A. D. Rodriguez-Lopez et al. / Agricultural Sciences 4 (2013) 45-50
Copyright © 2013 SciRes. OPEN ACCESS
2.0 U/mg∙prot. obtained for the ultrasound-assisted me-
thod. Hence, conventional extraction led to higher PME
effectiveness in the extracts than the ultrasound-assisted
extraction.
4. CONCLUSIONS
Variables studied (pH, [NaCl] and t), had different ef-
fect on the PME activity, protein content and PME effec-
tive ness ( ηPME) in extracts for the co nventional extra ction:
For PME activity, [NaCl] and pH were significant and
had positive effect; for protein content, pH was highly
significant with positive effect while, [NaCl] was less
significant with a negative effect; for the ηPME, [NaCl]
was found significant with positive effect. Model equa-
tions describing the PME activity, protein content and
ηPME of the extracts presented adequate regression coef-
ficients. Experimental conditions that maximize ηPME
were: pH = 5.9, [NaCl] = 2.5 M and time = 20 min.
For ultrasound-assisted extraction, PME activity, pro-
tein content and ηPME showed a similar hyperbolic beha-
vior with ti me course d uring e xtraction. T he stabilization
time was around 15 min in both cases.
Comparing results for both extraction methods at the
same extracting conditions (pH = 5.5; NaCl = 1.25 M; t
= 15 min), conventional extraction led to slightly higher
PME effectiveness than the ultrasound-assisted extrac-
tion, what is interesting in future ind ustrial a pplications.
5. ACKNOWLEDGEMENTS
Authors acknowledge the Vicerrectorado de Investigación of the
Universidad Politecnica de Valencia for the financial support (project
1965) from the call Proyectos de Nuevas Líneas de Investigación Mul-
tidiscipli nares (PAID05-11 ).
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