Identification of VOCs in essential oils extracted using ultrasound- and microwave-assisted methods from sweet cherry flower

Abstract

The floral fragrance of plants is an important indicator in their evaluation. The aroma of sweet cherry flowers is mainly derived from their essential oil. In this study, based on the results of a single-factor experiment, a Box–Behnken design was adopted for ultrasound- and microwave-assisted extraction of essential oil from sweet cherry flowers of the Brooks cultivar. With the objective of extracting the maximum essential oil yield (w/w), the optimal extraction process conditions were a liquid–solid ratio of 52 mL g−1, an extraction time of 27 min, and a microwave power of 435 W. The essential oil yield was 1.23%, which was close to the theoretical prediction. The volatile organic compounds (VOCs) of the sweet cherry flowers of four cultivars (Brooks, Black Pearl, Tieton and Summit) were identified via headspace solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). The results showed that a total of 155 VOCs were identified and classified in the essential oil from sweet cherry flowers of four cultivars, 65 of which were shared among the cultivars. The highest contents of VOCs were aldehydes, alcohols, ketones and esters. Ethanol, linalool, lilac alcohol, acetaldehyde, (E)-2-hexenal, benzaldehyde and dimethyl sulfide were the major volatiles, which were mainly responsible for the characteristic aroma of sweet cherry flowers. It was concluded that the VOCs of sweet cherry flowers were qualitatively similar; however, relative content differences were observed in the four cultivars. This study provides a theoretical basis for the metabolism and regulation of the VOCs of sweet cherry flowers.

Mineral Content and Volatile Profiling of Prunus avium L. (Sweet Cherry) By-Products from Fundão Region (Portugal)

“…Notably, benzaldehyde was found in all cherry by-product extracts in significant amounts ( Table 3 ). These results are in agreement with the study by Zhang et al [ 35 ], who detected this compound and ( E )-2-hexenal in the sweet cherry flowers of cultivars Brooks, Black Pearl, Tieton, and Summit. This benzaldehyde has a sweet, floral, and spice-like odor and is widely used by the cosmetic and food industries as an aliphatic fragrance and flavor material [ 36 ].…”

“…2-Ethyl-1-hexanol was the alcohol present in large amounts in most P. avium by-product extracts ( Table 3 ). Compared to other studies, 2-ethyl-1-hexanol was also the predominant alcohol found in cherries [ 5 ] and their flowers [ 35 ]. Phenylethyl alcohol was found mainly in stems and flowers, and it is an important flavoring ingredient.…”

“…Lilac aldehydes (20, 21, and 25) were found in all cherry flower extracts ( Table 3 ). These compounds are olfactory molecules of great interest to pollinators, and they are commonly found in P. avium flowers [ 35 ], Syringa vulgaris L. [ 42 ], and bee pollen [ 43 ]. The lilac aldehydes in cherry flowers are characteristic aroma components [ 35 ].…”

“…Phenylethyl alcohol was found mainly in stems and flowers, and it is an important flavoring ingredient. Moreover, this compound is one of the main aroma constituents of rose essential oil, and its fresh and sweet smell has calming effects as well as anti-inflammatory and antibacterial effects [ 35 ]. No alcohols were found in any of the sweet cherry leaf extracts ( Table 3 ).…”

Otimização da extração assistida por ultrassom de compostos bioativos da espécie Caryocar brasiliense

“…No processo de extração via ultrassom os possíveis parâmetros que influenciam na extração de metabólitos secundários são: concentração da amostra, proporção de solvente, tempo de extração e temperatura (Ghitescu, et al, 2015). Desse modo, a utilização de ferramentas estatísticas, tais como o planejamento fatorial e a superfície de resposta, vêm sendo empregadas, a fim de explorar condições experimentais de sistemas com um menor número de análises (El-Naggar, et al, 2021;Yuan, et al, 2018;Zhang, et al, 2021). O planejamento Box-Behnken por exemplo, é uma metodologia que utiliza tais ferramentas para o auxílio na definição de quais as melhores condições para extração dos analitos de interesse.…”