RESUMO
The agriculture is extremely important for the life of human beings. Therefore, it is needed to control the enemies that destroy vast areas of crops causing great economic losses. Chemical pesticides were the option for many decades, but the damage that they cause to environment and human health led to the idea of changing the use of these for more sustainable options such as biopesticides as a biological control. Among microbial pesticides, Serratia species have been found as suitable options to apply against several pests or pathogens. Serratia species produce a wide range of secondary metabolites with several biological activities such as antifungal, antibacterial, and pesticides which can be used in sustainable agriculture. It has been reported that several Serratia species are able to suppress some crop diseases caused by Fusarium oxysporum, Rhizoctonia solani, Phytophthora parasitica, Sclerotinia sclerotiorum, Verticillium dahlia, and Phytophthora capsici among others. Therefore, they have been used as biocontrol agents in agriculture. In this review, we summarized the genus Serratia describing its history and development and the metabolites it secretes, which are responsible for their antibacterial and antifungal activity. We have analyzed the insecticide capacity of several Serratia species as well antifungal properties of Serratia species against most important crops' pathogens. In conclusion, the use of Serratia as a biological control agent against plant pathogens can be a good option for a sustainable agriculture. More work is needed to assess the safety of the isolated new strains and their effectiveness against pathogens in in vivo conditions.
Assuntos
Inseticidas , Praguicidas , Humanos , Antifúngicos/metabolismo , Serratia , Antibacterianos , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologiaRESUMO
Several fungi act as parasites for crops causing huge annual crop losses at both pre- and post-harvest stages. For years, chemical fungicides were the solution; however, their wide use has caused environmental contamination and human health problems. For this reason, the use of biofungicides has been in practice as a green solution against fungal phytopathogens. In the context of a more sustainable agriculture, microbial biofungicides have the largest share among the commercial biocontrol products that are available in the market. Precisely, the genus Bacillus has been largely studied for the management of plant pathogenic fungi because they offer a chemically diverse arsenal of antifungal secondary metabolites, which have spawned a heightened industrial engrossment of it as a biopesticide. In this sense, it is indispensable to know the wide arsenal that Bacillus genus has to apply these products for sustainable agriculture. Having this idea in our minds, in this review, secondary metabolites from Bacillus having antifungal activity are chemically and structurally described giving details of their action against several phytopathogens. Knowing the current status of Bacillus secreted antifungals is the base for the goal to apply these in agriculture and it is addressed in depth in the second part of this review.
Assuntos
Antifúngicos , Bacillus , Microbiologia Industrial , Controle Biológico de Vetores , Doenças das Plantas , Humanos , Agricultura/métodos , Agricultura/tendências , Antifúngicos/metabolismo , Bacillus/genética , Bacillus/metabolismo , Fungicidas Industriais/metabolismo , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Produtos Agrícolas/microbiologia , Controle Biológico de Vetores/métodos , Controle Biológico de Vetores/tendências , Família Multigênica/genéticaRESUMO
Phenylpropanoids belong to a wide group of compounds commonly secreted by plants and involved in different roles related with plant growth and development and the defense against plant pathogens. Some key intermediates from shikimate pathway are used to synthesize these compounds. In this way, by the phenylpropanoid pathway several building blocks are achieved to obtain flavonoids, isoflavonoids, coumarins, monolignols, phenylpropenes, phenolic acids, stilbenes and stilbenoids, and lignin, suberin and sporopollenin for plant-microbe interactions, structural support and mechanical strength, organ pigmentation, UV protection and acting against pathogens. Some reviews have revised phenylpropanoid biosynthesis and regulation of the biosynthetic pathways. In this review, the most important chemical structures about phenylpropanoid derivatives are summarized grouping them in different sections according to their structure. We have put special attention on their different roles in plants especially in plant health, growth and development and plant-environment interactions. Their interaction with microorganisms is discussed including their role as antimicrobials. We summarize all new findings about new developed structures and their involvement in plants health.
Assuntos
Flavonoides , Plantas , Flavonoides/metabolismo , Lignina/metabolismoRESUMO
The antibiotic-resistant bacteria are emerging as a great threat worldwide. For this reason it is important to develop new antibiotic substances. Bacillus is considered as a factory of a wide range of chemical compounds with a variety of activities. Among these substances are bacteriocins which are small peptides showing stability in a wide range of pH and temperatures and having a potent antibacterial activity. Bacillus species can be grouped into families such as B. cereus group based on their genetic similarity. It can be helpful to study the bacteriocins presented in these related species identifying the differences and similarities between them to relate the presence of a given bacteriocin with the producer specie. The aim of this study was to isolate the bacteriocins from three related species of B. cereus group such as B. mycoides, B. weihenstephanensis and B. toyonensis and compare among them and with the bacteriocins isolated from B. velezensis. Besides it was analyzed the bactericidal activity of each isolated bacteriocin. Five different bacteriocins of similar molecular mass and specific against foodborne pathogens were isolated from three Bacillus species related to B. cereus group, that were quite different both in molecular mass and bactericidal activity from that was isolated from B. velezensis. The results indicated that bacteriocins can be distinguished according to Bacillus specie from it has been isolated.
Assuntos
Bacillus , Bacteriocinas , Cactaceae , Humanos , Bacteriocinas/farmacologia , Antibacterianos/farmacologia , Peso MolecularRESUMO
Soil microbes promote plant growth through several mechanisms such as secretion of chemical compounds including plant growth hormones. Among the phytohormones, auxins, ethylene, cytokinins, abscisic acid and gibberellins are the best understood compounds. Gibberellins were first isolated in 1935 from the fungus Gibberella fujikuroi and are synthesized by several soil microbes. The effect of gibberellins on plant growth and development has been studied, as has the biosynthesis pathways, enzymes, genes and their regulation. This review revisits the history of gibberellin research highlighting microbial gibberellins and their effects on plant health with an emphasis on the early discoveries and current advances that can find vital applications in agricultural practices.
Assuntos
Giberelinas , Reguladores de Crescimento de Plantas , Agricultura , Produtos Agrícolas/metabolismo , Citocininas/metabolismo , Giberelinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismoRESUMO
During the past years, microorganisms have been the cause of many problems for human's health. However, today with the development of many techniques of microbiology, the researchers have studied several roles of microorganisms which may help the society. Microbial-based products are expected to play important role in agriculture-enhancing plant production and therefore increasing crop's yieldeswani et al. . Microorganisms can act by several action mechanisms including antibiosis or mechanisms in plant-microbe interactions underlining the dual function of microbial strains toward plant nutrition and protection. The market has increased with the development of microbial-based products. Currently, it is normal to think that microorganisms help us in agriculture by applying them as biological control. In this mini review, we collect the last findings about this topic including very recent literature. KEY POINTS: ⢠Microorganisms play a beneficial role in agriculture by different mechanisms. ⢠One of these mechanisms is the secretion of chemical compounds with different activities.
Assuntos
Agricultura , Microbiologia do Solo , Antibiose , Humanos , PlantasRESUMO
The whole organisms can be packaged as biopesticides, but secondary metabolites secreted by microorganisms can also have a wide range of biological activities that either protect the plant against pests and pathogens or act as plant growth promotors which can be beneficial for the agricultural crops. In this review, we have compiled information about the most important secondary metabolites of three important bacterial genera currently used in agriculture pest and disease management.
Assuntos
Bactérias/metabolismo , Agentes de Controle Biológico , Metabolismo Secundário , Agricultura/métodos , Bacillus/metabolismo , Produtos Agrícolas , Controle Biológico de Vetores , Pseudomonas/metabolismo , Serratia/metabolismoRESUMO
To maintain the world population demand, a sustainable agriculture is needed. Since current global vision is more friendly with the environment, eco-friendly alternatives are desirable. In this sense, plant growth-promoting rhizobacteria could be the choice for the management of soil-borne diseases of crop plants. These rhizobacteria secrete chemical compounds which act as phytohormones. Indole-3-acetic acid (IAA) is the most common plant hormone of the auxin class which regulates various processes of plant growth. IAA compound, in which structure can be found a carboxylic acid attached through a methylene group to the C-3 position of an indole ring, is produced both by plants and microorganisms. Plant growth-promoting rhizobacteria and fungi secrete IAA to promote the plant growth. In this review, IAA production and mechanisms of action by bacteria and fungi along with the metabolic pathways evolved in the IAA secretion and commercial prospects are revised.Key points⢠Many microorganisms produce auxins which help the plant growth promotion.⢠These auxins improve the plant growth by several mechanisms.⢠The auxins are produced through different mechanisms.
Assuntos
Ácidos Indolacéticos , Reguladores de Crescimento de Plantas , Agricultura , Desenvolvimento Vegetal , PlantasRESUMO
Chemical analysis of the crude extract of bacterial strain Bacillus amyloliquefaciens ELI149, which had been previously isolated from soil, resulted in the isolation and characterization of two known macrolactin derivatives, macrolactin A (1) and 7-O-succinyl macrolactin A (2). The structures of two compounds were assigned by 1D/2D NMR techniques. The two compounds were demonstrated antifungal activity against some important phytopathogens. However, the presence of the succinyl moiety at C-7 gives to the molecule more activity being the second compound more active than the first, showing for the first time, a structure/activity relationship. The cellular damage was also studied in two important phytopathogen fungi.
Assuntos
Antifúngicos , Bacillus amyloliquefaciens , Antibacterianos/farmacologia , Antifúngicos/farmacologia , MacrolídeosRESUMO
Synthetic chemical pesticides have been used for many years to increase the yield of agricultural crops. However, in the future, this approach is likely to be limited due to negative impacts on human health and the environment. Therefore, studies of the secondary metabolites produced by agriculturally important microorganisms have an important role in improving the quality of the crops entering the human food chain. In this review, we have compiled information about the most important secondary metabolites of fungal species currently used in agriculture pest and disease management.
Assuntos
Anti-Infecciosos/metabolismo , Agentes de Controle Biológico/metabolismo , Produtos Agrícolas/microbiologia , Fungos/metabolismo , Metabolismo Secundário , Agricultura , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Agentes de Controle Biológico/química , Agentes de Controle Biológico/farmacologia , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Fungos/classificação , Controle Biológico de Vetores , Praguicidas/química , Praguicidas/metabolismo , Praguicidas/farmacologiaRESUMO
Melanins are negatively-charged, hydrophobic, dark high molecular weight irregular biopolymers, composed of polymerized phenolic and/or indolic compounds. They are produced by most organisms. Bacillus thuringiensis is a Gram-positive, spore-forming, soil bacterium and the most successful biological control agent that produces distinctly shaped crystals during sporulation that have insecticidal activity. However, one of the main disadvantages is that the insecticidal activity of B. thuringiensis formulation is unstable and rapidly loses its activity under field conditions due to UV radiation. Melanin absorbs radiation; therefore photoprotection of B. thuringiensis based on melanin has been studied and is herewith reviewed.
Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Melaninas/metabolismo , Toxinas de Bacillus thuringiensis , Estabilidade de Medicamentos , Raios UltravioletaRESUMO
BACKGROUND: The total syntheses of complex natural products have evolved to include new methodologies to save time, simplifying the form to achieve these natural compounds. OBJECTIVES: In this review, we have described the asymmetric synthesis of different natural products and biologically active compounds of the last ten years until the current day. RESULTS: An asymmetric organocatalytic reaction is a key to generate stereoselectively the main structure with the required stereochemistry. CONCLUSION: Even more remarkable, the organocatalytic cascade reactions, which are carried out with high stereoselectivity, as well as a possible approximation of the organocatalysts activation with substrates are also described.
Assuntos
Produtos Biológicos , CatáliseRESUMO
BACKGROUND: Currently antibiotic resistant pathogenic bacteria are emerging as an important health problem worldwide. The search for new compounds with antibiotic characteristics is the most promising alternative. Bacteriocins are natural compounds that are inhibitory against pathogens, and Bacillus species are the major producers of these compounds, showing antimicrobial activity against clinically important bacteria. These peptides not only have potential in the pharmaceutical industry but also in food and agricultural sectors. OBJECTIVE: We provide an overview of the recent bacteriocins isolated from different species of Bacillus including their applications and older bacteriocins. RESULTS: In this review, we have revised some works about the improvements carried out in the production of bacteriocins. CONCLUSION: These applications make bacteriocins very promising compounds that need to study for industrial production.
Assuntos
Bacillus , Bacteriocinas , Antibacterianos/farmacologia , Bactérias , Bacteriocinas/farmacologia , HumanosRESUMO
Complete and balanced nutrition has always been the first line of plant defense due to the direct involvement of mineral elements in plant protection. Mineral elements affect plant health directly by modulating the activity of redox enzymes or improving the plant vigor indirectly by altering root exudates, and changing microflora population dynamics, rhizosphere soil nutrient content, pH fluctuation, lignin deposition, and phytoalexin biosynthesis. Nitrogen (N) is one of the most important macronutrients having a significant impact on the host-pathogen axis. N negatively affects the plant's physical defense along with the production of antimicrobial compounds, but it significantly alleviates defense-related enzyme levels that can eventually assist in systemic resistance. Potassium (K) is an essential plant nutrient, when it is present in adequate concentration, it can certainly increase the plant's polyphenolic concentrations, which play a critical role in the defense mechanism. Although no distinguished role of phosphorus (P) is observed in plant disease resistance, a high P content may increase the plant's susceptibility toward the invader. Manganese (Mn) is one of the most important micronutrients, which have a vital effect on photosynthesis, lignin biosynthesis, and other plant metabolic functions. Zinc (Zn) is a part of enzymes that are involved in auxin synthesis, infectivity, phytotoxin, and mycotoxin production in pathogenic microorganisms. Similarly, many other nutrients also have variable effects on enhancing or decreasing the host susceptibility toward disease onset and progression, thereby making integrative plant nutrition an indispensable component of sustainable agriculture. However, there are still many factors influencing the triple interaction of host-pathogen-mineral elements, which are not yet unraveled. Thereby, the present review has summarized the recent progress regarding the use of macro- and micronutrients in sustainable agriculture and their role in plant disease resistance.
RESUMO
Bacillus species produce secondary metabolites that are the object of natural product chemistry studies. The wide structural variability of these compounds has attracted the curiosity of chemists and their biological activities have inspired the pharmaceutical industry to search for lead structures in microbial extracts. Screening of microbial extracts reveals the large structural diversity of natural compounds with broad biological activities, such as antimicrobial, antiviral, immunosuppressive, and antitumor activities, that enable the bacterium to survive in its natural environment. These findings widen the potential industrial importance of Bacillus spp., particularly of B. thuringiensis, beyond insecticidal usage and may help explain the role of Bacillus spp. in the soil ecosystem.
Assuntos
Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bacillus/metabolismo , Microbiologia do SoloRESUMO
Induction of resistance to pathogen is associated with the colonization of root by Trichoderma spp. has been attributed as one of the major mechanisms contributing to pathogenic invasion. The present study sheds light on the defense network of brinjal plant bioprimed with Trichoderma spp. challenged with Sclerotinia sclerotiorum. Plants treated with dual inoculation of Trichoderma harzianum and Trichoderma asperellum triggered further synthesis of TPC under S. sclerotiorum challenge with maximum increment recorded at 72 hours. In consortium treated and pathogen challenged plants, a higher amount of shikimic acid was observed at 72 hours, whereas other phenolics showed little differences among the treatments. The consortium treatment showed significantly higher defense related enzymes (Phenylalanine Ammonia Lyase, Peroxidase and Polyphenol Oxidase) activity than other treatments. The study signifies how Trichoderma spp. reprograms the host's defense network to provide robust protection against S. sclerotiorum. In the present case, overall protection was provided to the brinjal plants against the attack of S. sclerotiorum.
RESUMO
Bacillus thuringiensis (Bt) has been used as a biopesticide in agriculture, forestry and mosquito control because of its advantages of specific toxicity against target insects, lack of polluting residues and safety to non-target organisms. The insecticidal properties of this bacterium are due to insecticidal proteins produced during sporulation. Despite these ecological benefits, the use of Bt biopesticides has lagged behind the synthetic chemicals. Genetic improvement of Bt natural strains, in particular Bt recombination, offers a promising means of improving efficacy and cost-effectiveness of Bt-based bioinsecticide products to develop new biotechnological applications.
Assuntos
Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/biossíntese , Vias Biossintéticas/genética , Endotoxinas/biossíntese , Engenharia Genética , Proteínas Hemolisinas/biossíntese , Insetos/microbiologia , Animais , Bacillus thuringiensis/patogenicidade , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Controle de Insetos/métodos , Controle Biológico de Vetores/métodos , Recombinação GenéticaRESUMO
The resistance among various microbial species (infectious agents) to different antimicrobial drugs has emerged as a cause of serious public health problem all over the world. In this sense, natural products have been a rich source of compounds for drug discovery with antibiotic activity. Macrolactins are amazing structures which have antibiotic activity against some clinically relevant pathogens. In addition, they have anti-inflammatory, antifungal, antimicrobial, and antitumor activities. They are macrolides containing 24-membered lactone ring with some differences in their chemical structures. The synthesis of these compounds is a difficult task which has attracted attention of researchers; however few syntheses have been reported. In this review, the isolation of all reported macrolactins, their syntheses and biological activities are revisited.
Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Macrolídeos/farmacologia , Neoplasias/tratamento farmacológico , Animais , Anti-Infecciosos/química , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Produtos Biológicos/química , Doenças Transmissíveis/tratamento farmacológico , Fungos/efeitos dos fármacos , Humanos , Macrolídeos/químicaRESUMO
Six known indole alkaloid derivatives have been isolated for the first time from Bacillus thuringiensis and Bacillus velezensis strains, all of them as building blocks for the synthesis of larger natural products. Their structure was elucidated by a complete spectroscopy. Their biological activities were tested against some Gram-positive and Gram-negative bacteria and three phytopathogenic fungi which cause diseases in important crops, such as Moniliophthora roreri, the causal agent of cacao disease. The results indicated that some compounds had modest antibacterial activity; however, some of them had strong antifungal activity against the probed fungi. This antifungal activity of these compounds has not been reported.
Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Bacillus thuringiensis/química , Bacillus/química , Alcaloides Indólicos/isolamento & purificação , Agaricales/efeitos dos fármacos , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Bacillus/metabolismo , Bacillus thuringiensis/metabolismo , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Alcaloides Indólicos/metabolismo , Alcaloides Indólicos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura MolecularRESUMO
Microorganisms are able to produce hundreds of unique chemical structures that can be effectively used by the human beings on their own benefit using the products in the chemical industry. Bacteria belonging to Bacillus genera are very good chemical factories capable to synthesize different compounds with a wide variety of activities. In this review, we try to review the compounds with their respective biological activities produced by different species of Bacillus.