Ultrasound-Assisted Saponification Coupled with Gas Chromatography-Flame Ionization Detection for the Determination of Phytosterols from Passion Fruit Seed Oil

Abstract

An ultrasound-assisted saponification (UAS) method for the determination of phytosterols (campesterol, β-sitosterol and stigmasterol) in passion fruit seed oil, followed by gas chromatography with flame ionization detection, was developed and validated. Under the optimum conditions, good linearity with correlation coefficients higher than 0.99 was obtained for all analytes. The recoveries for the proposed approach were between 103 and 107%, the limits of quantification were between 70 and 180 μg kg -1 and the precision values expressed in terms of relative standard deviations (RSD) were lower than 19%. The developed method was successfully applied to the analysis of passion fruit seed oil samples from different species, including yellow passion fruit, sweet granadilla and sweet passion fruit. In all species of analyzed passion fruit seed oils, β-sitosterol was found with the highest abundance, ranging from 0.90 ± 0.02 to 1.60 ± 0.01 mg g -1 of oil, followed by stigmasterol (0.70 ± 0.01 to 1.40 ± 0.12 mg g -1 of oil) and campesterol (0.10 ± 0.01 to 0.30 ± 0.06 mg g -1 of oil). Furthermore, the developed method proved to be a time-saving and efficient analytical procedure for the determination of phytosterols in oil samples.Keywords: Passiflora species, campesterol, β-sitosterol, stigmasterol IntroductionPassiflora species are cultivated throughout the world in tropical areas.1-3 Passiflora edulis f. flavicarpa (yellow passion fruit), Passiflora alata (sweet passion fruit), Passiflora ligularis (sweet granadilla) and Passiflora edulis Sims (purple passion fruit) are species widely cultivated for their edible fruits. [4][5][6] Yellow passion fruit is the species most known and appreciated due to its organoleptic properties, such as an intense flavor and slight acidity. The pulp is destined for in natura consumption, but is predominantly used in juice production. 2,4 Furthermore, the pulp is known to be rich in bioactive compounds, such as carotenoids, phenolic compounds and vitamins A, C and D. 2,7 The large-scale production of passion fruit juice generates tons of by-products (peel and seeds) that are important raw materials in the food and cosmetic industries. 8 Recently, several studies have described that passion fruit peel is a source of fiber, predominantly pectin, which provides it with a range of potential applications as a stabilizer, emulsifier and as a thickening and gelling agent for the preparation of food products, e.g., functional beverages, mayonnaise and ice cream toppings. [8][9][10][11][12] In addition, it has been reported that passion fruit peel presents antioxidant activity and phenolic compounds. 5,13,14 Alternatively, passion fruit seeds are described as a rich source of lipids, proteins, minerals and fibers.14-16 Several studies have reported that passion fruit seeds contain about 30% oil, with linoleic, oleic and palmitic acids as the main fatty acids.14,15,17 Furthermore, as well as the peel, passion fruit seed oil has been described as a potential source of bioactive compounds, such as p...

Obtaining oil from macauba kernels by ultrasound-assisted extraction using ethyl acetate as the solvent

“…UAE promoted a greater extraction of these compounds (p < 0.05), obtaining 65.96 mg per 100 g of oil. Rotta et al (2018) and Silva et al (2017) extracted the oil from passion fruit and radish seeds, respectively, and reported that under the conditions evaluated the oil obtained by ultrasound showed a greater concentration of phytosterols when compared to conventional extraction. Possibly, ultrasound favoured the selectivity of these compounds, mainly due to the shorter contact time between the solvent and the sample, as well as the greater agitation (cavitation) of the system, promoting a more effective breakdown of the interactions and release of the compounds.…”

Development and application of green and sustainable analytical methods for flavonoid extraction from Passiflora waste

“…The extracting phenomenon for MAE is similar to UAE, except it applies thermic waves instead of ultrasounds waves. The difference between MAE and other heating mechanisms are the heat exchange directions, which also occurs from the inside of cells to the outside due to the microwave radiation, enhancing cell rupture and the release of the analytes [ 30 , 45 , 46 ]. MAE and UAE techniques are promising alternatives for flavonoid study in plant matrixes such as passion fruit.…”

Serum Cholesterol-Lowering Activity of β-Sitosterol Laurate Is Attributed to the Reduction of Both Cholesterol Absorption and Bile Acids Reabsorption in Hamsters

“…The extraction method of the total lipids in the feces was consistent with those in the liver described above. After extraction, cholesterol and β-sitosterol were purified from the total lipids through a saponification reaction on the guidelines of Rotta et al with a little modification. Specifically, the extraction was stirred and saponified with 10 mL 1 mol/L 70% NaOH ethanol solution at 70 °C for 1 h. After the reaction, cholesterol and β-sitosterol were extracted by 10 mL cyclohexane three times, washed with water to pH 7, and detected by HPLC.…”