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The degradation of the green pigment chlorophyll in plants is known to yield phyllobilins as highly abundant linear tetrapyrroles. Recently, a split path of the degradation pathway has been discovered, leading to so-called dioxobilin-type (or type-II) phyllobilins. The first characterized type-II phyllobilin was colorless featuring four deconjugated pyrrole units. Similar to the type-I branch, for which yellow oxidation products of the colorless phyllobilins — the type-I phylloxanthobilins — are known, a type-II phylloxanthobilin has recently been characterized from senescent leaves of grapevine. Type-I phylloxanthobilins appear to be actively produced in the plant, are known to possess interesting chemical properties, and were shown to act as potent antioxidants that can protect cells from oxidative stress. Here we report the isolation and structural characterization of a type-II phylloxanthobilin from de-greened leaves of savoy cabbage, which turned out to be structurally closely related to bilirubin. Bilirubin is known to possess high antioxidative activity; in addition, savoy cabbage is considered to promote health benefits due to its high content in antioxidants. We therefore investigated the in vitro antioxidative potential of the newly identified type-II phylloxanthobilin using two different approaches, both of which revealed an even higher antioxidative activity for the type-II phylloxanthobilin from savoy cabbage compared to bilirubin.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…

The sun is the only source of renewable energy available to us, if geothermal energy is not taken into account. In the form of radiation (UV light, visible light, infrared light, Section 1.1) it sends us annually 178,000 terawatts (1 TW = 10¹² W; unit of power 1 W = 1 J s^–1 = 859.85 calories per hour), that is to say 15,000 times the energy consumed annually by humanity. Only 0.1% of the solar energy received by planet Earth is converted into plant biomass, i.e. 100 × 10⁹ tons per year which corresponds to ca. 180 × 10⁹ tons per year of CO₂ captured from the atmosphere. This CO₂ returns to the biosphere after the death of the plants. Consumption of fossil carbon emits ca. 35 × 10⁹ tons of CO₂ yearly. Biomass is the material produced by all living organisms (plants, animals, microorganisms, fungi)…

Radiative transfer algorithms in combination with empirical formulae have been the most popular approach to the analysis of ocean primary productivity from remotely sensed images of the Earth. These methods fully rely on the limited amounts of ground truth data available and assumptions regarding how sensor, Earth's surface and atmospheric properties influence the radiation captured in different ranges of the electromagnetic spectrum. As these assumptions are restraining, multi-spectral and fusion techniques based on the application of unsupervised neural networks can contribute to the improvement in ocean colour studies and enable analysis of complex water types. This chapter presents the application of a hierarchy of self-organizing feature maps to clustering and differentiation of oceanic waters. The practical studies are performed on imagery captured all over the Pacific Ocean by the Ocean Colour and Temperature Scanner on board the Japanese satellite ADEOS.

This study investigates the effect of copper on the germination and growth of watermelon plants. It was found that copper only inhibited the germination and growth of watermelon plants when its concentrations were high. Copper concentrations of either 50 or 100μM increased chlorophyll content in the plants slightly while copper concentrations over 100μM led to an obvious decrease in chlorophyll contents. It is concluded that excess copper significantly affects the germination and growth of watermelon.

To evaluate the toxic effects of environmental contaminant PFOA on green algae, Chlorella pyrenoidosa was exposed to a serial concentaertions of PFOA for proliferation evaluation and physiological status analysis. Within 96h, PFOA doses equal to or over 50 mg/L all inhibited the proliferation speed of Chlorella pyrenoidosa(p<0.05). The 96h- EC₅₀ value of PFOA was determined to be 261.2 mg/L. In a chronic experiment with 8 days of PFOA treatment, all of the treated groups showed decreased Chlorophyll a concentration. PFOA equal to or over 100 mg/L resulted in decreased antioxidant enzymes activity and increased MDA content in Chlorella pyrenoidosa(P<0.05).

The effects of oil water accommodated fraction (WAF), emulsion (DWAF) and dispersants on chlorophyll-a content, protein content and enzymatic activity and of Isochrysis galbana were studied by experimental ecology method with 96 hours. Thee results showed that content of protein and chlorophyll-a were decreased with the extension of time under the three stress. There were significant effects of three solutions on SOD, GSH-PX and MDA. After 96 hours, the lowest content of protein, chlorophyll-a, SOD and GSH-PX, the highest content of MDA were found in WAF group. Therefore WAF stress had the most influential effects on physiological and biochemical characteristics of Isochrysis galbana in the experiment.