Optimization of fermentation conditions for sea lettuce (Ulva lactuca) and application effect of the fermented sea lettuce in sea cucumber (Apostichopus japonicus) culture
JIA Wenguang, LI Huili, PAN Xiaojing, ZHANG Hongxia, YU Zhen, LI Rui, XING Ronglian, CHEN Lihong
Optimization of fermentation conditions for sea lettuce (Ulva lactuca) and application effect of the fermented sea lettuce in sea cucumber (Apostichopus japonicus) culture
College of Life Sciences，Yantai University，Yantai 264005，China
{{custom_zuoZheDiZhi}}
{{custom_authorNodes}}
{{custom_bio.content}}
{{custom_bio.content}}
{{custom_authorNodes}}
Collapse
History+
Published
2024-08-14
Issue Date
2024-08-14
Abstract
To optimize the fermentation process of sea lettuce (Ulvalactuca) fermented diet and explore the effects of fermented sea lettuce diet on the growth and digestion of sea cucumber (Apostichopusjaponicus), the fermentation conditions of sea lettuce were optimized by single factor experiment including temperature (20, 25, 30, 35, and 40 ℃), moisture (30%, 40%, 50%, 60%, and 70%), and inoculation dose (1×106, 2×106, 3×106, 4×106, and 5×106 CFU/g (dry matter) )and response surface methodology with Bacillustequilensis as the fermentation agent and contents of reducing sugar, free amino acids and peptides in the fermentation products as the evaluation indices. Sea cucumber with body weight of (6. 48 g±0. 84 g) were reared in 9 plastic tanks of each 40 cm×30 cm×25 cm and fed fermented sea lettuce, unfermented sea lettuce dry powder and commercial diet for 30 days at water temperature of 15-17 ℃ and salinity of 25-35.The results showed that the best fermentation of the sea lettuce was observed under the optimal conditions of temperature of 33 ℃, inoculum quantity of 4.4×106 CFU/g and 50% water content, with increase in free amino acids from 3.6 mg/g to 45.0 mg/g, peptides from 30.1 mg/g to 96.0 mg/g, and reducing sugars from 1.3 mg/g to 20.8 mg/g for 7 days fermentation. Feeding trail showed that there was higher diet conversion efficiency and digestive enzyme activity in the sea cucumber fed the fermented sea lettuce diet than those fed the unfermented dry powder diet and commercial diet (P<0.05), without significant difference in the weight gain rate from that in commercial diet group (P>0.05), significantly higher than that in unfermented dry sea lettuce powder group (P<0.05) and without significant difference in the food ingesting rate of sea cucumber in the three groups (P>0.05). The findings indicate that fermented U.lactuca can replace commercial diet, improve the weight gain rate and digestive enzyme activity of sea cucumber, which provides wide range of raw material resources for sea cucumber diet.
JIA Wenguang, LI Huili, PAN Xiaojing, ZHANG Hongxia, YU Zhen, LI Rui, XING Ronglian, CHEN Lihong.
Optimization of fermentation conditions for sea lettuce (Ulva lactuca) and application effect of the fermented sea lettuce in sea cucumber (Apostichopus japonicus) culture[J]. Journal of Dalian Fisheries University, 2024, 39(3): 410-419 https://doi.org/10.16535/j.cnki.dlhyxb.2023-257
PDF(3647 KB)
