Screening of squalene-containing raw materials growing in the Russian Federation

Objectives. The work set out to analyze plant sources with the highest squalene content growing in the Russian Federation: Styrian pumpkin seeds, wheat sprouts, corn grains, grape seeds, Amaranthus caudatus seeds, Emperor amaranth seeds, Voronezhsky amaranth seeds, Kines amaranth seeds, Giant amaranth seeds. In order to evaluate the squalene content in the raw materials and identify the most promising sources, oil extraction and subsequent isolation of the unsaponifiable fraction from plant raw materials was carried out.

Methods. Oil extraction from plant raw materials was carried out by means of a Soxhlet apparatus with subsequent saponification of the obtained fraction and purification with n -hexane. Quantitative determination of squalene was carried out by high-performance liquid chromatography with diode array detection. The concentration of squalene in the test solutions was determined according to the calibration graph.

Results. After extracting oil from the plant material using a Soxhlet apparatus, the content of the oil was determined. The quantitative content of squalene was determined from the unsaponifiable fraction obtained from each oil sample in order to identify the species and variety of plant material that is the richest in squalene.

Conclusions. While the highest oil content was found in Styrian pumpkin seeds (35%) and grape seeds (10%), these extracts had a low (less than 1%) squalene content. A similarly low content was observed in corn grains and wheat sprouts. Among the studied amaranth varieties, a comparable oil content was found (6–8%), with the lowest value obtained in the Voronezhsky amaranth seeds (6.1%) and the maximum in the Kines amaranth seeds (7.9%). The squalene content in different types of amaranth seeds varied from 0.13 to 0.21%, of which the maximum value belongs to the Emperor amaranth seeds. This trend was observed both in the oil and in the unsaponifiable fraction. This makes this seed variety a promising source for commercial extraction of squalene.

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