary supplements and a purified stream with good characteristics for irrigation or for recycling.
Recovery of phenolic compounds from artichoke wastewaters by integrated membrane process
C Conidi;A Cassano;
2014
Abstract
The artichoke processing industry generates large amounts of wastes and residues (up to 60% of harvested vegetal) the management of which creates serious problems of environmental impact. These by-products represent an interesting source of phenolic compounds with different biological and pharmaceutical properties. The results of different clinical investigations have widely demonstrated the health-protective potential of artichoke extracts in terms of hepatoprotective, anticarcinogenic and hypocholesterolemic activity. Phenolic compounds, including mono- and di-isomers of caffeoylquinic acids (chlorogenic acid and cynarin) and flavonoid O-glycosides (luteolin and apigenin derivatives) have been identified as the main responsible compounds for the biological properties of artichoke extracts. Membrane technology for concentrating and/or purifying bioactive phenolic compounds from different vegetable sources offers several advantages (low temperature, absence of phase transition and low energy consumption) when compared with conventional technologies. In this work, an integrated membrane process was developed on laboratory scale to fractionate and purify phenolic compounds from artichoke wastewaters. In particular, a two-step nanofiltration (NF) process was investigated in order to produce a retentate fraction enriched in phenolic compounds after a preliminary ultrafiltration (UF) of an aqueous artichoke extract devoted to the removal of suspended solids. NF membranes in spiral-wound configuration (NP030 from Microdyn Nadir and Desal DL from GE Water & Process Technologies) were selected in order to separate phenolic compounds from sugars. For both NF membranes the effect of transmembrane pressure (TMP) on the rejection of compounds of interest was investigated. The performance of selected membranes was also evaluated in terms of permeate flux, fouling index and water permeability recovery. Permeate and retentate fractions were analyzed in terms of total content of polyphenols, sugars, low molecular weight phenolic compounds and antioxidant activity. The experimental results indicated the possibility to produce a fractionated extract of high biological value to be used for nutraceuticals or dietary supplements and a purified stream with good characteristics for irrigation or for recycling.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
