مقایسه فعالیت آنتی‌اکسیدانی عصاره پوست کیوی (Actinidia Deliciosa L.) استخراج شده به دو روش حمام و پروب فراصوت

ﮔﻴﺎﻫﺎن ﻣﻨﺒﻊ ﻏﻨﻲ از ﺗﺮﻛﻴﺒﺎت فنوﻟﻲ ﻫﺴﺘﻨﺪﻛﻪ ﻣﻬﻤﺘﺮﻳﻦ آنتی‌اکسیدان‌ﻫﺎی ﻃﺒﻴﻌﻲ به شمار ﻣﻲ آﻳﻨﺪ. آنتی اکسیدان ﻫﺎ از ﻋﻮاﻣﻞ اﺻﻠﻲ ﺧﻨﺜﻲ ﻛﻨﻨﺪه رادﻳﻜﺎل ﻫﺎی آزاد ﻣﻲ ﺑﺎﺷﻨﺪ، ﻛﻪ از ﺷﻴﻮع بیماری های مزمن و تخریب بسیاری از ﻣﻮاد ﻏﺬاﻳﻲ ﺟﻠﻮﮔﻴﺮی ﻣﻲ ﻛﻨﻨﺪ. اﻳﻦ ﺗﺮﻛﻴﺒﺎت از ﭘﻮﺳﺖ کیوی ﻧﻴﺰ ﻗﺎﺑﻞ اﺳﺘﺨﺮاج ﻫﺴﺘﻨﺪ. ﭘﺲ از ﺗﻬﻴﻪ پودر ﭘﻮﺳﺖ کیوی، عصاره ﻫﺎ ﺑﻪ دو روش پروب و حمام فراصوت اﺳﺘﺨﺮاج ﺷﺪﻧﺪ. اﺑﺘﺪا ﻣﻴﺰان فنول و ﻓﻼوﻧﻮﺋﻴﺪ کل ﻋﺼﺎره ها اﻧﺪازهﮔﻴﺮی و بعد برای ارزیابی ﺧﻮاص آنتی اکسیدانی ﻋﺼﺎره ﻫﺎی اﺳﺘﺨﺮاج ﺷﺪه از دو روش دی ﻓﻨﻴﻞ ﭘﻴﻜﺮﻳﻞﻫﻴﺪرازﻳﻞ (dpph) و قدرت احیاکنندگی (frap) استفاده و با غلظت 0.1 میلی‌گرم در میلی لیتر آنتی اکسیدان مصنوعی tbhq مقایسه شد. ﻧﺘﺎﻳﺞ ﻧﺸﺎن داد ﻛﻪ ﻣﻴﺰان فنول و ﻓﻼوﻧﻮﺋﻴﺪ کل در عصاره استخراج upaekp بیشتر از ubaekp اﺳﺖ. نتایج آزمون به دام اندازی رادیکال های آزاد dpph نشان داد که غلظت مهار 50% upaekp و ubaekp به‌ترتیب دارای مقادیر 067/ 0 ±0.2 و 035/ ±0 0.28 میلی‌گرم در میلی لیتر است. همچنین در قدرت احیاکنندگی، میزان جذب برای upaekp بیشتر از ubaekp بود. ﻋﺼﺎرهﻫﺎی ﭘﻮﺳﺖ کیوی استخراج شده با هر دو روش فراصوت، ﻓﻌﺎﻟﻴﺖ آنتی اکسیدانی ﻗﺎﺑﻞ ﻗﺒﻮﻟﻲ را ﻧﺸﺎن دادﻧﺪ، با این تفاوت که upaekp نسبت به ubaekp فعالیت آنتی اکسیدانی بالاتری را داشت. بنابراین، عصاره پوست کیوی ﻣﻲﺗﻮاند ﺑﻪ‌ﻋﻨﻮان ﻣﻨبع ﻣﻔﻴﺪی ﺑﺮای ﺗﺄﻣﻴﻦ آنتی اکسیدان های ﻃﺒﻴﻌﻲ ﺑﺎﺷﺪ.

Comparison of Antioxidant Activity of Kiwifruit (Actinidia Deliciosa L.) Peel 's extract extracted by Ultrasound Bath and Probes

Introduction: The peel of fruits, in particular, are an abundant source of natural compounds and contain the higher amount of phenolics compared to the edible portions. Ultrasoundassisted extraction (UAE) is an ideal extraction method capable of producing high quantities of bioactive compounds with a shorter extraction time. Probe and bath systems are the two most common ways of applying ultrasound waves to the sample. Probe sonicators are constantly in contact with the sample and make reproducibility and repeatability difficult. In addition, the risk of sample contamination and foam production is higher. Bath sonicators can act on a range of samples simultaneously and allow for higher reproducibility. Kiwifruit belongs to family Actinidiaceae and genus Actinidia. Kiwifruit is characterized by a high content of vitamin C and other useful compounds such as vitamin E, flavonoids, and minerals. Phenolic compounds present in Kiwifruit peel are catechin, epicatechin, chlorogenic acid, caffeic acid, coumaric acid, and rutin. Several studies have been done on the extraction of various plants with ultrasonic waves. Most of the research on the extraction of plant extracts by ultrasoundassisted under various conditions of parentage such as time, solvent, temperature, and intensity of the sound obtained matched with other traditional methods of extraction and different studies have shown that there was never study on the effects of ultrasound bath and probes under the same conditions (temperature, solvent, time and frequency) on obtained extract and comparison of both two methods has been done. The aim of this study was comparing the antioxidant activity of Kiwifruit peel extract (KPE) obtained by two extraction methods ultrasound bath and probe techniques in same conditions temperature, solvent, time and frequency.; ;Materials and Methods: Hayward Kiwifruit variety was purchased from gardens in Tonekabon City. The peels were dried in the shadow at 2527˚C, and then they were finely ground in a laboratory grinder. The dried peels were pulverized and sieved through a 40mesh sieve to obtain the powdered samples. The dry plant material was then packed in the plastic bag and stored in a freezer at 18˚ C. 10 g of Kiwifruit peel powder was extracted with 100 mL of a mixture of ethanol–water 80% (v/v) at two methods Ultrasound Bath Extraction by using a 25 kHz ultrasonic system (model Elma Sonic S30H, Germany), temperature (45°C), time (20 min) and Ultrasound Probe Extraction by using a 25 kHz ultrasonic system (model VCX 250, Sonics & Materials, Inc., USA), temperature (45°C), time (20 min), amplitude of 45% with a probe of 1 cm in diameter was used. After obtaining extracts, an efficiency of extraction, total phenolic and flavonoid compounds, scavenging activity of 1,1diphenyl2picrylhydrazyl (DPPH) radical, and ferric reducing antioxidant power (FRAP) assay were measured and concentration of 0.1 mg/ml of synthetic antioxidant TBHQ was as the control sample. All data were reported as mean ± standard deviation of three replicates. The results were compared by analysis of variance (ANOVA) using SPSS for Windows [version 16]. Mean differences were significant for extraction efficiency, total phenolic and flavonoid compounds based on Ttest (binary comparison) and other tests based on Duncan 's test at 0.05. Charts were drawn with Microsoft Excel version 2016.; ;Discussion & Results: These results showed that the highest amount of phenolic compounds, flavonoids, extraction efficiency, and antioxidant activity were obtained in UPAEKP. In both extraction methods, with increasing KPE concentration, DPPH free radicals scavenging and ferric reducing antioxidant power also increased. The concentration of 2 mg/ml UPAEKP extracted the highest percentage of inhibition (94.11%) in all of the concentrations of the extracts in two methods. UPAEKP at concentrations of 1.5 and 2 mg/ml and UBAEKP at a concentration of 2 mg/ml showed better performance in scavenging free radicals than TBHQ. Among the extracts, IC50 UPAEKP was 0.2±0.06 mg/ml which was significantly different from UBAEKP (P <0.05). TBHQ at a concentration of 0.1 mg/ml (with a percentage of inhibition of 88.04±0.5) showed a better radical inhibitory activity than the low concentrations of Kiwifruit Peel extracts. UPAEKP with a lower IC50 (0.09±0.07) showed more reducing antioxidant power than UBAEKP. TBHQ at a concentration of 0.1 mg/ml (with an absorption rate of 304/1) had greater reducing antioxidant power than the Kiwifruit Peel extracts at all concentrations except the concentration of 2 mg/ml UPAEKP. In this study, the extraction of KPE with both ultrasound methods was acceptable in terms of efficiency and antioxidant activity, with the difference that the probe superior to the ultrasound bath. Therefore, according to the results, KPE was competitive with TBHQ activity. KPE can be used as a useful source to provide natural antioxidant, and the probe compared with the ultrasound bath is a better way of extracting the KPE phenolic compounds.