title: Evaluation of the Activities of Antioxidant Enzyme and Lysosomal Enzymes of the Longissimus dorsi Muscle from Hanwoo (Korean Cattle) in Various Freezing Conditions.
abstract: This study was conducted to evaluate the activities of antioxidant enzyme (glutathione peroxidase (GSH-Px)) and lysosomal enzymes (alpha-glucopyranosidase (AGP) and beta-N-acetyl-glucosaminidase (BNAG)) of the longissimus dorsi (LD) muscle from Hanwoo (Korean cattle) in three freezing conditions. Following freezing at -20, -60, and -196℃ (liquid nitrogen), LD samples (48 h post-slaughter) were treated as follows: 1) freezing for 14 d, 2) 1 to 4 freeze-thaw cycles (2 d of freezing in each cycle), and 3) refrigeration (4℃) for 7 d after 7 d of freezing. The control was the fresh (non-frozen) LD. Freezing treatment at all temperatures significantly (p<0.05) increased the activities of GSH-Px, AGP, and BNAG. The -196 ℃ freezing had similar effects to the -20℃ and -60℃ freezing. Higher (p<0.05) enzymes activities were sustained in frozen LD even after 4 freeze-thaw cycles and even for 7 d of refrigeration after freezing. These findings suggest that freezing has remarkable effects on the activities of antioxidant enzyme and lysosomal enzymes of Hanwoo beef in any condition.
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Sun Moon
authors.initials: SM
authors.lastname: Kang
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Geunho
authors.initials: G
authors.lastname: Kang
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Pil-Nam
authors.initials: PN
authors.lastname: Seong
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Beomyoung
authors.initials: B
authors.lastname: Park
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Donghun
authors.initials: D
authors.lastname: Kim
authors.affiliation: Animal Products Research and Development Division, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Korea.
authors.forename: Soohyun
authors.initials: S
authors.lastname: Cho
keywords: Hanwoo beef; antioxidant enzyme; freezing condition; lysosomal enzyme