Optimization of pulsed ultrasound-assisted technique for extraction of phenolics from pomegranate peel of Malas variety: Punicalagin and hydroxybenzoic acids

Abstract

Pomegranate peel is a rich source of phenolic compounds (such as punicalagin and hydroxybenzoic acids). However, the content of such bioactive compounds in the peel extract can be affected by extraction type and condition. It was hypothesized that the optimization of a pulsed ultrasound-assisted extraction (PUAE) technique could result in the pomegranate peel extract with higher yield and antioxidant activity. The main goal was to optimize PUAE condition resulting in the highest yield and antioxidant activity as well as the highest contents of punicalagin and hydroxybenzoic acids. The operation at the intensity level of 105W/cm(2) and duty cycle of 50% for a short time (10min) had a high efficiency for extraction of phenolics from pomegranate peel. The application of such short extraction can save the energy and cost of the production. Punicalagin and ellagic acid were the most predominant phenolic compounds quantified in the pomegranate peel extract (PPE) from Malas variety. PPE contained a minor content of gallic acid.

Extraction of polyphenols and antioxidants from pomegranate peel using ultrasound: influence of temperature, frequency and operation mode

“…On the other hand, the use of pulses in ultrasound‐assisted extraction (UAE) was very effective to improve the extraction of compounds from pomegranate peels (Pan et al ., ; Kazemi et al ., ), as well as from other matrices (You et al ., ; Mohammad et al ., ), requiring shorter time and consuming less energy, solvents and other chemicals (Pan et al ., ; Tiwari, ; Kazemi et al ., ). Regarding phenolic compounds from pomegranate peels, the use of pulses led to an 87% reduction in the processing time and a 22% increase in the yield of antioxidant compounds.…”

“…For all assays, approximately 1.0 g of the sample was mixed with 25 mL of the extracting solvent (70% ethanol in v/v water) and sonicated for 20 min. A previous study reports that 70% ethanol solvent is suitable for the extraction of phenolic compounds using UAE from pomegranate peels (Kazemi et al ., ), and therefore, was the solvent used in this study. After extraction, the extracts were vacuum filtered and the remaining volume was measured.…”

“…The ability of ultrasound to accelerate the extraction and reduce the processing time has been extensively studied for several classes of compounds present in diverse types of samples, including pomegranate peels (Kazemi et al ., ), Artocarpus heterophyllus fruit peel (Moorthy et al ., ), mulberry pulp (Espada‐Bellido et al ., ), orange peels (Khan et al ., ), potato peels (Kumari et al ., ), among others. However, there is limited information on how frequency and mode of application of ultrasound combined with temperature can affect extraction processes.…”

Improvement of microwave‐assisted Soxhlet extraction of bioactive compounds applied to pomegranate peels

“…Comparing bioactive compounds’ content obtained from PP by MASE and results obtained by other extraction technics, it has been shown that MASE allowed to have a higher phenolic content TPC (373 mg GAE/g dw) than 331.28 or 196.70 mg GAE/g dw obtained using high voltage electrical discharge ethanol extraction (Xi, He, & Yan, ) and by water‐ethanol pulsed ultrasound‐assisted extraction (Kazemi, Karim, Mirhosseini, & Abdul Hamid, ), respectively. Similarly, the total flavonoids (TFC) in peel extract obtained my MASE revealed a significantly higher value of 155 mg RE/g dw than 58.63 mg RE/g dw of methanol extraction (Khalil, Khan, Shabbir, & Rahman, ).…”

Green Extraction from Pomegranate Marcs for the Production of Functional Foods and Cosmetics

“…Process conditions of the UAEs were determined using already published results [23,24] after several preliminary trials to adapt them. The details are reported in Table 4.…”