The denaturation study of myoglobin by DTAB from two slaughtering methods

It has recently been shown that the consumption of halal meat is developing around the world. Investigations have demonstrated that different type of slaughtering was affected on biochemical composition, physical and microbial properties of meat. The aim of this study was to assess the effects of two different slaughtering: Halal slaughtering (Hs) and Industrial slaughtering (Is) on structural changes of myoglobin (Mb) as an indicator of meat proteins upon interaction with dodecyltrimethylammonium bromide (DTAB) using the UV-vis absorption and circular dichroism (CD). The UV-Vis absorption spectra between 200 and 650 nm was used to identify structural changes upon interaction with DTAB. As DTAB concentration increased, the maximum intensity absorption (411 nm) in two type of sample decreased and the peak wavelengths for OxyMb (542 nm 581 nm) converted to MetMb peak wavelength (503 and 632). The further blue shift of Soret band and more absorbance changes around 275 nm was demonstrated in non-halal during surfactant titration, the broad and asymmetric Soret band in non-halal Mb may be caused by the coexistence of two pentacoordinated species. The circular dichroism (CD) was utilized to obtain secondary structure and compactness for Mb upon interaction with DTAB, with increasing DTAB concentration, α-helicity of non-halal Mb decreases more strongly than halal Mb. It can be concluded that halal Mb was more compacted relative to non-halal Mb and by increasing surfactant.In addition, our result suggest that with increasing DTAB the transition of halal oxyMb to the state of hemichrome occurred at a slower speed than non-halal oxyMb.