biostudies-literatureCharras QSwedish Foundation for Strategic Research SSF38https://www.ebi.ac.uk/biostudies/studies/S-EPMC10929114biostudies-literatureUnknown20(1)<h4>Background</h4>The extraction of thylakoids is an essential step in studying the structure of photosynthetic complexes and several other aspects of the photosynthetic process in plants. Conventional protocols have been developed for selected land plants grown in controlled conditions. Plants accumulate defensive chemical compounds such as polyphenols to cope with environmental stresses. When the polyphenol levels are high, their oxidation and cross-linking properties prevent thylakoid extraction.<h4>Results</h4>In this study, we developed a method to counteract the hindering effects of polyphenols by modifying the grinding buffer with the addition of both vitamin C (VitC) and polyethylene glycol (PEG4000). This protocol was first applied to the marine plant Posidonia oceanica and then Plant methodsAn efficient protocol for extracting thylakoid membranes and total leaf proteins from Posidonia oceanica and other polyphenol-rich plants.PMC10929114ARC19-0051Guillemain DDourguin FLaganier HCharras QRey PCaffarri SJungas CMolinie RIsmael MPeschoux SRayon CfalseAn efficient protocol for extracting thylakoid membranes and total leaf proteins from Posidonia oceanica and other polyphenol-rich plants.<h4>Background</h4>The extraction of thylakoids is an essential step in studying the structure of photosynthetic complexes and several other aspects of the photosynthetic process in plants. Conventional protocols have been developed for selected land plants grown in controlled conditions. Plants accumulate defensive chemical compounds such as polyphenols to cope with environmental stresses. When the polyphenol levels are high, their oxidation and cross-linking properties prevent thylakoid extraction.<h4>Results</h4>In this study, we developed a method to counteract the hindering effects of polyphenols by modifying the grinding buffer with the addition of both vitamin C (VitC) and polyethylene glycol (PEG4000). This protocol was first applied to the marine plant Posidonia oceanica and then 2024-01-01T00:00:00Z2024 Mar2026-07-14T23:50:42.907Z2026-06-26T03:22:02.333ZS-EPMC109291143846832810.1186/s13007-024-01166-7