Mahsa Alikhani Faradonbeh; Reza Esmaeilzadeh kenari; Maryam Ghaderi
Abstract
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. Ultrasound-assisted extraction (UAE) is an ideal extraction method capable of producing high quantities of bioactive compounds with ...
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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. Ultrasound-assisted 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 ultrasound-assisted 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 25-27˚C, and then they were finely ground in a laboratory grinder. The dried peels were pulverized and sieved through a 40-mesh 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 1,1-diphenyl-2-picrylhydrazyl (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 T-test (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 UPAE-KP. 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 UPAE-KP extracted the highest percentage of inhibition (94.11%) in all of the concentrations of the extracts in two methods. UPAE-KP at concentrations of 1.5 and 2 mg/ml and UBAE-KP at a concentration of 2 mg/ml showed better performance in scavenging free radicals than TBHQ. Among the extracts, IC50 UPAE-KP was 0.2±0.06 mg/ml which was significantly different from UBAE-KP (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. UPAE-KP with a lower IC50 (0.09±0.07) showed more reducing antioxidant power than UBAE-KP. 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 UPAE-KP. 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.
Vida Mardani Ghahfarokhi; Mehran Alami; Saeedeh Arabshahi- Delouee; Rasul Khoda Bakhshi; Maryam Ghaderi
Abstract
Evening primrose (Oenothera biennis) is a biennial flowering plant increasingly cultivated for medicinal use of γ-linolenic acid rich oil of its seeds. In this study, total phenolic and flavonoids content, antioxidant and antimicrobial activity of aceton, ethanolic and metanolic extracts of evening ...
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Evening primrose (Oenothera biennis) is a biennial flowering plant increasingly cultivated for medicinal use of γ-linolenic acid rich oil of its seeds. In this study, total phenolic and flavonoids content, antioxidant and antimicrobial activity of aceton, ethanolic and metanolic extracts of evening primrose flowers were evaluated. Aceton extract had the highest extraction yield, total phenol and flavonoids content. Extracts were also tested for their antioxidant activity using scavenging activity of 2,2- diphenyl-1-picrylhydrazyl and reducing power of Fe+3 in comparision with BHT. BHT was the highest in DPPH radical scavenging and reducing power followed by aceton, ethanolic and methanolic extracts. The extracts also showed good antibacterial activity against all of tested microorganism and the tested gram-negative bacteria was more resistant to inhibitory effect of extracts. Among different bacteria tested, Salmonella. typhimurium was found to be the most resistant to aceton and ethanolic extracts. The MBC values, with respect to aceton and ethanolic extracts for Salmonella. typhimurium were 10 and 20 (μg/ml), respectively
Maryam Ghaderi; Alireza Sadeghi Mahoonak; Mehran Alami; Morteza Khomeiri; Rahil Rezaei
Abstract
In this study, total phenolics and flavonoids content, antiradical and antimicrobial activity of methanolic extract of two Iranian acorn varieties, namely Quercus.castaneifolia var castaneifolia and Quercus.branti var persica were evaluated. Total phenolic and flavonoid content and extraction yield of ...
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In this study, total phenolics and flavonoids content, antiradical and antimicrobial activity of methanolic extract of two Iranian acorn varieties, namely Quercus.castaneifolia var castaneifolia and Quercus.branti var persica were evaluated. Total phenolic and flavonoid content and extraction yield of methanolic extract of castaneifolia variety (MC) were significantly higher than that of the extract of persica variety (MP). Extracts were also tested for their antioxidant activities using scavenging activity of 2, 2-diphenyl-1-picrylhydrazyl and compared with synthetic antioxidant namely BHA and BHT. EC50 values for MC, MP, BHA and BHT were 42.84, 70.40, 89.46 and 41.73 mg/ml, respectively. The extracts also showed good antimicrobial activity against all of tested microorganisms and the tested gram-negative bacteria was more resistant to the inhibitory effect of extracts. The ranges of minimum inhibitory concentration (MIC) of the extracts were 0.312-5 and 1.25-5 mg/ml for MC and MP, respectively. There was no difference between the MIC of MC and MB extract against Salmonella typhi and Shigella dysenteriae but MC extract showed the strongest activity on Escherichia coli and Yersinia entrocolitica at lower concentration. MP extract at concentration of 5mg/ml had bactericidal effect on all of gram negative bacteria (except Citrobacter). The most efficient bactericidal activity of MC extract was against Bacillus cereus, with MBC = 0.312 mg/ml while Shigella dysenteriae had the highest MBC (10mg/ml). A high-performance liquid chromatography was used for determination of phenolic acids of extracts. gallic, caffeic, p-coumaric and cholorogenic acid were found in MC and Gallic, caffeic, cholorogenic and sirinjic acid were detected in MP extract.
Keywords: Acorn fruit, Antimicrobial activity, Gallic acid, Methanolic extract, Phenolic Compounds
