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Gynura bicolor (Roxb. & Willd.) DC is widely distributed in certain areas of Asia and is very popular in vegetarian cuisine in Taiwan. To investigate the regulatory roles of G. bicolor in various functions in crustaceans, we examined innate non-specific immune responses (including total hemocyte count (THC), phenoloxidase activity (PO), respiratory bursts (RBs), and superoxide dismutase (SOD) activity), physiological responses (including haemolymph glucose, lactate, and lipids), and gene expressions (including prophenoloxidase (proPO), lipopolysaccharide- and b-1,3-glucan-binding protein (LGBP), and peroxinectin (PE) mRNA transcripts) to the pathogen Vibrio alginolyticus in white shrimp (Litopenaeus vannamei) that were individually injected with the water extract from G. bicolor at 2, 4, and 8 μg g(-1). Results indicated that PO, RBs, SOD activity, proPO, LGBP, and PE mRNA transcripts of shrimps receiving the water extract of G. bicolor at 2, 4, and 8 μg g(-1) significantly increased after challenge with V. alginolyticus for 96 h. However, no significant difference in the THC was seen at any dose. L. vannamei injected with the water extract of G. bicolor at all doses respectively maintained lower glucose, lactate, and lipid levels in response to V. alginolyticus challenge at 12-36, 24-36, and 24-48 h. Survival rates at 24-72 h of L. vannamei that received G. bicolor at any dose was significantly higher than those of shrimp that received saline. It was concluded that the water extract of G. bicolor can maintain physiological homeostasis and enhance immunity against V. alginolyticus infection in L. vannamei., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Zingerone, one of the active components of ginger, is a phenolic alkanone with antioxidant and anti-inflammatory properties. The effects of zingerone supplementation on the growth, immunity, and disease resistance of Pacific white shrimp (Litopenaeus vannamei) juveniles were studied. Four experimental diets, including a control diet (without zingerone enrichment) and 1, 2.5, and 5 mg zingerone (kg diet)(-1) were used. After 56 days of culture, shrimp fed diets supplemented with 1, 2.5, and 5 mg zingerone (kg diet)(-1) had significantly greater weight gain and feed efficiency than the controls. Furthermore, after 56 days of culture, shrimp fed all doses of the zingerone diet had higher survival rates compared to the controls after 24-72 h of challenge by the pathogen, Vibrio alginolyticus. Significantly increased phenoloxidase levels were found in shrimp fed the zingerone diets at all doses, and respiratory bursts, lysozyme and phagocytic activities of shrimp fed 2.5 and 5 mg zingerone (kg diet)(-1) also significantly increased. Neither the total hemocyte count nor superoxide dismutase activity of the experimental and control groups revealed significant differences at any dose. The results indicate that zingerone can be recommended as a supplement to shrimp feed to increase growth, immunity, and disease resistance against the pathogen, V. alginolyticus. Use of zingerone as appetizer and immunostimulant in shrimp is promising., (Copyright © 2011 Elsevier Ltd. All rights reserved.)