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1.
Int J Nanomedicine ; 17: 5469-5488, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36426372

RESUMEN

Introduction: Titanium (Ti) and its alloys (eg, Ti6Al4V) are exceptional treatments for replacing or repairing bones and damaged surrounding tissues. Although Ti-based implants exhibit excellent osteoconductive performance under healthy conditions, the effectiveness and successful clinical achievements are negatively altered in diabetic patients. Concernedly, diabetes mellitus (DM) contributes to osteoblastic dysfunctionality, altering efficient osseointegration. This work investigates the beneficial osteogenic activity conducted by nanostructured TiO2 under detrimental microenvironment conditions, simulated by human diabetic serum. Methods: We evaluated the bone-forming functional properties of osteoblasts on synthesized TiO2 nanotubes (NTs) by anodization and Ti6Al4V non-modified alloy surfaces under detrimental diabetic conditions. To simulate the detrimental environment, MC3T3E-1 preosteoblasts were cultured under human diabetic serum (DS) of two diagnosed and metabolically controlled patients. Normal human serum (HS) was used to mimic health conditions and fetal bovine serum (FBS) as the control culture environment. We characterized the matrix mineralization under the detrimental conditions on the control alloy and the NTs. Moreover, we applied immunofluorescence of osteoblasts differentiation markers on the NTs to understand the bone-expression stimulated by the biochemical medium conditions. Results: The diabetic conditions depressed the initial osteoblast growth ability, as evidenced by altered early cell adhesion and reduced proliferation. Nonetheless, after three days, the diabetic damage was suppressed by the NTs, enhancing the osteoblast activity. Therefore, the osteogenic markers of bone formation and the differentiation of osteoblasts were reactivated by the nanoconfigured surfaces. Far more importantly, collagen secretion and bone-matrix mineralization were stimulated and conducted to levels similar to those of the control of FBS conditions, in comparison to the control alloy, which was not able to reach similar levels of bone functionality than the NTs. Conclusion: Our study brings knowledge for the potential application of nanostructured biomaterials to work as an integrative platform under the detrimental metabolic status present in diabetic conditions.


Asunto(s)
Diabetes Mellitus , Nanotubos , Humanos , Células Cultivadas , Nanotubos/química , Osteoblastos , Aleaciones , Diabetes Mellitus/metabolismo
2.
Vet Res Forum ; 13(2): 169-176, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35919852

RESUMEN

Piglets suffer from diarrhea caused by the Shiga toxin-producing Escherichia coli (STEC) and can be carriers of the bacteria, with public health consequences in developing countries. The aim of the present study was to study the prevalence of STEC O157 in feces of 465 piglets and 54 food mixes from backyard systems, the antimicrobial susceptibility of STEC and the frequency of genes encoding extended-spectrum ß-lactamases. The E. coli was isolated from 75.90 % of the evaluated feces. The STEC strains were identified in 33.11% of the sampled population and in 43.60% of the piglets carrying E. coli. Among STEC strains, the stx1 gene was the most frequent (22.30%). The rfbO157 gene was amplified in 47.40% of the STEC strains. High frequencies of STEC strains were not susceptible to ampicillin, carbenicillin and tetracycline. The blaTEM gene (52) was the most frequent among strains not susceptible to ampicillin. Class 1 integrons were the most frequent in those strains. Of the identified STEC strains, 48.70% were considered as multi-drug resistant and 1.90% were considered extensively drug resistant. In the supplied food, STEC O157 strains were identified in 25.00% of the STEC strains. We conclude that the piglets from backyard systems are carriers of STEC O157 strains not susceptible to common antibiotics, including penicillins and tetracyclines. In addition, supplied food is a source of this type of pathogenic bacteria. Through their direct contact with humans, the piglets and food represent a potential source of bacterial dissemination capable of producing gastrointestinal infections in humans.

3.
Biology (Basel) ; 12(1)2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36671765

RESUMEN

Rhizobacteria from desert plants can alleviate biotic stress and suppress plant diseases, and consequently can enhance plant growth. Therefore, the current study was performed to isolate and identify Prosopis glandulosa-associating rhizobacteria based on their antagonistic activity against Fusarium species and plant growth-promoting properties. Three bacterial isolates were identified as Bacillus subtilis: LDA-1, LDA-2, and LDA-3. The molecular analysis suggests the biosynthesis of the bacteriocins subtilisin and subtilosin, as well as the lipopeptide iturin, by these strains. In addition, the antagonistic study by dual-culture assay showed a high efficacy of all B. subtilis strains against phytopathogenic fungi (Fusarium nygamai, F. equisseti, F. solani, F. solani ICADL1, and F. oxysporum ICADL2) with inhibition percentages ranging from 43.3 to 83.5% in comparison to the control. Moreover, atomic force microscopy (AFM) analysis showed significant differences in the cell wall topography of the F. solani ICADL1 among the treated mycelia and untreated control. As a result, these three B. subtilis strains were used as bioinoculants for cotton seedlings infected by F. solani ICADL1 in pot trials, and the results revealed that the bacterial inoculations as an individual or combined with F. solani ICADL1 significantly improved cotton root and stem length, lateral roots, indole acetic acid (IAA), and gibberellic acid (GA3) contents, as well as increased antioxidants, flavonoids, and phenols in comparison to those obtained from healthy and infected control plants. In conclusion, the three bacterial strains of B. subtilis (i.e., LDA-1, LDA-2, and LDA-3) are considered promising tools as biocontrol agents for F. solani and cotton growth promoters, and consequently can be used as bio-ertilizer in sustainable agriculture systems.

4.
ScientificWorldJournal ; 2021: 5561930, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34220365

RESUMEN

The use of phytonanoparticles in agriculture could decrease the use of fertilizers and therefore decrease soil contamination, due to their size being better assimilated in plants. It is important to mention that the nanofertilizer is slow-releasing and improves plant physiological properties and various nutritional parameters. The influence of soil and foliar applications of phytonanoparticles of ZnO with the Moringa oleifera extract under three concentrations (25, 50, and 100 ppm) was evaluated on the cherry tomato crop (Solanum lycopersicum L.). Synthesis of the phytonanoparticles was analyzed with ultraviolet-visible spectroscopy (UV-Vis) and infrared transmission spectroscopy with Fourier transform (FT-IR), as well as the analysis with the dynamic light scattering (DLS) technique. The morphometric parameters were evaluated before and after the application of the nanoparticles. The minerals' content of fruits was done 95 days after planting. Results showed that soil application was better at a concentration of 25 ppm of phytonanoparticles since it allowed the greatest number of flowers and fruits on the plant; however, it was demonstrated that when performing a foliar application, the fruit showed the highest concentrations for the elements Mg, Ca, and Na at concentrations of 511, 4589, and 223 mg kg-1, respectively.


Asunto(s)
Nanopartículas/análisis , Suelo/química , Solanum lycopersicum/química , Óxido de Zinc/análisis , Agricultura
5.
Mater Sci Eng C Mater Biol Appl ; 119: 111501, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33321601

RESUMEN

Current outbreaks associated with drug-resistant clinical strains are demanding for the development of broad-spectrum antibacterial agents. The bactericidal materials should be eco-friendly, economical and effective to suppress bacterial growth. Thus, in this work, diameter controlled spherical Cucore-Agshell nanoparticles (Ag@CuNPs) with diameter ranging from 70 to 100 nm by one-step co-reduction approach were designed and synthesized. The Ag@CuNPs were homogenous, stable, and positively charged. The 70 nm Ag@CuNPs showed a consistent and regular Ag shielding. We observed the 100 nm Ag@CuNPs achieved symmetrical doped Ag clusters on the Cu core surface. We used Gram-positive and Gram-negative models strains to test the wide-spectrum antibacterial activity. The Ag@CuNPs showed detrimental microbial viability in a dose-dependent manner; however, 70 nm Ag@CuNPs were superior to those of 100 nm Ag@CuNPs. Initially, Ag@CuNPs attached and translocated the membrane surface resulting in bacterial eradication. Our analyses exhibited that antibacterial mechanism was not governed by the bacterial genre, nonetheless, by cell type, morphology, growing ability and the NPs uptake capability. The Ag@CuNPs were highly tolerated by human fibroblasts, mainly by the use of starch as glucosidic capper and stabilizer, suggesting optimal biocompatibility and activity. The Ag@CuNPs open up a novel platform to study the potential action of bimetallic nanoparticles and their molecular role for biomedical, clinical, hospital and industrial-chemical applications.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Plata/farmacología , Relación Estructura-Actividad
6.
Int J Phytoremediation ; 23(7): 747-754, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33284665

RESUMEN

Different types of nanoparticles (NPs) are increasingly used in multiple sectors such as industry, medicine and agriculture. This application has increased the possibility of NPs accumulating and contaminating the environment. Plants are one of the essential building blocks of all ecosystems and the interaction between NPs and plants is an indispensable aspect of risk assessment. To understand the effects of NPs in agricultural systems, in the present study we investigated the effects of exposure of Ag, Cu and Cu/Ag phytonanoparticles in Arachis hypogaea L. plants at a physiological and biochemical level, for which NPs solutions were applied foliarly at concentrations of 250, 500, 750 and 1000 ppm for 48 days. Parameters such as leaf length, chlorophyll and concentration of phytohormones showed that phytonanoparticles could cause serious damage to plant growth and development. Plants exposed to phytonanoparticles showed an increase in total phenols, proline, PAL activity and antioxidant enzymes, this to mitigate the stress caused. The alteration in the composition and content of fatty acids in the peanut kernels after exposure to different NPs indicated that they could affect the yield and quality of crop. Therefore, it is necessary to investigate its potential impact on food quality. Statement of noveltyIn this manuscript, we report for the first time that green nanoparticles induced a lower degree of toxicity in plants compared to commercial nanoparticles.Our results indicate that the mechanisms by which peanut plants respond to the application of nanoparticles were an increase in the activity of phenylalanine ammonia-lyase and antioxidant enzymes. So far there are few studies on the effect of nanoparticles on plant hormones, our results revealed a significant decrease in indole-3 acetic acid and induced the synthesis of gibberellins. The modification in the composition and content of fatty acids in the peanut kernels indicated that the nanoparticles could affect the quality of the crop.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Arachis , Biodegradación Ambiental , Ecosistema , Hojas de la Planta
7.
Endocrinol. diabetes nutr. (Ed. impr.) ; 67(4): 235-244, abr. 2020. tab, graf
Artículo en Español | IBECS | ID: ibc-194799

RESUMEN

INTRODUCCIÓN: En México, en los últimos años, se ha incrementado la prevalencia de sobrepeso y obesidad, condición que favorece el desarrollo de enfermedades crónico-degenerativas. Implementar estrategias para incrementar en la población el consumo diario de vegetales, leguminosas, cereales de grano entero y frutas implicará una ingesta adecuada de fibra soluble, antioxidantes, proteínas de origen vegetal y vitaminas. OBJETIVO: Evaluar el efecto de un producto alimenticio comercial elaborado a base de 6 leguminosas sobre determinados parámetros antropométricos y bioquímicos en sujetos sanos. MÉTODOS: Ensayo aleatorizado de intervención dietética, en el que los sujetos del grupo de estudio recibieron durante 3 meses 15 g del producto, administrados diariamente en periodos de 5 días con 2 días de descanso. Antes y después de la intervención se realizó una valoración antropométrica y dietética, así como una cuantificación sérica de glucosa, perfil de lípidos, insulina, proteína C reactiva ultrasensible, malondialdehído y resistencia a la insulina (índice HOMA). Se utilizó la prueba U de Mann Whitney y una significación estadística de p < 0,05. RESULTADOS: Se incluyeron 60 estudiantes universitarios (53% hombres). Al término de la intervención, en el grupo de estudio se obtuvo una disminución en los niveles séricos de glucosa (p = 0,001), malondialdehído (p = 0,001) e índice HOMA (p = 0,017), sin cambios significativos en el resto de los parámetros. CONCLUSIONES: La ingesta diaria de 15 g de un producto a base de leguminosas mejoró en el grupo estudiado los niveles séricos de glucosa y malondialdehído, así como la resistencia a la insulina, lo cual podría atribuirse al contenido de polifenoles e isoflavonas como la genisteína, presente en las leguminosas


INTRODUCTION: Prevalence of overweight and obesity, a condition that promotes development of chronic degenerative diseases, has increased in Mexico in recent years. Implementation of strategies to increase daily consumption of vegetables, legumes, whole grain cereals, and fruits by the population will result in an adequate intake of soluble fiber, antioxidants, protein of vegetable origin, and vitamins. OBJECTIVE: To assess the effect of a commercial food product prepared using 6 legumes on some anthropometric and biochemical parameters in apparently healthy subjects. METHODS: A randomized dietary intervention trial where subjects in the study group received for three months 15g of the product, administered daily in periods of five days with two days of rest. Before and after intervention, anthropometric and dietary assessments were performed, and serum glucose, lipid profile, insulin, ultrasensitive C-reactive protein, malondialdehyde (MDA) and insulin resistance (HOMA index) were measured. A Mann-Whitney U test was used and values of P < 0.05 were considered statistically significant. RESULTS: Sixty university students were included in the study (53% males). At the end of the intervention, decreases were seen in serum glucose levels (P = 0.001), MDA (P = 0.001) and HOMA index (P = 0.017), but there were no significant changes in all other parameters. CONCLUSIONS: Daily intake of 15g of the legume-based food product improved serum glucose and malondialdehyde levels in the study group, as well as insulin resistance; which could be attributed to the presence of polyphenols and isoflavones such as genistein in legumes


Asunto(s)
Adulto , Fabaceae , Malondialdehído/sangre , Lípidos/sangre , Resistencia a la Insulina , Glucosa/análisis , Antropometría , Alimentos Formulados , Jugos de Frutas y Vegetales , Dietética , Biomarcadores/sangre
8.
Endocrinol Diabetes Nutr (Engl Ed) ; 67(4): 235-244, 2020 Apr.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31759909

RESUMEN

INTRODUCTION: Prevalence of overweight and obesity, a condition that promotes development of chronic degenerative diseases, has increased in Mexico in recent years. Implementation of strategies to increase daily consumption of vegetables, legumes, whole grain cereals, and fruits by the population will result in an adequate intake of soluble fiber, antioxidants, protein of vegetable origin, and vitamins. OBJECTIVE: To assess the effect of a commercial food product prepared using 6 legumes on some anthropometric and biochemical parameters in apparently healthy subjects. METHODS: A randomized dietary intervention trial where subjects in the study group received for three months 15g of the product, administered daily in periods of five days with two days of rest. Before and after intervention, anthropometric and dietary assessments were performed, and serum glucose, lipid profile, insulin, ultrasensitive C-reactive protein, malondialdehyde (MDA) and insulin resistance (HOMA index) were measured. A Mann-Whitney U test was used and values of P<0.05 were considered statistically significant. RESULTS: Sixty university students were included in the study (53% males). At the end of the intervention, decreases were seen in serum glucose levels (P=0.001), MDA (P=0.001) and HOMA index (P=0.017), but there were no significant changes in all other parameters. CONCLUSIONS: Daily intake of 15g of the legume-based food product improved serum glucose and malondialdehyde levels in the study group, as well as insulin resistance; which could be attributed to the presence of polyphenols and isoflavones such as genistein in legumes.


Asunto(s)
Glucemia/análisis , Colesterol/sangre , Dieta , Fabaceae , Alimentos Especializados , Resistencia a la Insulina , Malondialdehído/sangre , Triglicéridos/sangre , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven
9.
Rev. argent. microbiol ; 51(2): 103-109, jun. 2019. ilus, graf, tab
Artículo en Inglés | LILACS | ID: biblio-1013358

RESUMEN

In the present work, the biosynthesis of silver-nanoparticles (AgNP) was evaluated using the aqueous extract from Justicia spicigera. The obtained silver nanoparticles were characterized using UV-visible spectroscopic techniques, energy dispersive X-ray spectrometers (EDS), zeta potential and dynamic light scattering. The antimicrobial activity of biosynthesized AgNP was tested against foodborne bacteria (Bacillus cereus, Klebsiella pneumoniae and Enterobacter aerogenes) and phytopathogenic fungi (Colletotrichum sp., Fusarium solani, Alternaria alternata and Macrophomina phaseolina). The elemental profile of synthesized nanoparticles using J. spicigera shows higher counts at 3 keV due to silver, confirming the formation of silver nanoparticles. Scanning electron microscopy (SEM) analysis showed a particle size between 86 and 100 nm with spherical morphology. AgNP showed effective antibacterial and antifungal activity against the tested organisms principally with B. cereus, K. pneumoniae, E. aerogenes, A. alternata and M. phaseolina. Therefore, further studies are needed to confirm the potential of AgNP from J. spicigera in the control of indicator organisms under field conditions.


En el presente trabajo se evaluó la biosíntesis de nanopartículas de plata (AgNP) en presencia de una sal de plata y extractos acuosos de Justicia spicigera. Las nanopartículas así obtenidas fueron caracterizadas mediante técnicas espectroscópicas UV-visibles, espectrómetros de rayos X de energía dispersiva (EDS), potencial zeta y dispersión de luz dinámica. La actividad antimicrobiana de las AgNP biosintetizadas se probó frente a diversas bacterias transmitidas por alimentos (Bacillus cereus, Klebsiella pneumoniae y Enterobacter aerogenes) y hongos fitopatógenos (Colletotrichum sp., Fusarium solani, Alternaria alternata y Macrophomina phaseolina). El perfil elemental de las nanopartículas sintetizadas utilizando el extracto de J. spicigera mostró valores altos a 3 keV, lo que confirma la formación de nanopartículas de plata. El análisis por microscopía electrónica de barrido (SEM) reveló un tamaño de partícula entre 86 y 100 nm, con morfología esférica. Las AgNP mostraron una actividad antibacteriana y antifúngica efectiva contra los organismos evaluados, principalmente contra B. cereus, K. pneumoniae, E. aerogenes, A. alternata y M. phaseolina. Se necesitan más estudios para confirmar el potencial de las AgNP derivadas de J. spicigera en el control de organismos indicadores en condiciones de campo.


Asunto(s)
Plata/uso terapéutico , Control Biológico de Vectores , Nanopartículas del Metal/análisis , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Antiinfecciosos , Antifúngicos
10.
Rev Argent Microbiol ; 51(2): 103-109, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30029815

RESUMEN

In the present work, the biosynthesis of silver-nanoparticles (AgNP) was evaluated using the aqueous extract from Justicia spicigera. The obtained silver nanoparticles were characterized using UV-visible spectroscopic techniques, energy dispersive X-ray spectrometers (EDS), zeta potential and dynamic light scattering. The antimicrobial activity of biosynthesized AgNP was tested against foodborne bacteria (Bacillus cereus, Klebsiella pneumoniae and Enterobacter aerogenes) and phytopathogenic fungi (Colletotrichum sp., Fusarium solani, Alternaria alternata and Macrophomina phaseolina). The elemental profile of synthesized nanoparticles using J. spicigera shows higher counts at 3keV due to silver, confirming the formation of silver nanoparticles. Scanning electron microscopy (SEM) analysis showed a particle size between 86 and 100nm with spherical morphology. AgNP showed effective antibacterial and antifungal activity against the tested organisms principally with B. cereus, K. pneumoniae, E. aerogenes, A. alternata and M. phaseolina. Therefore, further studies are needed to confirm the potential of AgNP from J. spicigera in the control of indicator organisms under field conditions.


Asunto(s)
Bacterias , Agentes de Control Biológico , Microbiología de Alimentos , Hongos , Género Justicia/metabolismo , Nanopartículas del Metal , Plata/metabolismo , Enfermedades de las Plantas/microbiología
11.
Open Life Sci ; 14: 62-68, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33817138

RESUMEN

The present study was conducted to evaluate the impact of monometallic and bimetallic nanoparticles (NPs) of copper (Cu) and silver (Ag) from Justicia spicigera on the photochemical efficiency and phenol pattern of Prosopis glandulosa. In this study, the existence of localized surface plasmon resonance absorption associated with the nano-sized nature of Ag, Cu and Cu/Ag particles was confirmed by the presence of a single peak around 487, 585, and 487/580 nm respectively. Zeta potential and electrophoretic mobility were found to be 0.2 mV and 0.02 µmcm/(Vs) for synthesized NPs indicating less stability and thus tendency to agglomerate, and broad distribution of particles. Cu-NPs and Cu/Ag-NPs demonstrate that the dispersed phase is stable and has a minimum particle size at zeta potentials above -30 mV. Changes in phenolic compounds, total chlorophyll, and photochemical efficiency in leaves exposed to Ag, Cu and Cu/Ag phyto-nanoparticles were evaluated up to 72 hours. The results revealed that Ag-NP and Cu-NP from J. spicigera at 100 mg/L showed significant reduction in chlorophyll, epidermal polyphenol content and photochemical efficiency of P. glandulosa. In contrast, the application of bimetallic Cu/Ag-NP from J. spicigera showed a positive impact on physiological parameters of P. glandulosa after 72 h of exposure.

12.
Mycobiology ; 46(1): 47-51, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29998032

RESUMEN

In the present study, the characterization and properties of silver nanoparticles from Yucca shilerifera leaf extract (AgNPs) were investigated using UV-visible spectroscopic techniques, zeta potential, and dynamic light scattering. The UV-visible spectroscopic analysis showed the absorbance peaked at 460 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 729 nm with lower stability (195.1 mV). Additionally, our dates revealed that AgNPs showed broad spectrum antagonism (p ≤ .05) against Fusarium solani (83.05%) and Macrophomina phaseolina (67.05%) when compared to the control after nine days of incubation. Finally, AgNPs from leaf extracts of Y. shilerifera may be used as an agent of biocontrol of microorganism of importance. However, further studies will be needed to fully understand the agronanotechnological potentialities of AgNPs from Yucca schidigera.

13.
An Acad Bras Cienc ; 90(2): 1465-1472, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29898105

RESUMEN

The aim of the present work is to evaluate the changes on the phenylalanine ammonia lyase (PAL) activity, phenolic compounds accumulation and photochemical efficiency in leaves of P. glandulosa treated with Cd2+ (0.001 M) and Cu2+ (0.52 M) concentrations for 96 h under hydroponic conditions. The results showed that only leaves treated with copper had a decrease in photochemical efficiency and leaf epidermal polyphenols in P. glandulosa leaves after 96 h of exposure. On the other hand the reverse-phase HPLC analysis revealed higher levels of phenolic compound (gallic, vanillic and caffeic acids) and flavonoids (rutin and kaempferol-3-O-glucosides) in plant leaves from Cu and Cd-treatments with respect to control plants. Finally, highest increments in PAL activity was observed in extracts of leaves treated with Cu and Cd (about 205 and 284%), respectively, with respect to control plants after 96 h treatment. These suggest that activation of phenylpropanoid pathway represent a source of nonenzymatic antioxidants that protect at P. glandulosa against oxidative stress when exposed to cadmium and copper. Hence future studies are necessary to elucidate the participation of phenylpropanoid pathway in the reduction of metal toxicity in Prosopis species.


Asunto(s)
Cadmio/farmacología , Cobre/farmacología , Flavonoides/metabolismo , Fenoles/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Hojas de la Planta/efectos de los fármacos , Prosopis/efectos de los fármacos , Cromatografía Líquida de Alta Presión , México , Fenilanina Amoníaco-Liasa/efectos de los fármacos , Hojas de la Planta/metabolismo , Prosopis/química
14.
Mycobiology ; 45(4): 385-391, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29371807

RESUMEN

The ability of Bacillus subtilis, strain ALICA to produce three mycolytic enzymes (chitinase, ß-1,3-glucanase, and protease), was carried out by the chemical standard methods. Bacillus subtilis ALICA was screened based on their antifungal activity in dual plate assay and cell-free culture filtrate (25%) against five different phytopathogenic fungi Alternaria alternata, Macrophomina sp., Colletotrichum gloeosporioides, Botrytis cinerea, and Sclerotium rolfesii. The B. subtilis ALICA detected positive for chitinase, ß-1,3-glucanase and protease enzymes. Fungal growth inhibition by both strain ALICA and its cell-free culture filtrate ranged from 51.36% to 86.3% and 38.43% to 68.6%, respectively. Moreover, hyphal morphological changes like damage, broken, swelling, distortions abnormal morphology were observed. Genes expression of protease, ß-1,3-glucanase, and lipopeptides (subtilosin and subtilisin) were confirmed their presence in the supernatant of strain ALICA. Our findings indicated that strain ALICA provided a broad spectrum of antifungal activities against various phytopathogenic fungi and may be a potential effective alternative to chemical fungicides.

15.
J Oleo Sci ; 65(4): 311-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26972464

RESUMEN

The aim of this study was analyze the effect of jasmonic acid (JA) and abscisic acid (ABA) as elicitors on fatty acids profile (FAP), phenolic compounds (PC) and antioxidant capacity (AC) in callus of Thevetia peruviana. Schenk & Hildebrandt (SH) medium, supplemented with 2 mg/L 2, 4-dichlorophenoxyacetic (2, 4-D) and 0.5 mg/L kinetin (KIN) was used for callus induction. The effect of JA (50, 75 and 100 µM) and ABA (10, 55 and 100 µM) on FAP, PC and AC were analyzed using a response surface design. A maximum of 2.8 mg/g of TPC was obtained with 100 plus 10 µM JA and ABA, respectively, whereas AC maximum (2.17 µg/mL) was obtained with 75 plus 100 µM JA and ABA, respectively. The FAP was affected for JA but not for ABA. JA increased cis-9, cis-12-octadecadienoic acid and decreased dodecanoic acid. Eight fatty acids were identified by GC-MS analysis and cis-9-octadecenoic acid (18:1) was the principal fatty acid reaching 76 % in treatment with 50 µM JA plus 55 µM ABA. In conclusion, JA may be used in T. peruviana callus culture for obtain oil with different fatty acids profile.


Asunto(s)
Ácido Abscísico/farmacología , Antioxidantes/análisis , Ciclopentanos/farmacología , Ácidos Grasos/análisis , Oxilipinas/farmacología , Fenoles/análisis , Thevetia/química , Acetatos , Ácidos Grasos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Cinetina , Ácidos Láuricos/análisis , Ácidos Esteáricos/análisis
16.
Rev. argent. microbiol ; 47(1): 72-77, mar. 2015. graf
Artículo en Español | BINACIS | ID: bin-133902

RESUMEN

En el presente estudio se evaluó el efecto de extractos fenólicos y de carotenoides procedentes de frutos de chiltepín sobre el crecimiento micelial y la germinación de conidios de Alternaria alternata y Fusarium oxysporum, 2 importantes hongos causantes de podredumbres en frutas y hortalizas. Los extractos fenólicos presentaron una inhibición en el crecimiento micelial de A. alternata del 38,46 %, y redujeron significativamente la germinación de conidios al quinto día después del tratamiento al 92 % en relación al control. No se observaron cambios significativos en el crecimiento micelial de F. oxysporum, pero sí se redujo significativamente al 85 % en relación al control, el número de conidios germinados a los 5 días de tratamiento. Los extractos de carotenoides mostraron una inhibición del 38,5 % en el crecimiento micelial y del 85,3 % en la germinación de conidios de A. alternata, 5 días después del tratamiento. Frente a F. oxysporum, dichos extractos presentaron menor inhibición del crecimiento micelial (20,3 %), mientras que hubo una mayor inhibición en la germinación de conidios (96 %). Los extractos fenólicos y de carotenoides de chiltepín pueden ser una alternativa promisoria de importancia agrícola como fungicidas naturales.(AU)


The effect of phenolic and carotenoid extracts from chiltepin fruits on mycelial growth and the inhibition of conidial germination of Alternaria alternata and Fusarium oxysporum were investigated in the present work. Phenolic extracts inhibited mycelial growth of A. alternata by 38.46%, and significantly reduced conidial germination on the fifth day after treatment to 92% in relation to control. No significant changes were observed in the inhibition of mycelial growth in Fusarium oxysporum; however, the number of germinated conidia was reduced, showing 85% inhibition five days after treatment in relation to control. Moreover, carotenoid extracts showed 38.5% inhibition of mycelial growth and 85.3% inhibition of conidial germination of A. alternata, five days after treatment. Carotenoid extracts showed less inhibition of mycelial growth (20.3%) in F. oxysporum, with respect to A. alternata; while there was greater inhibition of conidial germination (96%) on the fifth day after treatment. Phenolic and carotenoid extracts from chiltepin may be a promising alternative as a natural fungicide against fungi of agricultural importance.(AU)

17.
Rev. argent. microbiol ; 47(1): 72-77, Mar. 2015. graf
Artículo en Español | LILACS | ID: lil-757143

RESUMEN

En el presente estudio se evaluó el efecto de extractos fenólicos y de carotenoides procedentes de frutos de chiltepín sobre el crecimiento micelial y la germinación de conidios de Alternaria alternata y Fusarium oxysporum, 2 importantes hongos causantes de podredumbres en frutas y hortalizas. Los extractos fenólicos presentaron una inhibición en el crecimiento micelial de A. alternata del 38,46 %, y redujeron significativamente la germinación de conidios al quinto día después del tratamiento al 92 % en relación al control. No se observaron cambios significativos en el crecimiento micelial de F. oxysporum, pero sí se redujo significativamente al 85 % en relación al control, el número de conidios germinados a los 5 días de tratamiento. Los extractos de carotenoides mostraron una inhibición del 38,5 % en el crecimiento micelial y del 85,3 % en la germinación de conidios de A. alternata, 5 días después del tratamiento. Frente a F. oxysporum, dichos extractos presentaron menor inhibición del crecimiento micelial (20,3 %), mientras que hubo una mayor inhibición en la germinación de conidios (96 %). Los extractos fenólicos y de carotenoides de chiltepín pueden ser una alternativa promisoria de importancia agrícola como fungicidas naturales.


The effect of phenolic and carotenoid extracts from chiltepin fruits on mycelial growth and the inhibition of conidial germination of Alternaria alternata and Fusarium oxysporum were investigated in the present work. Phenolic extracts inhibited mycelial growth of A. alternata by 38.46%, and significantly reduced conidial germination on the fifth day after treatment to 92% in relation to control. No significant changes were observed in the inhibition of mycelial growth in Fusarium oxysporum; however, the number of germinated conidia was reduced, showing 85% inhibition five days after treatment in relation to control. Moreover, carotenoid extracts showed 38.5% inhibition of mycelial growth and 85.3% inhibition of conidial germination of A. alternata, five days after treatment. Carotenoid extracts showed less inhibition of mycelial growth (20.3%) in F. oxysporum, with respect to A. alternata; while there was greater inhibition of conidial germination (96%) on the fifth day after treatment. Phenolic and carotenoid extracts from chiltepin may be a promising alternative as a natural fungicide against fungi of agricultural importance.


Asunto(s)
Alternaria/efectos de los fármacos , Capsicum , Fusarium/efectos de los fármacos , Extractos Vegetales/farmacología , Carotenoides , Fenoles , Esporas Fúngicas/efectos de los fármacos
18.
Rev Argent Microbiol ; 47(1): 72-7, 2015.
Artículo en Español | MEDLINE | ID: mdl-25705046

RESUMEN

The effect of phenolic and carotenoid extracts from chiltepin fruits on mycelial growth and the inhibition of conidial germination of Alternaria alternata and Fusarium oxysporum were investigated in the present work. Phenolic extracts inhibited mycelial growth of A.alternata by 38.46%, and significantly reduced conidial germination on the fifth day after treatment to 92% in relation to control. No significant changes were observed in the inhibition of mycelial growth in Fusarium oxysporum; however, the number of germinated conidia was reduced, showing 85% inhibition five days after treatment in relation to control. Moreover, carotenoid extracts showed 38.5% inhibition of mycelial growth and 85.3% inhibition of conidial germination of A.alternata, five days after treatment. Carotenoid extracts showed less inhibition of mycelial growth (20.3%) in F.oxysporum, with respect to A.alternata; while there was greater inhibition of conidial germination (96%) on the fifth day after treatment. Phenolic and carotenoid extracts from chiltepin may be a promising alternative as a natural fungicide against fungi of agricultural importance.


Asunto(s)
Alternaria/efectos de los fármacos , Capsicum , Fusarium/efectos de los fármacos , Extractos Vegetales/farmacología , Carotenoides , Fenoles , Esporas Fúngicas/efectos de los fármacos
19.
Rev. Argent. Microbiol. ; 47(1): 72-7, 2015 Jan-Mar.
Artículo en Español | BINACIS | ID: bin-133758

RESUMEN

The effect of phenolic and carotenoid extracts from chiltepin fruits on mycelial growth and the inhibition of conidial germination of Alternaria alternata and Fusarium oxysporum were investigated in the present work. Phenolic extracts inhibited mycelial growth of A.alternata by 38.46


, and significantly reduced conidial germination on the fifth day after treatment to 92


in relation to control. No significant changes were observed in the inhibition of mycelial growth in Fusarium oxysporum; however, the number of germinated conidia was reduced, showing 85


inhibition five days after treatment in relation to control. Moreover, carotenoid extracts showed 38.5


inhibition of mycelial growth and 85.3


inhibition of conidial germination of A.alternata, five days after treatment. Carotenoid extracts showed less inhibition of mycelial growth (20.3


) in F.oxysporum, with respect to A.alternata; while there was greater inhibition of conidial germination (96


) on the fifth day after treatment. Phenolic and carotenoid extracts from chiltepin may be a promising alternative as a natural fungicide against fungi of agricultural importance.

20.
An Acad Bras Cienc ; 85(2): 665-70, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23828363

RESUMEN

The effects of copper toxicity on the photosynthetic activities of Avicennia germinans was investigated using two CuSO4 concentrations (0.062 and 0.33 M) added in Hoagland's solution in an aerated hydroponic system. Photosynthesis and chlorophyll fluorescence were measured after 30 h of copper stress. Results obtained in this study show that increasing levels of Cu(+2) of 0.062 and 0.33 M Cu(+2) resulted in a general reduction of the stomatal conductance (28 and 18%, respectively) and 100% of inhibition of net photosynthesis. Additionally, at these concentrations of Cu(+2), reductions of chlorophyll fluorescence parameters were also observed. These changes suggested that the photosynthetic apparatus of Avicennia germinans was the primary target of the Cu(+2) action. It is concluded that Cu(+2) ions causes a drastic decline in photosynthetic gas exchange and Chlorophyll fluorescence parameters in A. germinans leaves.


Asunto(s)
Avicennia/efectos de los fármacos , Clorofila/metabolismo , Cobre/toxicidad , Fotosíntesis/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Fluorescencia
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