Biocontrol Agents: Toolbox for the Screening of Weapons against Mycotoxigenic Fusarium

The aim of this study was to develop a set of experiments to screen and decipher the mechanisms of biocontrol agents (BCAs), isolated from commercial formulation, against two major mycotoxigenic fungi in cereals, Fusarium graminearum and Fusarium verticillioides. These two phytopathogens produce mycotoxins harmful to human and animal health and are responsible for the massive use of pesticides, for the protection of cereals. It is therefore essential to better understand the mechanisms of action of alternative control strategies such as the use of BCAs in order to optimize their applications. The early and late stages of interaction between BCAs and pathogens were investigated from germination of spores to the effects on perithecia (survival form of pathogen). The analysis of antagonist activities of BCAs revealed different strategies of biocontrol where chronological, process combination and specialization aspects of interactions are discussed. Streptomyces griseoviridis main strategy is based on antibiosis with the secretion of several compounds with anti-fungal and anti-germination activity, but also a mixture of hydrolytic enzymes to attack pathogens, which compensates for an important deficit in terms of spatial colonization capacity. It has good abilities in terms of nutritional competition. Trichoderma asperellum is capable of activating a very wide range of defenses and attacks combining the synthesis of various antifungal compounds (metabolite, enzymes, VOCs), with different targets (spores, mycelium, mycotoxins), and direct action by mycoparasitism and mycophagy. Concerning Pythium oligandrum, its efficiency is mainly due to its strong capacity to colonize the environment, with a direct action via microbial predation, stimulation of its reproduction at the contact of pathogens and the reduction of perithecia formation.

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Antifungal activities of thiosemicarbazones and semicarbazones against mycotoxigenic fungi

Ciência e Agrotecnologia ◽

10.1590/s1413-70542014000600001 ◽

2014 ◽

Vol 38 (6) ◽

pp. 531-537 ◽

Cited By ~ 6

Author(s):

Rojane de Oliveira Paiva ◽

Lucimar Ferreira Kneipp ◽

Carla Marins Goular ◽

Mariana Almeida Albuquerque ◽

Aurea Echevarria

Keyword(s):

Antifungal Activity ◽

Aspergillus Flavus ◽

Fungicidal Activity ◽

Fusarium Verticillioides ◽

Animal Health ◽

Fungistatic Activity ◽

Mycotoxigenic Fungi ◽

Quality Of Food ◽

Chelating Effect

Mycotoxigenic fungi can compromise the quality of food, exposing human and animal health at risk. The antifungal activity of eight thiosemicarbazones (1-8) and nine semicarbazones (9-17) was evaluated against Aspergillus flavus, A. nomius, A. ochraceus, A. parasiticus and Fusarium verticillioides. Thiosemicarbazones had MIC values of 125-500 µg/ml. The thiosemicarbazones 1 and 2 exerted fungistatic activity against Aspergillus spp., and thiosemicarbazone 2 exerted fungicidal activity against F. verticillioides. Compound 2 showed an iron chelating effect of 63%. The ergosterol content of A. parasiticus had a decrease of 28 and 71% for the 31.2 and 62.5 µg/ml concentrations of thiosemicarbazone 2 compared to the control. The obtained results of antifungal activity revealed that thiosemicarbazone class was more active when compared to semicarbazone class and, the thiosemicarbazone 2 was the most active compound, specially, against Aspergillus spp.

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In-Vitro Application of a Qatari Burkholderia cepacia strain (QBC03) in the Biocontrol of Mycotoxigenic Fungi and in the Reduction of Ochratoxin A biosynthesis by Aspergillus carbonarius

Toxins ◽

10.3390/toxins11120700 ◽

2019 ◽

Vol 11 (12) ◽

pp. 700 ◽

Cited By ~ 4

Author(s):

Randa Zeidan ◽

Zahoor Ul-Hassan ◽

Roda Al-Thani ◽

Quirico Migheli ◽

Samir Jaoua

Keyword(s):

Antifungal Activity ◽

Ochratoxin A ◽

Burkholderia Cepacia ◽

Culture Supernatant ◽

Animal Health ◽

Aspergillus Carbonarius ◽

Penicillium Verrucosum ◽

Wide Range ◽

Mycotoxigenic Fungi

Mycotoxins are secondary metabolites produced by certain filamentous fungi, causing human and animal health issues upon the ingestion of contaminated food and feed. Among the safest approaches to the control of mycotoxigenic fungi and mycotoxin detoxification is the application of microbial biocontrol agents. Burkholderia cepacia is known for producing metabolites active against a broad number of pathogenic fungi. In this study, the antifungal potential of a Qatari strain of Burkholderia cepacia (QBC03) was explored. QBC03 exhibited antifungal activity against a wide range of mycotoxigenic, as well as phytopathogenic, fungal genera and species. The QBC03 culture supernatant significantly inhibited the growth of Aspergillus carbonarius, Fusarium culmorum and Penicillium verrucosum in PDA medium, as well as A. carbonarius and P. verrucosum biomass in PDB medium. The QBC03 culture supernatant was found to dramatically reduce the synthesis of ochratoxin A (OTA) by A. carbonarius, in addition to inducing mycelia malformation. The antifungal activity of QBC03’s culture extract was retained following thermal treatment at 100 °C for 30 min. The findings of the present study advocate that QBC03 is a suitable biocontrol agent against toxigenic fungi, due to the inhibitory activity of its thermostable metabolites.

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Biological control of mycotoxin-producing molds

Ciência e Agrotecnologia ◽

10.1590/s1413-70542012000500001 ◽

2012 ◽

Vol 36 (5) ◽

pp. 483-497 ◽

Cited By ~ 22

Author(s):

Flávio Henrique Vasconcelos de Medeiros ◽

Samuel Julio Martins ◽

Tiago Domingues Zucchi ◽

Itamar Soares de Melo ◽

Luis Roberto Batista ◽

...

Keyword(s):

Biological Control ◽

Public Perception ◽

Fruits And Vegetables ◽

Control Strategies ◽

Animal Health ◽

Chemical Compounds ◽

The Public ◽

Mycotoxin Contamination ◽

Mycotoxigenic Fungi ◽

Food And Feed

Mycotoxins are produced by the secondary metabolism of many fungi and can be found in almost 25% of the world's agricultural commodities. These compounds are toxic to humans, animals, and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. Besides, up to 25% of all harvested fruits and vegetables are lost due to storage molds and/or mycotoxin contamination and many methods have been applied to mitigate these issues, but most of them rely on the use of fungicides. Although chemicals are often the first defensive line against mycotoxigenic fungi, the indiscriminate use of fungicides are awakening the public perception due to their noxious effects on the environment and human/animal health. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. In this background, biological control using microbial antagonists such as bacteria, fungi and yeasts have been shown to be a feasible substitute to reduce the use of chemical compounds. Despite of the positive findings using the biocontrol agents only a few products have been registered and are commercially available to control mycotoxin-producing fungi. This review brings about the up-to-date biological control strategies to prevent or reduce harvested commodity damages caused by storage fungi and the contamination of food and feed by mycotoxins.

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Recent Advances in Mycotoxin Analysis and Detection of Mycotoxigenic Fungi in Grapes and Derived Products

Sustainability ◽

10.3390/su13052537 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2537

Author(s):

Dimosthenis Kizis ◽

Aikaterini-Eleni Vichou ◽

Pantelis I. Natskoulis

Keyword(s):

Filamentous Fungi ◽

Animal Health ◽

Fungal Species ◽

Molecular Assays ◽

Economic Threat ◽

Wide Range ◽

Mycotoxigenic Fungi ◽

Mycotoxin Analysis ◽

Methodological Approaches ◽

Processed Products

Mycotoxins are secondary metabolites of filamentous fungi that can cause toxic effects in human and animal health. Most of the filamentous fungi that produce these mycotoxins belong to four genera, namely, Aspergillus, Penicillium, Fusarium, and Alternaria. Mycotoxigenic fungi, along with mycotoxins, create a constant and serious economic threat for agriculture in many terms, counting product losses due to crop contamination and food spoilage, as well malnutrition when considering nutritional quality degradation. Given the importance of robust and precise diagnostics of mycotoxins and the related producing fungi in the grape food chain, one of the most important agricultural sectors worldwide, the present review initially delivers a comprehensive presentation of mycotoxin reports on grape and derived products, including a wide range of commodities such as fresh grapes, raisins, wine, juices, and other processed products. Next, based on worldwide regulations’ requirements for mycotoxins, and referring to the relative literature, this work presents methodological approaches for mycotoxin determination, and stresses major methods for the detection of fungal species responsible for mycotoxin production. The principle of function and basic technical background on the available analytical and molecular biology techniques developed—including chromatography, mass spectrometry, immunochemical-based assays, biosensors, and molecular assays—is briefly given, and references for their application to grape and derived product testing are highlighted.

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Associated microflora of medicinal ferns: biotechnological potentials and possible applications

International Journal of Bioassays ◽

10.21746/ijbio.2016.03.0017 ◽

2016 ◽

Vol 5 (03) ◽

pp. 4927 ◽

Cited By ~ 3

Author(s):

Shubhi Srivastava ◽

Paul A. K.

Keyword(s):

Secondary Metabolites ◽

Growth Promotion ◽

Biological Activities ◽

Hydrolytic Enzymes ◽

In Vitro Production ◽

Wide Range ◽

Negative Effect ◽

Bacteria And Fungi

Plant associated microorganisms that colonize the upper and internal tissues of roots, stems, leaves and flowers of healthy plants without causing any visible harmful or negative effect on their host. Diversity of microbes have been extensively studied in a wide variety of vascular plants and shown to promote plant establishment, growth and development and impart resistance against pathogenic infections. Ferns and their associated microbes have also attracted the attention of the scientific communities as sources of novel bioactive secondary metabolites. The ferns and fern alleles, which are well adapted to diverse environmental conditions, produce various secondary metabolites such as flavonoids, steroids, alkaloids, phenols, triterpenoid compounds, variety of amino acids and fatty acids along with some unique metabolites as adaptive features and are traditionally used for human health and medicine. In this review attention has been focused to prepare a comprehensive account of ethnomedicinal properties of some common ferns and fern alleles. Association of bacteria and fungi in the rhizosphere, phyllosphere and endosphere of these medicinally important ferns and their interaction with the host plant has been emphasized keeping in view their possible biotechnological potentials and applications. The processes of host-microbe interaction leading to establishment and colonization of endophytes are less-well characterized in comparison to rhizospheric and phyllospheric microflora. However, the endophytes are possessing same characteristics as rhizospheric and phyllospheric to stimulate the in vivo synthesis as well as in vitro production of secondary metabolites with a wide range of biological activities such as plant growth promotion by production of phytohormones, siderophores, fixation of nitrogen, and phosphate solubilization. Synthesis of pharmaceutically important products such as anticancer compounds, antioxidants, antimicrobials, antiviral substances and hydrolytic enzymes could be some of the promising areas of research and commercial exploitation.

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Marine Organisms for the Sustainable Management of Plant Parasitic Nematodes

Plants ◽

10.3390/plants10020369 ◽

2021 ◽

Vol 10 (2) ◽

pp. 369

Author(s):

Pasqua Veronico ◽

Maria Teresa Melillo

Keyword(s):

Crop Production ◽

Control Strategies ◽

Marine Organisms ◽

New Drugs ◽

Effective Control ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Wide Range ◽

Plant Growth Stimulants ◽

Plant Parasitic

Plant parasitic nematodes are annually responsible for the loss of 10%–25% of worldwide crop production, most of which is attributable to root-knot nematodes (RKNs) that infest a wide range of agricultural crops throughout the world. Current nematode control tools are not enough to ensure the effective management of these parasites, mainly due to the severe restrictions imposed on the use of chemical pesticides. Therefore, it is important to discover new potential nematicidal sources that are suitable for the development of additional safe and effective control strategies. In the last few decades, there has been an explosion of information about the use of seaweeds as plant growth stimulants and potential nematicides. Novel bioactive compounds have been isolated from marine cyanobacteria and sponges in an effort to find their application outside marine ecosystems and in the discovery of new drugs. Their potential as antihelmintics could also be exploited to find applicability against plant parasitic nematodes. The present review focuses on the activity of marine organisms on RKNs and their potential application as safe nematicidal agents.

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Wolbachia: endosymbiont of onchocercid nematodes and their vectors

Parasites & Vectors ◽

10.1186/s13071-021-04742-1 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Ranju Ravindran Santhakumari Manoj ◽

Maria Stefania Latrofa ◽

Sara Epis ◽

Domenico Otranto

Keyword(s):

Control Strategies ◽

Molecular Data ◽

Scientific Data ◽

Growth And Survival ◽

Vector Borne Diseases ◽

Wide Range ◽

Veterinary Importance ◽

Wolbachia Endosymbiont ◽

Vector Borne ◽

And Control

Abstract Background Wolbachia is an obligate intracellular maternally transmitted, gram-negative bacterium which forms a spectrum of endosymbiotic relationships from parasitism to obligatory mutualism in a wide range of arthropods and onchocercid nematodes, respectively. In arthropods Wolbachia produces reproductive manipulations such as male killing, feminization, parthenogenesis and cytoplasmic incompatibility for its propagation and provides an additional fitness benefit for the host to protect against pathogens, whilst in onchocercid nematodes, apart from the mutual metabolic dependence, this bacterium is involved in moulting, embryogenesis, growth and survival of the host. Methods This review details the molecular data of Wolbachia and its effect on host biology, immunity, ecology and evolution, reproduction, endosymbiont-based treatment and control strategies exploited for filariasis. Relevant peer-reviewed scientic papers available in various authenticated scientific data bases were considered while writing the review. Conclusions The information presented provides an overview on Wolbachia biology and its use in the control and/or treatment of vectors, onchocercid nematodes and viral diseases of medical and veterinary importance. This offers the development of new approaches for the control of a variety of vector-borne diseases. Graphic Abstract

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Risk factors associated with Ctenocephalides felis flea infestation of peri-urban goats: a neglected parasite in an under-appreciated host

Tropical Animal Health and Production ◽

10.1007/s11250-021-02620-7 ◽

2021 ◽

Vol 53 (1) ◽

Author(s):

Julia Rose Dahm ◽

Jordana Burdon Bailey ◽

Robert F. Kelly ◽

Patrick Chikungwa ◽

Julius Chulu ◽

...

Keyword(s):

Risk Factors ◽

Urban Communities ◽

Control Strategies ◽

Animal Health ◽

Animal Husbandry ◽

Ctenocephalides Felis ◽

Disease Spread ◽

Health Concern ◽

Cross Sectional ◽

Flea Infestation

AbstractGoats are critical in mixed smallholder agricultural systems in lower and middle-income countries, while fleas are important human and animal health concerns around the world. Convenience sampling was used to describe and consider risk factors for flea infestations of peri-urban goats, with the aim of informing the iterative development of animal husbandry and management based control strategies. Seven hundred and ninety-two goats were examined in 228 households across 10 peri-urban communities surrounding Blantyre in southern Malawi. The prevalence of Ctenocephalides felis fleas was 18.3, 37.1 and 100% at the levels of individual goats, households and communities, respectively, highlighting a neglected human and animal health concern. Constant introduction of new livestock coupled to a lack of biosecurity within communities, the ubiquitous presence of dog and cat hosts for C. felis, the frequency and thoroughness of cleaning overnight goat accommodation, and goat age less than 12 months old were identified as risk factors for flea infestation. This focal cross-sectional study highlights the significance of fleas in peri-urban communities and uncovers trends and commonalities that are needed to inform sustainable disease management. The majority of the peri-urban goat keepers were female, had resided in the same community throughout their whole life and had primary level education. Advice on the planned management of fleas in livestock needs to be tailored towards this demographic group. This approach affords an opportunity to promote public health measures to address household flea infestations and zoonotic disease spread.

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168 The effects of fly control strategies on fly abundance, fly avoidance behaviors, and performance in feedlot bulls and steers

Journal of Animal Science ◽

10.1093/jas/skz397.034 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 15-16

Author(s):

Courtney McNeff ◽

Justin Talley ◽

Colton A Robison ◽

Blake K Wilson

Keyword(s):

Treatment Time ◽

Control Strategies ◽

Block Design ◽

Animal Health ◽

Piperonyl Butoxide ◽

Stable Fly ◽

Animal Performance ◽

Time Interaction ◽

Avoidance Behaviors ◽

Fly Control

Abstract The objective of this experiment was to examine the effects of fly control strategies on fly abundance, fly avoidance behaviors, and animal performance in a feedlot setting. Angus bulls (n = 64; BW = 281 ± 36.2 kg) and steers (n = 36; BW = 475 ± 40.4 kg) were blocked by sex and BW and assigned to 1 of 4 experimental treatments in a randomized complete block design (7 pens/treatment; 4 bulls/pen; 3 steers/pen). Treatments included: control (CON; no fly control), abamectin, piperonyl butoxide, and zetacypermethrin insecticide tags (FT; Tri-Zap®, Y-Tex Corporation, Cody, WY), permethrin and piperonyl butoxide pour on (PO; Permectrin® CDS, Bayer Animal Health, Shawnee Mission, KS), or a garlic-powder top dress (GR) administered at 0.28 g •-1 animal •-1d. The experiment was conducted between June and September. Horn and stable fly abundance (FA) and fly avoidance behaviors (FAB; i.e. tail-flicks, stomping, head-tossing) were recorded by trained personnel. Both FA and FAB were recorded once/wk on days with similar temperatures, humidity, wind speed, and without precipitation based on Oklahoma Mesonet data (Stillwater site). There was a tendency for a treatment × time interaction for horn FA with differences in treatments occurring at wk 1, 2, 8, and 14. There was no treatment × time interaction for stable FA or FAB, however both were affected by time (P < 0.001). There were no differences in final BW (P = 0.34), overall ADG (P = 0.30), overall DMI (P = 0.53), or overall G:F (P = 0.39). There was a tendency (P ≤ 0.10) for GR to have decreased BW on d 28 and decreased ADG from d 0 to 28 compared to FT and PO. There was also a tendency (P = 0.09) for decreased DMI from d 0 to 56 for GR compared to CON and FT. Overall FA was less than expected (mean = 1 to 17 flies/animal) throughout the experiment and overall animal performance was unaffected by fly control strategy.

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Secretory Proteases of the Human Skin Microbiome

Infection and Immunity ◽

10.1128/iai.00397-21 ◽

2021 ◽

Author(s):

Wisely Chua ◽

Si En Poh ◽

Hao Li

Keyword(s):

Human Skin ◽

Hydrolytic Enzymes ◽

Microbial Interactions ◽

Skin Microbiome ◽

Protein Cleavage ◽

Wide Range ◽

Range Of Functions ◽

Diverse Community ◽

Secreted Proteases ◽

Pathogenic Agents

The human skin is our outermost layer and serves as a protective barrier against external insults. Advances in next generation sequencing have enabled the discoveries of a rich and diverse community of microbes - bacteria, fungi and viruses that are residents of this surface. The genomes of these microbes also revealed the presence of many secretory enzymes. In particular, proteases which are hydrolytic enzymes capable of protein cleavage and degradation are of special interest in the skin environment which is enriched in proteins and lipids. In this minireview, we will focus on the roles of these skin-relevant microbial secreted proteases, both in terms of their widely studied roles as pathogenic agents in tissue invasion and host immune inactivation, and their recently discovered roles in inter-microbial interactions and modulation of virulence factors. From these studies, it has become apparent that while microbial proteases are capable of a wide range of functions, their expression is tightly regulated and highly responsive to the environments the microbes are in. With the introduction of new biochemical and bioinformatics tools to study protease functions, it will be important to understand the roles played by skin microbial secretory proteases in cutaneous health, especially the less studied commensal microbes with an emphasis on contextual relevance.

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