Recovery of phenolic compounds from Eucalyptus wood wastes using ethanol-salt-based aqueous two-phase systems

Abstract

In this work the partition behavior of phenols using ethanol-salt-based aqueous two phase systems (ATPS) was evaluated. The aim was the recovery of phenolic compounds with antioxidant capacity from eucalyptus wood industrial wastes. Experiments were planned to study the influence of several parameters on phenols partition, including type of inorganic salt (ammonium sulphate, a mixture of monopotassium phosphate and potassium diphosphate and potassium diphosphate), tie-lie lenght (TLL), volume ratio (V r ), settlement time and temperature. Phenols could be recovered preferently from the top or bottom phases depending on the salt used. It was demostrated that tie-lie lenght, volume ratio and temperature had influence on phenols partition. The highest total phenols yield 5,36 mg gallic acid equivalent (100 mg oven dried wood) -1 and FRAP antioxidant activity, 20 mmol AAE (100 g oven dried wood) -1 , was obtained using ATPS formed by 40.6% (w/w) ethanol and 12% (w/w) of ammonium sulphate at 65ºC. Analysis of the extract by RP-HPLC-ESI-TOF confirmed the presence of the phenolic compounds with potential antioxidant activity, namely, ellagic acid, myricetin 3-O-rhamnoside and quercetin 3-glucoside.

Chemical Composition of Pyroligneous Acid Obtained from Eucalyptus GG100 Clone

“…Further research should be carried out to isolate and specifically test the mutagenic character of crude GG100 PA and its phenolic fraction. Effective methods to isolate the phenolic fraction from PA are reported in the literature [ 29 , 39 ].…”

Optimized and Scalable Green Extraction of Pristimerin, an Anticancerigen from Mortonia greggii, by Ethanol–Phosphate Aqueous Two-Phase Systems

“…Besides, V R values below 1 have demonstrated to improve the extraction yield of anthocyanins from mulberry . In addition to these results, increasing TLL values enhanced the extraction of bioactive compounds in carrots using an ethanol–phosphate ATPS; and higher TLL in combination with lower V R values displayed better yields and purity for phenolic compounds in eucalyptus using the previously mentioned ATPS …”

“…26 In addition to these results, increasing TLL values enhanced the extraction of bioactive compounds in carrots using an ethanol−phosphate ATPS; 27 and higher TLL in combination with lower V R values displayed better yields and purity for phenolic compounds in eucalyptus using the previously mentioned ATPS. 20 In our experimental procedure, two conditions showed high yield and purity values: TLL 70% (w/w) with V R 3 and 0.33. Therefore, a single condition was selected in which a higher purity was preferred over yield, sacrificing this last value slightly.…”

“…19 Also, the extraction of phenolic compounds from Eucalyptus wood wastes with an ethanol−ammonium sulfate system has been maximized. 20 Contrastingly, the recovery of crocin from saffron stigmas through the same type of ATPS has been evaluated, and the results did not exhibit significant differences in the obtained recovery yields. 21 To industrially transfer a technological ATPS-based process for pristimerin extraction from Mortonia greggii root bark, green and scalable bioprocesses that consider all optimizable variables need to be established.…”

“…As an example, extraction yields for fucoxanthin from Isochrysis galbana and Phaeodactylum tricornutum with ethanol–phosphate systems have been optimized . Also, the extraction of phenolic compounds from Eucalyptus wood wastes with an ethanol–ammonium sulfate system has been maximized . Contrastingly, the recovery of crocin from saffron stigmas through the same type of ATPS has been evaluated, and the results did not exhibit significant differences in the obtained recovery yields …”