Pitaya fruit stands out in the world fruit production due to the presence of interesting compounds, such as Phenolics and Betalains. Choosing the proper extraction method is an essential step in obtaining satisfactory bioactive compounds. Thus, the aim of this study was to compare ultrasound-assisted extraction with conventional extraction of Betalains and Phenolic Compounds from pitaya (Hylocereus polyrhizus). The pitaya fruits were purchased at Santa Fé Farm (Garanhuns, PE). The pulp was lyophilized (Christ Alpha 1-4 LD Plus). For ultrasonic extraction, 1 gram of lyophilized pulp was diluted in 40 mL of ethanol (30%), using an ultrasonic probe (soniClean 2PS Sanders medical) for 20 minutes at 275 W, 30 kHz and 25 °C. For conventional extraction, 1 gram of lyophilized pulp was diluted in 40 mL of ethanol (30%) and kept under magnetic stirring for 20 minutes. The supernatants were centrifuged (2000 rpm/20 minutes), filtered and stored in amber glasses (-22°C). Quantification of Betalains (Stintzing et al., 2005) and Phenolic Compounds (Wettasinghe; Shahidi, 1999) was performed. Statistics were performed using the Statistic 7.0 software (StatSoft Tulsa) at a 5% significance level. The extract obtained by ultrasound showed significantly higher levels of Phenolic Compounds (92.78 µg/mL GAE) and Betalains (41.80 mg/L) when compared to conventional extraction (42.06 µg/mL GAE) and (27.11 mg/L), respectively. This factor is related to the effect of cavitation, which provides an increase in cell wall pores, greater contact between solute/solvent, allows mass
transfer and allows for better extraction of bioactive compounds. It can be concluded that the ultrasound-assisted extraction, besides being considered an emerging technique, also presented efficient results in the extraction of Betalains and Phenolic Compounds from pitaya, presenting the possibility of application in the pharmaceutical, cosmetic and food industries.