Naslov
APLICATION OF ULTRASOUND-ASSISTED EXTRACTION FOR THE ISOLATION OF TYROSOL, HYDROXITYROSOL AND OLEUROPEIN FROM OLIVE POMACE

Autori
Albahari, Petra ; Jug, Mario ; Brnčić, Mladen ; Vitali Čepo, Dubravka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
WITH FOOD TO HEALTH, Book of abstract and papers of 8th International symposium / Šubarić, D ; Jašić M. - Tuzla : Farmacutski fakultet Univerziteta u Tuzli, 2015, 41-41

Skup
WITH FOOD TO HEALTH, 8th International symposium

Mjesto i datum
Tuzla, Bosna i Hercegovina, 15.10.2015. - 17.10.2015

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
ultrasound-assisted extraction ; olive pomace ; oleuropein ; tyrosol ; hydroxytyrosol

Sažetak
Introduction: Oleuropein (OLE), tyrosol (TS) and hydroxytyrosol (HTS) are potent antioxidants with use in different commercial sectors such as pharmaceutical, food and chemical industries. They can be obtained in significant amounts from olives, olive leafs and olive mill waste (olive pomace). Along with numerous conventional methods for their extraction from plant material, numerous new methods are currently being established. The aim of this work was to investigate the application of ultrasound-assisted extraction (UAE) for the isolation of these bioactive compounds from olive pomace and to improve the efficiency and sustainability of currently available extraction protocols. Materials and methods: Olive pomace was collected from different olive mills in Croatia during December 2014. Immediately after the oil extraction process samples were frozen and transported to the laboratory. Aliquots of pomace were dried in vacuum-oven to obtain approximately 30% humidity, milled, sieved to remove the kernel particles, homogenized and frozen till analysis. Preliminary investigations showed that among investigated food-grade solvents, 60% ethanol was the most efficient for extraction of OLE TS and HTS from olive pomace. Plant : solvent ratio used was 1:50. Investigated variables were the time of extraction (3, 6, 9, 15, 20, 30 min) ; ultrasound strength (50, 75 and 100 %) ; the type of probe (12 mm and 25 mm) and type of UAE (pulsed and continuous). The results were compared with OLE, HTS and TS yields obtained by optimized conventional solvent extraction (60 % ethanol, 70°C, 120 minutes, with continuous shaking). Results: Obtained results showed that HTs and TS are stabile compounds firmly incorporated into plant matrix. Therefore, more intense extraction conditions are suitable for obtaining satisfying yields in the final extract. The best results were obtained by applying continuous extraction (100% strength) with 12 mm probe for 20 minutes. In comparison to conventional solvent extraction the extraction time was significantly shortened and HTS and TS yields were significantly increased (71.0 and 79.0% respectively). Prolonged extraction (20 minutes), led to partial degradation of OLE ; for obtaining maximum OLE yields, shorter extraction time must be applied (9 minutes). Conclusions:The results of this investigation show that UAE is a promising novel extraction technique for the isolation of OLE, TS and HTS from olive pomace. Under optimized conditions, its application results with significantly higher yields of targeted polyphenolic compounds and significant reduction of energy expenditure and duration of extraction in comparison to convectional extraction technique.

Izvorni jezik
Engleski

Znanstvena područja
Farmacija

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