84 research outputs found
Chlamydomonas reinhardtii: A Factory of Nutraceutical and Food Supplements for Human Health
No full textChlamydomonas reinhardtii (C. reinhardtii) is one of the most well-studied microalgae organisms that revealed important information for the photosynthetic and metabolic processes of plants and eukaryotes. Numerous extensive studies have also underpinned its great potential as a biochemical factory, capable of producing various highly desired molecules with a direct impact on human health and longevity. Polysaccharides, lipids, functional proteins, pigments, hormones, vaccines, and antibodies are among the valuable biomolecules that are produced spontaneously or under well-defined conditions by C. reinhardtii and can be directly linked to human nutrition and diet. The aim of this review is to highlight the recent advances in the field focusing on the most relevant applications related to the production of important biomolecules for human health that are also linked with human nutrition and diet. The limitations and challenges are critically discussed along with the potential future applications of C. reinhardtii biomass and processed products in the field of nutraceuticals and food supplements. The increasing need for high-value and low-cost biomolecules produced in an environmentally and economy sustainable manner also underline the important role of C. reinhardtii
Trends in biosensors for the detection of Staphylococcus aureus as a key cause of foodborne illnesses worldwide
No full textLessons from LaGrand: An Argument for the Domestic Enforceability of Treaty-Based Rights Under International Prisoner Transfer Treaties
No full textLouis Antonacci, an attorney for the U.S Army Corps of Engineers, argues that foreign nationals incarcerated in United States state prisons, who are nationals of countries that are parties to the Convention on the Transfer of Sentenced Persons, have a right to be notified of their right to request a transfer. Furthermore, these international prison transfer regimes, of which the Convention on the Transfer of Sentenced Persons is but one, and which the United States is a signatory, should apply with equal force in state prison and proceedings as it does in federal prisons and proceedings. The disparate treatment of foreign nationals determined by state or federal incarceration creates a divided front in foreign policy. The views expressed in this article are those of the author and do not reflect those of the U.S. Army Corps of Engineers
Fighting nosocomial antibiotic-resistant infections through rapid and sensitive isothermal amplification-powered point-of-care (POC) diagnostics
No full textPoint-of-care nucleic acid screening is a crucial clinical practice for addressing nosocomial infections in developed and developing countries, as well as in settings where a centralized laboratory approach encounters limitations. This rapid and accurate detection is important not only for the timely initiation of appropriate antibiotic therapy but also for resolving outbreaks and minimizing subsequent antimicrobial resistance. Current systems to diagnose nosocomial infectious diseases are mainly culture-based or PCR-based methods, with limitations of complex and time/cost-consuming procedures. Designing an integrated device that can simultaneously deliver sample preparation, nucleic acid amplification, and detection in a sensitive, specific, and timely manner remains a challenge. This review reports recent advances that may address this challenge, with particular emphasis on emerging developments that may lead to significant improvements in the point-of-care diagnosis of multidrug-resistant pathogens and new directions that can be used to guide antibiotic therap
NYMPHA per i materiali lapidei - NYMPHA for marbles (Progetto NYMPHA per la protezione dei materiali lapidei nei Beni Culturali)
No full textVivere nell’era del cambiamento climatico ha portato la ricerca a porre maggiore attenzione alla salvaguardia dell’ambiente, intraprendendo attraverso lo sviluppo tecnologico azioni consapevoli e sostenibili volte a migliorare le prospettive ambientali future. Il progetto NYMPHA si inserisce in questo contesto, cercando di rispondere alla necessità di fornire un prodotto per il restauro e la conservazione dei Beni Culturali che sia non dannoso per uomo e ambiente, totalmente caratterizzato dal punto di vista chimico e compatibile con le superfici antiche polimateriche. Il prodotto1, un estratto di polisaccaridi di microalghe, è innovativo per la sua origine e ha potenzialità antimicotiche, antibatteriche e di miglioramento strutturale. Ad oggi i polisaccaridi, ottenuti seguendo quattro protocolli di estrazione, sono stati applicati su provini inorganici (marmo bianco); successivamente è stata effettuata una caratterizzazione delle superfici lapidee per valutare l’efficacia del trattamento.
Ringraziamenti: questo lavoro è stato supportato dal POR-FESR Progetti Gruppi di Ricerca Lazio Innova NYMPHA Project A0375-2020-36489.
1- Masi, A., Medeghini, L., Masi, A., Sadori, L., Leonelli, F., Favero, G., & Antonacci, A. (2021). Natural polysaccharides from microalgae for the protection of cultural heritage. SMART ELAB, 16, 24. https://doi.org/10.30441/smartelab.v16i.12
The plastoquinol–plastoquinone exchange mechanism in photosystem II: insight from molecular dynamics simulations
No full textIn the photosystem II (PSII) of oxygenic photosynthetic organisms, the reaction center (RC) core mediates the light-induced electron transfer leading to water splitting and production of reduced plastoquinone molecules. The reduction of plastoquinone to plastoquinol lowers PSII affinity for the latter and leads to its release. However, little is known about the role of protein dynamics in this process. Here, molecular dynamics simulations of the complete PSII complex embedded in a lipid bilayer have been used to investigate the plastoquinol release mechanism. A distinct dynamic behavior of PSII in the presence of plastoquinol is observed which, coupled to changes in charge distribution and electrostatic interactions, causes disruption of the interactions seen in the PSII–plastoquinone complex and leads to the “squeezing out” of plastoquinol from the binding pocket. Displacement of plastoquinol closes the second water channel, recently described in a 2.9 Å resolution PSII structure (Guskov et al. in Nat Struct Mol Biol 16:334–342, 2009), allowing to rule out the proposed “alternating” mechanism of plastoquinol–plastoquinone exchange, while giving support to the “single-channel” one. The performed simulations indicated a pivotal role of D1-Ser264 in modulating the dynamics of the plastoquinone binding pocket and plastoquinol–plastoquinone exchange via its interaction with D1-His252 residue. The effects of the disruption of this hydrogen bond network on the PSII redox reactions were experimentally assessed in the D1 site-directed mutant Ser264Lys
A Proof-of-Concept Electrochemical Cytosensor Based on Chlamydomonas reinhardtii Functionalized Carbon Black Screen-Printed Electrodes: Detection of Escherichia coli in Wastewater as a Case Study
No full textHerein, we report a proof-of-concept algal cytosensor for the electrochemical quantification of bacteria in wastewater, exploiting the green photosynthetic alga Chlamydomonas reinhardtii immobilized on carbon black (CB) nanomodified screen-printed electrodes. The CB nanoparticles are used as nanomodifiers, as they are able to sense the oxygen produced by the algae and thus the current increases when algae are exposed to increasing concentrations of bacteria. The sensor was tested on both standard solutions and real wastewater samples for the detection Escherichia coli in a linear range of response from 100 to 2000 CFU/100 mL, showing a limit of detection of 92 CFU/100 mL, in agreement with the maximum E. coli concentration established by the Italian law for wastewater (less than 5000 CFU/100 mL). This bacterium was exploited as a case study target of the algal cytosensor to demonstrate its ability as an early warning analytical system to signal heavy loads of pathogens in waters leaving the wastewater treatment plants. Indeed, the cytosensor is not selective towards E. coli but it is capable of sensing all the bacteria that induce the algae oxygen evolution by exploiting the effect of their interaction. Other known toxicants, commonly present in wastewater, were also analyzed to test the cytosensor selectivity, with any significant effect, apart from atrazine, which is a specific target of the D1 protein of the Chlamydomonas photosystem II. However, the latter can also be detected by chlorophyll fluorescence simultaneously to the amperometric measurements. The matrix effect was evaluated, and the recovery values were calculated as 105 ± 8, 83 ± 7, and 88 ± 7% for 1000 CFU/100 mL of E. coli in Lignano, San Giorgio, and Pescara wastewater samples, respectively
The NYMPHA algae extract as a new consolidant for the restoration of cultural heritage: studies and considerations on its effectiveness on painted marble
No full textThis work aimed to assess the potential efficacy of a novel polysaccharides-based extract as a green consolidant for the pictorial layer on marble substrates. Understanding its properties could lead to determining whether it can ensure the correct conservation and transmission of the cultural heritage. Four different types of marble specimens were prepared with paint based on malachite (egg, tempera grassa, rabbit glue, and linseed oil as binders). Colorimetric analyses, peeling tests, SEM-EDS, and FTIR spectroscopy were used to test the properties of the consolidant. Results reveal that no aesthetic changes occur when using the extract on painted surfaces and that the cohesive properties of most pictorial films increase after its application, confirming the consolidating effect. In conclusion, the use of an innovative green product for the restoration of marble-painted surfaces can be considered a possible good solution for consolidating treatment. Through this initial explorative research, we suggest an innovative approach to the protection of cultural heritage that doesn’t cause harm to both the restorer’s health and the environment
Upcycling Microalgal Residues: Physicochemical Insights and Biocomposite Enhancement
No full textThe growing concern for environmental sustainability has led to an increased interest
in biodegradable materials derived from renewable resources. This study explores the
innovative use of residual biomass from the green photosynthetic microalga Chlamydomonas reinhardtii, left over after polysaccharide extraction, as a natural filler in the development of the compostable protein-based material SP-Milk®. The microalgal biomass was characterized using Fourier transform infrared spectroscopy (FTIR) and UV-Visible Spectroscopy to assess its chemical and structural composition. Subsequently, it was incorporated into a biodegradable protein matrix, and the resulting biocomposites were evaluated for mechanical and thermal properties. The results demonstrate that the incorporation of algal filler improves the mechanical strength and elasticity of the material while reducing its glass transition temperature, highlighting its potential for use in sustainable applications as a possible substitute for conventional plastics. The biocomposite materials developed, based on the protein-based material SP-Milk® and residual microalgal biomass, are environmentally friendly, contributing to the reduction in pollution and the risks associated with plastic accumulation. Thus, this study offers a simple, effective, and sustainable strategy for the valorization of microalgal biomass, enabling the production of biodegradable materials with enhanced mechanical performance, suitable for applications such as sustainable packaging within a circular economy framework
A dual electro-optical biosensor based on chlamydomonas reinhardtii immobilised on paper-based nanomodified screen-printed electrodes for herbicide monitoring
No full textThe indiscriminate use of herbicides in agriculture contributes to soil and water pollution, with important endanger- ing consequences on the ecosystems. Among the available analytical systems, algal biosensors have demonstrated to be valid tools thanks to their high sensitivity, cost-effectiveness, and eco-design. Herein, we report the development of a dual electro-optical biosensor for herbicide monitoring, based on Chlamydomonas reinhardtii whole cells immo- bilised on paper-based screen-printed electrodes modified with carbon black nanomaterials. To this aim, a systematic study was performed for the selection and characterisation of a collection among 28 different genetic variants of the alga with difference response behaviour towards diverse herbicide classes. Thus, CC125 strain was exploited as case study for the study of the analytical parameters. The biosensor was tested in standard solutions and real samples, providing high sensitivity (detection limit in the pico/nanomolar), high repeatability (RSD of 5% with n = 100), long lasting working (10 h) and storage stability (3 weeks), any interference in the presence of heavy metals and insecti- cides, and low matrix effect in drinking water and moderate effect in surface one
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