Extraction of crocin from saffron (Crocus sativus) using molecularly imprinted polymer solid-phase extraction

• Published in: Journal of separation science 2010-08, Vol.33 (15), p.2302-2309
• Main Authors: Mohajeri, Seyed Ahmad, Hosseinzadeh, Hossein, Keyhanfar, Fariborz, Aghamohammadian, Javad
• Format: Article
• Language: English
• Subjects: Affinity; Aroma and flavouring agent industries; Binding sites; Biological and medical sciences; Biopolymers - chemistry; Blanks; Carotenoids - chemistry; Carotenoids - isolation & purification; Crocin; Crocus - chemistry; Disaccharides - chemistry; Extraction; Food industries; Fundamental and applied biological sciences. Psychology; General pharmacology; Imprinted polymers; Medical sciences; Molecular Imprinting; Molecularly imprinted polymer; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Plant Extracts - chemistry; Purification; Recovery; Saffron; Solid Phase Extraction - methods; SPE
• ISSN: 1615-9306; 1615-9314; 1615-9314
• DOI: 10.1002/jssc.201000183

A new molecularly imprinted polymer for extraction of crocin from saffron stigmas was prepared using gentiobiose (a glycoside moiety in crocin structure) as a template. Crocin binding to gentiobiose imprinted polymer (Gent-MIP) was studied in comparison with a blank nonimprinted polymer in aqueous media. Affinity of the Gent-MIP for the crocin was more than the nonimprinted polymer at all concentrations. In Scatchard analysis, the number of binding sites in each gram of polymer (maximum binding sites) and dissociation constant of crocin to binding sites were 18.4 μmol/g polymer and 11.2 μM, respectively. The Gent-MIP was then used as the sorbent in an SPE method for isolation and purification of crocin from methanolic extract of saffron stigmas. The recovery of crocin, safranal and picrocrocin was determined in washing and elution steps. The Gent-MIP had significantly higher affinity for crocin than other compounds and enabled selective extraction of crocin with a high recovery (84%) from a complex mixture. The results demonstrated the possibility of using a part of a big molecule in preparing a molecularly imprinted polymer with a good selectivity for the main structure.