Get access

Effects of antibiotics on hydrogen production and gut symbionts in the Formosan subterranean termite Coptotermes formosanus (Isoptera: Rhinotermitidae)

Authors

  • Yueqing Cao,

    1. College of Bioengineering, Chongqing University, Chongqing, China
    2. Coastal Research & Extension Center, Mississippi State University, Poplarville, MS, USA
    Search for more papers by this author
  • Jian-Zhong Sun,

    1. Coastal Research & Extension Center, Mississippi State University, Poplarville, MS, USA
    2. School of the Environment, Jiangsu University, Zhenjiang, Jiangsu Province, China
    Search for more papers by this author
  • Jose M. Rodriguez

    1. Mississippi State Chemical Laboratory, Petroleum Production Division, Mississippi State University, Starkville, MS, USA
    Search for more papers by this author

Jian-Zhong Sun, School of the Environment, Jiangsu University, Zhenjiang 212013, China. Tel: +86 511 88796122; fax: +86 511 88790955; email: jzsun1002@hotmail.com

Abstract

Abstract  Symbiotic microorganisms that inhabit the gut of Coptotermes formosanus enable this termite to degrade lignocelluloses and further produce hydrogen as an important intermediate to be recycled in its hindgut or as a byproduct to be emitted to the atmosphere. Both symbiotic protists and prokaryotes in the guts of termites demonstrated some different roles with respect to hydrogen production. In this study, the effects of two antibiotics, ampicillin and tetracycline, on hydrogen emission and the gut symbionts of C. formosanus were investigated. Hydrogen emission from termite guts was significantly enhanced when termites fed on wood diets treated with either ampicillin or tetracycline. The greatest H2 emission rates, 2 519 ± 74 and 2 080 ± 377 nmol/h/g body weight, were recorded with the treatments of ampicillin and tetracycline, respectively, which showed 6–7 times more H2 production than that of controls. Antibiotic-treated diets negatively affected the prokaryotic communities and reduced their abundances, particularly on those ectosymbionts inhabiting the gut walls or in the gut fluid of C. formosanus, such as spirochetes. However, no significant reductions in the counts of gut cellulolytic protists, Pseudotrichonympha grassii and Holomastigotoids hartmanni, were recorded; and with a further observation by confocal laser scanning microscopy, the endosymbionts inhabiting P. grassii generally survived the antibiotic treatments. These results suggest that some prokaryotes may serve as the main hydrogen consumers, while P. grassii, together with its endosymbionts, may function as the main contributors for hydrogen production in the hindgut of C. formosanus.

Get access to the full text of this article

Ancillary