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1.
Phytomedicine ; 128: 155536, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38513379

RESUMEN

BACKGROUND: Lung cancer, a chronic and heterogeneous disease, is the leading cause of cancer-related death on a global scale. Presently, despite a variety of available treatments, their effectiveness is limited, often resulting in considerable toxicity and adverse effects. Additionally, the development of chemoresistance in cancer cells poses a challenge. Trilobolide-6-O-isobutyrate (TBB), a natural sesquiterpene lactone extracted from Sphagneticola trilobata, has exhibited antitumor effects. Its pharmacological properties in NSCLC lung cancer, however, have not been explored. PURPOSE: This study evaluated the impact of TBB on the A549 and NCI-H460 tumor cell lines in vitro, examining its antiproliferative properties and initial mechanisms of cell death. METHODS: TBB, obtained at 98 % purity from S. trilobata leaves, was characterized using chromatographic techniques. Subsequently, its impact on inhibiting tumor cell proliferation in vitro, TBB-induced cytotoxicity in LLC-MK2, THP-1, AMJ2-C11 cells, as well as its effects on sheep erythrocytes, and the underlying mechanisms of cell death, were assessed. RESULTS: In silico predictions have shown promising drug-likeness potential for TBB, indicating high oral bioavailability and intestinal absorption. Treatment of A549 and NCI-H460 human tumor cells with TBB demonstrated a direct impact, inducing significant morphological and structural alterations. TBB also reduced migratory capacity without causing toxicity at lower concentrations to LLC-MK2, THP-1 and AMJ2-C11 cell lines. This antiproliferative effect correlated with elevated oxidative stress, characterized by increased levels of ROS, superoxide anion radicals and NO, accompanied by a decrease in antioxidant markers: SOD and GSH. TBB-stress-induced led to changes in cell metabolism, fostering the accumulation of lipid droplets and autophagic vacuoles. Stress also resulted in compromised mitochondrial integrity, a crucial aspect of cellular function. Additionally, TBB prompted apoptosis-like cell death through activation of caspase 3/7 stressors. CONCLUSION: These findings underscore the potential of TBB as a promising candidate for future studies and suggest its viability as an additional component in the development of novel anticancer drugs prototypes.


Asunto(s)
Butiratos , Neoplasias Pulmonares , Sesquiterpenos , Sesquiterpenos/farmacología , Butiratos/farmacología , Tracheophyta/química , Línea Celular Tumoral , Neoplasias Pulmonares/tratamiento farmacológico , Humanos , Células A549 , Células THP-1 , Pruebas de Toxicidad , Movimiento Celular/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Animales
2.
Biomed Pharmacother ; 170: 115979, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38061138

RESUMEN

Lung cancer is one of the leading causes of cancer-related deaths in men and women worldwide. Current treatments have limited efficacy, cause significant side effects, and cells can develop drug resistance. New therapeutic strategies are needed to discover alternative anticancer agents with high efficacy and low-toxicity. TMBP, a biphenyl obtained by laccase-biotransformation of 2,6-dimethoxyphenol, possesses antitumor activity against A549 adenocarcinoma cells. Without causing damage to sheep erythrocytes and mouse peritoneal macrophages of BALB/c mice. In addition to being classified as a good oral drug according to in-silico studies. This study evaluated the in-vitro cytotoxic effect of TMBP on lung-cancer cell-line NCI-H460 and reports mechanisms on immunomodulation and cell death. TMBP treatment (12.5-200 µM) inhibited cell proliferation at 24, 48, and 72 h. After 24-h treatment, TMBP at IC50 (154 µM) induced various morphological and ultrastructural changes in NCI-H460, reduced migration and immunofluorescence staining of N-cadherin and ß-catenin, induced increased reactive oxygen species and nitric oxide with reduced superoxide radical-anion, increased superoxide dismutase activity and reduced glutathione reductase. Treatment also caused metabolic stress, reduced glucose-uptake, intracellular lactate dehydrogenase and lactate levels, mitochondrial depolarization, increased lipid droplets, and autophagic vacuoles. TMBP induced cell-cycle arrest in the G2/M phase, death by apoptosis, increased caspase-3/7, and reduced STAT-3 immunofluorescence staining. The anticancer effect was accompanied by decreasing PI3K, AKT, ARG-1, and NF-κB levels, and increasing iNOS. These results suggest its potential as a candidate for use in future lung anticancer drug design studies.


Asunto(s)
Antineoplásicos , Neoplasias Pulmonares , Femenino , Humanos , Animales , Ratones , Ovinos , Neoplasias Pulmonares/patología , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Línea Celular Tumoral , Apoptosis , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proliferación Celular , Estrés Oxidativo , Estrés Fisiológico
3.
Sci Rep ; 13(1): 6928, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37117253

RESUMEN

Available treatments for leishmaniasis have been widely used since the 1940s but come at a high cost, variable efficacy, high toxicity, and adverse side-effects. 3,3',5,5'-Tetramethoxy-biphenyl-4,4'-diol (TMBP) was synthesized through laccase-catalysis of 2,6-dimethoxyphenol and displayed antioxidant and anticancer activity, and is considered a potential drug candidate. Thus, this study aimed to evaluate the anti-leishmanial effect of TMBP against promastigote and amastigote forms of Leishmania (L.) amazonensis and investigated the mechanisms involved in parasite death. TMBP treatment inhibited the proliferation (IC50 0.62-0.86 µM) and induced the death of promastigote forms by generating reactive oxygen species and mitochondrial dysfunction. In intracellular amastigotes, TMBP reduced the percentage of infected macrophages, being 62.7 times more selective to the parasite (CC50 53.93 µM). TMBP did not hemolyze sheep erythrocytes; indicative of low cytotoxicity. Additionally, molecular docking analysis on two enzyme targets of L. amazonensis: trypanothione reductase (TR) and leishmanolysin (Gp63), suggested that the hydroxyl group could be a pharmacophoric group due to its binding affinity by hydrogen bonds with residues at the active site of both enzymes. TMBP was more selective to the Gp63 target than TR. This is the first report that TMBP is a promising compound to act as an anti-leishmanial agent.


Asunto(s)
Antiprotozoarios , Leishmania mexicana , Leishmania , Animales , Ovinos , Ratones , Simulación del Acoplamiento Molecular , Antiprotozoarios/farmacología , Antiprotozoarios/química , Ratones Endogámicos BALB C
4.
Sci Rep ; 12(1): 19384, 2022 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-36371484

RESUMEN

The present study proposes the production of vinegars from pineapple processing residues as an eco-friendly strategy for adding value and economic strengthening of the production chain. Pineapple pulp and peel wines were produced and acetificated to vinegar by wild strains of acetic bacteria using Orlean's method (traditional system) followed by enrichment with leaf extract of Red-Jambo, Syzygium malaccense. Appreciable phenolic contents and antioxidant potential were found in pulp and peel vinegars with the added leaf extract. Catechin, epicatechin and caffeic, p-coumaric, ferulic, and gallic acids were the main phenolic compounds found in peel vinegar. The enrichment of the vinegar with the extract promoted an increase in the content of polyphenols (443.6-337.3 mg GAE/L) and antioxidant activity. Peel wines presented higher luminosity (L*) and higher saturation index (C*), and their color tended more toward yellow than pulp wines. Acetification reduced the saturation index (C*) and led to the intensification of the hue angle in the peels vinegar. Each type of pineapple vinegar produced showed biocidal activity against different bacteria and yeast, and the addition of leaf extract potentiated the antimicrobial activity of peel vinegar, especially against Staphalococcus aureus. The vinegars developed could find an attractive market niche in the food sector.


Asunto(s)
Ananas , Syzygium , Vino , Ácido Acético/química , Ananas/química , Vino/análisis , Fenoles/química , Antioxidantes/química , Saccharomyces cerevisiae , Extractos Vegetales
5.
Cell Biochem Funct ; 40(7): 773-783, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36111697

RESUMEN

Obesity is associated with other diseases such as diabetes and cancer. Botryosphaeran, a fungal (1→3)(1→6)-ß-d-glucan, is described to present antimutagenic, hypoglycemic, hypocholesterolemic, and antitumor activities when administered by gavage over 15 days in rats and mice. Thus, the present study aims to analyze the metabolic effects of Botryosphaeran (12 mg/kg body weight/day) treatment over 30 days in obese Wistar male rats. Obesity was induced in the rats by a high-fat/high-sugar diet for 8 weeks. Control rats received a standard diet. On the 5th week, Botryosphaeran treatment commenced. Groups: control, obese, and obese+Botryosphaeran 30 days. In the 8th week, obesity was characterized. Feed intake, glucose and lipid profiles, glucose tolerance, and insulin sensitivity were analyzed. Obese rats showed accumulation of visceral adipose tissue, reduction of muscle mass, glucose intolerance, insulin resistance, hyperglycemia, and dyslipidemia. Botryosphaeran effectively reduced weight gains and the accumulation of retroperitoneal adipose tissue, corrected the levels of glucose, triglycerides, and very low-density lipoprotein-cholestrol, and improved insulin sensitivity. Treatment for 30 days was effective in maintaining the beneficial effects demonstrated by this ß-glucan when administered for 15 days without promoting side effects. Treatment with (1→3)(1→6)-ß- d-glucan presented anti-obesogenic and beneficial metabolic effects in Wistar rats; important for the treatment of obesity and its comorbidities.


Asunto(s)
Resistencia a la Insulina , beta-Glucanos , Animales , Glucemia , Dieta Alta en Grasa , Glucanos/farmacología , Glucosa , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Insulina , Lipoproteínas LDL , Masculino , Ratones , Obesidad/metabolismo , Ratas , Ratas Wistar , Azúcares , Triglicéridos/metabolismo , beta-Glucanos/farmacología
6.
Biomacromolecules ; 23(10): 4041-4052, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36173245

RESUMEN

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-ß-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Aciclovir/farmacología , Aciclovir/uso terapéutico , Antivirales/farmacología , Glucanos/farmacología , Herpes Simple/tratamiento farmacológico , Humanos
7.
Cell Biochem Funct ; 40(6): 578-588, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35788958

RESUMEN

Several biological activities of the fungal exopolysaccharide (1 → 3)(1 → 6)-ß-d-glucan (botryosphaeran) have been described in the literature, but its effects on inflammation have not been evaluated. This study aimed to investigate the action of botryosphaeran on experimental mice models of carrageenan-induced acute pleurisy and acute paw edema, and complete Freund's adjuvant-induced persistent paw edema. All botryosphaeran doses tested (1.0, 2.5, 5.0, and 10.0 mg/kg birth weight [b.w.], orally administered) reduced leukocyte recruitment, nitric oxide (NO) levels, and protein extravasation in the pleural cavity. Botryosphaeran (5 mg/kg b.w.) did not diminish edema and mechanical hyperalgesia in the paw within 4 h; however, cold allodynia was alleviated within the first 2 h. In the persistent paw inflammation model, the effects of daily oral administration of botryosphaeran (5 mg/kg b.w.) were evaluated over 3 and 7 days. The fungal ß-glucan significantly reduced the levels of the cytokines, tumor necrosis factor(TNF)-α, interleukin (IL)-6), and IL-10, in the paw homogenates in both protocols, while paw edema and the levels of advanced oxidation protein products (AOPP) only diminished on Day 7. No effect in mechanical hyperalgesia was observed. Oral treatment for 3 or 7 days also decreased the plasma levels of NO, AOPP, TNF-α, and IL-10. On Day 7, the number of leukocytes in the blood was also reduced by this treatment. Importantly, botryosphaeran did not induce inflammation in mice when administered alone over 7 days. This study demonstrated the anti-inflammatory and antinociceptive potential of botryosphaeran in these experimental models, making this fungal ß-glucan a new possibility for complementary treating acute and chronic inflammation.


Asunto(s)
Hiperalgesia , beta-Glucanos , Administración Oral , Productos Avanzados de Oxidación de Proteínas/metabolismo , Animales , Edema/inducido químicamente , Edema/tratamiento farmacológico , Edema/patología , Glucanos/efectos adversos , Glucanos/farmacología , Glucanos/uso terapéutico , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Interleucina-10 , Leucocitos/patología , Ratones , Nocicepción , beta-Glucanos/efectos adversos , beta-Glucanos/farmacología , beta-Glucanos/uso terapéutico
8.
J Toxicol Environ Health A ; 85(13): 521-537, 2022 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-35255775

RESUMEN

Breast cancer is the most common cancer worldwide among the female population. The fungal exopolysaccharide botryosphaeran is a (1→3)(1→6)-ß-D-glucan with limited solubility in water that can be promoted through carboxymethylation. Thus, the aim of this study was to examine in-vitro anticancer effects of carboxymethylated-botryosphaeran (CM-BOT) on breast cancer MCF-7 cells cultivated in multicellular tumor spheroids (MCTS). CM-BOT (≥ 600 µ/ml) decreased the viability (resazurin assay) of MCF-7 grown in monolayers after 24 hr incubation. Although CM-BOT did not markedly alter viability of MCTS in the resazurin assay after 24, 48 or 72 hr, CM-BOT ≥ 600 µg/ml produced cell-death by apoptosis after 72 hr utilizing the triple staining assay and labeling dead cells with propidium iodide, which can also be visualized on the architecture of MCTS. CM-BOT (1000 µg/ml) inhibited cell proliferation, which resulted in MCTSs with smaller diameters than controls. CM-BOT at all concentrations examined decreased the ability of MCF-7 to form colonies and to migrate in the extracellular matrix. This is the first report using MCTS-architecture to study anti-tumor effects of ß-glucans. Our findings are important in the search for compounds for use in breast cancer therapy, or as adjuvants in reducing the adverse effects of mammary tumor chemotherapy.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Glucanos/farmacología , Glucanos/uso terapéutico , Humanos , Células MCF-7 , Esferoides Celulares
9.
Cell Biochem Funct ; 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35229356

RESUMEN

Botryosphaeran, a (1→3)(1→6)-ß-d-glucan, presents several beneficial activities, such as antiproliferative, hypoglycemic and antitumoural activities. This study evaluated the effects of botryosphaeran on oxidative stress, inflammation and metabolic activities in Walker-256 tumour-bearing non-obese and obese rats. Wistars rats were divided into four groups: control tumour (CT); control tumour + botryosphaeran (CTB); obese tumour (OT), and obese tumour + botryosphaeran (OTB). In ninth week, obese and non-obese rats were inoculated with 1 × 107 Walker-256 tumour cells and treated with botryosphaeran (30 mg/kg/d for 15 days). In 11th week, the following parameters were evaluated glycogen, glucose and lactate levels, pro-oxidant (TBARS) and antioxidant markers (superoxide dismutase [SOD]; catalase [CAT]; glutathione-S-transferase [GST]; reduced glutathione [GSH]; vitamin C) and cytokines. Obesity presented oxidative stress and inflammation, as demonstrated by high levels of TBARS, SOD and TNF-α, and lower levels of CAT, GSH and interleukin-10 (IL-10). Botryosphaeran significantly decreased TBARS and TNF-α and increased GST, GSH, vitamin C and IL-10 in the liver; increased SOD and vitamin C in tumour tissue; decreased TBARS in adipose tissue, and notably decreased the levels of glycogen and lactate in the tumour of CTB rats. Botryosphaeran promoted significant antioxidant, anti-inflammatory, and beneficial metabolic effects in Walker-256 tumour-bearing non-obese and obese rats, which contributed to its antitumour activity.

10.
Appl Biochem Biotechnol ; 194(10): 4348-4361, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35146637

RESUMEN

The oxidation process of 2,6-dimethoxyphenol (2,6-DMP) by laccase from Botryosphaeria rhodina MAMB-05 and the corresponding enzyme-mediator systems was studied using cyclic voltammetry (CV). The enzyme was classified as a high oxidation potential laccase (> 0.70) V vs. NHE) based on its Redox potential at different pHs. The cyclic voltammograms for 2,6-DMP (- 58.7 mV pH-1) showed that its oxidation potential decreased more significantly compared to the enzyme (- 50.2 mV pH-1) by varying the pH. The 2,2'-azino-bis[3-ethyl-benzothiazoline-6-sulfonic acid] diammonium salt (ABTS) and 2,2,6,6-tetramethylpiperidine 1-oxyl radical (TEMPO) mediators were effectively oxidized by laccase from B. rhodina MAMB-05. The influence of laccase on the comproportionation of ABTS and the ionic step of the oxidation of TEMPO was also studied using CV. A higher potential difference was observed between laccase and the substrate, and correlated with higher enzyme activity. For the laccase-mediator systems, there was no clear correlation of potential difference between laccase and mediators with enzyme activity towards 2,6-DMP. This observation suggests that there are other limiting parameters for enzyme activity despite Redox potential difference, especially during ionic steps of the mechanism.


Asunto(s)
Electrones , Lacasa , Benzotiazoles , Catálisis , Lacasa/metabolismo , Oxidación-Reducción , Pirogalol/análogos & derivados , Ácidos Sulfónicos
11.
Chem Biol Interact ; 351: 109713, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34699765

RESUMEN

Leishmaniasis is an infectious-parasitic disease caused by the protozoan Leishmania spp. The available treatments are based upon expensive drugs bearing adverse side-effects. The search for new therapeutic alternatives that present a more effective action without causing adverse effects to the patient is therefore important. The objective of this study was to evaluate the in vitro effect of botryosphaeran, a (1 â†’ 3)(1 â†’ 6)-ß-D-glucan, on the promastigote and intracellular amastigote forms of Leishmania amazonensis. The direct activity of botryosphaeran on promastigote forms was evaluated in vitro and inhibited proliferation, the IC50 7 µg/mL in 48 h was calculated. After 48 h treatment, botryosphaeran induced nitric oxide production (NO), caused mitochondrial membrane hyperpolarization, increased reactive oxygen species (ROS), and accumulation of lipid vesicles in promastigotes, resulting in apoptosis, necrosis and autophagy, and was accompanied by morphological and ultrastructural changes. The range of concentrations used did not alter the viability of peritoneal macrophages from BALB/c mice and erythrocytes of sheep. Botryosphaeran was able to reduce the number of infected macrophages and the number of amastigotes per macrophage at 12.5 µg/mL (50.75% ± 6.48), 25 µg/mL (55.66% ± 3.93) and 50 µg/mL (72.9% ± 6.98), and IC50 9.3 µg/mL (±0.66) for intracellular amastigotes forms. The leishmanicidal effect was due to activation of NF-κB and promoted an increase in pro-inflammatory cytokines (TNF-α and IL-6), iNOS and microbial-derived ROS and NO, in addition to decreasing the levels of SOD. Based upon the data obtained, we infer that botryosphaeran exerted an active leishmanicidal and immunomodulatory effect, acting on promastigotes through autophagic, apoptotic and necrosis processes, and in the intracellular amastigote form, through the action of ROS and NO.


Asunto(s)
Apoptosis/efectos de los fármacos , Glucanos/farmacología , Factores Inmunológicos/farmacología , Leishmania/efectos de los fármacos , FN-kappa B/metabolismo , Tripanocidas/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Interleucina-6/metabolismo , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/microbiología , Masculino , Ratones Endogámicos BALB C , Necrosis/inducido químicamente , Óxido Nítrico Sintasa de Tipo II/metabolismo , Estrés Oxidativo/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
12.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34681671

RESUMEN

The infection of mammalian cells by enveloped viruses is triggered by the interaction of viral envelope glycoproteins with the glycosaminoglycan, heparan sulfate. By mimicking this carbohydrate, some anionic polysaccharides can block this interaction and inhibit viral entry and infection. As heparan sulfate carries both carboxyl and sulfate groups, this work focused on the derivatization of a (1→3)(1→6)-ß-D-glucan, botryosphaeran, with these negatively-charged groups in an attempt to improve its antiviral activity. Carboxyl and sulfonate groups were introduced by carboxymethylation and sulfonylation reactions, respectively. Three derivatives with the same degree of carboxymethylation (0.9) and different degrees of sulfonation (0.1; 0.2; 0.4) were obtained. All derivatives were chemically characterized and evaluated for their antiviral activity against herpes (HSV-1, strains KOS and AR) and dengue (DENV-2) viruses. Carboxymethylated botryosphaeran did not inhibit the viruses, while all sulfonated-carboxymethylated derivatives were able to inhibit HSV-1. DENV-2 was inhibited only by one of these derivatives with an intermediate degree of sulfonation (0.2), demonstrating that the dengue virus is more resistant to anionic ß-D-glucans than the Herpes simplex virus. By comparison with a previous study on the antiviral activity of sulfonated botryosphaerans, we conclude that the presence of carboxymethyl groups might have a detrimental effect on antiviral activity.


Asunto(s)
Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , Herpesviridae/efectos de los fármacos , Ácidos Sulfónicos/química , beta-Glucanos/química , Animales , Antivirales/química , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Virus del Dengue/fisiología , Glucanos/química , Glucanos/farmacología , Herpesviridae/fisiología , Metilación , Células Vero , Internalización del Virus/efectos de los fármacos , beta-Glucanos/farmacología
13.
Sci Rep ; 11(1): 20550, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34654845

RESUMEN

Flour from Pereskia aculeata leaf and green banana were used as ingredients in the formulation of a cereal bar with added Lactobacillus acidophilus LA02-ID-1688. Encapsulation in a calcium-alginate hydrogel reinforced with magnesium hydroxide was used as a strategy to protect the probiotic cells under gastrointestinal conditions and to prolong shelf-life. The results are relevant especially for maintaining cell viability during shelf-life; a challenge for the food industry in relation to dry probiotic products. Encapsulation promoted the protection of probiotic cells in simulated gastric and intestinal conditions, allowing the maintenance of high viable cell counts (> 10 log CFU, colony forming unit). Encapsulation also contributed to cellular protection under extreme temperature conditions, with reductions of cell viability of < 1 logarithmic cycle when the capsules were subjected to 55ºC/10 min. Even at 75ºC/10 min, encapsulation protected the probiotic cells 3-times greater than the free-cells. The food bar proved to be rich in dietary fiber (19 g 100 g-1), lipids (12.63 g 100 g-1) and showed an appreciable protein content (5.44 g 100 g-1). A high viable probiotic cell count on storage over 120 days (12.54 log CFU) was observed, maintaining a probiotic survival rate > 90% and viability levels sufficient to promote health benefits.


Asunto(s)
Cactaceae/química , Encapsulación Celular , Alimentos Funcionales/microbiología , Lactobacillus acidophilus , Probióticos , Alginatos , Supervivencia Celular , Chocolate , Alimentos Funcionales/análisis , Hidrogeles , Hidróxido de Magnesio , Musa
14.
J Hazard Mater ; 420: 126598, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34274805

RESUMEN

Two biomass types of Botryosphaeria rhodina MAMB-05 (VMSM and M3) were evaluated to determine their effectiveness in removing Ag(I) ions from synthetic solutions. Both biomass types obtained good results in the biosorption process with maximum biosorption capacities (qm) for the Langmuir model of 34.67 and 39.23 mg Ag(I)/g dry biomass for M3 and VMSM, respectively. The biomass was characterized by X-ray microfluorescence and Fourier-transform-infrared spectroscopy (FT-IR). After the biosorption process, the mechanisms involved in biosorption were studied by FT-IR, X-ray diffraction (XRD), Field Emission Scanning Microscopy/Energy Dispersive X-ray Analysis (FESEM/EDX) and Ultraviolet-Visible Spectrophotometry. The results demonstrated the participation of various mechanisms in the retention of silver on biomass (bioadsorption, complexation, ion exchange, covalent bonding) that resulted in the formation of silver chloride nanoparticles (AgCl-NPs) and silver nanoparticles (AgNPs). The sizes of AgCl-NPs (chlorargyrite) according to the Debye-Scherrer equation were 19.29 nm (VMSM biomass) and 24.9 nm for the M3 type. For AgNPs the crystal size was between 1.5 and 0.8 nm for VMSM and M3 respectively. Furthermore, it was found that an undetermined fraction of the silver nanoparticles after biosorption remained in solution, which could be advantageous for their recovery.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos , Ascomicetos , Biomasa , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
15.
Enzyme Microb Technol ; 147: 109780, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33992403

RESUMEN

Lignin is an abundant natural plant aromatic biopolymer containing various functional groups that can be exploited for activating lignin for potential commercial applications. Applications are hindered due to the presence of a high content of methyl/methoxyl groups that affects reactiveness. Various chemical and enzymatic approaches have been investigated to increase the functionality in transforming lignin. Among these is demethylation/demethoxylation, which increases the potential numbers of vicinal hydroxyl groups for applications as phenol-formaldehyde resins. Although the chemical route to lignin demethylation is well-studied, the biological route is still poorly explored. Bacteria and fungi have the ability to demethylate lignin and lignin-related compounds. Considering that appropriate microorganisms possess the biochemical machinery to demethylate lignin by cleaving O-methyl groups liberating methanol, and modify lignin by increasing the vicinal diol content that allows lignin to substitute for phenol in organic polymer syntheses. Certain bacteria through the actions of specific O-demethylases can modify various lignin-related compounds generating vicinal diols and liberating methanol or formaldehyde as end-products. The enzymes include: cytochrome P450-aryl-O-demethylase, monooxygenase, veratrate 3-O-demethylase, DDVA O-demethylase (LigX; lignin-related biphenyl 5,5'-dehydrodivanillate (DDVA)), vanillate O-demethylase, syringate O-demethylase, and tetrahydrofolate-dependent-O-demethylase. Although, the fungal counterparts have not been investigated in depth as in bacteria, O-demethylases, nevertheless, have been reported in demethylating various lignin substrates providing evidence of a fungal enzyme system. Few fungi appear to have the ability to secrete O-demethylases. The fungi can mediate lignin demethylation enzymatically (laccase, lignin peroxidase, manganese peroxidase, O-demethylase), or non-enzymatically in brown-rot fungi through the Fenton reaction. This review discusses details on the aspects of microbial (bacterial and fungal) demethylation of lignins and lignin-model compounds and provides evidence of enzymes identified as specific O-demethylases involved in demethylation.


Asunto(s)
Lacasa , Lignina , Desmetilación , Hongos/metabolismo , Lignina/metabolismo , Oxidación-Reducción
16.
Int J Biol Macromol ; 183: 316-330, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-33930443

RESUMEN

A hydrogel containing exocellular (1 → 6)-ß-D-glucan (lasiodiplodan, LAS) was developed and its wound healing potential was evaluated. ß-Glucans have attracted much interest by the cosmetic industry sector because of their bioactive and functional properties and in promoting skin health. In the present work an ß-glucan was studied as a healing biomaterial that has not hitherto been reported in the scientific literature. LAS produced by the ascomycete Lasiodiplodia theobromae MMPI was used in the formulation of a healing hydrogel. Physicochemical and microbiological quality parameters, antioxidant potential and stability of the formulation was evaluated. FTIR, thermal analysis and SEM techniques were also employed in the characterization. Wistar rats were used as a biological model to investigate the wound healing potential. Histological analyses of cutaneous tissue from the dorsal region were conducted after 4, 7, 10 and 14 days of treatment, and evaluated re-epithelialization, cell proliferation and collagen production. Physicochemical stability, microbiological quality and antioxidant potential, especially in relation to its ability to scavenge hydroxyl radicals were found. The hydrogel stimulated cell re-epithelialization and proliferation during all days of the treatment, and stimulated an increase of collagen fibers. Lasiodiplodan showed immunomodulatory activity in wound healing and this biomacromolecule could be an alternative compound in wound care.


Asunto(s)
Colágeno/química , Glucanos/química , Hidrogeles/química , Hidrogeles/farmacología , Polisacáridos/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Ratas
17.
Int J Biol Macromol ; 177: 176-203, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33609583

RESUMEN

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Factors increasing the risks for CVD development are related to obesity, diabetes, high blood cholesterol, high blood pressure and lifestyle. CVD risk factors may be treated with appropriate drugs, but prolonged can use cause undesirable side-effects. Among the natural products used in complementary and alternative medicines, are the ß-ᴅ-glucans; biopolymers found in foods (cereals, mushrooms), and can easily be produced by microbial fermentation. Independent of source, ß-glucans of the mixed-linked types [(1 → 3)(1 → 6)-ß-ᴅ-glucans - fungal, and (1 → 3)(1 → 4)-ß-ᴅ-glucans - cereal] have widely been studied because of their biological activities, and have demonstrated cardiovascular protective effects. In this review, we discuss the roles of ß-ᴅ-glucans in various pathophysiological conditions that lead to CVDs including obesity, dyslipidemia, hyperglycemia, oxidative stress, hypertension, atherosclerosis and stroke. The ß-glucans from all of the sources cited demonstrated potential hypoglycemic, hypocholesterolemic and anti-obesogenicity activities, reduced hypertension and ameliorated the atherosclerosis condition. More recently, ß-glucans are recognized as possessing prebiotic properties that modulate the gut microbiome and impact on the health benefits including cardiovascular. Overall, all the studies investigated unequivocally demonstrated the dietary benefits of consuming ß-glucans regardless of source, thus constituting a promising panaceutical approach to reduce CVD risk factors.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , beta-Glucanos/farmacología , beta-Glucanos/uso terapéutico , Animales , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/uso terapéutico , Anticolesterolemiantes/farmacología , Anticolesterolemiantes/uso terapéutico , Fermentación/efectos de los fármacos , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico
18.
Mikrochim Acta ; 188(1): 28, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33404780

RESUMEN

A photoelectrochemical biosensing strategy for the highly sensitive detection of the flavonoid rutin was developed by synergizing the photoelectrocatalytic properties of hematite (α-Fe2O3) decorated with palladium nanoparticles (PdNPs) and the biocatalysis towards laccase-based reactions. The integration of α-Fe2O3.PdNPs with a polyphenol oxidase as a biorecognition element yields a novel biosensing platform. Under visible light irradiation, the photoactive biocomposite can generate a stable photocurrent, which was found to be directly dependent upon the concentration of rutin. Under the optimal experimental conditions, the cathodic photocurrent, measured at 0.33 V vs. Ag/AgCl, from the square-wave voltammograms presented a linear dependence on the rutin concentration within the range of 0.008-30.0 × 10-8 mol L-1 (sensitivity: 1.7 µA·(× 10-8 M-1)·cm-2), with an experimental detection limit (S/N = 3) of 8.4 × 10-11 mol L-1. The proposed biosensor device presented good selectivity towards rutin in the presence of various organic compounds and inorganic ions, demonstrating the potential application of this biosensing platform in complex matrices. This bioanalytical device also exhibited excellent operational and analytical properties, such as intra-day (standard deviation, SD = 0.21%) and inter-day (SD = 1.30%) repeatability, and long storage stability (SD = 2.80% over 30 days).Graphical abstract.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Compuestos Férricos/química , Rutina/orina , Adulto , Enzimas Inmovilizadas/química , Compuestos Férricos/efectos de la radiación , Humanos , Lacasa/química , Luz , Límite de Detección , Masculino , Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Paladio/química , Paladio/efectos de la radiación , Procesos Fotoquímicos , Té/química , Vino/análisis , Adulto Joven
19.
Nutr Cancer ; 73(7): 1175-1192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32643421

RESUMEN

Studies demonstrate that obesity can increase tumor development. Botryosphaeran, a fungal (1→3)(1→6)-ß-D-glucan, presents antimutagenic, antiproliferative and pro-apoptotic activities. This study evaluated the effects of botryosphaeran on tumor development and metabolic and hematological parameters in tumor-bearing obese and non-obese rats. Obesity was induced by a high-fat and high-sugar diet, while control rats received standard diet and water without sugar for 10 weeks. On 8th-week, Walker-256 tumor cells were inoculated in the rats, and treatment with botryosphaeran (12 mg/Kg b.w.) started. Groups:control tumor-CT, control tumor botryosphaeran-CTB, obese tumor-OT and obese tumor botryosphaeran-OTB. On 10th-week, tumor development, cachexia, metabolic and hematological parameters were analyzed. Tumor development and cachexia were significantly higher in the OT group compared to the CT group, and botryosphaeran attenuated these parameters. OT rats presented accumulation of adipose tissue, reduced muscle mass, glucose intolerance, insulin resistance, hyperglycemia, anemia, leukocytosis, and thrombocytopenia. Botryosphaeran corrected insulin resistance and hyperglycemia, modulated cholesterol levels, and increased leukocyte and lymphocytes in obese rats, which can be attributable to an inflammatory response against the Walker-256 tumor, contributing to a lower tumor development. Our data demonstrated that botryosphaeran was effective in attenuating tumor growth and in improving the metabolic and hematological profiles of the tumor-bearing rats, demonstrating its potential role in the cancer's management.


Asunto(s)
Caquexia , Neoplasias , Animales , Caquexia/etiología , Caquexia/prevención & control , Glucanos , Obesidad/complicaciones , Ratas , Ratas Wistar
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 249: 119255, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33338938

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) became a useful analytical technique with the development of appropriate metallic substrates. The need for SERS substrates that immobilize metallic nanoparticles prompted this work to search for an appropriate material. This work presents the preparation, characterization and application of a SERS substrate for crystal violet (CV) detection, as the probe molecule. The inner layer of the substrate is a thin film of the fungal ß-D-glucan, botryosphaeran, covered by a thin layer of silver nanoparticles (AgNPs). The nanoparticles were produced by laser ablation, a fast and clean method for their preparation, and the layers were assembled by casting. Scanning electron and atomic force microscopies, UV-VIS and Raman spectroscopy and X-ray diffraction allowed the characterization of the surface of the substrate. Analysis by Raman spectroscopy showed promising results for SERS amplification on the substrate. Detection of CV reached enhancement factors up to 106 orders of magnitude, compared to normal Raman spectra. Linearity was observed for analyses on the SERS substrate at concentration ranges of 0.005 to 1 µmol L-1. The assembly reached the detection of 12 pmol cm-2 of CV, which corresponds to 96 fg of the probe molecule contained in the area of the substrate effectively interacting with the laser. The substrate was more efficient than silver colloids to perform SERS.


Asunto(s)
Nanopartículas del Metal , Espectrometría Raman , Violeta de Genciana , Polisacáridos , Plata
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