Dietary Transfer of Heavy Metals in Manatees

In recent decades, manatees and dugongs globally have exhibited potentially detrimental levels of a variety of heavy metals in their body tissues. The threatened Florida manatee (Trichechus manatus latirostris), which is a subspecies of the West Indian manatee (Trichechus manatus), has shown corresponding high levels of heavy metals in their blood, skin, liver, and kidneys. As obligate herbivores, these animals rely heavily upon seagrasses as a major component of their diet. Globally, seagrasses at low latitudes have high levels of heavy metals in their tissues. Detrimental levels of heavy metals in Sirenians have not been established until now. This study is assessing the heavy metal concentrations of seagrasses in South Florida as a major dietary contributor to manatees, and investigating possible sources of these metals

Starch, Lipid, and Protein Accumulation in Nutrient-Stressed Microalgal Cells Studied Using Fourier Transform Infrared Microscopy

Microalgae are fast growing organisms that can be used as feedstock for the production of biofuels. The metabolism of microalgae can be manipulated by exposing them to different environmental conditions for favoring the accumulation of lipids, carbohydrates or proteins. For example, a change in growth conditions can cause the accumulation of large amounts of lipids, representing an opportunity for biodiesel production. Monitoring changes in the composition of microalgal cells is therefore important in assessing new growth conditions. However, at present, most techniques are time consuming, invasive and expensive. Here we have used FTIR microscopy to quantify lipid, protein, and starch accumulation in Neochloris minuta cells grown in the presence and absence of nitrogen. Under nitrogen deprivation the cellular lipid composition increases by a factor of 2.4, the cellular protein concentration decreases by ~60% while the starch concentration is unaltered. These estimates of biochemical composition were derived using a variety of analytical methods, and form the basis for establishing to what extent FTIR microscopy can be used as a probe of cellular biochemical composition. We find that the distribution of materials in Neochloris minuta cells estimated directly from the FTIR spectra compare favorably with that estimated using these other analytical methods. FTIR spectroscopy is shown to be a versatile and easy-to-use tool for estimating distributions of biological materials in microalgal cells

Temporal Baseline of Essential and Non-essential Elements Recorded in Baleen of Western Arctic Bowhead Whale (Balaena mysticetus)

This study established the first baseline of changing elemental concentrations in bowhead whale baleen over time (1958–1999). From previously published stable isotope data, year, season (summer or winter), and location (Beaufort or Bering/Chukchi seas) were attributed to each sample. Thirteen elements (Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, Zn) in baleen from nine subsistence-harvested bowhead whales (n = 138) were detected. Al, Cu, and Fe were the highest concentrations while Cd and V were among the lowest. Our data supports absorption as the main route of exposure to environmental elements rather than biomagnification due to bowhead whales’ low trophic position. A linear mixed-effects model confirmed most elements’ concentrations increased with time, while location and sex were insignificant explanatory factors. These temporal fluctuations were most likely a product of environmental changes due to a warming climate and human activities

Synthesis and Incorporation of Photoactive Chlorin-Heme Dimers into Proteins

Paper id 1259

Chapter 5: Artificial Photosynthesis Ruthenium Complexes

This technical book explores current and future applications of solar power as an unlimited source of energy that earth receives every day. Photosynthetic organisms have learned to utilize this abundant source of energy by converting it into high-energy biochemical compounds. Inspired by the efficient conversion of solar energy into an electron flow, attempts have been made to construct artificial photosynthetic systems capable of establishing a charge separation state for generating electricity or driving chemical reactions. Another important aspect of photosynthesis is the CO2 fixation and the production of high energy compounds. Photosynthesis can produce biomass using solar energy while reducing the CO2 level in air. Biomass can be converted into biofuels such as biodiesel and bioethanol. Under certain conditions, photosynthetic organisms can also produce hydrogen gas which is one of the cleanest sources of energy.https://nsuworks.nova.edu/cnso_chemphys_facbooks/1005/thumbnail.jp