Microbiological contamination of feed – current hazards and new challenges

Feed microflora remains a very complex and still largely uncharacterized ecosystem. Given the wide range of potential sources of microbial contamination that may come into contact with feed, a variety of microorganisms, including pathogenic ones, can be expected. Microbiological contamination of feeds depends on environmental factors, which are a natural, primary source related to the microflora carried on feed materials and coming from soil, water and air. Microbial contamination may also emerge secondarily in the processing and distribution stages of feed, but also in the breeding stage, where feed may be contaminated by animals showing disease symptoms or asymptomatically. A wide variety of pathogenic microorganisms that are transmitted symptomatically or asymptomatically can cause economic losses to feed producers and farmers, and some of them due to their zoonotic nature can also pose a potential risk to consumers. New feed materials appear on the market, i.e. Insect Processed Animal Proteins, which are part of the strategy of replacing traditional protein sources. These materials are under investigation for their benefits as well as for microbiological safety. The aim of this review was to present the current knowledge on the main microbiological risk factors influencing the quality and safety of feed, as well as new analytical challenges related to the introduction of new feed materials.

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Harnessing symbiotic plant–fungus interactions to unleash hidden forces from extreme plant ecosystems

Journal of Experimental Botany ◽

10.1093/jxb/eraa040 ◽

2020 ◽

Vol 71 (13) ◽

pp. 3865-3877 ◽

Cited By ~ 3

Author(s):

Marta-Marina Pérez-Alonso ◽

Carmen Guerrero-Galán ◽

Sandra S Scholz ◽

Takatoshi Kiba ◽

Hitoshi Sakakibara ◽

...

Keyword(s):

Climate Change ◽

Global Climate Change ◽

Production Systems ◽

Current Knowledge ◽

Global Climate ◽

Close Association ◽

Economic Losses ◽

Plant Interactions ◽

Wide Range ◽

Agricultural Innovations

Abstract Global climate change is arguably one of the biggest threats of modern times and has already led to a wide range of impacts on the environment, economy, and society. Owing to past emissions and climate system inertia, global climate change is predicted to continue for decades even if anthropogenic greenhouse gas emissions were to stop immediately. In many regions, such as central Europe and the Mediterranean region, the temperature is likely to rise by 2–5 °C and annual precipitation is predicted to decrease. Expected heat and drought periods followed by floods, and unpredictable growing seasons, are predicted to have detrimental effects on agricultural production systems, causing immense economic losses and food supply problems. To mitigate the risks of climate change, agricultural innovations counteracting these effects need to be embraced and accelerated. To achieve maximum improvement, the required agricultural innovations should not focus only on crops but rather pursue a holistic approach including the entire ecosystem. Over millions of years, plants have evolved in close association with other organisms, particularly soil microbes that have shaped their evolution and contemporary ecology. Many studies have already highlighted beneficial interactions among plants and the communities of microorganisms with which they coexist. Questions arising from these discoveries are whether it will be possible to decipher a common molecular pattern and the underlying biochemical framework of interspecies communication, and whether such knowledge can be used to improve agricultural performance under environmental stress conditions. In this review, we summarize the current knowledge of plant interactions with fungal endosymbionts found in extreme ecosystems. Special attention will be paid to the interaction of plants with the symbiotic root-colonizing endophytic fungus Serendipita indica, which has been developed as a model system for beneficial plant–fungus interactions.

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DISINFEKSI UNTUK PROSES PENGOLAHAN AIR MINUM

Jurnal Air Indonesia ◽

10.29122/jai.v3i1.2314 ◽

2018 ◽

Vol 3 (1) ◽

Author(s):

Nusa Idaman Said

Keyword(s):

Drinking Water ◽

Water Purification ◽

Distribution System ◽

Residual Effect ◽

Drinking Water Treatment ◽

Disinfection Byproducts ◽

Water Disinfection ◽

Pathogenic Microorganisms ◽

Microbiological Contamination ◽

Disinfection Process

Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water, drinking water usage will cause people to fall ill. Chemical inactivation of microbiological contamination in natural or untreated water is usually one of the final steps to reduce pathogenic microorganisms in drinking water. Combinations of water purification steps (oxidation, coagulation, settling, disinfection, and filtration) cause (drinking) water to be safe after production. As an extra measure many countries apply a second disinfection step at the end of the water purification process, in order to protect the water from microbiological contamination in the water distribution system. Usually one uses a different kind of disinfectant from the one earlier in the process, during this disinfection process. The secondary disinfection makes sure that bacteria will not multiply in the water during distribution. This paper describes several technique of disinfection process for drinking water treatment. Disinfection can be attained by means of physical or chemical disinfectants. The agents also remove organic contaminants from water, which serve as nutrients or shelters for microorganisms. Disinfectants should not only kill microorganisms. Disinfectants must also have a residual effect, which means that they remain active in the water after disinfection. For chemical disinfection of water the following disinfectants can be used such as Chlorine (Cl2), Hypo chlorite (OCl-), Chloramines, Chlorine dioxide (ClO2), Ozone (O3), Hydrogen peroxide etch. For physical disinfection of water the following disinfectants can be used is Ultraviolet light (UV). Every technique has its specific advantages and and disadvantages its own application area sucs as environmentally friendly, disinfection byproducts, effectivity, investment, operational costs etc. Kata Kunci : Disinfeksi, bakteria, virus, air minum, khlor, hip khlorit, khloramine, khlor dioksida, ozon, UV.

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Fitness of Herbicide-Resistant Weeds: Current Knowledge and Implications for Management

Plants ◽

10.3390/plants8110469 ◽

2019 ◽

Vol 8 (11) ◽

pp. 469 ◽

Cited By ~ 5

Author(s):

Vila-Aiub

Keyword(s):

Life History ◽

Herbicide Resistance ◽

Management Practices ◽

Current Knowledge ◽

Resistance Management ◽

Fitness Cost ◽

Plant Fitness ◽

Resistance Mutations ◽

Fitness Costs ◽

Wide Range

Herbicide resistance is the ultimate evidence of the extraordinary capacity of weeds to evolve under stressful conditions. Despite the extraordinary plant fitness advantage endowed by herbicide resistance mutations in agroecosystems under herbicide selection, resistance mutations are predicted to exhibit an adaptation cost (i.e., fitness cost), relative to the susceptible wild-type, in herbicide untreated conditions. Fitness costs associated with herbicide resistance mutations are not universal and their expression depends on the particular mutation, genetic background, dominance of the fitness cost, and environmental conditions. The detrimental effects of herbicide resistance mutations on plant fitness may arise as a direct impact on fitness-related traits and/or coevolution with changes in other life history traits that ultimately may lead to fitness costs under particular ecological conditions. This brings the idea that a “lower adaptive value” of herbicide resistance mutations represents an opportunity for the design of resistance management practices that could minimize the evolution of herbicide resistance. It is evident that the challenge for weed management practices aiming to control, minimize, or even reverse the frequency of resistance mutations in the agricultural landscape is to “create” those agroecological conditions that could expose, exploit, and exacerbate those life history and/or fitness traits affecting the evolution of herbicide resistance mutations. Ideally, resistance management should implement a wide range of cultural practices leading to environmentally mediated fitness costs associated with herbicide resistance mutations.

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Toxin Production in Soybean (Glycine max L.) Plants with Charcoal Rot Disease and by Macrophomina phaseolina, the Fungus that Causes the Disease

Toxins ◽

10.3390/toxins11110645 ◽

2019 ◽

Vol 11 (11) ◽

pp. 645 ◽

Cited By ~ 8

Author(s):

Hamed K. Abbas ◽

Nacer Bellaloui ◽

Cesare Accinelli ◽

James R. Smith ◽

W. Thomas Shier

Keyword(s):

Culture Media ◽

Leaf Disc ◽

Toxin Production ◽

Macrophomina Phaseolina ◽

Economic Losses ◽

Limit Of Quantification ◽

Charcoal Rot ◽

Wide Range ◽

Soybean Plants ◽

Rot Disease

Charcoal rot disease, caused by the fungus Macrophomina phaseolina, results in major economic losses in soybean production in southern USA. M. phaseolina has been proposed to use the toxin (-)-botryodiplodin in its root infection mechanism to create a necrotic zone in root tissue through which fungal hyphae can readily enter the plant. The majority (51.4%) of M. phaseolina isolates from plants with charcoal rot disease produced a wide range of (-)-botryodiplodin concentrations in a culture medium (0.14–6.11 µg/mL), 37.8% produced traces below the limit of quantification (0.01 µg/mL), and 10.8% produced no detectable (-)-botryodiplodin. Some culture media with traces or no (-)-botryodiplodin were nevertheless strongly phytotoxic in soybean leaf disc cultures, consistent with the production of another unidentified toxin(s). Widely ranging (-)-botryodiplodin levels (traces to 3.14 µg/g) were also observed in the roots, but not in the aerial parts, of soybean plants naturally infected with charcoal rot disease. This is the first report of (-)-botryodiplodin in plant tissues naturally infected with charcoal rot disease. No phaseolinone was detected in M. phaseolina culture media or naturally infected soybean tissues. These results are consistent with (-)-botryodiplodin playing a role in the pathology of some, but not all, M. phaseolina isolates from soybeans with charcoal rot disease in southern USA.

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Transfer of Plasmid DNA to Clinical Coagulase-Negative Staphylococcal Pathogens by Using a Unique Bacteriophage

Applied and Environmental Microbiology ◽

10.1128/aem.04190-14 ◽

2015 ◽

Vol 81 (7) ◽

pp. 2481-2488 ◽

Cited By ~ 19

Author(s):

Volker Winstel ◽

Petra Kühner ◽

Bernhard Krismer ◽

Andreas Peschel ◽

Holger Rohde

Keyword(s):

Plasmid Dna ◽

Genetic Manipulation ◽

Current Knowledge ◽

Virulence Determinants ◽

Coagulase Negative Staphylococci ◽

Reliable Technique ◽

Content Type ◽

Research Activities ◽

Wide Range ◽

Genetic Barriers

ABSTRACTGenetic manipulation of emerging bacterial pathogens, such as coagulase-negative staphylococci (CoNS), is a major hurdle in clinical and basic microbiological research. Strong genetic barriers, such as restriction modification systems or clustered regularly interspaced short palindromic repeats (CRISPR), usually interfere with available techniques for DNA transformation and therefore complicate manipulation of CoNS or render it impossible. Thus, current knowledge of pathogenicity and virulence determinants of CoNS is very limited. Here, a rapid, efficient, and highly reliable technique is presented to transfer plasmid DNA essential for genetic engineering to important CoNS pathogens from a uniqueStaphylococcus aureusstrain via a specificS. aureusbacteriophage, Φ187. Even strains refractory to electroporation can be transduced by this technique once donor and recipient strains share similar Φ187 receptor properties. As a proof of principle, this technique was used to delete the alternative transcription factor sigma B (SigB) via allelic replacement in nasal and clinicalStaphylococcus epidermidisisolates at high efficiencies. The described approach will allow the genetic manipulation of a wide range of CoNS pathogens and might inspire research activities to manipulate other important pathogens in a similar fashion.

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Hidden Host Plant Associations of Soilborne Fungal Pathogens: An Ecological Perspective

Phytopathology ◽

10.1094/phyto-08-12-0192-le ◽

2013 ◽

Vol 103 (6) ◽

pp. 538-544 ◽

Cited By ~ 86

Author(s):

Glenna M. Malcolm ◽

Gretchen A. Kuldau ◽

Beth K. Gugino ◽

María del Mar Jiménez-Gasco

Keyword(s):

Host Plant ◽

Population Biology ◽

Fungal Pathogens ◽

Current Knowledge ◽

Vascular Plant ◽

Disease Symptoms ◽

Nonhost Plant ◽

Plant Associations ◽

Definition Of ◽

Forest Plants

Much of the current knowledge on population biology and ecology of soilborne fungal pathogens has been derived from research based on populations recovered from plants displaying disease symptoms or soil associated with symptomatic plants. Many soilborne fungal pathogens are known to cause disease on a large number of crop plants, including a variety of important agronomical, horticultural, ornamental, and forest plants species. For instance, the fungus Verticillium dahliae causes disease on >400 host plants. From a phytopathological perspective, plants on which disease symptoms have not been yet observed are considered to be nonhosts for V. dahliae. This term may be misleading because it does not provide information regarding the nature of the plant–fungus association; that is, a nonhost plant may harbor the fungus as an endophyte. Yet, there are numerous instances in the literature where V. dahliae has been isolated from asymptomatic plants; thus, these plants should be considered hosts. In this article, we synthesize scattered research that indicates that V. dahliae, aside from being a successful and significant vascular plant pathogen, may have a cryptic biology on numerous asymptomatic plants as an endophyte. Thus, we suggest here that these endophytic associations among V. dahliae and asymptomatic plants are not unusual relationships in nature. We propose to embrace the broader ecology of many fungi by differentiating between “symptomatic hosts” as those plants in which the infection and colonization by a fungus results in disease, and “asymptomatic hosts” as those plants that harbor the fungus endophytically and are different than true nonhosts that should be used for plant species that do not interact with the given fungus. In fact, if we broaden our definition of “host plant” to include asymptomatic plants that harbor the fungus as an endophyte, it is likely that the host ranges for some soilborne fungal pathogens are much larger than previously envisioned. By ignoring the potential for soilborne fungal pathogens to display endophytic relationships, we leave gaps in our knowledge about the population biology and ecology, persistence, and spread of these fungi in agroecosystems.

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The Effect of Gut Bacteria on the Physiology of Red Palm Weevil, Rhynchophorus ferrugineus Olivier and Their Potential for the Control of This Pest

Insects ◽

10.3390/insects12070594 ◽

2021 ◽

Vol 12 (7) ◽

pp. 594

Author(s):

Qian-Xia Liu ◽

Zhi-Ping Su ◽

Hui-Hui Liu ◽

Sheng-Ping Lu ◽

Bing Ma ◽

...

Keyword(s):

Molecular Mechanisms ◽

Current Knowledge ◽

Management Strategies ◽

Gut Bacteria ◽

Economic Losses ◽

Rhynchophorus Ferrugineus ◽

Intestinal Immunity ◽

Red Palm Weevil ◽

Nutrient Metabolism ◽

Palm Weevil

Red Palm Weevil (RPW), Rhynchophorus ferrugineus Olivier, is a notorious pest, which infests palm trees and has caused great economic losses worldwide. At present, insecticide applications are still the main way to control this pest. However, pesticide resistance has been detected in the field populations of RPW. Thus, future management strategies based on the novel association biological control need be developed. Recent studies have shown that the intestinal tract of RPW is often colonized by multiple microbial species as mammals and model insects, and gut bacteria have been found to promote the growth, development and immune activity of RPW larvae by modulating nutrient metabolism. Furthermore, two peptidoglycan recognition proteins (PGRPs), PGRP-LB and PGRP-S1, can act as the negative regulators to modulate the intestinal immunity to maintain the homeostasis of gut bacteria in RPW larvae. Here, we summarized the current knowledge on the gut bacterial composition of RPW and their impact on the physiological traits of RPW larvae. In contrast with metazoans, it is much easier to make genetic engineered microbes to produce some active molecules against pests. From this perspective, because of the profound effects of gut bacteria on host phenotypes, it is promising to dissect the molecular mechanisms behind their effect on host physiology and facilitate the development of microbial resource-based management methods for pest control.

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Molecular Subtyping of Blastocystis sp. Isolated from Farmed Animals in Southern Italy

Microorganisms ◽

10.3390/microorganisms9081656 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1656

Author(s):

Simona Gabrielli ◽

Marialetizia Palomba ◽

Federica Furzi ◽

Emanuele Brianti ◽

Gabriella Gaglio ◽

...

Keyword(s):

Current Knowledge ◽

Pcr Amplification ◽

Epidemiological Studies ◽

Fallow Deer ◽

Small Subunit ◽

Zoonotic Transmission ◽

Ssu Rrna ◽

Molecular Approaches ◽

Wide Range ◽

Blastocystis Sp

Blastocystis is a common intestinal protist distributed worldwide, infecting humans and a wide range of domestic and wild animals. It exhibits an extensive genetic diversity and, so far, 25 distinct small subunit ribosomal RNA (SSU rRNA) lineages termed subtypes (STs)) have been characterized; among them, 12 have thus far been reported in humans. The aims of the present study were to detect and genetically characterize Blastocystis sp. in synantropic animals to improve our current knowledge on the distribution and zoonotic transmission of Blastocystis STs in Italy. Samples were collected from N = 193 farmed animals and submitted to DNA extraction and PCR amplification of the SSU rRNA. Blastocystis was detected in 60 samples (31.08%) and successfully subtyped. Phylogenetic analysis evidenced that the isolates from fallow deer, goats, and pigs (N = 9) clustered within the ST5; those from pheasants (N = 2) in the ST6; those from chickens (N = 8) in the ST7; those from sheep (N = 6) in the ST10; and those from water buffaloes (N = 9) in the ST14 clade. The comparison between the present isolates from animals and those previously detected in humans in Italy suggested the animal-to-human spillover for ST6 and ST7. The present study represents the widest Blastocystis survey performed thus far in farmed animals in Italy. Further epidemiological studies using molecular approaches are required to determine the occurrence and distribution of Blastocystis STs in other potential animal reservoirs in Italy and to define the pathways of zoonotic transmission.

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Integration of early disease-resistance phenotyping, histological characterization, and transcriptome sequencing reveals insights into downy mildew resistance in impatiens

Horticulture Research ◽

10.1038/s41438-021-00543-w ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Ze Peng ◽

Yanhong He ◽

Saroj Parajuli ◽

Qian You ◽

Weining Wang ◽

...

Keyword(s):

Disease Resistance ◽

Downy Mildew ◽

Transcriptome Sequencing ◽

Early Stage ◽

Economic Losses ◽

Potential Candidate ◽

Early Disease ◽

True Leaf ◽

Cotyledon Stage ◽

Wide Range

AbstractDowny mildew (DM), caused by obligate parasitic oomycetes, is a destructive disease for a wide range of crops worldwide. Recent outbreaks of impatiens downy mildew (IDM) in many countries have caused huge economic losses. A system to reveal plant–pathogen interactions in the early stage of infection and quickly assess resistance/susceptibility of plants to DM is desired. In this study, we established an early and rapid system to achieve these goals using impatiens as a model. Thirty-two cultivars of Impatiens walleriana and I. hawkeri were evaluated for their responses to IDM at cotyledon, first/second pair of true leaf, and mature plant stages. All I. walleriana cultivars were highly susceptible to IDM. While all I. hawkeri cultivars were resistant to IDM starting at the first true leaf stage, many (14/16) were susceptible to IDM at the cotyledon stage. Two cultivars showed resistance even at the cotyledon stage. Histological characterization showed that the resistance mechanism of the I. hawkeri cultivars resembles that in grapevine and type II resistance in sunflower. By integrating full-length transcriptome sequencing (Iso-Seq) and RNA-Seq, we constructed the first reference transcriptome for Impatiens comprised of 48,758 sequences with an N50 length of 2060 bp. Comparative transcriptome and qRT-PCR analyses revealed strong candidate genes for IDM resistance, including three resistance genes orthologous to the sunflower gene RGC203, a potential candidate associated with DM resistance. Our approach of integrating early disease-resistance phenotyping, histological characterization, and transcriptome analysis lay a solid foundation to improve DM resistance in impatiens and may provide a model for other crops.

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Recent Development on Plant Aldehyde Dehydrogenase Enzymes and Their Functions in Plant Development and Stress Signaling

Genes ◽

10.3390/genes12010051 ◽

2020 ◽

Vol 12 (1) ◽

pp. 51

Author(s):

Adesola J. Tola ◽

Amal Jaballi ◽

Hugo Germain ◽

Tagnon D. Missihoun

Keyword(s):

Plant Development ◽

Critical Analysis ◽

Current Knowledge ◽

Stress Signaling ◽

Oxygen Species ◽

Abiotic And Biotic Stresses ◽

Aldehyde Dehydrogenases ◽

Biotic Stresses ◽

Wide Range ◽

Excessive Accumulation

Abiotic and biotic stresses induce the formation of reactive oxygen species (ROS), which subsequently causes the excessive accumulation of aldehydes in cells. Stress-derived aldehydes are commonly designated as reactive electrophile species (RES) as a result of the presence of an electrophilic α, β-unsaturated carbonyl group. Aldehyde dehydrogenases (ALDHs) are NAD(P)+-dependent enzymes that metabolize a wide range of endogenous and exogenous aliphatic and aromatic aldehyde molecules by oxidizing them to their corresponding carboxylic acids. The ALDH enzymes are found in nearly all organisms, and plants contain fourteen ALDH protein families. In this review, we performed a critical analysis of the research reports over the last decade on plant ALDHs. Newly discovered roles for these enzymes in metabolism, signaling and development have been highlighted and discussed. We concluded with suggestions for future investigations to exploit the potential of these enzymes in biotechnology and to improve our current knowledge about these enzymes in gene signaling and plant development.

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