Nutritional Potential and Toxicological Evaluation of Tetraselmis sp. CTP4 Microalgal Biomass Produced in Industrial Photobioreactors

Commercial production of microalgal biomass for food and feed is a recent worldwide trend. Although it is common to publish nutritional data for microalgae grown at the lab-scale, data about industrial strains cultivated in an industrial setting are scarce in the literature. Thus, here we present the nutritional composition and a microbiological and toxicological evaluation of Tetraselmis sp. CTP4 biomass, cultivated in 100-m3 photobioreactors at an industrial production facility (AlgaFarm). This microalga contained high amounts of protein (31.2 g/100 g), dietary fibres (24.6 g/100 g), digestible carbohydrates (18.1 g/100 g) and ashes (15.2 g/100 g), but low lipid content (7.04 g/100 g). The biomass displayed a balanced amount of essential amino acids, n-3 polyunsaturated fatty acids, and starch-like polysaccharides. Significant levels of chlorophyll (3.5 g/100 g), carotenoids (0.61 g/100 g), and vitamins (e.g., 79.2 mg ascorbic acid /100 g) were also found in the biomass. Conversely, pathogenic bacteria, heavy metals, cyanotoxins, mycotoxins, polycyclic aromatic hydrocarbons, and pesticides were absent. The biomass showed moderate antioxidant activity in several in vitro assays. Taken together, as the biomass produced has a balanced biochemical composition of macronutrients and (pro-)vitamins, lacking any toxic contaminants, these results suggest that this strain can be used for nutritional applications.

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Production and Physicochemical Characterization of Gelatin and Collagen Hydrolysates from Turbot Skin Waste Generated by Aquaculture Activities

Marine Drugs ◽

10.3390/md19090491 ◽

2021 ◽

Vol 19 (9) ◽

pp. 491

Author(s):

Jesus Valcarcel ◽

Javier Fraguas ◽

Carolina Hermida-Merino ◽

Daniel Hermida-Merino ◽

Manuel M. Piñeiro ◽

...

Keyword(s):

Amino Acids ◽

Structural Integrity ◽

Physicochemical Characterization ◽

Essential Amino Acids ◽

Storage And Loss Moduli ◽

Food And Feed ◽

Collagen Hydrolysates ◽

First Time ◽

By Products

Rising trends in fish filleting are increasing the amount of processing by-products, such as skins of turbot, a flatfish of high commercial value. In line with circular economy principles, we propose the valorization of turbot skins through a two-step process: initial gelatin extraction described for the first time in turbot, followed by hydrolysis of the remaining solids to produce collagen hydrolysates. We assayed several methods for gelatin extraction, finding differences in gelatin properties depending on chemical treatment and temperature. Of all methods, the application of NaOH, sulfuric, and citric acids at 22 °C results in the highest gel strength (177 g), storage and loss moduli, and gel stability. We found no relation between mechanical properties and content of pyrrolidine amino acids, but the best performing gelatin displays higher structural integrity, with less than 30% of the material below 100 kDa. Collagen hydrolysis was more efficient with papain than alcalase, leading to a greater reduction in Mw of the hydrolysates, which contain a higher proportion of essential amino acids than gelatin and show high in vitro anti-hypertensive activity. These results highlight the suitability of turbot skin by-products as a source of gelatin and the potential of collagen hydrolysates as a functional food and feed ingredient.

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Characterization of Antibacterial Proanthocyanidins of Dalbergia monetaria, an Amazonian Medicinal Plant, by UHPLC-HRMS/MS

Planta Medica ◽

10.1055/a-1170-8016 ◽

2020 ◽

Vol 86 (12) ◽

pp. 858-866

Author(s):

Patricia Homobono Brito de Moura ◽

Amaryllis Almeida de Sousa ◽

Andrea Porzel ◽

Ludger A. Wessjohann ◽

Ivana Correa Ramos Leal ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pathogenic Bacteria ◽

Neutral Loss ◽

Antibacterial Activities ◽

Quinone Methide ◽

In Vitro Assays ◽

Fragmentation Pattern ◽

Bacterial Strains ◽

Tract Infections

Abstract Dalbergia monetaria is an Amazonian plant whose bark is widely used to treat urinary tract infections. This paper describes a bio-guided study of ethanolic extracts from the bark and leaves of D. monetaria, in a search for metabolites active against human pathogenic bacteria. In vitro assays were performed against 10 bacterial strains, highlighting methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Fractioning of the extracts was performed using instrumental and classical techniques, and samples were characterized by UHPLC-HRMS/MS. Ethyl acetate fractions from bark and leaves showed similar antibacterial activities. EAFB is enriched in isoflavone C-glucosides and EAFL enriched in proanthocyanidins. Subfractions from EAFL presented higher activity and showed a complex profile of proanthocyanidins constructed by (epi)-cassiaflavan and (epi)-catechin units, including dimers, trimers and tetramers. The fragmentation pattern emphasized the neutral loss of cassiaflavan units by quinone-methide fission. Fraction SL7-6, constituted by (ent)-cassiaflavan-(ent)-cassiaflavan-(epi)-catechin isomers, showed the lowest MIC against the S. aureus and P. aeruginosa with values corresponding to 64 and 32 µg/mL, respectively. Cassiaflavan-proanthocyanidins have not been found previously in another botanical genus, except in Cassia, and the traditional medicinal use of D. monetaria might be related to the antibacterial activity of proanthocyanidins characterized in the species.

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Beauvericin and Enniatins: In Vitro Intestinal Effects

Toxins ◽

10.3390/toxins12110686 ◽

2020 ◽

Vol 12 (11) ◽

pp. 686 ◽

Cited By ~ 2

Author(s):

Alessia Bertero ◽

Paola Fossati ◽

Doriana Eurosia Angela Tedesco ◽

Francesca Caloni

Keyword(s):

Gastrointestinal Tract ◽

Health Problem ◽

Toxicological Evaluation ◽

Intestinal Toxicity ◽

Regulatory Aspects ◽

Food And Feed ◽

Major Route ◽

Route Of Exposure ◽

Species Specific

Food and feed contamination by emerging mycotoxins beauvericin and enniatins is a worldwide health problem and a matter of great concern nowadays, and data on their toxicological behavior are still scarce. As ingestion is the major route of exposure to mycotoxins in food and feed, the gastrointestinal tract represents the first barrier encountered by these natural contaminants and the first structure that could be affected by their potential detrimental effects. In order to perform a complete and reliable toxicological evaluation, this fundamental site cannot be disregarded. Several in vitro intestinal models able to recreate the different traits of the intestinal environment have been applied to investigate the various aspects related to the intestinal toxicity of emerging mycotoxins. This review aims to depict an overall and comprehensive representation of the in vitro intestinal effects of beauvericin and enniatins in humans from a species-specific perspective. Moreover, information on the occurrence in food and feed and notions on the regulatory aspects will be provided.

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Concentrated Bioshell Calcium Oxide (BiSCaO) Water Kills Pathogenic Microbes: Characterization and Activity

Molecules ◽

10.3390/molecules25133001 ◽

2020 ◽

Vol 25 (13) ◽

pp. 3001 ◽

Cited By ~ 1

Author(s):

Shingo Nakamura ◽

Masayuki Ishihara ◽

Yoko Sato ◽

Tomohiro Takayama ◽

Sumiyo Hiruma ◽

...

Keyword(s):

Calcium Oxide ◽

Influenza A ◽

Pathogenic Bacteria ◽

Colloidal Dispersion ◽

In Vitro Assays ◽

Clean Water ◽

Influenza A H1n1 ◽

Pathogenic Microbes ◽

O 157

Bioshell calcium oxide (BiSCaO) exhibits deodorizing properties and broad microbicidal activity. In this study, we examined possible utility of BiSCaO Water for that purpose. BiSCaO Water was prepared by adding 10 wt% BiSCaO to clean water and gently collecting the supernatant in a bottle. The same volume of clean water was gently poured onto the BiSCaO precipitate and the supernatant was gently collected in a bottle; this process was repeated fifty times. The produced BiSCaO Water contained nanoparticles (about 400–800 nm) composed of smaller nanoparticles (100–200 nm), and was colorless and transparent, with a pH > 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli such as NBRC 3972 and O-157:H7, Pseudomonas aeruginosa, Salmonella, and Staphylococcus aureus within 15 min. We compared BiSCaO Water with the other microbicidal reagents such as ethanol, BiSCaO, BiSCa(OH)2 suspensions, povidone iodine, NaClO, BiSCaO dispersion and colloidal dispersion with respect to deodorization activity and microbicidal efficacy. The results showed that BiSCaO Water was a potent reagent with excellent deodorization and disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).

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Processing Optimization and Toxicological Evaluation of “Lead-Free” Piezoceramics: A KNN-Based Case Study

Materials ◽

10.3390/ma14154337 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4337

Author(s):

Antonio Iacomini ◽

Juan Antonio Tamayo-Ramos ◽

Carlos Rumbo ◽

Irem Urgen ◽

Marzia Mureddu ◽

...

Keyword(s):

Average Crystallite Size ◽

Lead Free ◽

In Vitro Assays ◽

X Ray Diffraction ◽

Toxicological Evaluation ◽

Free System ◽

Cellular Models ◽

Industrial Community ◽

Processing Optimization

Due to the ever-increasing limitations of the use of lead-based materials, the manufacturing of lead-free piezoceramics with competitive piezoelectric properties and established nontoxicity is considered a priority for the scientific and industrial community. In this work, a lead-free system based on sodium potassium niobate (KNN), opportunely modified with MgNb2O6 (MN), was prepared through a combination of a mechanochemical activation method and air sintering, and its toxicity was evaluated. The effect of the mechanical processing on the microstructure refinement of the processed powders was established by X-ray diffraction and the average crystallite size content of the Nb2O5 species was evaluated. The experimental evidence was rationalized using a phenomenological model which permitted us to obtain the amount of powder processed at each collision and to optimize the activation step of the pre-calcined reagents. This influenced the final density and piezoresponse of the as-sintered pellets, which showed optimal properties compared with other KNN systems. Their toxicological potential was evaluated through exposure experiments to the pulverized KNN-based pellets, employing two widely used human and environmental cellular models. The in vitro assays proved, under the selected conditions, the absence of cytotoxicity of KNN-bases systems here studied.

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Enzyme-Assisted Release of Antioxidant Peptides from Porphyra dioica Conchocelis

Antioxidants ◽

10.3390/antiox10020249 ◽

2021 ◽

Vol 10 (2) ◽

pp. 249

Author(s):

Filipa B. Pimentel ◽

Marlene Machado ◽

Maria Cermeño ◽

Thanyaporn Kleekayai ◽

Susana Machado ◽

...

Keyword(s):

Antioxidant Activity ◽

Amino Acid ◽

Dry Weight ◽

Essential Amino Acids ◽

Life Cycle Stage ◽

In Vitro Assays ◽

Total Amino Acid ◽

Amino Acid Profiles ◽

Amino Acid Contents

The conchocelis life cycle stage of P. dioica represents an unexplored source of bioactive compounds. The aim of this study was to generate and characterise, for the first time, hydrolysates of conchocelis using a specific combination of proteases (Prolyve® and Flavourzyme®). Hydrolysate molecular mass distribution and free amino acid contents were assessed, and the antioxidant activity was determined using a range of in vitro assays. The protein content and the total amino acid profiles of conchocelis were also studied. Conchocelis contained ~25% of protein (dry weight basis) and had a complete profile of essential amino acids. Direct sequential enzymatic treatment modified the profile of the generated compounds, increasing the amount of low molecular weight peptides (<1 kDa). There was a significant improvement in the antioxidant activity of the hydrolysates compared with the control (up to 2.5-fold), indicating their potential as a novel source of antioxidant ingredients.

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Red Algae as Source of Nutrients with Antioxidant and Antimicrobial Potential

Proceedings ◽

10.3390/foods_2020-07646 ◽

2020 ◽

Vol 70 (1) ◽

pp. 5

Author(s):

María. Carpena ◽

Cristina Caleja ◽

Paula García-Oliveira ◽

Carla Pereira ◽

Marina Sokovic ◽

...

Keyword(s):

Antimicrobial Activity ◽

Organic Acids ◽

Red Algae ◽

Antimicrobial Agents ◽

Biological Properties ◽

Nutritional Composition ◽

In Vitro Assays ◽

Antimicrobial Potential ◽

Antioxidant And Antimicrobial Activity

Seaweeds have been consumed since ancient times in different cultures, especially in Asian regions. Currently, several scientific studies have highlighted the nutritional value of algae as well as their biological properties. The present work was directed towards the determination of the nutritional composition (ash, protein, fat, carbohydrate content and energy value), the organic acids content, and also the antioxidant and antimicrobial activity of three typical red algae from Galicia: Chondrus crispus, Mastocarpus stellatus and Gigartina pistillata. The nutritional profile was determined by the methods described by AOAC, while organic acids were determined by UPFLC-PDA. The antioxidant activity was assessed using two in vitro assays: TBARS and OxHLIA. At last, antimicrobial activity was tested against two Gram (−), three Gram (+) and three fungus species. The results showed a similar nutritional composition among the three algae, with a low-fat content and a high content of proteins, carbohydrates and energy. Finally, in vitro assays showed significant antioxidant capacity of the three algae and antimicrobial potential against all the tested microorganisms. Thus, the study shows the potential of red algae to be part of the human diet, due to their nutritional content and bioactive properties, acting as antioxidant and antimicrobial agents.

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Antibacterial in vitro assays of new -aminoethers and derivatives against Gram-negative and Gram-positive pathogenic bacteria

African Journal of Microbiology Research ◽

10.5897/ajmr2015.7591 ◽

2015 ◽

Vol 9 (40) ◽

pp. 2111-2118

Author(s):

Duque Natalia ◽

Carabali Mary ◽

Ben iacute tez Neyla ◽

Castillo Juan ◽

Abonia Rodrigo

Keyword(s):

Pathogenic Bacteria ◽

In Vitro Assays ◽

Gram Positive ◽

Gram Negative

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Animal Models of Type III Secretion System-Mediated Pathogenesis

Pathogens ◽

10.3390/pathogens8040257 ◽

2019 ◽

Vol 8 (4) ◽

pp. 257 ◽

Cited By ~ 1

Author(s):

Julia A. Hotinger ◽

Aaron E. May

Keyword(s):

Animal Models ◽

Type Iii Secretion ◽

Pathogenic Bacteria ◽

Type Iii Secretion System ◽

Secretion System ◽

New Drugs ◽

In Vitro Assays ◽

Salmonella Spp ◽

Type Iii

The type III secretion system (T3SS) is a conserved virulence factor used by many Gram-negative pathogenic bacteria and has become an important target for anti-virulence drugs. Most T3SS inhibitors to date have been discovered using in vitro screening assays. Pharmacokinetics and other important characteristics of pharmaceuticals cannot be determined with in vitro assays alone. In vivo assays are required to study pathogens in their natural environment and are an important step in the development of new drugs and vaccines. Animal models are also required to understand whether T3SS inhibition will enable the host to clear the infection. This review covers selected animal models (mouse, rat, guinea pig, rabbit, cat, dog, pig, cattle, primates, chicken, zebrafish, nematode, wax moth, flea, fly, and amoeba), where T3SS activity and infectivity have been studied in relation to specific pathogens (Escherichia coli, Salmonella spp., Pseudomonas spp., Shigella spp., Bordetella spp., Vibrio spp., Chlamydia spp., and Yersinia spp.). These assays may be appropriate for those researching T3SS inhibition.

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Effect of Traditional Processing Methods on the Nutritional Composition of Sorghum (Sorghum bicolour L. Moench) Flour

European Journal of Nutrition & Food Safety ◽

10.9734/ejnfs/2020/v12i730252 ◽

2020 ◽

pp. 69-77

Author(s):

T. Tamilselvan ◽

Archana Kushwaha

Keyword(s):

Protein Content ◽

Protein Digestibility ◽

Essential Amino Acids ◽

Nutritional Composition ◽

Total Phenol Content ◽

Lysine Content ◽

Processing Methods ◽

Sorghum Flour ◽

Traditional Processing

Sorghum is a drought-resistant crop grown widely in various parts of India. It has low protein content, highly deficient in essential amino acids lysine and tryptophan and high anti-nutritional content. Therefore, keeping in view the present study aimed to determine the effect of traditional processing methods such as fermentation, malting and roasting on the proximate composition, anti-nutritional factors, protein digestibility and lysine content of sorghum. The results showed that ash content increased from 1.73 to 1.89% during roasting. Fermentation increased crude protein content from 8.27 to 8.98% and in vitro protein digestibility from 13.62 to 69.63%. Malting decreased the crude fat content from 1.87 to 1.22% while it shows a significant increase in crude fiber content from 3.34 to 4.26% and carbohydrate content from 84.77 to 86.15%. Total phenol content reduced from 92.62 to 48.40 mg GAE/100 g, and tannin content reduced from 8.46 to 1.25 mg TAE/100 g during fermentation. The lysine content increased significantly during fermentation (1.88 g/16 g of N) and malting (1.94 g/16 g of N). Natural fermentation of sorghum flour found to have improved nutritional quality than other processing methods.

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