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
sp. CTP4 biomass, cultivated in 100-m
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,
-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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Amphotericin B (AmB) is still used as the gold standard for therapy against invasive fungal diseases. However, the use of AmB through oral administration is restricted due to its low ...solubility and stability in aqueous solution, which is the cause for its poor bioavailability and highly varying absorption. Therefore, an attempt has been made to enhance the solubility and stability of AmB to evaluate its bioactivity and safety for use as an inhaler by using a new excipient sodium deoxycholate sulfate (SDS) with aim of using it as a drug carrier for AmB. Therefore, SDS was formulated together with AmB as a dry powder by lyophilization. The dry powder was reconstituted in distilled water and evaluated its physicochemical properties such as zeta potential, particle size and pH to compare its solubility and stability of the formulations with a SDC–AmB (i.e., known as Fungizone®). In vitro toxicity studies were carried out with red blood cells (RBC) and respiratory cell lines. Bioactivity was determined by a micro-dilution method against Candida albicans and Cryptococcus neoformans. We found that SDS–AmB had a zeta potential (−45.53mV), which was higher than of Fungizone®; and produced a stable particle size in solution (73.8nm). The particle size distributions of both formulations were expressed as their mass median aerodynamic diameters (MMAD; 1.70 and 1.74μm), their fine particle fractions (FPF; 70 and 80%) and geometric standard deviations (GSD; 2.3 and 2.0), respectively. These values indicated that the sizes were appropriate for use in an inhaler. Pure AmB was found to hemolyse RBC and was very toxic to alveolar macrophage cells, as their viability rapidly declined from 93 to 56% when the AmB concentration increased from 1 to 8μg/mL. The SDS–AmB formulation had a significantly reduced toxicity compared to AmB. The results clearly indicated that the SDS–lipid based nanoparticles had the potential to be used as an alternative option to Fungizone® for an AmB formulation for inhalation.
Extracts of five halophytes from southern Portugal (Arthrocnemum macrostachyum, Mesembryanthemum edule, Juncus acutus, Plantago coronopus and Halimione portulacoides), were studied for antioxidant, ...anti-inflammatory and in vitro antitumor properties. The most active extracts towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were the methanol extracts of M. edule (IC₅₀ = 0.1 mg/mL) and J. acutus (IC₅₀ = 0.4 mg/mL), and the ether extracts of J. acutus (IC₅₀ = 0.2 mg/mL) and A. macrostachyum (IC₅₀ = 0.3 mg/mL). The highest radical scavenging activity (RSA) against the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical was obtained in the ether extract of J. acutus (IC₅₀ = 0.4 mg/mL) and H. portulacoides (IC₅₀ = 0.9 mg/mL). The maximum total phenolic content (TPC) was found in the methanol extract of M. edule (147 mg gallic acid equivalents (GAE)/g) and in the ether extract of J. acutus (94 mg GAE/g). Significant decreases in nitric oxide (NO) production were observed after incubation of macrophages with lipopolysaccharide (LPS) and the chloroform extract of H. portulacoides (IC₅₀ = 109 µg/mL) and the hexane extract of P. coronopus (IC₅₀ = 98.0 µg/mL). High in vitro cytotoxic activity and selectivity was obtained with the ether extract of J. acutus. Juncunol was identified as the active compound and for the first time was shown to display selective in vitro cytotoxicity towards various human cancer cells.
is a marine haptophyte rich in omega-3 polyunsaturated fatty acids (e.g., docosahexaenoic acid (DHA)) and carotenoids (e.g., fucoxanthin). Because of the nutraceutical applications of these ...compounds, this microalga is being used in aquaculture to feed oyster and shrimp larvae. In our earlier report,
organic crude extracts exhibited in vitro cytotoxic activity against human hepatocarcinoma (HepG2) cells. However, so far, the compound(s) accountable for the observed bioactivity have not been identified. Therefore, the aim of this study was to isolate and identify the chemical component(s) responsible for the bioactivity observed. Bioassay-guided fractionation through a combination of silica-gel column chromatography, followed by preparative thin layer chromatography (PTLC), led to the isolation of two diastereomers of a monoterpenoid lactone, namely, loliolide (
) and
-loliolide (
), isolated for the first time in this species. The structural elucidation of both compounds was carried out by GC-MS and 1D (
H and
C APT) and 2D (COSY, HMBC, HSQC-ed, and NOESY) NMR analysis. Both compounds significantly reduced the viability of HepG2 cells and were considerably less toxic towards a non-tumoral murine stromal (S17) cell line, although
-loliolide was found to be more active than loliolide.
A carbon catalyst obtained from glycerol, a byproduct of biodiesel processing, with a high density of sulfonic acid groups is prepared by carbonization and sulfurization (see figure). The carbon ...catalyst, with very good water tolerance and reusability, is useful for the preparation of biodiesel from fatty acids or from fatty acids present in vegetable oils and animal fats.
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Brown macroalgae have attracted attention because they display a wide range of biological activities, including antitumoral properties. Inthis study we isolated isololiolide from ...Cystoseira tamariscifolia for the first time.
To examine the therapeutical potential of isololiolide against tumor cell lines.
The structure of the compound was established and confirmed by 1D and 2D NMR as well as HRMS spectral analysis. The in vitro cytotoxicity was analyzed by colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in tumoral as well as in non-tumoral cell lines. Cell cycle arrest and induction of apoptosis were assessed by flow cytometry. Alteration of expression levels in proteins important in the apoptotic cascade was analyzed by western blotting.
Isololiolidewas isolated for the first time from the brown macroalga C.tamariscifolia. Isololiolide exhibited significant cytotoxic activity against three human tumoral cell lines, namely hepatocarcinoma HepG2 cells, whereas no cytotoxicity was found in non-malignant MRC-5 and HFF-1 human fibroblasts. Isololiolide completely disrupted the HepG2 normal cell cycle and induced significant apoptosis. Moreover, western blot analysis showed that isololiolide altered the expression of proteins that are important in the apoptotic cascade, increasing PARP cleavage and p53 expression while decreasing procaspase-3 and Bcl-2 levels.
Isololiolide isolated from C. tamariscifolia is able to exert a selective cytotoxic activity on hepatocarcinoma HepG2 cells as well as induce apoptosis through the modulation of apoptosis-related proteins.
The industrial microalga Tetraselmis sp. CTP4 is a promising candidate for aquaculture feed, novel food, cosmeceutical and nutraceutical due to its balanced biochemical profile. To further upgrade ...its biomass value, carotenogenesis was investigated by testing four environmental factors, namely temperature, light intensity, salinity and nutrient availability over different growth stages. The most important factor for carotenoid induction in this species is a sufficient supply of nitrates leading to an exponential growth of the cells. Furthermore, high temperatures of over 30 °C compared to lower temperatures (10 and 20 °C) induced the accumulation of carotenoids in this species. Remarkably, the two different branches of carotenoid synthesis were regulated depending on different light intensities. Contents of β-carotene were 3-fold higher under low light intensities (33 μmol m−2 s−1) while lutein contents increased 1.5-fold under higher light intensities (170 and 280 μmol m−2 s−1). Nevertheless, highest contents of carotenoids (8.48 ± 0.47 mg g−1 DW) were found upon a thermal upshift from 20 °C to 35 °C after only two days at a light intensity of 170 μmol m−2 s−1. Under these conditions, high contents of both lutein and β-carotene were reached accounting for 3.17 ± 0.18 and 3.21 ± 0.18 mg g−1 DW, respectively. This study indicates that Tetraselmis sp. CTP4 could be a sustainable source of lutein and β-carotene at locations where a robust, euryhaline, thermotolerant microalgal strain is required.
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•High temperature enhances carotenoid accumulation in Tetraselmis sp. CTP4.•Nitrogen repletion conditions are crucial for carotenoid induction.•Lutein accumulation is increased under conditions promoting growth.•β-carotene accumulation is increased under low irradiance.•Short-term stress (2 days) increases both lutein and β-carotene.
Microalgae are an untapped source of bioactive compounds with various biotechnological applications. Several species are industrially produced and commercialized for the feed or cosmetic industries, ...however, other applications in the functional food and pharmaceutical markets can be foreseen. In this study, nine industrial/commercial species were evaluated for in vitro antioxidant, calcium-chelating, anti-tumoral, and anti-inflammatory activities. The most promising extracts were fractionated yielding several promising fractions namely, of Tetraselmis striata CTP4 with anti-inflammatory activity (99.0 ± 0.8% reduction in TNF-α production in LPS stimulated human macrophages at 50 µg/mL), of Phaeodactylum Tricornutum with cytotoxicity towards cancerous cell lines (IC50 = 22.3 ± 1.8 μg/mL and 27.5 ± 1.6 μg/mL for THP-1 and HepG2, respectively) and of Porphyridium sp. and Skeletonema sp. with good chelating activity for iron, copper and calcium (IC50 = 0.047, 0.272, 0.0663 mg/mL and IC50 = 0.055, 0.240, 0.0850 mg/mL, respectively). These fractions were chemically characterized by GC–MS after derivatization and in all, fatty acids at various degrees of unsaturation were the most abundant compounds. Some of the species under study proved to be potentially valuable sources of antioxidant, metal chelators, anti-tumoral and anti-inflammatory compounds with possible application in the functional food and pharmaceutical industries.
In recent years, there has been increasing consumer interest in carotenoids, particularly of marine sustainable origin with applications in the food, cosmeceutical, nutritional supplement and ...pharmaceutical industries. For instance, microalgae belonging to the genus
Tetraselmis
are known for their biotechnologically relevant carotenoid profile. The recently isolated marine microalgal strain
Tetraselmis
sp. CTP4 is a fast-growing, robust industrial strain, which has successfully been produced in 100-m
3
photobioreactors. However, there are no reports on total carotenoid contents from this strain belonging to
T. striata/convolutae
clade. Although there are several reports on extraction methods targeting chlorophytes, extraction depends on the strength of cell coverings, solvent polarity and the nature of the targeted carotenoids. Therefore, this article evaluates different extraction methods targeting
Tetraselmis
sp. CTP4, a strain known to contain a mechanically resistant theca. Here, we propose a factorial experimental design to compare extraction of total carotenoids from wet and freeze-dried microalgal biomass using four different solvents (acetone, ethanol, methanol or tetrahydrofuran) in combination with two types of mechanical cell disruption (glass beads or dispersion). The extraction efficiency of the methods was assessed by pigment contents and profiles present in the extracts. Extraction of wet biomass by means of glass bead-assisted cell disruption using tetrahydrofuran yielded the highest amounts of lutein and
β
-carotene (622 ± 40 and 618 ± 32 µg g
−1
DW, respectively). Although acetone was slightly less efficient than tetrahydrofuran, it is preferable due to its lower costs and toxicity.
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•Tetraselmis sp. CTP4 is suitable for urban wastewater treatment.•Wastewater N and P were 100% removed in batch and continuous conditions.•Produced biomass displayed high protein and ...carbohydrate contents.•Aging cultures showed decreased protein and increased carbohydrate contents.•Cells grown in low saline media had low PUFA but high EPA content.
The ability of a recent isolate, Tetraselmis sp. CTP4, for nutrient removal from sewage effluents before and after the nitrification process under batch and continuous cultivation was studied. Biomass productivities in both wastewaters were similar under continuous conditions (0.343±0.053gL−1d−1) and nutrient uptake rates were maximal 31.4±0.4mgNL−1d−1 and 6.66±1.57mgP-PO43−L−1d−1 in WW before nitrification when cultivated in batch. Among batch treatments, cellular protein, carbohydrate and lipid levels shifted with aging cultures from 71.7±6.3 to 29.2±1.2%, 17.4±7.2 to 57.2±3.9% and 10.9±1.7 to 13.7±4.7%, respectively. In contrast, CTP4 cultivated continuously in Algal medium (control) showed lower biomass productivities (0.282gVSSL−1d−1) although improved lipid content (up to 20% lipids) in batch cultivation. Overall, Tetraselmis sp. CTP4 is promising for WW treatment as a replacement of the costly nitrification process, fixating more nutrients and providing a protein and carbohydrate-rich biomass as by-product.
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