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1.
J Nat Prod ; 81(1): 78-84, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29303267

RESUMEN

Serpulanines A (1), B (2), and C (3) have been isolated from extracts of the rare Sri Lankan macrofungus Serpula sp. The structures of 1, 2, and 3 were elucidated by a combination of spectroscopic and single-crystal X-ray diffraction analyses. Serpulanines A (1) and B (2) both contain the rare (E)-2-hydroxyimino hydroxamic acid functional group array. A proposed biogenesis for serpulanine B (2) suggests that its (E)-2-hydroxyimino hydroxamic acid moiety arises from a diketopiperazine precursor. Synthetic serpulanine A (1) inhibited class I/II histone deacetylases in murine metastatic lung carcinoma cells with an IC50 of 7 µM.


Asunto(s)
Basidiomycota/química , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Tirosina/análogos & derivados , Tirosina/farmacología , Animales , Línea Celular Tumoral , Cristalografía por Rayos X/métodos , Células HeLa , Inhibidores de Histona Desacetilasas/aislamiento & purificación , Humanos , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Oxidación-Reducción , Tirosina/química , Tirosina/aislamiento & purificación
2.
BMC Complement Altern Med ; 15: 398, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26546450

RESUMEN

BACKGROUND: Macrofungi have an established history of use in traditional oriental medicine. Anthracophyllum lateritium is a terrestrial macrofungus found in the dry zone forest reserves in Sri Lanka. Yet there are no scientific reports on bioactive properties of this species. Hence, the current study was aimed at determining the antioxidant potential, in vitro antiproliferative activity and apoptotic effect induced by crude methanolic extract of A. lateritium against RD sarcoma cell line. METHOD: The crude extract of A. lateritium was dissolved in methanol (MEFCA) and antioxidant activity was evaluated using in vitro assays: inhibition of DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, ferric ion reducing power and 2-deoxy-D-ribose degradation assay. Total phenol and flavonoid contents of MEFCA were assayed using folin Ciocalteu method and aluminium chloride colorimetric method. In vitro cytotoxicity was determined using MTT assay against RD cells after 24 h exposure to MEFCA. Ethidium bromide/ acridine orange staining, DNA fragmentation and protein synthesis experiments were used to study the apoptotic features and antiproliferative activities of the treated cells. Glutathione assay and griess nitrite assay were used to analyze the reduced glutathione content and liberation of nitric oxide from apoptotic cells. RESULTS: MEFCA showed promising antioxidant activity with EC50 values of 8.00 ± 0.35 µg/mL for DPPH scavenging and 83.33 ± 0.45 µg/mL for 2-deoxy-D-ribose degradation assay. The phenolic content was 265.15 ± 0.46 of (w/w) % of Gallic acid equivalents and flavonoid content was 173.01 ± 0.35 of (w/w) % of Epigallocatechingallate. A. lateritium showed strong in vitro cytotoxic activity with an EC50 of 18.80 ± 4.83 µg/mL for MTT assay against RD cells. Ethidium bromide/acridine orange staining and DNA fragmentation indicated the apoptotic features of treated cells. Protein levels showed a dose dependent decrease supporting the fact that A. lateritium induces apoptosis of treated cells. Glutathione content and nitric oxide content of cells exhibited a dose dependent increase suggesting the apoptosis of RD cells was mediated by both nitrie ions and nitric oxide. CONCLUSIONS: The crude extract of the A. lateritium exhibited potent antioxidant, antiproliferative activity and apoptotic effect against RD cells providing supportive evidence for the ethnopharmacological use of this fungus in control of oxidative damage and remedy of cancer.


Asunto(s)
Agaricales/química , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Sarcoma/fisiopatología , Verduras/química , Antioxidantes/química , Proliferación Celular/efectos de los fármacos , Humanos , Fenoles/química , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sarcoma/tratamiento farmacológico , Sri Lanka
3.
RSC Adv ; 14(5): 3379-3389, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38259984

RESUMEN

The emergence of resistance in detrimental pathogenic bacteria towards well-recognized antibiotics has greatly impacted global medicine, consequently exploring potent antibacterial compounds is becoming a potential area of research. Although photocatalytic metal oxides have been extensively explored in this regard, their applicability is diminished due to the requirement of photon energy. Therefore, in our study, we explored the light-independent antibacterial effect of two unexplored titanium species, known as metatitanic acid (MTA) and potassium titanate, against Staphylococcus aureus, Escherichia coli, and Pseudomonas spp. using the disk diffusion method in Luria-Bertani agar medium, where the well-known antibiotic, gentamicin, was used as the positive control. These two titanium compounds were readily synthesized through a novel process which was originally developed for the extraction of TiO2 from ilmenite. The synthesized MTA was characterized using FT-IR, Raman spectroscopy, XRD, TGA, UV-visible spectroscopy, and SEM. According to our findings, both MTA and potassium titanate exhibited superior light-independent antibacterial properties, where for some concentrations, the effect was even greater than gentamicin. However, nano-TiO2 totally failed as an antibacterial compound against the tested three strains under dark conditions.

4.
Life (Basel) ; 11(5)2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-34069619

RESUMEN

Palms (Arecaceae) are substrates for a highly diverse range of fungi. Many species are known as saprobes and many are important plant pathogens. Over the course of our studies of micro-fungi from palms in Thailand, two new taxa were discovered. Morphological characteristics and phylogenetic analyses of combined ITS, LSU, SSU, and tef1-α sequence data revealed their taxonomic positions within Massarinaceae. There are currently ten genera identified and accepted in Massarinaceae, with the addition of the two new genera of Haplohelminthosporium and Helminthosporiella, that are introduced in this paper. Each new genus is provided with a full description and notes, and each new taxon is provided with an illustration for the holotype. A list of identified and accepted species of Helminthosporium with morphology, host information, locality, sequence data, and related references of Helminthosporium reported worldwide is provided based on records in Species Fungorum 2021. This work provides a micro-fungi database of Haplohelminthosporium, Helminthosporiella, and Helminthosporium which can be modified and validated as new data come to light.

5.
Microb Pathog ; 49(5): 211-6, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20558271

RESUMEN

Cholera caused by the O139 serogroup still remains a public health concern in certain regions of the world and the existing O1 vaccines do not cross-protect cholera caused by this serogroup. An aminolevulinic acid (ALA) auxotroph vaccine candidate against the O139 serogroup, designated as VCUSM2, was recently developed. It was found to be immunogenic in animal model studies but showed mild reactogenic effects due to the presence of two intact copies of Vibrio cholerae toxin (CTX) genetic element. In the present study we have modified the ctx operon by systematic allelic replacement methodology to produce a mutant strain, designated as VCUSM14. This strain has two copies of chromosomally integrated and mutated ctxA gene, encoding immunogenic but not toxic cholera toxin A subunit (CT-A). The amino acids arginine and glutamic acid at position 7th and 112th, respectively, in CT-A of VCUSM14 were substituted with lysine (R7K) and glutamine (E112Q), respectively. Two copies of the ace and zot genes present in the ctx operon were also deleted. Cholera toxin-ELISA using GM1 ganglioside showed that the both wild type CT and mutated CT were recognized by anti-CT polyclonal antibodies. VCUSM14 produced comparatively less amount of antigenic cholera toxin when compared to the VCUSM2 and Bengal wild type strain. VCUSM14 did not elicit fluid accumulation when inoculated into rabbit ileal loops at doses of 10(6) and 10(8) CFU. The colonization efficiency of VCUSM14 was one log lower than the parent strain, VCUSM2, which can be attributed to the ALA auxotrophy and less invasive properties of VCUSM14. VCUSM14, thus a non-reactogenic auxotrophic vaccine candidate against infection by O139 V. cholerae.


Asunto(s)
Ácido Aminolevulínico/metabolismo , Toxina del Cólera/genética , Vacunas contra el Cólera/genética , Vacunas contra el Cólera/inmunología , Vibrio cholerae O139/genética , Vibrio cholerae O139/inmunología , Sustitución de Aminoácidos/genética , Animales , Anticuerpos Antibacterianos/inmunología , Antitoxinas/inmunología , Toxina del Cólera/inmunología , Ensayo de Inmunoadsorción Enzimática , Íleon/patología , Ratones , Ratones Endogámicos BALB C , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/inmunología , Conejos , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vibrio cholerae O139/metabolismo , Vibrio cholerae O139/patogenicidad , Virulencia
6.
Cureus ; 12(11): e11521, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-33354465

RESUMEN

The differential diagnosis is broad when a patient presents with an altered mental status. Ethylene glycol poisoning, a life-threatening condition, can occur as an intentional self-harm attempt or unintentional consumption. It is metabolized in the liver by a series of enzymes, and the metabolites so formed are responsible for the majority of clinical effects. The diverse range of clinical effects includes central nervous system (CNS), gastrointestinal, cardiovascular system (CVS), pulmonary as well as renal effects. The evidence of metabolic acidosis, elevated anion gap, high osmolal gap, and calcium oxalate crystals in laboratory analysis strongly suggests ethylene glycol poisoning. The treatment traditionally consists of alcohol dehydrogenase inhibitors such as fomepizole or ethanol, and in some cases, hemodialysis is needed as well.

7.
Trop Biomed ; 36(2): 348-356, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33597395

RESUMEN

Diarrhoea is a leading killer of children, accounting for 9% of all deaths among children under age 5 worldwide and 3% in Malaysia in 2015. A large proportion of diarrhoea illnesses among children in developing countries are ascribed to an unknown etiology because microscopic examination was the only available technique which has low detection limits. The proposed study aimed to evaluate a new quadriplex PCR assay to detect parasitic pathogens namely E. histolytica, G. lamblia and C. parvum which considered responsible for the majority of human infections. Three set of specific primer pairs were designed for detection of parasitic pathogens. Quadriplex PCR assay was optimized and an internal amplification control was incorporated to check for PCR inhibitors in samples. The PCR assay was evaluated using spiked stool samples. Specific primer pairs were successfully designed and simultaneously amplified the targeted genes. The analytical sensitivity of the quadriplex PCR at the DNA level was found to be 50 ng DNA. The analytical specificity was evaluated with 11 reference protozoal and bacterial strains and was found to be 100%. We concluded that the developed quadriplex PCR assay was rapid and gave results within 5 hours which is essential for the identification of parasitic pathogen and might be useful as an additional diagnostic tool whenever time is important in the diagnosis of parasite that cause diarrhoea.

8.
Environ Technol ; 39(16): 2062-2072, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28662609

RESUMEN

Fats, oils and grease (FOG) congregate in grease traps and are a slowly biodegradable particulate organic matter, which may require enzymatic or hydrolytic conversion to form readily biodegradable soluble organic matter. The existing treatment methods employ water-based hydrolysis of FOG to form long-chain fatty acids (LCFAs). The LCFAs discharged into wastewater treatment system create functional difficulties, especially the inhibitory effect caused by accumulation of LCFAs. This study aims to find an effective treatment method for this persistent problem encountered in conventional wastewater treatment system. Solid-state degradation by lipolytic fungi was performed in a tray-type reactor as a novel approach of bioaugmentation. Grease trap waste samples were dried to have moisture content of 25-35% and mixed with coir fiber (1% w/v) for proper aeration. Each 10 mg/g dry weight of substrate was inoculated with 1 mL of spore suspension (1 × 107 spores/mL) of lipolytic fungi. Thereafter, moisture content in the reactor was increased to 65%, and incubated at 30°C. Within 72 h of post incubation, degradation efficiency of about 50% was recorded by fungal isolates. The feasibility of using developed protocol for FOG degradation was tested with a laboratory-scale prototype reactor.


Asunto(s)
Industria de Alimentos , Hongos , Aguas Residuales , Grasas , Industria de Procesamiento de Alimentos , Purificación del Agua
9.
J Agric Food Chem ; 55(4): 1212-20, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17249682

RESUMEN

Antioxidant efficacies of ethanol extracts of defatted raw hazelnut kernel and hazelnut byproducts (skin, hard shell, green leafy cover, and tree leaf) were evaluated by monitoring total antioxidant activity (TAA) and free-radical scavenging activity tests [hydrogen peroxide, superoxide radical, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical], together with antioxidant activity in a beta-carotene-linoleate model system, inhibition of oxidation of human low-density lipoprotein (LDL) cholesterol, and inhibition of strand breaking of supercoiled deoxyribonucleic acid (DNA). In addition, yield, content of phenolics, and phenolic acid profiles (free and esterified fractions) were also examined. Generally, extracts of hazelnut byproducts (skin, hard shell, green leafy cover, and tree leaf) exhibited stronger activities than hazelnut kernel at all concentrations tested. Hazelnut extracts examined showed different antioxidative efficacies, expected to be related to the presence of phenolic compounds. Among samples, extracts of hazelnut skin, in general, showed superior antioxidative efficacy and higher phenolic content as compared to other extracts. Five phenolic acids (gallic acid, caffeic acid, p-coumaric acid, ferulic acid, and sinapic acid) were tentatively identified and quantified (both free and esterified forms). Extracts contained different levels of phenolic acids. These results suggest that hazelnut byproducts could potentially be considered as an excellent and readily available source of natural antioxidants.


Asunto(s)
Antioxidantes/análisis , Corylus/química , Nueces/química , Hojas de la Planta/química , Ácidos Carbocíclicos/análisis , Ácidos Carbocíclicos/farmacología , Antioxidantes/farmacología , LDL-Colesterol/química , Depuradores de Radicales Libres/farmacología , Humanos , Peroxidación de Lípido/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología
10.
J Agric Food Chem ; 54(4): 1256-64, 2006 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-16478245

RESUMEN

Two commercial samples of soft (70% Canadian Eastern soft red spring and 30% Canadian Eastern soft white winter) and hard (90% Canadian western hard red spring and 10% Canadian Eastern hard red winter) wheats were used to obtain different milling fractions. Phenolics extracted belonged to free, soluble esters and insoluble-bound fractions. Soluble esters of phenolics and insoluble-bound phenolics were extracted into diethyl ether after alkaline hydrolysis of samples. The content of phenolics was determined using Folin-Ciocalteu's reagent and expressed as ferulic acid equivalents (FAE). The antioxidant activity of phenolic fractions was evaluated using Trolox equivalent antioxidant capacity, 2,2-diphenyl-1-picrylhydrazyl radical scavenging, reducing power, oxygen radical absorbance capacity, inhibition of oxidation of human low-density lipoprotein cholesterol and DNA, Rancimat, inhibition of photochemilumenescence, and iron(II) chelation activity. The bound phenolic content in the bran fraction was 11.3 +/- 0.13 and 12.2 +/- 0.15 mg FAE/g defatted material for hard and soft wheats, respectively. The corresponding values for flour were 0.33 +/- 0.01 and 0.46 +/- 0.02 mg FAE/g defatted sample. The bound phenolic content of hard and soft whole wheats was 2.1 (+/-0.004 or +/-0.005) mg FAE/g defatted material. The free phenolic content ranged from 0.14 +/- 0.004 to 0.98 +/- 0.05 mg FAE/g defatted milling fractions of hard and soft wheats examined. The contribution of bound phenolics to the total phenolic content was significantly higher than that of free and esterified fractions. In wheat, phenolic compounds were concentrated mainly in the bran tissues. In the numerous in vitro antioxidant assays carried out, the bound phenolic fraction demonstrated a significantly higher antioxidant capacity than free and esterified phenolics. Thus, inclusion of bound phenolics in studies related to quantification and antioxidant activity evaluation of grains and cereals is essential.


Asunto(s)
Antioxidantes/análisis , Fenoles/análisis , Fenoles/metabolismo , Triticum/química , Compuestos de Bifenilo , Esterificación , Harina/análisis , Depuradores de Radicales Libres , Peroxidación de Lípido/efectos de los fármacos , Fenoles/química , Picratos , Semillas/química , Solubilidad
11.
J Agric Food Chem ; 53(7): 2433-40, 2005 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-15796575

RESUMEN

Phenolic compounds from soft and hard wheat and their milling fractions were extracted into distilled deionized water, and their in vitro antioxidant activities were evaluated. Wheat samples were used as such (nontreated) or subjected to pH adjustment (treated) in order to simulate gastrointestinal pH conditions. The total phenolic content (TPC) was determined using Folin-Ciocalteu's procedure. The total antioxidant activity (TAA) was determined using Trolox equivalent antioxidant capacity assay and expressed as Trolox equivalents. The antioxidant activity of wheat extracts was also evaluated using the beta-carotene bleaching assay, scavenging of 2,2-diphenyl-1-picrylhydrazyl radical, and inhibition of oxidation of human low density lipoprotein cholesterol. The TPC, TAA, and antioxidant potential, evaluated using different methods of wheat samples, were significantly increased following gastrointestinal tract-simulated pH changes. Thus, digestion taking place in the gastrointestinal tract in vivo may also enhance the antioxidant properties of the extracts.


Asunto(s)
Antioxidantes/análisis , Ácido Gástrico/fisiología , Triticum/química , Antioxidantes/farmacología , Digestión , Ácido Edético/farmacología , Depuradores de Radicales Libres/análisis , Concentración de Iones de Hidrógeno , Hidrólisis , Quelantes del Hierro/química , Peroxidación de Lípido , Lipoproteínas LDL/química , Fenoles/análisis , Extractos Vegetales/farmacología , beta Caroteno/química
12.
J Invest Dermatol ; 123(2): 354-60, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15245436

RESUMEN

We have previously described a guinea-pig model where pigmented nevi similar to human nevi can be produced by application of low-dose topical 7,12-dimethylbenzanthracene (DMBA) followed by solar-simulated light. Five groups of guinea-pigs were used to test the effect of various spectral bands of solar-simulated light on low-dose DMBA-induced melanocytic nevi. Animals were irradiated with either UVB to near UVA2 (290-325 nm), UVA, visible light, full solar spectrum or no irradiation three times per wk for 12 mo to determine the broad-band effect of nevi-inducing irradiation. There was a significant increase in nevi/animal in the UVB-treated group (mean 1.53) compared with all groups (versus UVA 0.3, p<0.001; versus visible light 0.24, p<0.001; versus full spectrum (UVB+UVA+visible) 0.68, p=0.02; versus control (nil irradiation) 0.37, p=0.01). No differences in skin thickness were found between any group (p=0.11). In conclusion, we present a report of the active waveband of melanocytic nevi induction; where UVB to near UVA2 is the likely responsible waveband. Furthermore, because there was a significant decrease in nevi/animal receiving the full solar spectrum compared with the UVB group, it is possible that broad-band UVA and or visible light may be inhibitory wavebands for nevi induction.


Asunto(s)
Nevo Pigmentado/fisiopatología , Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversos , 9,10-Dimetil-1,2-benzantraceno , Animales , Carcinógenos , Modelos Animales de Enfermedad , Femenino , Cobayas , Luz , Nevo Pigmentado/inducido químicamente , Nevo Pigmentado/patología , Piel/patología
13.
J Agric Food Chem ; 51(13): 3790-6, 2003 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-12797745

RESUMEN

The quality of Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was determined by measuring proximate composition, minerals, vitamins, dietary fiber, amino acids, and taste active components (free amino acids, sugars, and organic acids). Fat was the predominant component in Tombul hazelnut (approximately 61%). The major minerals were potassium, phosphorus, calcium, magnesium, and selenium. Hazelnut was also found to serve as an excellent source of vitamin E (24 mg/100 g) and a good source of water soluble (B complex) vitamins and dietary fiber. The major amino acids were glutamic acid, arginine, and aspartic acid. The three nonessential amino acids and the essential amino acids contributed 44.9 and 30.9% to the total amino acids present, respectively, while lysine and tryptophan were the limiting amino acids in Tombul hazelnut. Twenty-one free amino acids, six sugars, and six organic acids were positively identified; among these, arginine, sucrose, and malic acid predominated, respectively. These taste active components may play a significant role in the taste and flavor characteristics of hazelnut. Thus, the present results suggest that Tombul hazelnut serves as a good source of vital nutrients and taste active components.


Asunto(s)
Corylus/química , Nueces/química , Aminoácidos/análisis , Ácidos Carboxílicos/análisis , Grasas de la Dieta/análisis , Fibras de la Dieta/análisis , Minerales/análisis , Gusto , Turquía , Vitaminas/análisis
14.
J Agric Food Chem ; 51(13): 3797-805, 2003 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-12797746

RESUMEN

The quality of crude hazelnut oil extracted from Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was determined by measuring lipid classes, fatty acids, and fat soluble bioactives (tocopherols and phytosterols). Oxygen uptake, peroxide value, thiobarbituric acid reactive substances, and alpha-tocopherol levels of stripped and crude hazelnut oils in bulk and oil-in-water (o/w) emulsion systems were also evaluated as indices of lipid oxidation over a 21 day storage period at 60 degrees C in the dark. The total lipid content of Tombul hazelnut was 61.2%, of which 98.8% were nonpolar and 1.2% polar constituents. Triacylglycerols were the major nonpolar lipid class and contributed nearly 100% to the total amount. Phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol were the most abundant polar lipids, respectively. Sixteen fatty acids were identified, among which oleic acid contributed 82.7% to the total, followed by linoleic, palmitic, and stearic acids. Unsaturated fatty acids accounted for 92.2% of the total fatty acids present. Among oil soluble bioactives, alpha-tocopherol (38.2 mg/100 g) and beta-sitosterol (105.5 mg/100 g) were predominant in hazelnut oil and comprised 88 and 93% of the total tocopherols and phytosterols present, respectively. The results also showed that both stripped and crude hazelnut oils were more stable in terms of lipid oxidation in the bulk oil as compared to those in an o/w emulsion.


Asunto(s)
Corylus/química , Lípidos/análisis , Nueces/química , Aceites de Plantas/química , Estabilidad de Medicamentos , Ácidos Grasos/análisis , Oxidación-Reducción , Fitosteroles/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Tocoferoles/análisis , alfa-Tocoferol/análisis
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