6alpha,7beta-Dihydroxyvouacapan-17beta-oic acid (1) was isolated from Pterodon polygalaeflorus Benth. Modification of 1 yielded 6alpha-hydroxyvouacapan-7beta,17beta-lactone (2) and then 6-oxovouacapan-7beta,17beta-lactone (3). Photosynthesis inhibition by 3 was evaluated in spinach chloroplasts. The uncoupled non-cyclic electron transport rate and ATP synthesis were inhibited by 3, which behave...

The changes of Chl a fluorescence induction curve in response to different salinity levels in Canola (Barassica napus, L.) plants were investigated. The canola seedlings were exposed to salt stress (100 mM and 200 mM NaCl) for 7 days and Chl a fluorescence induction kinetics was analysed. By using the OJIP-test, various parameters like VJ, area, N, φPo, φEo, ψo, RC/ABS and PIABS were calculated...

Biochemical and functional changes in photosystem II (PSII) were investigated during natural senescence of maple (Acer platanoides L.) leaves. Three different types of senescing leaves were used: early senescent green (G), yellow green (YG) and yellow (Y). The main goal of this study was to investigate the dynamics of degradation of major photosynthetic proteins (D1, LHCII and Rubisco LSU) and ...

The changes in PSII photochemistry in Spirulina platensis cells exposed to salinity stress (0-0.8 M NaCl) for 12 h were studied. Salinity stress induced a decrease in oxygen evolution activity, which correlated with the decrease in the quantum yield of PSII electron transport (PhiPSII). Phycocyanin content decreased significantly while chlorophyll content remained unchanged in salt-stressed cel...

To investigate the effects of high-temperature stress on chlorophyll fluorescence induction kinetics peony and to determine indicators for rapid screening varieties responding high temperatures, three four-year-old variety, ‘Fengdanbai’, ‘Huhong’, ‘Yinhongqiaodui’, were selected as materials. The photosynthetic curves (Pn-PAR) fast (OJIP curves) leaves measured at different times under conditio...

Bermudagrass is widely utilized in parks, lawns, and golf courses. However, cold is a key factor limiting resource use in bermudagrass. Therefore, it is meaningful to study the mechanism of bermudagrass response to cold. Nitric oxide (NO) is a crucial signal molecule with multiple biological functions. Thus, the objective of this study was to investigate whether NO play roles in bermudagrass re...