Shell mineralogy of a foundational marine species, Mytilus californianus, over half a century in a changing ocean.

Anthropogenic warming and ocean acidification are predicted to negatively affect marine calcifiers. While negative effects of these stressors on physiology and shell calcification have been documented in many species, their effects on shell mineralogical composition remains poorly known, especially over longer time periods. Here, we quantify changes in the shell mineralogy of a foundation species, Mytilus californianus, under 60 y of ocean warming and acidification. Using historical data as a baseline and a resampling of present-day populations, we document a substantial increase in shell calcite and decrease in aragonite. These results indicate that ocean pH and saturation state, not temperature or salinity, play a strong role in mediating the shell mineralogy of this species and reveal long-term changes in this trait under ocean acidification.

Applications of isothermal titration calorimetry in pure and applied research from 2016 to 2020.

The last 5 years have seen a series of advances in the application of isothermal titration microcalorimetry (ITC) and interpretation of ITC data. ITC has played an invaluable role in understanding multiprotein complex formation including proteolysis-targeting chimeras (PROTACS), and mitochondrial autophagy receptor Nix interaction with LC3 and GABARAP. It has also helped elucidate complex allosteric communication in protein complexes like trp RNA-binding attenuation protein (TRAP) complex. Advances in kinetics analysis have enabled the calculation of kinetic rate constants from pre-existing ITC data sets. Diverse strategies have also been developed to study enzyme kinetics and enzyme-inhibitor interactions. ITC has also been applied to study small molecule solvent and solute interactions involved in extraction, separation, and purification applications including liquid-liquid separation and extractive distillation. Diverse applications of ITC have been developed from the analysis of protein instability at different temperatures, determination of enzyme kinetics in suspensions of living cells to the adsorption of uremic toxins from aqueous streams.

A review of dielectrophoretic separation and classification of non-biological particles.

Dielectrophoresis (DEP) is a selective electrokinetic particle manipulation technology that is applied for almost 100 years and currently finds most applications in biomedical research using microfluidic devices operating at moderate to low throughput. This paper reviews DEP separators capable of high-throughput operation and research addressing separation and analysis of non-biological particle systems. Apart from discussing particle polarization mechanisms, this review summarizes the early applications of DEP for dielectric sorting of minerals and lists contemporary applications in solid/liquid, liquid/liquid, and solid/air separation, for example, DEP filtration or airborne fiber length classification; the review also summarizes developments in DEP fouling suppression, gives a brief overview of electrocoalescence and addresses current problems in high-throughput DEP separation. We aim to provide inspiration for DEP application schemes outside of the biomedical sector, for example, for the recovery of precious metal from scrap or for extraction of metal from low-grade ore.

Chemical Composition and Potential Practical Application of 15 Red Algal Species from the White Sea Coast (the Arctic Ocean).

Though numerous valuable compounds from red algae already experience high demand in medicine, nutrition, and different branches of industry, these organisms are still recognized as an underexploited resource. This study provides a comprehensive characterization of the chemical composition of 15 Arctic red algal species from the perspective of their practical relevance in medicine and the food industry. We show that several virtually unstudied species may be regarded as promising sources of different valuable metabolites and minerals. Thus, several filamentous ceramialean algae (Ceramium virgatum, Polysiphonia stricta, Savoiea arctica) had total protein content of 20-32% of dry weight, which is comparable to or higher than that of already commercially exploited species (Palmaria palmata, Porphyra sp.). Moreover, ceramialean algae contained high amounts of pigments, macronutrients, and ascorbic acid. Euthora cristata (Gigartinales) accumulated free essential amino acids, taurine, pantothenic acid, and floridoside. Thalli of P. palmata and C. virgatum contained the highest amounts of the nonproteinogenic amino acid ß-alanine (9.1 and 3.2 µM g-1 DW, respectively). Several red algae tend to accumulate heavy metals; although this may limit their application in the food industry, it makes them promising candidates for phytoremediation or the use as bioindicators.

Progress in Modern Marine Biomaterials Research.

The growing demand for new, sophisticated, multifunctional materials has brought natural structural composites into focus, since they underwent a substantial optimization during long evolutionary selection pressure and adaptation processes. Marine biological materials are the most important sources of both inspiration for biomimetics and of raw materials for practical applications in technology and biomedicine. The use of marine natural products as multifunctional biomaterials is currently undergoing a renaissance in the modern materials science. The diversity of marine biomaterials, their forms and fields of application are highlighted in this review. We will discuss the challenges, solutions, and future directions of modern marine biomaterialogy using a thorough analysis of scientific sources over the past ten years.

Positive Impact of Pulsed Electric Field on Lactic Acid Removal, Demineralization and Membrane Scaling during Acid Whey Electrodialysis.

The drying of acid whey is hindered by its high mineral and organic acid contents, and their removal is performed industrially through expensive and environmentally impacting serial processes. Previous works demonstrated the ability to remove these elements by electrodialysis alone but with a major concern-membrane scaling. In this study, two conditions of pulsed electric field (PEF) were tested and compared to conventional DC current condition to evaluate the potential of PEF to mitigate membrane scaling and to affect lactic acid and salt removals. The application of a PEF 25 s/25 s pulse/pause combination at an initial under-limiting current density allowed for decreasing the amount of scaling, the final system electrical resistance by 32%, and the relative energy consumption up to 33%. The use of pulsed current also enabled better lactic acid removal than the DC condition by 10% and 16% for PEF 50 s/10 s and 25 s/25 s, respectively. These results would be due to two mechanisms: (1) the mitigation of concentration polarization phenomenon and (2) the rinsing of the membranes during the pause periods. To the best of our knowledge, this was the first time that PEF current conditions were used on acid whey to both demineralize and deacidify it.

Effects of Seasonal Variability on the Physicochemical, Biochemical, and Nutritional Composition of Western Peninsular Malaysia Gracilaria manilaensis.

This study evaluated the effect of seasonal variation on the physicochemical, biochemical, and nutritional composition of Gracilaria manilaensis. Sampling was designed during the main monsoon seasons in Malaysia-the Southwest monsoon (SWM) and Northeast monsoon (NEM)-to understand the intraspecific variation (p < 0.05). Carbohydrates, protein, and dietary fiber were found to be higher in NEM-G. manilaensis, whereas a higher ash content was quantified in SWM-G. manilaensis. No significant differences were found in crude lipid and moisture content (p > 0.05). Vitamin B2 was calculated as (0.29 ± 0.06 mg 100 g-1) and (0.38 ± 0.06 mg 100 g-1) for the NEM and SWM samples, respectively (p < 0.05). The fatty acid profile showed the dominance of saturated fatty acids (SFAs)-palmitic acids, stearic acid, and myristic acid-while the mineral contents were found to be good sources of calcium (1750.97-4047.74 mg 100 g-1) and iron (1512.55-1346.05 mg 100 g-1). Tryptophan and lysine were recorded as the limiting essential amino acids (EAAs) in NEM G. manilaensis, while leucine and phenylalanine were found to be the limiting EAAs in the SWM samples. None of the extracts exhibited antibacterial properties against the screened strains. The study concluded that seasonal changes have a great effect on the biochemical composition of G. manilaensis.

Mineral Content of Various Portuguese Breads: Characterization, Dietary Intake, and Discriminant Analysis.

The chemical composition and daily mineral intake (DMI) of six macro (calcium, magnesium, sodium, potassium, phosphorous, and chloride) and four microminerals (copper, iron, manganese, and zinc) were determined in four types of Portuguese breads (white wheat, maize, wheat/maize, and maize/rye breads). Samples were processed with microwave assisted digestion and mineral composition was determined with a high-resolution continuum-source atomic absorption spectrometer with flame and graphite furnace. Bread contributes to an equilibrated diet since it is rich in several minerals (0.21 mg/100 g of copper in wheat bread to 537 mg/100 g of sodium in maize/rye bread). Maize/rye bread presented the highest content of all minerals (except phosphorous and chloride), while the lowest levels were mainly found in wheat bread. Median sodium concentrations (422-537 mg/100 g) represented more than 28% of the recommended daily allowance, being in close range of the maximum Portuguese limit (550 mg/100 g). Maize/rye bread exhibited the highest DMI of manganese (181%), sodium (36%), magnesium (32%), copper (32%), zinc (24%), iron (22%), potassium (20%), and calcium (3.0%). A Principal Component Analysis (PCA) model based on the mineral content allowed the differentiation among white wheat, maize, and maize/rye bread. Zinc, magnesium, manganese, iron, phosphorus, potassium, copper, and calcium proved to be good chemical markers to differentiate bread compositions.

Nutrients Composition in Fit Snacks Made from Ostrich, Beef and Chicken Dried Meat.

The aim of the study was to compare three types of meat snacks made from ostrich, beef, and chicken meat in relation to their nutrients content including fat, fatty acids, heme iron, and peptides, like anserine and carnosine, from which human health may potentially benefit. Dry meat samples were produced, from one type of muscle, obtained from ostrich (m.ambiens), beef (m. semimembranosus), and broiler chicken meat (m. pectoralis major). The composition of dried ostrich, beef, and chicken meat, with and without spices was compared. We show that meat snacks made from ostrich, beef, and chicken meat were characterized by high concentration of nutrients including proteins, minerals (heme iron especially in ostrich, than in beef), biologically active peptides (carnosine-in beef, anserine-in ostrich then in chicken meat). The, beneficial to human health, n-3 fatty acids levels differed significantly between species. Moreover, ostrich jerky contained four times less fat as compared to beef and half of that in chicken. In conclusion we can say that dried ostrich, beef, and chicken meat could be a good source of nutritional components.

Potential of Laurencia obtusa as a substrate for the development of a probiotic Saccharomyces cerevisiae.

Laurencia obtusa (Ceramiales, Rhodophyta) has tremendous nutritional value, being high in proteins, oligosaccharides, vitamins, essential minerals, and fatty acids, and it is a rich source of amino acids and trace elements. In this study, L. obtusa was extracted and subjected to phenolic, sugar and flavonoid analyses.The fatty acid, vitamin and phytosterol contents in Saccharomyces cerevisiae were evaluated when it was incubated with L. obtusa dry biomass. The fatty acids in the lipid extract were analysed after converting them into methyl esters using gas chromatography, and vitamin concentrations were measured using high-performance liquid chromatography (HPLC). According to the achieved results, the total fatty acid levels and vitamin contents of the S. cerevisiae prepared with algal extract increased at different rates. Our results showed that α-tocopherol decreased in the group in which the S. cerevisiae was added the algal extract. When compared to the control group, ergesterol increased in the group in which L. obtusa extract was added. Additionally, when compared to the control group in which L. obtusa extract was added, stearic acid (18:0), oleic acid (18:1) and linoleic acid (18:2) increased in the other groups. Palmitoleic acid (16:1) increased in the L. obtusa culture medium, but palmitic acid decreased in the L. obtusa culture medium. In conclusion, it was determined that the L. obtusa extract added to the development medium of S. cerevisiae caused differences in the synthesis of some vitamins and fatty acids.

Biosynthesis of copper carbonate nanoparticles by ureolytic fungi.

In this research, the ureolytic fungi Neurospora crassa, Pestalotiopsis sp. and Myrothecium gramineum were investigated for the preparation of nanoscale copper carbonate and the role of fungal extracellular protein in such mineral formation. After incubation in urea-modified media, carbonate-laden fungal supernatants were used for the precipitation of copper carbonate, with experimental results agreeing closely with those obtained using geochemical modelling (Geochemist's Workbench). Compared with commercial and chemically synthesized copper carbonate, the minerals obtained using fungal supernatants were nanoscale and showed varying morphologies. It was found that extracellular protein played an important role in determining the size and morphology of the carbonate minerals precipitated, and after mixture with CuCl2 and resultant copper carbonate precipitation, more than 80% protein was removed from the N. crassa supernatant. Moreover, with addition of extracellular protein extracted from different fungal supernatants or standard bovine serum albumin, more than 96% of protein was removed by carbonate mineral precipitation. These results provide direct experimental evidence for the preparation of copper carbonate nanoparticles utilizing fungal ureolytic activity and show that fungal extracellular protein plays an important role in the formation and size of specific nano metal carbonates. Such a process provides opportunities for production of specific and/or novel metal carbonate nanoparticles of applied relevance, and as precursors of other useful biomineral products such as oxides.

Preparation and biocompatibility of demineralized bone matrix/sodium alginate putty.

Demineralized bone matrix (DBM) powder is widely used for bone regeneration due to its osteoinductivity and osteoconductivity. However, difficulties with handling, tendency to migrate from graft sites and lack of stability after surgery sometimes limit the clinical utility of this material. In this work, the possibility of using sodium alginate (ALG) carrier to deliver DBM powder was assessed. DBM-ALG putty with the DBM:ALG weight ratio of 5:5, 6:4, 7:3, 8:2 were prepared, respectively. The properties of the formed composite, including discrete degree, washout property, pH, equilibrium swelling as well as cytotoxicity in vivo, were adopted to ascertain the optimal ratio of DBM and ALG. The discrete diameter increased from 1.25 cm (5:5) to 2.08 cm (8:2) with the increase of DBM content. There was significant difference between the 8:2 group and the other groups in discrete diameter. The ratio of DBM had a significant effect on the swelling value. The pH of composites showed an increase trend with the DBM ratio's increase, when the ratio reached 7:3, the pH (7.22) was approximately equal to the body fluid. The proliferation of MC3T3-E1 cells was inhibited in the 5:5, 6:4 and 7:3 groups, while a slightly increased in the 8:2 group. The DBM-ALG with the optimal ratio of 7:3 was confirmed based on the results of the above mentioned. The histocompatibility of DBM-ALG (7:3) was examined using a rat model in which the materials were implanted subcutaneously, compared with the polyethylene, ALG and DBM. The study in vivo showed DBM-ALG (7:3) had a lower inflammatory response than DBM, a higher vascularization than ALG. The osteoinduction of DBM-ALG (7:3) was evaluated by co-culturing with MC3T3-E1 in vitro, compared with the DMEM, ALG and DBM. The results indicated calcification area in the DBM-ALG group was similar to that in the DBM group, larger than ALG group and DMEM group. The DBM-ALG (7:3) putty is promising as a directly injectable graft for repair of bone defect.

Isolation of a wide range of minerals from a thermally treated plant: Equisetum arvense, a Mare's tale.

Silica is the second most abundant biomineral being exceeded in nature only by biogenic CaCO3. Many land plants (such as rice, cereals, cucumber, etc.) deposit silica in significant amounts to reinforce their tissues and as a systematic response to pathogen attack. One of the most ancient species of living vascular plants, Equisetum arvense is also able to take up and accumulate silica in all parts of the plant. Numerous methods have been developed for elimination of the organic material and/or metal ions present in plant material to isolate biogenic silica. However, depending on the chemical and/or physical treatment applied to branch or stem from Equisetum arvense; other mineral forms such glass-type materials (i.e. CaSiO3), salts (i.e. KCl) or luminescent materials can also be isolated from the plant material. In the current contribution, we show the chemical and/or thermal routes that lead to the formation of a number of different mineral types in addition to biogenic silica.

Application of the electro-Fenton process for cutting fluid mineralization.

Organic compound is the main pollutant in industrial effluent. Conventional wastewater treatment processes are inefficient for the removal of toxic or non-biodegradable organic pollutants. Advanced electrochemical depollution is a very efficient and economic method, suitable when the wastewater contains toxic and recalcitrant organic pollutants. The aim of the present study was to investigate the application of the electro-Fenton (EF) process for the degradation and mineralization of a stable oil-in-water emulsion (0.01% in v/v). The effects of operating parameters such as cathode material (graphite, Ti/Pt and steel), nature (Na2SO4, NaNO3 and NaCl) and dose of electrolyte (25-75 mM), initial ferrous ions concentration (1-75 mM), current intensity (0.1-0.2 A) and operating time, on chemical oxygen demand (COD) removal efficiency, were studied. Results showed that the EF method can be used efficiently for the degradation of stable cutting oil emulsion. For considered initial conditions (bubbling compressed air at 1 L/min, 0.15 A, pH 3, [Na2SO4]=0.05 M, [FeSO4]=0.015 M, COD0=400 mg O2/L), the best removal efficiencies were obtained under the following conditions: graphite as cathode material, 180 min for treatment duration and 0.05 M [Na2SO4]. For these conditions, treatment of 250 mL of emulsion led to 93.6% of cutting fluid mineralization, which correspond to 25 mg O2/L of final COD, 19 kWh/m3 of treated wastewater and 24.039 kWh/kg of COD removal.

Ultrastructure and mineral composition of the cornea cuticle in the compound eyes of a supralittoral and a marine isopod.

The cuticle of the cornea in Crustacea is an interesting example of a composite material compromising between two distinct functions. As part of the dioptric apparatus of the ommatidia within the complex eye it forms transparent micro-lenses that should as well maintain the mechanical stability of the head capsule. We analyzed the ultrastructure and composition of the isopod cornea cuticle of the terrestrial species Ligia oceanica and the marine Sphaeroma serratum. We used a variety of tissue preparation methods, electron microscopic techniques as well as electron microprobe analysis and Raman spectroscopic imaging. The results reveal various structural adaptations that likely increase light transmission. These are an increase in the thickness of the epicuticle, a reduction of the thickness of the outer layer of calcite, a spatial restriction of pore canals to interommatidial regions, and, for S. serratum only, an increase in calcite crystal size. In both species protein-chitin fibrils within the proximal exocuticle form a peculiar reticular structure that does not occur within the cuticle of the head capsule. In L. oceanica differential mineralization results in a spherically shaped interface between mineralized and unmineralized endocuticle, likely an adaptation to increase the refractive power of the cornea maintaining the mechanical stability of the cuticle between the ommatidia. The results show that the habitat and differences in the general structure of the animal's cuticle affect the way in which the cornea is adapted to its optical function.

Small-angle neutron scattering studies of mineralization on BSA coated citrate capped gold nanoparticles used as a model surface for membrane scaling in RO wastewater desalination.

Bovine serum albumin (BSA) coated on citrate capped gold nanoparticles (BSA-GNPs) was exposed to a simulated wastewater effluent (SSE) in order to study the mineralization and thereby mimic scaling at biofouled membranes of reverse osmosis (RO) wastewater desalination plants. RO is a leading technology of achieving freshwater quality as it has the capability of removing both dissolved inorganic salts and organic contaminants from tertiary wastewater effluents. The aim was to better understand one of the major problems facing this technology which is fouling of the membranes, mainly biofouling and scaling by calcium phosphate. The experiments were performed using the small-angle neutron scattering (SANS) technique. The nanoparticles, GNPs, stabilized by the citrate groups showed 30 Å large particles having a homogeneous distribution of gold and citrate with a gold volume fraction of the order of 1%. On the average two BSA monomers are grafted at 2.4 GNPs. The exposed BSA-GNPs to SSE solution led to immediate mineralization of stable composite particles of the order of 0.2 µm diameter and a mineral volume fraction between 50% and 80%. The volume fraction of the mineral was of the order of 10(-5), which is roughly 3 times larger but an order of magnitude smaller than the maximum possible contents of respectively calcium phosphate and calcium carbonate in the SSE solution. Considering the extreme low solubility product of calcium phosphate, we suggest total calcium phosphate and partially (5-10%) calcium carbonate formation in the presence of BSA-GNPs.