Chlorophyll fluorescence-based method shows great potentials for on-site assessing the vitality of algae in treated ship's ballast water. However, there is very limited information on the mechanism of chlorophyll fluorescence in photosystem II (PSII) after the NaClO treatment. In this paper, the effects of NaClO treatments with five concentrations (0.01, 0.04, 0.08, 0.12 and 0.15 mg/L) and treating periods (6, 24 and 48 h) on the chlorophyll fluorescence kinetics and spectra of Chlorella vulgaris (C. vulgaris) and Platymonas helgolandica (P. helgolandica) were investigated. Experimental results showed that both exposure time and dose were important factors that affect the toxicity of NaClO to microalgae. Further analyses showed that the maximum photochemical quantum yield of PSII, photochemical quenching and yield decreased rapidly with the increase in NaClO concentrations in the range of 0.04 mg/L to 0.15 mg/L, suggesting that NaClO seriously inhibited PSII reaction centers of algae. In addition, the maxima value of fluorescence at excitation wavelength still appeared near 437 nm and 468 nm under NaClO stress, pointing to the pigments for fluorescence produced by algae were mainly chlorophyll a and chlorophyll b antenna. As compared to chlorophyll a, the relative fluorescence intensity of chlorophyll b decreased significantly in the all of NaClO treatments. According to the fluorescence emission spectra, treatment of NaClO resulted in a shift of the maximum peak of C. vulgaris and P. helgolandica from 685.2 nm to 681.9 nm and 685.2 nm to 680.5 within 6 h, respectively. This indicates that the structure of antenna light-absorbing pigments of PSII changed under NaClO stress. These results revealed that the chlorophyll fluorescence mechanism in PSII of damaged microalgae occurred variation, which was important for the reliable application of on-site analysis of ballast water indicator based on chlorophyll fluorescence detection.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.scitotenv.2022.155192 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Impact of exogenous rhamnolipids on plant photosynthesis and biochemical parameters under prolonged heat stress.
Photosynthetica
January 2025
University of Reims Champagne-Ardenne, INRAE, RIBP, USC 1488, 51100 Reims, France.
High temperatures severely affect plant growth and development leading to major yield losses. These temperatures are expected to increase further due to global warming, with longer and more frequent heat waves. Rhamnolipids (RLs) are known to protect several plants against various pathogens.
View Article and Find Full Text PDFHonoring Hartmut Karl Lichtenthaler, innovative pioneer of photosynthesis, on his 90 birthday.
Photosynthetica
January 2025
Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, 94720 California, USA.
We honor Professor Hartmut Karl Lichtenthaler, a versatile pioneer of photosynthesis research, plant physiology, isoprenoid biochemistry, and stress physiology of plants, for his groundbreaking and creative contributions to plant science. His innovative research on the chemical composition, ultrastructure, and function of chloroplasts and his detection of the major methylerythritol 4-phosphate (MEP) isoprenoid biosynthetic pathway in plants is key to our current understanding of the physiology and biochemistry of photosynthesis systems. His ingenious use of the powerful laser-induced chlorophyll fluorescence imaging has helped us better understand the stress response processes in plant leaves.
View Article and Find Full Text PDFAssessment of salicylic acid and potassium nitrate to mitigate frost stress in autumn-sown potato crop cv. Sutlej.
Sci Rep
January 2025
Department of Agronomy, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan.
Potato is cultivated all the year round in Pakistan. However, the major crop is the autumn crop which is planted in mid-October and contributes 80-85% of the total production. The abrupt climate change has affected the weather patterns all over the world, resulting in the reduction of the mean air temperature in autumn by almost 1.
View Article and Find Full Text PDFMind the leaf anatomy while taking ground truth with portable chlorophyll meters.
Sci Rep
January 2025
Department of Plant Experimental Biology, Faculty of Science, Charles University, Viničná 5, 12800, Prague, Czech Republic.
A wide range of portable chlorophyll meters are increasingly being used to measure leaf chlorophyll content as an indicator of plant performance, providing reference data for remote sensing studies. We tested the effect of leaf anatomy on the relationship between optical assessments of chlorophyll (Chl) against biochemically determined Chl content as a reference. Optical Chl assessments included measurements taken by four chlorophyll meters: three transmittance-based (SPAD-502, Dualex-4 Scientific, and MultispeQ 2.
View Article and Find Full Text PDFNovel multiparameter optical sensor head design for marine environments.
Talanta
January 2025
DCU Water Institute, School of Chemical Sciences, Dublin City University, Ireland. Electronic address:
Anthropogenic activities have led to increased stress on our marine and other aquatic environments. There is a pressing need to monitor, measure, understand and mitigate causes of these pressures. This paper presents a novel optical head for monitoring and measuring marine based optical phenomena.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!