바질은 세계적으로 가장 많이 쓰이는 허브이자 최근 우리나라에서도 생산과 소비량이 급증하고 있는 가운데, 저온저장 유통시 저온장해로 인한 상품성 저하가 농가의 수익을 저해하는 주요 원인이 되고 있다. 따라서 본 연구는 Basil(Ocimum basilicum L.)을 수확하여 4℃에 12시간동안 저온저장하기 전에, 12℃에 각각 0, 4, 8, 12, 16 및 24시간 동안 예냉 처리하였다. 예냉과 냉장저장 처리 후 항산화효소인 APX (Ascorbate peroxidase), SOD(Superoxide dimutase) 및 CAT (Catalase peroxidase)의 활성을 조사한 결과는 아래와 같다. 수확된 잎이 12℃ 예냉 처리 없이 4℃ 저온에 12시간 저장되었을 때 APX 활성은 112μmol/min/mg protein로 수확 직후의 APX 활성도인 186 μmol/min/mg protein의 40% (P < 0.05) 수준이었다. APX 활성은 12℃에 16시간 예냉 처리된 잎에서 가장 높은 수준인 187μmol/min/mg protein을 보였다. 예냉 처리 기간이 16시간 보다 많은 24시간을 처리 한 경우 APX 활성은 낮아지는 것으로 나타나 적정 예냉 기간은 16시간 보다 길지 않아야 한다고 고찰된다. 반면, SOD(Superoxide dimutase)와 CAT (Catalase peroxidase) 활성은 모든 예냉 처리에 따른 유의차를 보이지 않았다. 본 실험에서 얻은 데이터들을 종합해 볼 때 Basil의 수확 후 예냉 처리는 반드시 필요하다는 것을 알 수 있고, APX 효소 활성도가 SOD와 CAT 효소 활성도 보다 Basil의 저온 스트레스로 인한 생리적 반응의 좋은 지표인 것으로 보인다.
Basil is one of popular culinary herbs in the world, and recently production and consumption have been increased in Korea. Chilling injury by storage temperature during cold storage transportation is a major factor to decrease its marketable value as well as growers income. This study aimed to investigate the effects of pre-cooling treatments prior to cold storage on activities of antioxidant enzymes of basil (Ocimum basilicum L.). Harvested basil leaves were pre-cooled in a chamber controlled at 12℃ for 0, 4, 8, 12, 16 and 24 hours prior to storage at 4℃ for 12 hours. After completion of pre-cooling and cold storage treatments, the activities of APX (Ascorbate peroxidase), SOD (Superoxide dimutase), and CAT (Catalase peroxidase) were measured. When the harvested leaves were placed in a chamber controlled at 4℃ for 12 hours without application of pre-cooling at 12℃, the APX activity was decreased by 40 % (P < 0.05), about 112 μmol/min/mg protein, compared to the level measured immediately after the leaves were harvested, 186 μmol/min/mg protein. In contrast, the highest level of APX activity was observed in the leaves treated with 16 hour-precooling at 12℃, about 186 μmol/min/mg protein. The APX activity in the leaves under longer-term pre-cooling application, 24 hours, was lower than those of leaves under 16 hours, indicating that proper length of pre-cooling treatment should not be longer than 16 hours. However, the activities of both SOD and CAT were not significantly affected by the pre-cooling treatments. All the integrated data suggest that pre-cooling treatment prior to cold storage is necessary to avoid chilling injury, and the APX enzyme appears to be a better indicator for physiological response of basil leaves to chilling injury than SOD and CAT enzymes.