Food Chemistry
Mahshid Zamankhani; Sohrab Moeini; Peyman Mahasti Shotorbani; Hossein Mirsaeedghazi; Afshin Jafarpour
Abstract
This study aimed to investigate antimicrobial and antioxidant activities of borage (Echium amoenum L.) and hollyhock (Althaea rosea var. Nigra) extracts. The extracts were obtained through soaking and ultrasound- assisted methods using water or methanol as a solvent. The total phenols and flavonoid, ...
Read More
This study aimed to investigate antimicrobial and antioxidant activities of borage (Echium amoenum L.) and hollyhock (Althaea rosea var. Nigra) extracts. The extracts were obtained through soaking and ultrasound- assisted methods using water or methanol as a solvent. The total phenols and flavonoid, anthocyanin content, free radical scavenging activity, ferric reducing antioxidant power, and antibacterial capacity of the extracts were determined. Phenolic acids were identified using the HPLC chromatogram. It was found that the ultrasound-assisted extraction was more efficient compared to the soaking method. The results showed that in the TPC, anthocyanins, and the FRAP tests, the highest amount was related to the samples extracted using the ultrasound- assisted method with water as solvent. The highest amount of TFC was obtained through a soaking method using methanol as the solvent. Anti- radical activity of the samples indicated that using water as a solvent in the optimum method resulted in a higher antioxidant activity. Furthermore, bacterial alpha amylase inhibition test signified that the inhibitory effect was boosted by increasing the extract concentration. The HPLC analysis of the borage and hollyhock extracts revealed that gallic acid and Syringic acid were the most prominent phenolic compounds. Generally, the results showed a good antibacterial property against Staphylococcus aureus for borage and hollyhock extracts. The results give us valuable insight into the potential therapeutic and medicinal applications of borage and hollyhock as a natural preservative to improve immunity.
Maryam Modanlow; Gholamreza Rafiee; Ali Motamedzadegan; Sohrab Moeini; Alireza Mirvaghefi; Mahmoudreza Ovissipour
Abstract
In present paper the optimum extraction condition of protein of Hydrolysate from the viscera of yellow fin tuna (Thunus albacores) were studied. Enzyme hydrolysis has been performed at enzyme to substrate ratio: 1.3-3.7 mg/gr.protein , time of reaction: 1-10 hours, temperature: 30-44 ºC and using RSM ...
Read More
In present paper the optimum extraction condition of protein of Hydrolysate from the viscera of yellow fin tuna (Thunus albacores) were studied. Enzyme hydrolysis has been performed at enzyme to substrate ratio: 1.3-3.7 mg/gr.protein , time of reaction: 1-10 hours, temperature: 30-44 ºC and using RSM method and central composite design(CCD) with 4 repetitions at central point and five levels of each treatment. Results have been compared with average at statistical level where α = 0.05. According to results,the protein recovery increases with an increase in enzyme activity from 1.3 to 2.5 mg When enzyme activity increases to 3.35 mg, the protein recovery reaches a constant level and then decreases with an extra increase of enzyme amount to 3.7 mg.The rate of protein recovery increases, With an increase in temperature from 30 ºC to 37 ºC,And then the enhancement of recovery rate decreases with more increase of temperature from 37ºC to 42ºC, However it will remain constant for temperatures beyond 42ºC.The protein recovery decreases With increasing the hydrolysis time between 60 to 138 min. and it reaches a stationary phase somehow during 138 to 330 min.In optimum point of hydrolysis, protein recovery was 75%. This condition were observed in enzyme ratio of 2.41 mg ,Temperature of 38.75ºC,and hydrolysis time of 570 min. Results showed that protein recovery is mainly influenced by ratio of enzyme to substrate rate and temperature ,while time of hydrolysis should be considered as a function of temperature and enzymatic ratio.
Keywords: Protein hydrolysate, Protein recovery, Optimization, Waste of yellow fine tuna, Trypsin
