Effect of different extraction methods on saffron antioxidant activity, total phenolic and crocin contents and the protective effect of saffron extract on the oxidative stability of common vegetable oils

Abstract

Saffron consists of bioactive compounds with health-promoting properties and is mainly used in medicine, flavoring and coloring. In this study, we aimed to investigate the effect of extraction methods on the antioxidant activity of saffron (Crocus sativus L.) extracts (SE) and to evaluate the antioxidant performance of SE in vegetable oils. Saffron stigmas were extracted in water, ethanol, methanol, and their combinations using maceration extraction (ME), ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), and the combination of UAE with MAE. The results showed that the sample extracted by methanol/water (50:50) using the combination of UAE with MAE methods had the highest amount of total phenolic content (31.56 mg/g GAE) and antioxidant activity (83.24% inhibition). The extract with the highest antioxidant activity was freeze-dried before incorporation into oil samples. Freeze-dried SE contained trans-crocin-4 and trans-crocin-3 (most abundant constituents), kaempferol, and picrocrocin. Moreover, the addition of SE at 1000 ppm resulted in a significant increase in the oxidative stability of canola (CAO), sunflower (SO), and corn oil (COO).

The effect of harvest time on the volatile compounds and bioactive properties of the flowers, leaves, and stems of Echinacea Pallida and its utilization to improve the oxidative stability of vegetable oils

“…Yalcin et al (2017) reported that the IP of corn oil without and with 2000 ppm of grape seed extract changed from 3.18 to 3.31 -3.41, depending on the seed variety. In another study, saffron extract (1000 ppm) had a similar effect (p < 0.05) with BHT (200 ppm) in preventing the oxidation of vegetable oils (Najafi et al, 2022) The volatile compounds in the flower, leaf, and stem parts of E. Pallida harvested in June, 2009, June, 2010 and August, 2010 are shown in Table 3. Bornyl acetate, caryophyllene E, musk ambrette, germacrene D, α-cubebene, α-copaene, α-humulene, α-muurolol, γ-cadinene, and caryophyllene oxide are some of the major volatile compounds which were identified in all the plant parts of E. pallida.…”

Stigmas and Petals of Crocus sativus L. (Taliouine, Morocco): Comparative Evaluation of Their Phenolic Compounds, Antioxidant, and Antibacterial Activities

“…The variability in antimicrobial potential recorded by the authors is linked to several direct and indirect factors that accompany the sample from implantation to the final product. These factors include the age of the corms [ 55 ], altitude and climate [ 60 ], drying temperature [ 61 ], storage and packaging [ 62 ], and extraction and analysis methods [ 36 , 63 ]. All these factors can affect the chemical composition of the sample and therefore the results obtained during analysis.…”

The Multifaceted Therapeutic Potential of Saffron: An Overview Based on Research and Patents

“…Moreover, the sensory perception of saffron is closely related The key bioactive compounds are all derived from the carotenoid precursor zeaxanthin through different biosynthetic pathways during the development and drying process of saffron stigmas [26,27]. Briefly, zeaxanthin undergoes oxidative cleavage by the enzyme carotenoid cleavage dioxygenase to form the apocarotenoid crocetin dialdehyde, which is subsequently converted to crocetin (C 20 H 24 O 4 ) by an aldehyde dehydrogenase [27][28][29]. Crocetin then follows two parallel pathways:…”

“…Crocetin is glucosylated by glucosyltransferases to form crocins (crocetin glycosides), primarily crocin-4, by the addition of gentiobiose (GeOH: C 12 H 22 O 11 ), a disaccharide of two glucose units [27][28][29]. In summary: Crocetin + GeOH → Crocin.…”

“…Zeaxanthin is also converted to picrocrocin (C 16 H 26 O 7 ), a colorless monoterpene glycoside and precursor of the saffron aroma component, a monoterpene glycoside, through a separate pathway [28,29]. During the drying and processing of saffron stigmas, the enzyme β-glucosidase acts on picrocrocin, cleaving it to release safranal (C 10 H 14 O) and D-glucose (GlOH: C 6 H 12 O 6 ) [28][29][30]. In summary: Picrocrocin → Safranal + GlOH.…”