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1.
Microorganisms ; 12(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38930506

RESUMO

Biotic stress in cotton plants caused by the phytopathogenic fungus Colletotrichum gossypii var. cephalosporioides triggers symptoms of ramulosis, a disease characterized by necrotic spots on young leaves, followed by death of the affected branch's apical meristem, plant growth paralysis, and stimulation of lateral bud production. Severe cases of ramulosis can cause up to 85% yield losses in cotton plantations. Currently, this disease is controlled exclusively by using fungicides. However, few studies have focused on biological alternatives for mitigating the effects of contamination by C. gossypii var. cephalosporioides on cotton plants. Thus, the hypothesis raised is that endophytic fungi isolated from an Arecaceae species (Butia purpurascens), endemic to the Cerrado biome, have the potential to reduce physiological damage caused by ramulosis, decreasing its severity in these plants. This hypothesis was tested using plants grown from seeds contaminated with the pathogen and inoculated with strains of Gibberella moniliformis (BP10EF), Hamigera insecticola (BP33EF), Codinaeopsis sp. (BP328EF), G. moniliformis (BP335EF), and Aspergillus sp. (BP340EF). C. gossypii var. cephalosporioides is a leaf pathogen; thus, the evaluations were focused on leaf parameters: gas exchange, chlorophyll a fluorescence, and oxidative metabolism. The hypothesis that inoculation with endophytic strains can mitigate physiological and photochemical damage caused by ramulosis in cotton was confirmed, as the fungi improved plant growth and stomatal index and density, increased net photosynthetic rate (A) and carboxylation efficiency (A/Ci), and decreased photochemical stress (ABS/RC and DI0/RC) and oxidative stress by reducing enzyme activity (CAT, SOD, and APX) and the synthesis of malondialdehyde (MDA). Control plants developed leaves with a low adaxial stomatal index and density to reduce colonization of leaf tissues by C. gossypii var. cephalosporioides due to the absence of fungal antagonism. The Codinaeopsis sp. strain BP328EF can efficiently inhibit C. gossypii var. cephalosporioides in vitro (81.11% relative inhibition), improve gas exchange parameters, reduce photochemical stress of chlorophyll-a, and decrease lipid peroxidation in attacked leaves. Thus, BP328EF should be further evaluated for its potential effect as a biological alternative for enhancing the resistance of G. hirsutum plants and minimizing yield losses caused by C. gossypii var. cephalosporioides.

2.
Macromol Rapid Commun ; : e2400302, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877645

RESUMO

Polyamide 6 fiber has the advantages of high strength and good wear resistance. However, it is still challenging to effectively load inorganic antibacterial agents into polymer substrates without antimicrobial activity. In this work, graphene oxide was used as a carrier, which was modified with an aminosilane coupling agent (AEAPTMS) to enhance the compatibility and antimicrobial properties of the inorganic material, as well as to improve its thermal stability in a high-temperature melting environment. Cuprous oxide-loaded aminated grapheme (Cu2O-GO-NH2) was constructed by in situ growth method, and further PA6/Cu2O-GO-NH2 fibers were prepared by in situ polymerization. The composite fiber has excellent washing resistance. After 50 times washing, its bactericidal rates against Bacillus subtilis and Escherichia coli were 98.85% and 99.99%, respectively. In addition, the enhanced compatibility of Cu2O-GO-NH2 with the PA6 matrix improved the orientation and crystallinity of the composite fibers. Compared with PA6/Cu2O-GO fibers, the fracture strength of PA6/Cu2O-GO-NH2 fibers increased from 3.0 cN/dtex to 4.2 cN/dtex when the addition of Cu2O-GO-NH2 was 0.2 wt.%. Chemical modification and in situ concepts help to improve the compatibility of inorganic antimicrobial agents with organic polymers, which can be applied to the development of medical textiles. This article is protected by copyright. All rights reserved.

3.
Macromol Biosci ; : e2300528, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444237

RESUMO

Hydrogel wound dressing can accelerate angiogenesis to achieve rapid wound healing, but traditional hydrogel dressings are difficult to meet the repair of joint sites due to their low mechanical strength. Therefore, we constructed the gel system by designing the chemical-physical interpenetrating network structure to achieve high strength and high toughness of the hydrogel. The high-strength double-network hydrogels were synthesized by simple free radical polymerization and low-temperature physicochemical cross-linking in our experiments. The suspension was obtained by green reduction of graphene oxide with carboxymethyl chitosan, followed by the introduction of acrylamide (AM) to form a covalent cross-linked network, which was immersed in ferric chloride solution to form metal ligand bonds, and finally the chemical-physical dual cross-linked network hydrogel wound dressing was prepared. Here, reduced graphene oxide can enhance electrical conductivity and excellent near-infrared photothermal effect to the hydrogel. The cell viability of this novel wound dressing was above 90.0%, its hemolysis rate was below 2.0%, and the electrical conductivity could reach (6.89 ± 0.07 (mS/cm)). In addition, the stress-strain curve demonstrated that the double cross-linked network hydrogel could reach a stress of more than 0.8 MPa at 82.0% strain, and the cyclic compression experiment shows that it can still recover its original shape after five times of repeated compression. This work can provide a reference for the exploitation of high mechanical strength hydrogel wound dressings with good electrical conductivity and near-infrared photothermal effect. This article is protected by copyright. All rights reserved.

4.
ACS Appl Mater Interfaces ; 16(11): 13573-13584, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38439708

RESUMO

Periodontitis, a complex inflammatory disease initiated by bacterial infections, presents a significant challenge in public health. The increased levels of reactive oxygen species and the subsequent exaggerated immune response associated with periodontitis often lead to alveolar bone resorption and tooth loss. Herein, we develop multifunctional metal-phenolic composites (i.e., Au@MPN-BMP2) to address the complex nature of periodontitis, where gold nanoparticles (AuNPs) are coated by metal-phenolic networks (MPNs) and bone morphogenetic protein 2 (BMP2). In this design, MPNs exhibit remarkable antibacterial and antioxidant properties, and AuNPs and BMP2 promote osteogenic differentiation of bone marrow mesenchymal stem cells under inflammatory conditions. In a rat model of periodontitis, treatment with Au@MPN-BMP2 leads to notable therapeutic outcomes, including mitigated oxidative stress, reduced progression of inflammation, and the significant prevention of inflammatory bone loss. These results highlight the multifunctionality of Au@MPN-BMP2 nanoparticles as a promising therapeutic approach for periodontitis, addressing both microbial causative factors and an overactivated immune response. We envision that the rational design of metal-phenolic composites will provide versatile nanoplatforms for tissue regeneration and potential clinical applications.


Assuntos
Nanopartículas Metálicas , Periodontite , Ratos , Animais , Osteogênese , Ouro/farmacologia , Nanopartículas Metálicas/uso terapêutico , Periodontite/tratamento farmacológico , Antibacterianos/farmacologia , Diferenciação Celular
5.
Front Microbiol ; 15: 1304682, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516010

RESUMO

Lettuce is an economically major leafy vegetable that is affected by numerous diseases. One of the most devastating diseases of lettuce is white mold caused by Sclerotinia sclerotiorum. Control methods for this fungus are limited due to the development of genetic resistance to commonly used fungicides, the large number of hosts and the long-term survival of sclerotia in soil. To elaborate a new and more sustainable approach to contain this pathogen, 1,210 Pseudomonas strains previously isolated from agricultural soils in Canada were screened for their antagonistic activity against S. sclerotiorum. Nine Pseudomonas strains showed strong in vitro inhibition in dual-culture confrontational assays. Whole genome sequencing of these strains revealed their affiliation with four phylogenomic subgroups within the Pseudomonas fluorescens group, namely Pseudomonas corrugata, Pseudomonas asplenii, Pseudomonas mandelii, and Pseudomonas protegens. The antagonistic strains harbor several genes and gene clusters involved in the production of secondary metabolites, including mycin-type and peptin-type lipopeptides, and antibiotics such as brabantamide, which may be involved in the inhibitory activity observed against S. sclerotiorum. Three strains also demonstrated significant in planta biocontrol abilities against the pathogen when either inoculated on lettuce leaves or in the growing substrate of lettuce plants grown in pots. They however did not impact S. sclerotiorum populations in the rhizosphere, suggesting that they protect lettuce plants by altering the fitness and the virulence of the pathogen rather than by directly impeding its growth. These results mark a step forward in the development of biocontrol products against S. sclerotiorum.

6.
Front Microbiol ; 15: 1336515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529179

RESUMO

Crop production often faces challenges from plant diseases, and biological control emerges as an effective, environmentally friendly, cost-effective, and sustainable alternative to chemical control. Wheat blast disease caused by fungal pathogen Magnaporthe oryzae Triticum (MoT), is a potential catastrophic threat to global food security. This study aimed to identify potential bacterial isolates from rice and wheat seeds with inhibitory effects against MoT. In dual culture and seedling assays, three bacterial isolates (BTS-3, BTS-4, and BTLK6A) demonstrated effective suppression of MoT growth and reduced wheat blast severity when artificially inoculated at the seedling stage. Genome phylogeny identified these isolates as Bacillus subtilis (BTS-3) and B. velezensis (BTS-4 and BTLK6A). Whole-genome analysis revealed the presence of genes responsible for controlling MoT through antimicrobial defense, antioxidant defense, cell wall degradation, and induced systemic resistance (ISR). Taken together, our results suggest that the suppression of wheat blast disease by seed endophytic B. subtilis (BTS-3) and B. velezensis (BTS-4 and BTLK6A) is liked with antibiosis and induced systemic resistance to wheat plants. A further field validation is needed before recommending these endophytic bacteria for biological control of wheat blast.

7.
Exp Appl Acarol ; 92(2): 203-215, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38321310

RESUMO

The red palm mite Raoiella indica Hirst, 1924 (Acari: Tenuipalpidae) is an important pest of the coconut palm Cocos nucifera L. (Arecaceae) and has caused problems in coconut production worldwide. Research has been carried out aiming at controlling the mite through chemical, biological, alternative, and host plant resistance methods. Identifying coconut palm cultivars resistant to R. indica is important to reduce the problems caused to plantations. Therefore, the objective of this work was to evaluate the performance of R. indica in six dwarf coconut palm cultivars, to identify sources of resistance. The cultivars of the sub-varieties green, red, and yellow evaluated were Brazilian Green Dwarf-Jiqui (BGDJ), Brazilian Red Dwarf-Gramame (BRDG), Cameroon Red Dwarf (CRD), Malayan Red Dwarf (MRD), Brazilian Yellow Dwarf-Gramame (BYDG), and Malayan Yellow Dwarf (MYD). Confinement and free choice tests of R. indica on the cultivars were performed, in which biological parameters and preference were evaluated. Mite performance was different in the cultivars evaluated. In the confinement bioassay, R. indica had the worst performance in the cultivar BGDJ, the best performance in CRD, MRD, and BRDG, and intermediate performance in BYDG and MYD. In the free choice test, the cultivars MRD and MYD were preferred in relation to BGDJ, and CRD was less preferred in relation to BGDJ. Therefore, we considered that the cultivar BGDJ is the most resistant to R. indica, by antibiosis and antixenosis; CRD has resistance by antixenosis; and MRD, BRDG, BYDG, and MYD are susceptible.


Assuntos
Arecaceae , Ácaros , Trombiculidae , Animais , Cocos , Brasil
8.
J Fungi (Basel) ; 10(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38248975

RESUMO

Flower blight caused by Neopestalotiopsis clavispora is an emerging disease of flamingo flower (Anthurium andraeanum Lind.) that negatively impacts flower production. The use of rhizosphere fungi as biocontrol agents is an alternative way to control this disease instead of using synthetic fungicides. This research aimed to screen the potential of rhizosphere fungi, Trichoderma spp., with diverse antifungal abilities to control N. clavispora and to reduce flower blight in flamingo flowers. A total of ten isolates were tested against N. clavispora by dual culture assay, and T1-02 was found to be the most effective isolate against N. clavispora, with inhibition of 78.21%. Morphology and molecular phylogeny of multiple DNA sequences of the genes, the internal transcribed spacer (ITS), translation elongation factor 1-α (tef1-α), and RNA polymerase 2 (rpb2) identified isolate T1-02 as Trichoderma virens. Sealed plate method revealed T. virens T1-02 produced volatile antifungal compounds (VOCs) against N. clavispora, with inhibition of 51.28%. Solid-phase microextraction (SPME) was applied to trap volatiles, and GC/MS profiling showed VOCs emitted from T. virens T1-02 contained a sesquiterpene antifungal compound-germacrene D. The pre-colonized plate method showed that T. virens T1-02 aggressively colonized in tested plates with inhibition of 100% against N. clavispora, and microscopy revealed direct parasitism onto fungal hyphae. Furthermore, the application of T. virens T1-02 spore suspension reduced the disease severity index (DSI) of flower blight in flamingo flowers. Based on the results from this study, T. virens T1-02 displays multiple antagonistic mechanisms and has the potential ability to control flower blight of flamingo flowers caused by N. clavispora.

9.
Chem Biodivers ; 21(2): e202301308, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163260

RESUMO

Flavonoids, known for their abundance in Eucommia ulmoides pollen, possess diverse biological functions, including antioxidants, antibacterial agents, and anti-tumor properties. This study aims to establish effective parameters for flavonoid extraction from Eucommia ulmoides pollen using a microwave-assisted method, characterize the flavonoid composition of the extracted material, and explore its biological activities. Building upon the initial results from single-factor experiments, response surface methodology was employed to optimize the extraction parameters. The inhibitory effect of human breast cancer cells (MCF-7) was evaluated by CCK assay and Live/dead staining. Simultaneously, the extract's scavenging ability against DPPH free radicals and its antibacterial properties against Escherichia coli and Staphylococcus aureus were investigated. The results demonstrated that the flavonoid yield reached 3.28 g per 100 g of pollen, closely aligning with the predicted value. The IC50 for flavonoid-mediated DPPH radical scavenging was 0.04 mg/mL. The extract exhibited a robust inhibitory effect on both Escherichia coli and Staphylococcus aureus. Concurrently, the extract displayed a significant inhibitory effect on the growth and proliferation of MCF-7 cells in a dose-dependent and time-dependent manner. In addition, six kinds of flavonoids have been identified by UPLC-TOF-MS/MS technology, providing further support to the study on the anti-oxidation and anti-tumor mechanism of Eucommia ulmoides pollen extracts.


Assuntos
Eucommiaceae , Humanos , Eucommiaceae/química , Flavonoides/farmacologia , Espectrometria de Massas em Tandem , Antioxidantes/farmacologia , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Escherichia coli
10.
Int J Biol Macromol ; 254(Pt 2): 127862, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939775

RESUMO

Functionalization of bio-based nanofibers is the development tendency of high-performance air filter. However, the conventional structural optimization strategy based on high solution conductivity greatly hinders the development of fully bio-based air filter, and not conducive to sustainable development. This work fabricated fully bio-based nanofibrous membrane with formaldehyde-adsorbable and antibacterial capabilities by electrospinning low-conductivity solution for high-performance air filtration and applied to lightweight mask. The "water-like" ethyl cellulose (EC) was selected as the base polymer to "nourish" functional materials of gelatin (GE), ß-cyclodextrin (ßCD), and curcumin (Cur), thus forming a solution system with high binding energy differences and electrospinning into ultrafine bimodal nanofibers. The filtration efficiency for 0.3 µm NaCl particles, pressure drop, and quality factor were 99.25 %, 53 Pa, and 0.092 Pa-1, respectively; the bacteriostatic rates against Escherichia coli and Staphylococcus aureus were 99.9 % and 99.4 %, respectively; the formaldehyde adsorption capacity was 442 µg/g. This is the first report on antibacterial and formaldehyde-adsorbable high-performance air filter entirely made from bio-based materials. This simple strategy will greatly broaden the selection of materials for preparing high-performance multifunctional air filter, and promote the development of bio-based air filter.


Assuntos
Curcumina , Nanofibras , Nanofibras/química , Curcumina/farmacologia , Gelatina , Filtração , Antibacterianos/farmacologia
11.
Adv Mater ; 36(13): e2311519, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127976

RESUMO

Effective personal protection is crucial for controlling infectious disease spread. However, commonly used personal protective materials such as disposable masks lack antibacterial/antiviral function and may lead to cross infection. Herein, a polyethylene glycol-assisted solvent-free strategy is proposed to rapidly synthesize a series of the donor-acceptor metal-covalent organic frameworks (MCOFs) (i.e., GZHMU-2, JNM-1, and JNM-2) under air atmosphere and henceforth extend it via in situ hot-pressing process to prepare MCOFs based films with photocatalytic disinfect ability. Best of them, the newly designed GZHMU-2 has a wide absorption spectrum (200 to 1500 nm) and can efficiently produce reactive oxygen species under sunlight irradiation, achieving excellent photocatalytic disinfection performance. After in situ hot-pressing as a film material, the obtained GZHMU-2/NMF can effectively kill E. coli (99.99%), S. aureus (99%), and H1N1 (92.5%), meanwhile possessing good reusability. Noteworthy, the long-term use of a GZHMU-2/NWF-based mask has verified no damage to the living body by measuring the expression of mouse blood routine, lung tissue, and inflammatory factors at the in-vivo level.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Estruturas Metalorgânicas , Animais , Camundongos , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia
12.
Insects ; 14(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38132579

RESUMO

The common bean (Phaseolus vulgaris L.) is an important leguminous crop providing low-cost protein in developing countries worldwide. Insect pests are the main threats to common bean production, and this article focuses on the soybean looper (SL) Chrysodeixis includens (Walker, 1858) (Lepidoptera: Noctuidae), which feeds on leaves and pods. The recurrent use of synthetic chemicals may lead to pest resistance. Genetically resistant plants may diminish their use. Thus, the objective was to study common bean genotypes' resistance toward SL. The plants were grown in greenhouse conditions. The biology, fertility life table, oviposition preference and free-choice feeding preference were analyzed. Phenol and flavonoid content were assessed in leaves using a biology assay. Uirapuru genotype negatively affected C. includens biology and reproduction. Tangará genotype favored these parameters. Genotypes Quero-Quero, Nhambu, Corujinha, Andorinha, ANFC 9, Siriri, BRS Radiante and Verdão were more attractive for third-instar larvae. Negative correlations between phenolic and flavonoid compounds with survival rate (from egg to adult) rate were found. Common bean genotypes with dark leaves are less preferred for oviposition.

13.
Nat Prod Res ; : 1-7, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37971976

RESUMO

To determine how vulnerable various pea genotypes are to leafminer infestation, a field experiment was conducted. On the basis of the presence of mines on five randomly selected leaflets from the upper, middle and lower parts of the plant, observations of larvae were made throughout the growing season. The total phenols were determined using the method described by Bray and Thorpe (1954, Analysis of phenolic compounds of interest in metabolism. Methods Biochem Anal. 52:1-27) and absorbance at 650 nm was measured using a spectrophotometer. There was a negative correlation between leafminer infestation and total phenol content. The UHF Pea-12 genotype, characterised by the lowest total phenol concentration (20.87 mg/100 g), exhibited the highest level of leaflet infestation (17.33%). Although UHF Pea-1 genotype had the lowest mean leaflet infestation (6.58%), it also had the highest phenol concentration (41.91 mg per 100 g). In context with this, the present study highlights the significance of host-plant resistance (HPR) in pest management.

14.
Heliyon ; 9(11): e21653, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954375

RESUMO

Root-knot nematodes (Meloidogyne spp.) are obligate sedentary endoparasites, considered severe crop-damaging taxa among all plant-parasitic nematodes globally. Their attacks through parasitic proteins alter the physiology and machinery of the host cells to favour parasitism and reduction in crop yield. Currently, the use of excessive pesticides as a fast remedy to manage this pest is hazardous for both the environment and humans. Keeping this view in mind, there is an urgent need for developing efficient eco-friendly strategies. Bio-control as an eco-friendly is considered the best approach to manage nematodes without disturbing non-target microbes. In bio-control, living agents such as fungi and bacteria are the natural enemies of nematodes and the best substitute for pesticides. Fungi, including nematode-trapping fungi, can sense host signals and produce special trapping devices viz., constricting rings and adhesive knobs/loops, to capture nematodes and kill them. Whereas, endo-parasitic fungi kill nematodes by enzymatic secretions and spore adhesion through their hyphae. Bacteria can also control nematodes by producing antibiotic compounds, competing for nutrients and rhizosphere, production of hydrolytic enzymes viz., chitinases, proteases, lipases, and induction of systemic resistance (ISR) in host plants. Scientists throughout the world are trying to evolve environmentally benign methods that sustain agricultural production and keep nematodes below a threshold level. Whatever methods evolve, in the future the focus should be on important aspects like green approaches for managing nematodes without disturbing human health and the environment.

15.
J Control Release ; 363: 657-669, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37832724

RESUMO

Peri-implantitis induced by infection leads to gingival recession, alveolar resorption and eventual dental implant failure. So, antibiosis and biosealing of abutments as well as osseointegration of roots need to be projected seriously during the whole service lifespan of dental implants. In this work, a multipurpose photothermal therapy strategy based on Si/P/F doped TiO2 matrix is proposed to address the above issues. This TiO2 matrix not only has outstanding photothermal response, but also triggers the release of F ions under near-infrared (NIR) light irradiation. Local hyperthermia assisted with the released F ions reduces adenosine triphosphate (ATP) synthesis of staphylococcus aureus (S. aureus), increases bacterial membrane permeability, and induces abundant of reactive oxygen species, resulting in the oxidation of cellular components and eventual death of bacteria. Furthermore, the synergic action of mild photothermal stimulation and Si/P/F ions of TiO2 matrix up-regulates gingival epithelial cells behavior (e.g., hemidesmosome formation) and osteoblasts response in vitro. In an infected model, this TiO2 matrix obviously eliminates bacteria, reduces inflammatory response, improves epithelial sealing and osseointegration, and reduces alveolar resorption by regulating NIR irradiation.


Assuntos
Perda do Osso Alveolar , Humanos , Fluoretos , Staphylococcus aureus , Antibiose , Regeneração Óssea , Titânio , Antibacterianos/farmacologia
16.
Molecules ; 28(16)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37630187

RESUMO

Numerous plants of medicinal value grow on Hainan Island (China). Given the lack of knowledge on the phytochemical and pharmacological properties of Michelia shiluensis Chun and Y. F. Wu (M. shiluensis), the application of natural antioxidants and antimicrobials in the food industry has attracted increasing interest. This study aimed to compare the chemical composition, free-radical-scavenging capacity, and antibiosis of aqueous extracts of the fresh and dried leaves of M. shiluensis. The aqueous extract of the leaves of M. shiluensis was obtained using steam distillation, and its chemical components were separated and identified via gas chromatography-mass spectrometry (GC-MS). The free-radical-scavenging capacity and antibiosis were determined. Further, 28 and 20 compounds were isolated from the fresh leaf aqueous extract of M. shiluensis (MSFLAE) and dried leaf aqueous extract of M. shiluensis (MSDLAE), respectively. The free-radical-scavenging capacity of MSFLAE and MSDLAE was determined by the 2,2-diphenyl-1 picrylhydrazyl (DPPH) method, which was 43.43% and 38.74%, respectively. The scavenging capacity of MSFLAE and MSDLAE determined by the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS)) method was 46.90% and 25.99%, respectively. The iron ion reduction capacity of MSFLAE and MSDLAE was determined by the ferric-reducing antioxidant power (FRAP) method as 94.7 and 62.9 µmol Fe2⁺/L, respectively. This indicated that the two leaf aqueous extracts had a certain free-radical-scavenging capacity, and the capacity of MSFLAE was higher than that of MSDLAE. The antibiosis of the two leaf aqueous extracts on the three foodborne pathogenic bacteria was low, but the antimicrobial effects on Gram-positive bacteria were better than those on Gram-negative bacteria. The antibiosis of MSFLAE on Escherichia coli and Staphylococcus aureus was greater than that of MSDLAE. Finally, MSFLAE and MSDLAE both had certain free-radical-scavenging capacities and antibiosis, confirming that the use of this plant in the research and development of natural antioxidants and antibacterial agents was reasonable. Plant aqueous extracts are an essential source of related phytochemistry and have immense pharmacological potential.


Assuntos
Antibiose , Magnoliaceae , Vapor , Alcanossulfonatos , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Escherichia coli
17.
Int J Biol Macromol ; 253(Pt 1): 126567, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37643671

RESUMO

Organic-inorganic composites as an efficient strategy to upgrade the structural and functional properties of synthetic polymers are attracting extensive attentions. However, there are few studies on the shape memory (SM) behavior of organic-inorganic composites. In the work, poly(ε-caprolactone) hybridized TiO2 nanomaterial (PCL-TiO2) is made as the switching phase and integrated into poly (l-lactide) (PLLA) to construct an SM composite. PCL-TiO2/PLLA shows "sea-island" structure and better interfacial adhesion than PCL/PLLA, which facilitates the transmission of elastic power between the switching phase and the fixing phase. PCL-TiO2 as switching phase exhibits lower enthalpy at 57 °C than PCL, and PCL-TiO2 also acts as "heat dispersion pump station", which builds a dynamically responsive system and initiates shape change. The shape fixing and recovery ratio of PCL-TiO2/PLLA are 93.9 % and 94.4 %, respectively, and go back to the original shape within 15 s at 57 °C. At the same time, PCL-TiO2 endows SMP with good antibacterial properties. Then this work provides a well-placed way for developing SM materials with structure-function integration.


Assuntos
Antibacterianos , Poliésteres , Poliésteres/química , Antibacterianos/química
18.
Front Plant Sci ; 14: 1167248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554561

RESUMO

Host Plant Resistance (HPR) is the most important component for sustainable management of insect pests. The purpose of the present work was to understand the role of various morphological and biochemical factors as defense mechanism and their interaction on different biological parameters attributed to survival and development of pink stem borer (PSB), Sesamia inferens Walker in maize. The resistant and moderately resistant genotypes (DMRE 63, CM 500 and WNZ Exotic pool) suffered least leaf injury rating (LIR), dead hearts (DH%), percentage stem tunneling (ST%), number of entry/exit holes (E/EH) and showed deleterious effects on biological parameters of pink stem borer as compared to susceptible ones (CM 202 and BML 6). Resistance index among the genotypes varied from 0.11 to 0.46. The variation in morphological traits such as number of nodes, internode distance and stem diameter could not distinguish all the resistant genotypes from that of susceptible genotypes in terms of its mean value. Higher levels of biochemical constituents, viz., p-Coumaric acid (p-CA), ferulic acid (FA), acid detergent fibre (ADF) and acid detergent lignin (ADL) were observed in resistant genotypes compared to susceptible ones. Antibiosis was expressed in terms of reduced pupal weight when fed on WNZ Exotic pool, whereas larval weight and larval survival affected when fed on DMRE 63. Higher concentration of p-CA content in pith of resistant maize genotypes prolonged the pupal period of pink stem borer. Higher concentration of p-CA and FA contents in rind reduced the adult emergence, as they showed significant negative correlation between them. The larval period was prolonged with higher levels of ADF and ADL contents in maize genotypes either in rind or both rind and pith as both ADF and ADL content showed a significant positive correlation with the larval period. The Pearson correlation analysis of most of the biochemical constituents revealed significant negative correlation with damage parameters. The correlation coefficients between p-CA with DH (%), ST (%) and E/EH were r= -0.9642**, r= -0.9363**, and r= -0.9646**, respectively. Similarly, the correlation coefficients between FA with DH (%), ST (%) and E/EH were r= -0.9217*, r= -0.9563**, and r= -0.9434**, respectively and ADF with DH (%), ST (%) and E/EH were r= -0.9506**, r= -0.9611**, and r= -0.9709**, respectively. The study confirms that stem damage parameters can also be used as selection criteria along with LIR to identify resistant genotypes against pink stem borer. Based on the correlation analysis it was concluded that resistance to pink stem borer in maize is the result of interaction of several morphological and biochemical traits rather than a single factor. The findings obtained from the present study can be utilised in pink stem borer resistance breeding programmes to enhance and diversify the basis of resistance.

19.
Front Nutr ; 10: 1193289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396128

RESUMO

"Medicine food homology" (MFH) is a term with a lengthy history. It refers to the fact that a lot of traditional natural products have both culinary and therapeutic benefits. The antibacterial, anti-inflammatory and anticancer effects of MFH plants and their secondary metabolites have been confirmed by numerous research. A bacterially generated inflammatory illness with a complicated pathophysiology, periodontitis causes the loss of the teeth's supporting tissues. Several MFH plants have recently been shown to have the ability to prevent and treat periodontitis, which is exhibited by blocking the disease's pathogens and the virulence factors that go along with them, lowering the host's inflammatory reactions and halting the loss of alveolar bone. To give a theoretical foundation for the creation of functional foods, oral care products and adjuvant therapies, this review has especially explored the potential medicinal benefit of MFH plants and their secondary metabolites in the prevention and treatment of periodontitis.

20.
J Econ Entomol ; 116(5): 1662-1670, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37441732

RESUMO

Leucoptera sinuella (Reutti) (Lepidoptera: Lyonetiidae) is a leaf miner specialist on Salicaceae recently introduced to Chile and Argentina, where it is causing economic damage to poplar plantations. We report a field survey in a poplar nursery naturally infested showing that regardless of the poplar hybrid taxon, high variability in resistance was observed among clones within families for oviposition and leaf-mining damage. A group of susceptible and resistant hybrid poplar clones was then selected for a laboratory evaluation of oviposition (antixenosis) and leaf-mining damage (antibiosis) on potted, rooted shoot cuttings. The concentration of condensed tannins (CTs) and salicinoid phenolic glucosides (SPGs) of the leaves of the selected clones from the laboratory study was also measured. Total oviposited eggs were positively correlated with leaf area, with the lowest oviposition on TMxT 11372 clone. The lowest percentage of mined leaf area was obtained for clones TMxT 11372, TMxT 11463, and TDxD 17574, but surprisingly no correlation between the percentage of mined leaf area and concentration of CTs and SPGs was found. Resistant poplar hybrids of our study could be suitable for breeding programs aimed for L. sinuella integrated pest management.

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