Extraction of Polyphenols and Valorization of Fibers from Istrian-Grown Pomegranate (Punica granatum L.)

Abstract

Pomegranate fruit is an ancient fruit that is used not only because of its deep-red color and tasty arils but also due to the health benefits of its extracts. Pomegranate is a valuable source of bioactive compounds, including colorful anthocyanins and other polyphenols. The main objective of the present study was to gain comprehensive knowledge of the phenolic composition and antioxidative activity of a new pomegranate cultivar, grown in Northwest Istria, a part of the North Adriatic coastal area. Various parts of the pomegranate fruit parts were extracted in 70% ethanol or water. Total phenolic content and antioxidative capacity were respectively determined with Folin–Ciocalteu reagent and ABTS radical. Phenolics were examined and analyzed with TLC, LC-MS, and HPLC. Pomegranate juice was prepared from red arils and after thermal treatment, the stability of anthocyanins was monitored for several months to understand the effect of storage. The highest total phenolics were determined in ethanol pomegranate peel extracts (30.5 ± 0.6 mg GAE/g DM), and water peel extracts exhibited the highest antioxidative activity (128 ± 2 µg TE/g DM). After five months of storage of thermally treated pomegranate juice, 50–60 percentage points increase in anthocyanin degradation was observed. Pomegranate peel was further tested as a sustainable inedible food source for papermaking. Due to the low content of cellulose and the high percentage of extractives, as well as a distinguished texture and appearance, the paper made from pomegranate peel is best suited for the production of specialty papers, making it particularly interesting for bioactives recovery, followed by material restructuring.

Potential Anticancer Activity of Pomegranate (Punica granatum L.) Fruits of Different Color: In Vitro and In Silico Evidence

“…Particularly, ellagitannins [ 43 ] and ANTO [ 44 ] have potent antiproliferative and pro-apoptotic activity against several cancer cells including those of the colon, breast, lung, cervix, prostate, liver, and oral/esophageal, to name a few. Although the extractive methodology and chromatographic conditions used in this study did not allow the identification of complex ellagitannins (e.g., punicalagin), as it has been reported for “Wonderful” and “Mollar de Elche” varieties by others [ 37 , 38 , 39 , 40 , 41 ] that the presence of ellagic acid and two of its glycosides in all three varieties of PMG (pink > red, white; Table S1 ) accounts for this. PMG´s ellagitannin-derived compounds (e.g., ellagic and gallagic acids, and urolithins A/B and B) not only have a high RSC but also antimutagenic activity [ 42 , 45 ].…”

“…It is noteworthy that the PC profile (molecular diversity and content) of PMGs depends on the fruit´s ripening stage, phenogenotype, pre/post-harvest conditions, and extractive solvent, among other factors [ 37 ]. Nevertheless, the flavonoid: total PC and ANTO: flavonoid ratios and ANTO fingerprint (cyanidin > delphinidin > pelargonidin, di > mono glucosides) are quite conserved among PMGs of different phenogenotypes and regions [ 8 , 37 , 38 , 39 , 40 , 41 ]. Also, while red PMG was a richer source of ANTO and organic acids, white and pink were richer in phenolic acids ( Table S1; see Supplementary Materials ).…”

Preparation and Characterization of Polycaprolactone (PCL) Antimicrobial Wound Dressing Loaded with Pomegranate Peel Extract

“…The results showed that the content of polyphenols in PPE was 135.30 mg/g. Skrt et al 28 also used the ethanol solvent extraction method to extract polyphenols in pomegranate peel, and the yield of extracted polyphenols was 30.5 mg/g after optimizing the extraction conditions. This value was lower than the amount of extracted polyphenols in this study.…”

The Role of Isoflavones in the Prevention of Breast Cancer and Prostate Cancer

“…In plants, polyphenols have an important role as a part of the plant's defense mechanisms against different pathogens. Polyphenols are present in the human diet since they can be found in different fruits [12][13][14][15][16][17] and vegetables [18], medicinal plants [19][20][21][22] as well as other products such as vines [15] and bee products [21,[23][24][25]. Differences in the quantity of polyphenols and their bioavailability for humans depend on plant type, food product, etc.…”