Antioxidant volatiles of the freshwater bryozoan Hyalinella punctata
Two volatile samples of the bryozoan Hyalinella punctata (seasonally collected from the same locality) were isolated (hydrodistillation, Clevenger apparatus), identified (GC and GC–MS) and screened in vitro (EPR) for anti-hydroxyl radical activity. The main components of sample 1 (2-ethyl-1-hexanol 37.00%, dodecanol 21.40% and hexanal 8.40%) and sample 2 (2-ethyl-1-hexanol 30.50%, 7-tridecanol 24.60% and 1-hexadecanol 11.80%) were relatively similar. However, more components were present in the sample 2 (17 and 25, respectively). EPR measurements indicated significant anti-hydroxyl radical activity of the both samples (75.00 ± 6.00% and 87.00 ± 8.00%, respectively) whereas the generation of other types of free radicals in reaction with hydroxyl radicals was not observed. According to the best of our knowledge, this is the first report of 31 organic compounds from the phylum Bryozoa. Alcohols, aldehydes, ketones, esters and ethers of lower molecular mass appear to be characteristic for the volatiles of these organisms commonly known as moss animals.