不同低温时间无水保活对中国圆田螺存活、营养组成、消化酶活性及抗氧化指标的影响

Effects of different times of low temperature anhydrous preservation on survival,nutritional composition,enzyme activities and antioxidant indexes of Cipangopaludina chinensis

为改进中国圆田螺保存技术,促进螺蛳粉产业可持续发展。本研究利用初始体重为(21.71±2.70)g的健康中国圆田螺1500只,探讨了低温(4℃)无水条件下0、14、28、42和56 d等不同时间中国圆田螺存活、形体指标、一般营养组成、脂肪酸、消化酶活性和抗氧化指标的变化。结果显示,4℃短期存放(14~28 d)中国圆田螺的存活率均超过93%,但是超过42 d后,存活率降至78%以下。低温28和42 d的肝重和肝体比均显著高于对照组,与对照组相比,低温56 d体重降了7.6%,而肝重显著提高。营养成分结果显示,各组间肌肉的粗蛋白、粗灰分和水分均无显著影响。而粗脂肪含量呈现上升趋势,其中28、42和56 d的粗脂肪含量显著高于对照组。糖原含量总体呈上升趋势,其中14与56 d差异显著。脂肪酸结果显示,SFA和MUFA含量总体均呈下降趋势,28~56 d均显著低于对照和14 d组;28和42 d的PUFA含量显著高于其他处理组。本研究中所有消化酶和抗氧化酶活性总体均呈现下降趋势。对照组的淀粉酶活性显著低于14 d,但显著高于42 d。除42 d的胰蛋白酶外,其余处理的脂肪酶和胰蛋白酶含量显著低于对照组。42 d的谷胱甘肽过氧化氢酶显著低于其他各组,且42 d的超氧化物歧化酶、过氧化氢酶活性和丙二醛含量也均显著低于对照组。研究表明,在4℃条件下无水保活超过42 d会导致中国圆田螺出现较高的死亡率,由于42 d后体内的消化酶和抗氧化酶活性降低,内环境平衡被打破,进而导致高的死亡率。胁迫期间中国圆田螺主要以蛋白质作为能量来源,其次是大量的饱和脂肪酸与单不饱和脂肪酸作为能量物质被消耗,而多不饱和脂肪酸被更好地保留下来。本研究为了解中国圆田螺在低温无水保活不同时间下的生理生化适应对策及改善其储存运输管理提供科学依据。

Cipangopaludina chinensis is an economically important aquatic snail with high medicinal value in China.To improve the technology of preserving C.chinensis and to promote the sustainable development of the snails rice noodle industry,in this study,1,500 healthy C.chinensis with an initial body mass of(21.71±2.70)g were used to investigate the effects of survival,morphological indices,nutritional composition,fatty acids,digestive enzyme activity and antioxidant indices of storing snails for 0,14,28,42 and 56 d under 4℃ anhydrous conditions.The results showed that the survival rate of snails stored at 4℃ for a short period of time(14-28 d)exceeded 93%,but after 42 days,the value fell below 78%.The liver weight and liver/body ratio of 28 and 42 d of hypothermia were significantly higher than those of the control.Compared with the control,body mass decreased by 7.6%at 56 d of hypothermia,while liver weight was markedly increased.The results of nutritional composition examination showed no difference in crude protein,crude ash and moisture of muscle between the groups,and the crude fat content showed an increasing trend,with 28,42 and 56 d being considerably higher than the control.The glycogen content showed an overall upward trend,among which the difference between 14 and 56 d was significant.Fatty acid detection revealed that the contents of SFA and MUFA showed an overall downward trend,with 28-56 d dramatically lower than those of the control and 14 d.The PUFA contents at 28 and 42 d were notably higher than the other treatments.All digestive and antioxidant enzyme activities in this study showed an overall decreasing trend.The amylase activity of the control was significantly lower than that in 14 d,but remarkably higher than that in 42 d.Then,except for the 42 d trypsin,the lipase and trypsin content of the other treatments was substantially less than that of the control.The glutathione catalase of the 42 d group was significantly lower than that of the other groups,and the activities of superoxide dismutase,catalase and malondialdehyde at 42 d were dramatically lower than those of the control.In summary,it is shown that anhydrous preservation for more than 42 days at 4℃ will lead to a higher mortality rate of C.chinensis.After 42 d,the digestive enzyme and antioxidant enzyme activities in the body are reduced,and the internal environmental balance is disrupted,which in turn led to high mortality.During the stress period,C.chinensis mainly use protein as an energy source,and then a large amount of saturated fatty acids and monounsaturated fatty acids are consumed as energy materials,while polyunsaturated fatty acids are better retained.This study provides a scientific basis for understanding the physiological and biochemical adaptation countermeasures of snails under different times of low-temperature anhydrous preservation and improving their storage and transportation management.