Changes in conformation and in sulfhydryl groups of actomyosin of tilapia (Orechromis niloticus) on hydrostatic pressure treatment

The effect of dynamic high-pressure microfluidization on the activity, stability and conformation of trypsin

“…The exposed SH contents increased from 6.21 ± 0.46 for untreated trypsin to 7.69 ± 0.24, 8.77 ± 0.12 and 9.67 ± 0.13 lmol/g at 80, 100 and 120 MPa, respectively. Similar results of total and exposed SH content changes have been observed in actomyosin (Hsu, Hwang, Yu, & Jao, 2007) and red kidney bean protein isolates (Yin et al, 2008) after HHP treatment. The increase in exposed SH content might be explained by pressure-induced protein unfolding and denaturation while the decrease in total SH contents may be accounted for by the formation of disulphide bonds at high-pressure levels (Yin et al, 2008).…”

The effects of salt concentration on conformational changes in cod (Gadus morhua) proteins during brine salting

“…The results were in accordance with an increase in disulfide bond content. This may be due to either the oxidation of sulfhydryl groups, disulfide interchanges or the formation of hydrogen and hydrophobic bonds (Belitz et al, 2004;Hsu et al, 2007;Ko et al, 2007;Raikos et al, 2007;Sannaveerappa et al, 2004). The total SH groups and available SH groups of the soluble protein fractions extracted with 4 M salt solution were significantly higher than those extracted with the 1 M salt solution.…”

“…changes in secondary and tertiary structure), resulting in an increase in aggregated b-sheet structure and a decrease in a-helical structure of proteins (Carton, Bocker, Ofstad, Sørhem, & Kohler, 2009). This includes changes in reactive groups, such as loss of hydrophilic surface, exposure of hydrophobic areas and sulfhydryl groups that are buried or blocked in native proteins (Belitz, Grosch, & Schieberle, 2004;Hsu, Hwang, Yu, & Jao, 2007). Since the sulfhydryl groups of proteins are exposed, more disulfide bonds are formed due to the increase in interaction of the interior and exterior amino acids Ko, Yu, & Hsu, 2007;Raikos, Campell, & Euston, 2007).…”

Changes in gel properties and water properties of Nemipterus virgatus surimi gel induced by high-pressure processing

“…These results are attributed to protein molecules being forced to unfold under applied pressure, caused the exposure of buried SH groups and increase in reactive SH groups (Omana et al, 2011). Moreover, the reduction in the distance between an SH group causes pressure to promote the formation of disulfide bonds (Hsu, Hwang, Yu, & Jao, 2007). Ramirez-Suarez and Morrissey (2006) also reported that pressure can induce the formation of high-molecularweight polypeptides most likely through disulfide bonding, thereby increasing the breaking force of gels.…”