{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,28]],"date-time":"2026-06-28T10:39:06Z","timestamp":1782643146102,"version":"3.54.5"},"reference-count":31,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,4,29]],"date-time":"2022-04-29T00:00:00Z","timestamp":1651190400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003336","name":"Bulgarian National Science Fund","doi-asserted-by":"publisher","award":["KP-06-H29\/11"],"award-info":[{"award-number":["KP-06-H29\/11"]}],"id":[{"id":"10.13039\/501100003336","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["CIMB"],"abstract":"<jats:p>Antimicrobial photodynamic therapy (aPDT) has been considered as a promising methodology to fight the multidrug resistance of pathogenic bacteria. The procedure involves a photoactive compound (photosensitizer), the red or near infrared spectrum for its activation, and an oxygen environment. In general, reactive oxygen species are toxic to biomolecules which feature a mechanism of photodynamic action. The present study evaluates two clinical isolates of Gram-negative Flavobacteriumhydatis (F. hydatis): a multidrug resistant (R) and a sensitive (S) strain. Both occur in farmed fish, leading to the big production losses because of the inefficacy of antibiotics. Palladium phthalocyanines (PdPcs) with methylpyridiloxy groups linked peripherally (pPdPc) or non-peripherally (nPdPc) were studied with full photodynamic inactivation for 5.0 \u00b5M nPdPc toward both F. hydatis, R and S strains (6 log), but with a half of this value (3 log) for 5.0 \u00b5M pPdPc and only for F. hydatis, S. In addition to the newly synthesized PdPcs as a \u201cpositive control\u201d was applied a well-known highly effective zinc phthalocyanine (ZnPcMe). ZnPcMe showed optimal photocytotoxicity for inactivation of both F. hydatis R and S. The present study is encouraging for a further development of aPDT with phthalocyanines as an alternative method to antibiotic medication to keep under control the harmful pathogens in aquacultures\u2019 farms.<\/jats:p>","DOI":"10.3390\/cimb44050133","type":"journal-article","created":{"date-parts":[[2022,4,29]],"date-time":"2022-04-29T16:49:57Z","timestamp":1651250997000},"page":"1950-1959","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Palladium Phthalocyanines Varying in Substituents Position for Photodynamic Inactivation of Flavobacterium hydatis as Sensitive and Resistant Species"],"prefix":"10.3390","volume":"44","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7841-0910","authenticated-orcid":false,"given":"Vanya","family":"Mantareva","sequence":"first","affiliation":[{"name":"Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vesselin","family":"Kussovski","sequence":"additional","affiliation":[{"name":"The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petya","family":"Orozova","sequence":"additional","affiliation":[{"name":"National Reference Laboratory for Fish, Mollusks and Crustacean Diseases, National Diagnostic Research Veterinary Institute, 1000 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Angelov","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahmut","family":"Durmu\u015f","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Gebze Technical University, Gebze 41400, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3221-2545","authenticated-orcid":false,"given":"Hristo","family":"Najdenski","sequence":"additional","affiliation":[{"name":"The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"735268","DOI":"10.1016\/j.aquaculture.2020.735268","article-title":"Effects of reduced organic matter loading through membrane filtration on the microbial community dynamics in recirculating aquaculture systems (RAS) with Atlantic salmon parr (Salmo salar)","volume":"524","author":"Fossmark","year":"2020","journal-title":"Aquaculture"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.aquaculture.2017.09.046","article-title":"Blue light-emitting diode photoinactivation inhibits edwardsiellosis in fancy carp (Cyprinus carpio)","volume":"483","author":"Roh","year":"2018","journal-title":"Aquaculture"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Y\u00fafera, M. 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