Gut pH, redox conditions and oxygen levels in an aquatic caterpillar: potential effects on the fate of ingested tannins.
نویسندگان
چکیده
Larvae of the freshwater moth Acentria ephemerella (Pyralidae, Lepidoptera) can fully develop on Myriophyllum spicatum, a submerged macrophyte containing 7-10% of its dry mass as tannins. We investigated the physicochemical gut parameters of larvae fed with M. spicatum or Potamogeton perfoliatus, a food plant lacking tannins, and the chemical fate of ingested polyphenols. Microelectrode studies revealed that larval midguts were slightly alkaline (pH 8) and had a positive redox potential. Whole guts were oxygen sinks owing to the oxygen demand of the gut contents. Oxygen penetrated the midgut up to 100 microm, but the centres of the foregut and midgut were always anoxic. The physicochemical parameters of the guts did not change with the food plant. The major tannin from M. spicatum, tellimagrandin II, was significantly depleted in the midgut and was not detected in faeces. In vitro studies indicated that tellimagrandin II is rapidly depleted mainly through oxidation, and hydrolysis might also occur. Our findings for A. ephemerella are compared with those for terrestrial Lepidoptera, and possible mechanisms for adaptations to tannin-rich food plants are discussed.
منابع مشابه
Roles of peritrophic membranes in protecting herbivorous insects from ingested plant allelochemicals.
Four mechanisms by which peritrophic membranes (PMs) potentially protect herbivorous insects from ingested allelochemicals are reviewed: adsorption, ultrafiltration, polyanion exclusion, and the capacity of PMs to act as antioxidants. Most of the research on the protective roles of PMs against ingested allelochemicals has focused on their impermeability to tannins. Adsorption of tannins by the ...
متن کاملCollectorless flotation of Chalcocite by controlling redox potential
Using microflotation method, this study explored the collectorless flotation of Chalcocite and its dependence on the redox potential of pulp . Electrochemical studies were performed by cyclic voltammetry in specific potential ranges and at different pH values. The results show that significant floatability of Chalcocite occurs in the specific reducing conditions. By increasing potentials, on t...
متن کاملImpact of Multi-metal Mixture Administration Through Drinking Water on the Gut Bacterial Microflora and Oxidative Stress Parameters in Male and Female Mice
Background: Heavy metal containing wastes reaches to the food chain either directly or indirectly. These ingested toxic elements manifest direct impact on the gut ecosystem and its overall functioning. The present study explores the alteration in mice gut bacteria on exposure to mixture of toxic heavy metals through drinking water. Methods: Twelve experimental groups of Swiss albino male and ...
متن کاملEffects of environmental factors on species diversity of rotifers using biodiversity indicators and canonical correlation analysis (CCA)
Rotifers are microscopic aquatic animals of phylum Rotifera, live in a diverse range of aquatic habitats. They are important in ecology of freshwater ecosystems by recycling nutrients and can alter trophic dynamic of planktonic communities. These features have also been used to infer environmental conditions in an aquatic habitat. Because of the important roles of this group of animals in the t...
متن کاملThe Therapeutic Effect of Exercise on Anxiety and Bowel Oxidative Stress in the Maternal Separation Animal Model
Introduction: According to evidence, Early-Life Stress (ELS), mood disorders, and medical comorbidities, i.e. Irritable Bowel Syndrome (IBS), are correlated; however, the direct contribution of ELS to IBS manifestations is less understood. The current study aimed at evaluating the effect of voluntary exercise on the mitochondrial dysfunction of the bowel fibroblasts, following the confirmation...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of insect physiology
دوره 54 2 شماره
صفحات -
تاریخ انتشار 2008