Academic Journal

Cyanobacterial toxins and cyanopeptide transformation kinetics by singlet oxygen and pH-dependence in sunlit surface waters

التفاصيل البيبلوغرافية
العنوان: Cyanobacterial toxins and cyanopeptide transformation kinetics by singlet oxygen and pH-dependence in sunlit surface waters
المؤلفون: Natumi, Regiane, Dieziger, Christoph, Janssen, Elisabeth M.-L.
بيانات النشر: American Chemical Society
سنة النشر: 2021
مصطلحات موضوعية: cyanopeptide, cyanobacteria, microcystin, phototransformation, anabaenopeptin, natural toxins, tyrosine, singlet oxygen
الوصف: To assess the risks associated with cyanobacterial blooms, the persistence and fate processes of cyanotoxins and other bioactive cyanobacterial metabolites need to be evaluated. Here, we investigated the reaction with photochemically produced singlet oxygen ( 1 O 2 ) for 30 cyanopeptides synthesized by Dolichospermum flos aquae , including 9 anabaenopeptins, 18 microcystins, 2 cyanopeptolins, and 1 cyclamide. All compounds were stable in UVA light alone but in the presence of a photosensitizer we observed compound-specific degradation. A strong pH effect on the decay was observed for 18 cyanopeptides that all contained tyrosine or structurally related moieties. We can attribute this effect to the reaction with 1 O 2 and triplet sensitizer that preferentially react with the deprotonated form of tyrosine moieties. The contribution of 1 O 2 to indirect phototransformation ranged from 12 to 39% and second-order rate constants for 9 tyrosine-containing cyanopeptides were assessed. Including the pH dependence of the reaction and system-independent second-order rate constants with 1 O 2 will improve the estimation of half-lives for multiclass cyanopeptide in surface waters. Our data further indicates that naturally occurring triplet sensitizers are likely to oxidize deprotonated tyrosine moieties of cyanopeptides and the specific reactivity and its pH dependence needs to be investigated in future studies.
نوع الوثيقة: article in journal/newspaper
اللغة: English
تدمد: 0013-936X
Relation: Environmental Science and Technology--Environ. Sci. Technol.--journals:872--0013-936X--1520-5851; eawag:23739; journal id: journals:872; e-issn: 1520-5851; ut: 000721255600022; scopus: 2-s2.0-85118770238; pmid: 34714625
DOI: 10.1021/acs.est.1c04194
الاتاحة: https://doi.org/10.1021/acs.est.1c04194
رقم الانضمام: edsbas.56CCE349
قاعدة البيانات: BASE
الوصف
تدمد:0013936X
DOI:10.1021/acs.est.1c04194