Application of thermal stability difference to remove flammutoxin in fungal immunomodulatory protein, FIP-fve, extract from Flammulina velutipes

Publication date: July 2018Source: Journal of Food and Drug Analysis, Volume 26, Issue 3Author(s): Ching-Hsin Tung, Chih-Chieh Lin, Huei-Ju Wang, Sung-Fang Chen, Fuu Sheu, Ting-Jang LuAbstractFungal immunomodulatory protein (FIP-fve) is a potential functional food ingredient. However, undesirable component flammutoxin (FTX) would occur in the extracted fraction of FIP-fve. In this paper, an application of heating processing instead of the intensive separation process was employed in fractionation of FIP-fve, meanwhile, exclusion of FTX was reached. Contents of FIP-fve and FTX were monitored by HPLC-UV-ESI-MS. Both FIP-fve and FTX had higher thermal stability in a lower concentration solution. Cold water could effectively extract FIP-fve and FTX from fresh mushroom without acetic acid and disulfide-bond breaking agent β-mercaptoethanol commonly used in biochemical studies. Heating cold water extract contained 580 μg/mL FIP-fve and 452 μg/mL FTX at 60 °C for 5 min could effectively exclude FTX and remain 75% of FIP-fve. Adding 0.1 M trehalose or 20% ethanol did not significantly alter the stability of both proteins. The method developed is an applicable procedure for preparing FIP-fve solution free of FTX.Graphical abstract

Source: Journal of Food and Drug Analysis - July 11, 2018 Category: Food Science Source Type: research