Faculty of Food Technology and Biotechnology, University of Zagreb
Abstract
In the present work, the production of two potent antioxidants, gallic and ellagic acids, has been studied using solid-state fermentation (SSF) of tannin-rich aqueous plant extracts impregnated in polyurethane foam. Extracts from creosote and tar bush were ino-culated with Aspergillus niger PSH spores and impregnated in the polyurethane support.The kinetics of the fermentation was monitored every 24 h. The maximum biodegradation of hydrolysable and condensed tannins was, respectively, 16 and 42 % in creosote bush, and 40 and 83 % in tar bush. The maximal productions of gallic and ellagic acid (152 and177 %, respectively) were reached with aqueous extracts of creosote bush. Tar bush extracts inoculated with A. niger PSH spores produced only gallic acid (92 %), while ellagic acid was not recovered after the fermentation process. Results demonstrated the potential use of these plants as a source for the production of antioxidants.U ovom je radu istražena proizvodnja dvaju jakih antioksidanasa, galne i elagične kiseline, na čvrstoj podlozi taninom bogatih ekstrakata impregniranih poliuretanskom pjenom. Ekstrakti biljaka Larrea tridentata i Fluorensia cernua inokulirani su sporama plijesni Aspergillus niger PSH i zatim impregnirani poliuretanskom pjenom. Kinetika procesa praćena je svakih 24 sata. Maksimalna biorazgradnja hidroliziranih tanina iznosila je 16 % u ekstraktu biljke L. tridentata i 40 % u ekstraktu biljke F. cernua, dok je maksimalna biorazgradnja kondenziranih tanina bila 42 i 83 %. Maksimalna proizvodnja galne (152 %) i elagične kiseline (177 %) postignuta je primjenom vodenog ekstrakta biljke L. tridentata. Uporabom ekstrakta biljke F. cernua, inokuliranog sporama A. niger PSH, proizvedena je samo galna kiselina (92 %), dok prisutnost elagične kiseline nije utvrđena nakon završetka procesa. Rezultati dokazuju da se te dvije biljke mogu upotrijebiti za proizvodnju antioksidanasa
