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1.
Environ Technol ; : 1-13, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619982

RESUMEN

Microbial extracellular polymeric substances (EPS) have recently emerged as significant contributors in diverse biotechnological applications. Extracellular polymeric substances (EPS), produced by a Navicula salinicola strain, have been studied for potential applications in a specific heavy metal (lead (Pb II)) removal from wastewater. The optimisation of operational parameters, mainly pH, Pb and EPS concentrations, using the Box-Behnken design (BBD) was undertaken to enhance lead uptake. The higher Pb adsorption capacity reached 2211.029 mg/g. Hydroxyl, carbonyl, carboxyl, phosphoric, and sulfhydryl groups were identified quantitatively as potential sites for Pb adsorption. EPS exhibited a notable flocculation rate of 70.20% in kaolin clay at a concentration of 15 mg/L. They demonstrated an emulsifying activity greater than 88%, showcasing their versatile potential for both sedimentation processes and stabilising liquid-liquid systems. EPS could be excellent nonconventional renewable biopolymers for treating water and wastewater.

2.
Arch Microbiol ; 206(5): 218, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625565

RESUMEN

There is a great scientific curiosity to discover all environments sheltering microalgae, especially those with exceptional characteristics from coldest to hottest ones, the purpose remains to explore the potential of the native microalgae flora and the research for new bioactive compounds. This study aimed to isolate a polysaccharide-producing microalga from an extreme ecosystem and to evaluate its capacity to inhibit the α-D-glucosidase enzyme. Chlorella strain is isolated from hypersaline Lake in the Algerian desert. The exopolysaccharide extraction was performed by the concentration of free-cell supernatant in a rotary evaporator. The infrared analysis showed a characteristic footprint of carbohydrates with particular functional groups, such as sulfate. Gas chromatography-mass spectrometry has revealed a hetero-exopolysaccharide composed of galactose 35.75%, glucose 21.13%, xylose 16.81%, fructose 6.96%, arabinose 5.10%, and glucuronic acid 2.68%. The evaluation of the anti-hyperglycemic activity demonstrated a significant α-D-glucosidase inhibition of 80.94 ± 0.01% at 10 mg mL-1 with IC50 equal to 4.31 ± 0.20 mg mL-1. This study opens a vast prospect to use exopolysaccharides as natural nutraceutical or food additive.


Asunto(s)
Chlorella , Sulfatos , Ecosistema , Arabinosa , Glucosidasas
3.
Biotechnol Rep (Amst) ; 41: e00827, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38234329

RESUMEN

Fermentation of both microalgae and macroalgae is one of the most efficient methods of obtaining valuable value-added products due to the minimal environmental pollution and the availability of economic benefits, as algae do not require arable land and drift algae and algal bloom biomass are considered waste and must be recycled and their fermentation waste utilized. The compounds found in algae can be effectively used in the fuel, food, cosmetic, and pharmaceutical industries, depending on the type of fermentation used. Products such as methane and hydrogen can be produced by anaerobic digestion and dark fermentation of algae, and lactic acid and its polymers can be produced by lactic acid fermentation of algae. Article aims to provide an overview of the different types potential of micro- and macroalgae fermentation, the advantages and disadvantages of each type considered, and the economic feasibility of algal fermentation for the production of various value-added products.

4.
Enzyme Microb Technol ; 173: 110373, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38091836

RESUMEN

Despite being one of the first enzymes discovered in 1883, the determination of laccase activity remains a scientific challenge, and a barrier to the full use of laccase as a biocatalyst. Indeed, laccase, an oxidase of the blue multi-copper oxidases family, has a wide range of substrates including substituted phenols, aromatic amines and lignin-related compounds. Its one-electron mechanism requires only oxygen and releases water as a reaction product. These characteristics make laccase a biocatalyst of interest in many fields of applications including pulp and paper industry, biorefineries, food, textile, and pharmaceutical industries. But to fully envisage the use of laccase at an industrial scale, its activity must be reliably quantifiable on complex substrates and in complex matrices. This review aims to describe current and emerging methods for laccase activity assays and place them in the context of a potential industrial use of the enzyme.


Asunto(s)
Lacasa , Lignina , Lacasa/química , Lignina/química
5.
Bioengineered ; 15(1): 2294160, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38131141

RESUMEN

Microalgae are capable of generating numerous metabolites that possess notable biological activities and hold substantial promise for various industrial applications. Nevertheless, the taxonomic diversity of these photosynthetic microorganisms has not received thorough investigation. Using the 18S rRNA encoding gene, a recently discovered strain originating from the Tunisian coast (the governorate of Mahdia) was identified as a member of the Porphyridium genus. The growth response as well as the metabolite accumulation of Porphyridium sp. to different culture media (Pm, F/2, and Hemerick) was investigated over a period of 52 days. The highest biomass production was recorded with Pm medium (2 × 107 cell/mL). The apparent growth rates (µ) and the doubling time (Dt) were about 0.081 day-1 and 12.34 days, respectively. The highest chlorophyll a (0.678 ± 0.005 pg/cell), total carotenoids (0.18 ± 0.003 pg/cell), phycoerythrin (3.88 ± 0.003 pg/cell), and proteins (14.58 ± 0.35 pg/cell) contents were observed with F/2 medium. Cultivating Porphyridium sp. in both F/2 and Hemerick media yielded similar levels of starch accumulation. The Hemerick medium has proven to be the most suitable for the production of lipids (2.23% DW) and exopolysaccharides (5.41 ± 0.56 pg/cell).


Asunto(s)
Microalgas , Porphyridium , Porphyridium/genética , Porphyridium/metabolismo , Clorofila A/metabolismo , Almidón , Fotosíntesis , Biomasa , Microalgas/metabolismo
6.
Bioengineered ; 15(1): 2296257, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38153265

RESUMEN

With the aim to find new polysaccharides of rheological interest with innovated properties, rhamnofucans produced as exopolysaccharides (EPS) in a photobioreactor (PBR) and an airlift bioreactor (ABR) by the marine microalgae Glossomastix sp. RCC3707 and RCC3688 were fully studied. Chemical characterizations have been conducted (UHPLC - MS HR). Analyses by size-exclusion chromatography (SEC) coupled online with a multiangle light scattering detector (MALS) and a differential refractive index detector showed the presence of large structures with molar masses higher than 106 g.mol-1. The rheological studies of these EPS solutions, conducted at different concentrations and salinities, have evidenced interesting and rare behavior characteristic of weak and fragile hydrogels i.e. gel behavior with very low elastic moduli (between 10-2 and 10 Pa) and yield stresses (between 10-2 and 2 Pa) according to the EPS source, concentration, and salinity. These results were confirmed by diffusing wave spectroscopy. Finally, as one of potential application, solutions of EPS from Glossomastix sp. have evidenced very good properties as anti-settling stabilizers, using microcrystalline cellulose particles as model, studied by multiple light scattering (MLS) with utilization in cosmetic or food industry. Compared to alginate solution with same viscosity for which sedimentation is observed over few hours, microalgae EPS leads to a stable suspension over few days.


Asunto(s)
Microalgas , Polisacáridos/química , Alginatos , Fotobiorreactores , Polisacáridos Bacterianos
7.
Biotechnol Rep (Amst) ; 40: e00818, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38020727

RESUMEN

Biologically active compounds, including polysaccharides isolated from microalgae, have various properties. Although Nannochloropsis spp. have the potential to produce secondary metabolites important for biotechnology, only a small part of the research on these microalgae has focused on their ability to produce polysaccharide fractions. This study aims to evaluate the physicochemical growth factors of Nannochloropsis spp. microalgae, which ensure the maximum accumulation of polysaccharides, as well as to optimize the parameters of polysaccharide extraction. The optimal nutrient medium composition was selected to maximize biomass and polysaccharide accumulation. The significance of selecting the extraction module and extraction temperature regime, as well as the cultivation conditions (temperature and active acidity value) is emphasized. Important chemical components of polysaccharides responsible for their biological activity were identified.

8.
Bioengineered ; 14(1): 2254027, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37700452

RESUMEN

Exopolysaccharides (EPS) from the microalgae Porphyridium cruentum, Chrysotila dentata, Pavlova sp., Diacronema sp., Glossomastix sp., Phaeodactylum tricornutum, and Synechococcus sp. were isolated and depolymerized. First, EPS were submitted to a high pressure pre-treatment step, followed by a solid acid-catalyzed hydrolysis step carried out in a batch or recycle fixed-bed reactor, using a strong acidic cation-exchange resin. Twenty-eight different EPS forms were thus obtained. After characterization of their main structural features (weight- and number-averaged molecular weight, polydispersity index, sulfate and uronic acid contents), we investigated the structure-function relationship of their pro-collagen activity. We found that native microalgae EPS were able to inhibit until 27% of human matrix metalloproteinase-1 (MMP-1) activity while the depolymerized forms were able to enhance collagen production by two different human fibroblast lines, used as cell models due to their major role in dermal collagen biosynthesis. The most active EPS forms, obtained by depolymerization in the recycle fixed-bed reactor of D. ennorea and Glossomastix sp. EPS, led to 390% increase in collagen production. Finally, principal component (PCA) and Pearson analyses indicated that MMP-1 inhibition was strongly correlated to the sulfate group content of EPS whereas collagen production by fibroblasts was mostly related to their proportion of low molecular weight polysaccharides (<10 kDa). Uronic acid content of EPS was also shown essential but only if the size of EPS was reduced in the first place. Altogether, these results gave new insights of the dermo-cosmetic potential of microalgae EPS as well as the key parameters of their activity.


Six new and original EPS from microalgae were isolated.Microalgae EPS were depolymerized by high pressure/solid acid-catalyzed hydrolysis.Native EPS inhibited human matrix metalloproteinase-1.Depolymerized EPS highly stimulated collagen production by human dermal fibroblasts.Structure­function studies revealed that sulfate groups and MW of EPS were crucial.


Asunto(s)
Metaloproteinasa 1 de la Matriz , Microalgas , Humanos , Colágeno , Fibroblastos , Sulfatos
9.
Int J Biol Macromol ; 253(Pt 2): 126757, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37678695

RESUMEN

Marine algae are the most abundant resource in the marine environment and are still a promising source of bioactive compounds including hydrocolloids. This study contributes to the evaluation of the biological and biotechnological potentials of two water soluble polysaccharides, namely alginates (AHS) and fucoidan (FHS), extracted and purified from Halopteris scoparia, an abundant Tunisian brown macroalgae collected in Tunisia (Tabarka region). The total sugars, neutral monosaccharides, uronic acids, proteins, polyphenols, and sulfate groups contents were quantified for both fractions, as well as their functional groups and primary structural features by Fourier transform infrared spectroscopy, ionic and/or gas chromatography and nuclear magnetic resonance analyses. AHS and FHS showed significant anti-inflammatory (IC50 ≈ 1 mg/mL), anticoagulant (e.g., 27-61.7 for the activated partial thromboplastin time), antihyperglycemic (0.1-40 µg/mL) and anti-trypsin (IC50 ≈ 0.3-0.4 mg/mL) effects. FHS and a hydrolyzed fraction showed a very promising potential against herpes viruses (HSV-1) (IC50 < 28 µg/mL). Besides, AHS and two hydrolyzed fractions were able to stimulate the natural defenses of tomato seedlings, assessing their elicitor capacity, by increasing the activity of phenylalanine ammonia-lyase (66-422 %) but also significantly changing the polyphenol content in the leaves (121-243 %) and roots (30-104 %) of tomato plants.


Asunto(s)
Phaeophyceae , Scoparia , Algas Marinas , Algas Marinas/química , Agua/metabolismo , Polisacáridos/química , Phaeophyceae/química
10.
Mar Drugs ; 21(8)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37623721

RESUMEN

Phycobiliproteins are photosynthetic light-harvesting pigments isolated from microalgae with fluorescent, colorimetric and biological properties, making them a potential commodity in the pharmaceutical, cosmetic and food industries. Hence, improving their metabolic yield is of great interest. In this regard, the present review aimed, first, to provide a detailed and thorough overview of the optimization of culture media elements, as well as various physical parameters, to improve the large-scale manufacturing of such bioactive molecules. The second section of the review offers systematic, deep and detailed data about the current main features of phycobiliproteins. In the ultimate section, the health and nutritional claims related to these bioactive pigments, explaining their noticeable potential for biotechnological uses in various fields, are examined.


Asunto(s)
Microalgas , Biotecnología , Colorantes , Comercio , Ficobiliproteínas
11.
Sci Rep ; 13(1): 13561, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37604835

RESUMEN

Cyanobacterial exopolysaccharides (EPS) are potential candidates for the production of sustainable biopolymers. Although the bioactive and physicochemical properties of cyanobacterial-based EPS are attractive, their commercial exploitation is limited by the high production costs. Bioprospecting and characterizing novel EPS-producing strains for industrially relevant conditions is key to facilitate their implementation in various biotechnological applications and fields. In the present work, we selected twenty-five Portuguese cyanobacterial strains from a diverse taxonomic range (including some genera studied for the first time) to be grown in diel light and temperature, simulating the Portuguese climate conditions, and evaluated their growth performance and proximal composition of macronutrients. Synechocystis and Cyanobium genera, from marine and freshwater origin, were highlighted as fast-growing (0.1-0.2 g L-1 day-1) with distinct biomass composition. Synechocystis sp. LEGE 07367 and Chroococcales cyanobacterium LEGE 19970, showed a production of 0.3 and 0.4 g L-1 of released polysaccharides (RPS). These were found to be glucan-based polymers with high molecular weight and a low number of monosaccharides than usually reported for cyanobacterial EPS. In addition, the absence of known cyanotoxins in these two RPS producers was also confirmed. This work provides the initial steps for the development of cyanobacterial EPS bioprocesses under the Portuguese climate.


Asunto(s)
Bioprospección , Synechocystis , Portugal , Clima , Temperatura
12.
Int J Mol Sci ; 24(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37445700

RESUMEN

Mild cognitive impairment (MCI) is characterized by an abnormal decline in mental and cognitive function compared with normal cognitive aging. It is an underlying condition of Alzheimer's disease (AD), an irreversible neurodegenerative disease. In recent years, neuroinflammation has been investigated as a new leading target that contributes to MCI progression into AD. Understanding the mechanism underlying inflammatory processes involved in the early onset of the disease could help find a safe and effective way to diagnose and treat patients. In this article, we assessed over twenty different blood and cerebrospinal fluid (CSF) inflammatory biomarker concentrations with immunoassay methods in patients with MCI (mild cognitive impairment), non-impaired control (NIC), and serum healthy control (HC). We performed group comparisons and analyzed in-group correlations between the biomarkers. We included 107 participants (mean age: 64.7 ± 7.8, women: 58.9%). CSF osteopontin and YKL-40 were significantly increased in the MCI group, whereas serum C-reactive protein and interleukin-6 were significantly higher (p < 0.001) in the NIC group compared with the MCI and HC groups. Stronger correlations between interleukin-1ß and inflammasome markers were observed in the serum of the MCI group. We confirmed specific inflammatory activation in the central nervous system and interleukin-1ß pathway upregulation in the serum of the MCI cohort.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedades Neurodegenerativas , Humanos , Femenino , Persona de Mediana Edad , Anciano , Enfermedad de Alzheimer/diagnóstico , Interleucina-1beta , Disfunción Cognitiva/diagnóstico , Inflamación , Biomarcadores/líquido cefalorraquídeo , Progresión de la Enfermedad , Péptidos beta-Amiloides/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo
13.
Bioengineered ; 14(1): 228-244, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37455672

RESUMEN

Taken separately, a single sweet sorghum stem bioconversion process for bioethanol and biomethane production only leads to a partial conversion of organic matter. The direct fermentation of crushed whole stem coupled with the methanization of the subsequent solid residues in a two-stage process was experimented to improve energy bioconversion yield, efficiency, and profitability. The raw stalk calorific value was 17,144.17 kJ/kg DM. Fermentation step performed using Saccharomyces cerevisiae resulted in a bioconversion yield of 261.18 g Eth/kg DM, i.e. an energy recovery efficiency of 6921.27 kJ/kg DM. The methanogenic potentials were 279 and 256 LCH4/kg DM, respectively, for raw stem and fermentation residues, i.e. energy yields of 10,013.31 and 9187.84 kJ/kg DM, respectively. Coupling processes have significantly increased yield and made it possible to reach 13,309.57 kJ/kg DM, i.e. 77.63% of raw stem energy recovery yield, compared to 40.37% and 58.40%, respectively, for single fermentation and methanization processes.


Sweet sorghum stem is a viable feedstock source for efficient coproduction of ethanol and methaneSorghum stems calorific value determination revealed an energy potential of 17.15 MJ/kg DMEnergy recovery by single methanization yielded 18.03% more than ethanol fermentationCoupling processes has significantly increased energy recovery yield and profitability.


Asunto(s)
Sorghum , Fermentación , Sorghum/química , Etanol , Metano , Saccharomyces cerevisiae
14.
Molecules ; 28(12)2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37375426

RESUMEN

Here, we report work on developing an enzymatic process to improve the functionalities of industrial lignin. A kraft lignin sample prepared from marine pine was treated with the high-redox-potential laccase from the basidiomycete fungus Pycnoporus cinnabarinus at three different concentrations and pH conditions, and with and without the chemical mediator 1-hydroxybenzotriazole (HBT). Laccase activity was tested in the presence and absence of kraft lignin. The optimum pH of PciLac was initially 4.0 in the presence and absence of lignin, but at incubation times over 6 h, higher activities were found at pH 4.5 in the presence of lignin. Structural changes in lignin were investigated by Fourier-transform infrared spectroscopy (FTIR) with differential scanning calorimetry (DSC), and solvent-extractable fractions were analyzed using high-performance size-exclusion chromatography (HPSEC) and gas chromatography-mass spectrometry (GC-MS). The FTIR spectral data were analyzed with two successive multivariate series using principal component analysis (PCA) and ANOVA statistical analysis to identify the best conditions for the largest range of chemical modifications. DSC combined with modulated DSC (MDSC) revealed that the greatest effect on glass transition temperature (Tg) was obtained at 130 U g cm-1 and pH 4.5, with the laccase alone or combined with HBT. HPSEC data suggested that the laccase treatments led to concomitant phenomena of oligomerization and depolymerization, and GC-MS revealed that the reactivity of the extractable phenolic monomers depended on the conditions tested. This study demonstrates that P. cinnabarinus laccase can be used to modify marine pine kraft lignin, and that the set of analytical methods implemented here provides a valuable tool for screening enzymatic treatment conditions.


Asunto(s)
Lacasa , Polyporaceae , Lacasa/química , Lignina/química
15.
Mar Drugs ; 21(5)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37233495

RESUMEN

Alginates extracted from two Moroccan brown seaweeds and their derivatives were investigated for their ability to induce phenolic metabolism in the roots and leaves of tomato seedlings. Sodium alginates (ALSM and ALCM) were extracted from the brown seaweeds Sargassum muticum and Cystoseira myriophylloides, respectively. Low-molecular-weight alginates (OASM and OACM) were obtained after radical hydrolysis of the native alginates. Elicitation was carried out by foliar spraying 20 mL of aqueous solutions (1 g/L) on 45-day-old tomato seedlings. Elicitor capacities were evaluated by monitoring phenylalanine ammonia-lyase (PAL) activity, polyphenols, and lignin production in the roots and leaves after 0, 12, 24, 48, and 72 h of treatment. The molecular weights (Mw) of the different fractions were 202 kDa for ALSM, 76 kDa for ALCM, 19 kDa for OACM, and 3 kDa for OASM. FTIR analysis revealed that the structures of OACM and OASM did not change after oxidative degradation of the native alginates. These molecules showed their differential capacity to induce natural defenses in tomato seedlings by increasing PAL activity and through the accumulation of polyphenol and lignin content in the leaves and roots. The oxidative alginates (OASM and OACM) exhibited an effective induction of the key enzyme of phenolic metabolism (PAL) compared to the alginate polymers (ALSM and ALCM). These results suggest that low-molecular-weight alginates may be good candidates for stimulating the natural defenses of plants.


Asunto(s)
Phaeophyceae , Sargassum , Algas Marinas , Sargassum/química , Alginatos/química , Lignina/farmacología , Peso Molecular , Phaeophyceae/química , Algas Marinas/química , Estrés Oxidativo
16.
Polymers (Basel) ; 15(9)2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37177323

RESUMEN

Glucuronan is a polysaccharide composed of ß-(1,4)-linked d-glucuronic acids having intrinsic properties and biological activities recoverable in many fields of application. Currently, the description of Sinorhyzobium meliloti M5N1CS mutant bacterial strain as the sole source of glucuronan makes it relevant to the exploration of new microorganisms producing glucuronan. In this study, the Peteryoungia rosettifformans strain (Rhizobia), was identified as a wild producer of an exopolysaccharide (RhrBR46) related to glucuronan. Structural and biochemical features, using colorimetric assays, Fourier infrared spectroscopy, nuclear magnetic resonance, high pressure size exclusion chromatography coupled to multi-angle light laser scattering, and enzymatic assays allowed the characterization of a polyglucuronic acid, having a molecular mass (Mw¯) of 1.85 × 105 Da, and being partially O-acetylated at C-2 and/or C-3 positions. The concentration of Mg2+ ions in the cultivation medium has been shown to impact the structure of RhrBR46, by reducing drastically its Mw¯ (73%) and increasing its DA (10%). Comparative structural analyses between RhrBR46 and the glucuronan from Sinorhyzobium meliloti M5N1CS strain revealed differences in terms of molecular weight, degree of acetylation (DA), and the distribution of acetylation pattern. These structural divergences of RhrBR46 might contribute to singular properties or biological activities of RhrBR46, offering new perspectives of application.

17.
Materials (Basel) ; 16(6)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36984120

RESUMEN

Extrusion and hot compressing molding processes were used to create bio-polyethylene (BioPE) composites reinforced with argan byproducts (shell, pulp, and argan cake) as bio-fillers. The thermal stability of the composites wass analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Dynamical mechanical analysis and rheological testing were used to investigate their mechanical properties. The morphological results showed a good adhesion between the argan and BioPE matrix. More efficient mechanical properties have been distinguished in the case of argan byproduct-based composite. A higher Young's modulus was noted for all the biocomposites compared to pure BioPE. Thermal analysis revealed that the addition of bio-filler to polymer reduced decomposition temperatures. This study provides an ecological alternative for upgrading the valorization of abundant and underutilized Moroccan biomass. Furthermore, the possibility of using argan byproducts in composite manufacturing will help open up new markets for what is currently considered waste.

18.
Environ Technol ; : 1-12, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36952278

RESUMEN

Algae constitute a significant part of marine biodiversity. They represent a renewable source of bioactive metabolites from drug development and therapeutic fields. Fucoxanthin and ß-carotene from the brown macroalgae Halopteris scoparia, were extracted using conventional organic solvent extraction, then purified, to homogeneity, based on various chromatographic principles. Their effects on digestive enzymes and harmful bacteria were investigated. The capacities of both purified pigments to inhibit α-amylase and trypsin enzymes were evaluated. Purified fucoxanthin and ß-carotene exhibited interesting α-amylase inhibition activities, with IC50 of 300 and 500 µg/mL, respectively. Moreover, trypsin inhibition activities were detected using purified these two pigments. The antibacterial potential of the purified pigments was evaluated. ß-carotene showed to be a great antibacterial natural compound against gram-positive and gram-negative bacteria such as Listeria monocytogenes, Staphylococcus aureus and Salmonella enterica with Minimal Inhibitory Concentration (MIC) of about 0.225, 0.1125, 0.225 µg/mL, respectively. Those findings are in favor of the exploitation of H. scoparia pigments in therapeutic fields as an antidiabetic source directly by the inhibition of α-amylase and trypsin as well as antibacterial agents against gastrointestinal infections.

19.
Anal Biochem ; 667: 115080, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36775111

RESUMEN

Parachlamydia acanthamoebae and Simkania negevensis, two Chlamydia-like bacteria, have been recently recognized as emerging human respiratory pathogens. The prevalence and frequency of these bacteria in the environment and among atypical pneumonia patients are still underestimated by classical cultures, immunohistochemistry and serology which are non-specific, long and tedious methods. This study aims to develop a new duplex probe-based q-PCR assay for the simultaneous detection and quantification of P. acanthamoebae and S. negevensis. The selected hydrolysis probes displayed no cross-reaction with the closely related Chlamydia or the other tested waterborne pathogens. The assay achieved a large dynamic range for quantification (from 5 × 106 to 5 DNA copies/reaction). Efficiencies of FAM and JOE label probes weren't affected when they were combined. They were close to 100%, indicating the linear amplification. The application of this diagnostic tool resulted in 9/47 (19%) and 4/47 (8.5%) positive water samples for P. acanthamoebae and S. negevensis, respectively. P. acanthamoebae was also covered from 2/78 (2.5%) respiratory specimens and only one case (1/200 = 0.5%) of P. acanthamoebae and SARS-CoV-2 co-infection was noticed. While S. negevensis wasn't detected in clinical samples, the developed duplex q-PCR was shown to be an accurate, highly sensitive, and robust diagnostic tool for the detection and quantification of P. acanthamoebae and S. negevensis.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Reacción en Cadena de la Polimerasa/métodos , Prueba de COVID-19
20.
Bioresour Technol ; 370: 128536, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36581232

RESUMEN

Due to growing health concerns, the urban population is utterly inclined towards a healthy lifestyle and incorporated nutritional food supplements to lower common health risks. The ω-3 and ω-6 PUFAs consumption is increasing, hence alternative commercial production is essentially developed. The microbial source is an emerging platform to overcome the global demand for omega PUFAs. Marine oleaginous protist Aurantiochytrium sp. found a potential source to produce substantial DHA and SFA. The objective of the present research was to enhance the PUFA yield by optimizing maximum tolerable glucose concentration with a suitable nitrogen ratio (10:1). The maximum lipid and DHA yield and content were determined 4.30, 1.34 g/L, and 62.4, 33.49 % of total biomass and lipid at 30 g/L glucose respectively, which is one of among highest reported, however relative PUFA was maximum 46.97 % (DHA) in total lipid at 10 g/L glucose. Remaining 42-53.6 % SFA could be used for biodiesel.


Asunto(s)
Ácidos Grasos Omega-3 , Estramenopilos , Ácidos Docosahexaenoicos , Ácidos Grasos Insaturados , Suplementos Dietéticos , Glucosa , Ácidos Grasos
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