In Vitro Analysis of the Antagonistic Biological and Chemical Interactions between the Endophyte Sordaria tomento-alba and the Phytopathogen Botrytis cinerea.

Plant pathogenic infections causing substantial global food losses are a persistent challenge. This study investigates a potential biocontrol strategy against the necrotrophic fungus Botrytis cinerea using the endophytic fungus Sordaria tomento-alba isolated from Gliricidia sepium in Colombia. Today, synthetic fungicides dominate B. cinerea control, raising environmental and health concerns. S. tomento-alba exhibits notable in vitro effects, inhibiting B. cinerea growth by approximately 60% during co-culture and 50% in double disc co-culture. Additionally, it suppresses botryanes production and produces the compound heptacyclosordariolone, which has proven effective in inhibiting B. cinerea mycelial growth and spore germination in vitro. This biocontrol agent could be a potential eco-friendly alternative to replace synthetic fungicides. Our study provides insights into the chemical and biological mechanisms underpinning the antagonistic activity of S. tomento-alba, emphasizing the need for further research to understand its biosynthesis pathways and optimize its biocontrol potential. It also contributes molecular evidence of fungal interactions with implications for advanced forums in molecular studies in biology and chemistry, particularly in addressing plant pathogenic infections and promoting sustainable agriculture.

In Vitro Studies of Endophytic Bacteria Isolated from Ginger (Zingiber officinale) as Potential Plant-Growth-Promoting and Biocontrol Agents against Botrytis cinerea and Colletotrichum acutatum.

Agriculture currently confronts a multitude of challenges arising from the excessive utilization of chemical pesticides and the proliferation of phytopathogenic fungi strains that exhibit resistance to commonly employed active compounds in the field. Botrytis cinerea and Colletotrichum acutatum are phytopathogenic fungi that inflict substantial economic losses within agriculture and food due to their high impacts on crops both pre- and post-harvest. Furthermore, the emergence of fungal strains that are resistant to commercial fungicides has exacerbated this problem. To explore more environmentally sustainable alternatives for the control of these pathogens, an investigation into the endophytic bacteria associated with ginger (Zingiber officinale Rosc.) was conducted. The primary focus of this study involved evaluating their inhibitory efficacy against the fungi and assessing their potential for promoting plant growth. The endophytic bacteria genera Lelliottia, Lysinibacillus, Kocuria, Agrococcus, Acinetobacter, Agrobacterium, Zymobacter, and Mycolicibacterium were identified. All isolates showed remarkable in vitro antagonistic ability against B. cinerea (>94%) and C. acutatum (>74%). Notably, the Lelliottia amnigena J29 strain exhibited a notable proficiency in producing extracellular enzymes and indole compounds (IAA), solubilizing phosphate and potassium, and forming biofilm. Furthermore, the Lysinibacillus capsici J26, Agrococcus citreus J28, and Mycolicibacterium sp. J5 strains displayed the capacity for atmospheric nitrogen fixation and siderophore production. These findings underscore the agricultural and biotechnological potential of endophytic bacteria derived from ginger plants and suggest the feasibility of developing alternative approaches to manage these two phytopathogenic fungi.

Endophytic Bacteria Bacillus subtilis, Isolated from Zea mays, as Potential Biocontrol Agent against Botrytis cinerea.

Plant diseases are one of the main factors responsible for food loss in the world, and 20-40% of such loss is caused by pathogenic infections. Botrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It is responsible for incalculable economic losses due to the large number of host plants affected. Today, B. cinerea is controlled mainly by synthetic fungicides whose frequent application increases risk of resistance, thus making them unsustainable in terms of the environment and human health. In the search for new alternatives for the biocontrol of this pathogen, the use of endophytic microorganisms and their metabolites has gained momentum in recent years. In this work, we isolated endophytic bacteria from Zea mays cultivated in Colombia. Several strains of Bacillus subtilis, isolated and characterized in this work, exhibited growth inhibition against B. cinerea of more than 40% in in vitro cultures. These strains were characterized by studying several of their biochemical properties, such as production of lipopeptides, potassium solubilization, proteolytic and amylolytic capacity, production of siderophores, biofilm assays, and so on. We also analyzed: (i) its capacity to promote maize growth (Zea mays) in vivo, and (ii) its capacity to biocontrol B. cinerea during in vivo infection in plants (Phaseolus vulgaris).

Beach litter distribution in Admiralty Bay, King George Island, Antarctica.

In the Antarctic Peninsula, most important activities are touristic visits, from the second half of the 20th Century, and scientific investigation linked to 75 research stations. Beach litter content/abundance was investigated at 17 beaches in Admiralty Bay (King George Island, Antarctica) and the type of plastic material was determined by Raman spectroscopy. An average value of 0.16 items m-1 was observed. Wood items consisted of processed wood fragments representing 47.27% of the total. Foam represented 21%, hard plastic pieces 9.68% (consisting of polyvinyl chloride or high density polyethylene), metal 3.37%, rubber fragments 2.81%, foamed plastic pieces 2.66% (composed by polystyrene), the rest of categories representing less than 2% of the total. Wood debris and metal are essentially remnant objects of ancient whaling activities and research expeditions, polyurethane and expanded polystyrene materials have different origins and hard plastic, rubber, paper/cardboard and paint fragments seem mostly linked to present research activities.

Resistencia antibiótica: el papel del hombre, los animales y el medio ambiente / Antibiotic resistance: the role of man, animals and the environment

RESUMEN Los microorganismos, especialmente las bacterias, están distribuidos por todo el mundo, desde el suelo, los mares y los ríos hasta el sistema digestivo de los animales y los seres humanos; por lo tanto, las bacterias mantienen una interacción constante con los compuestos utilizados por los seres humanos y los animales como los antibióticos, y con otros microorganismos que pueden ser de la misma especie o de diferentes géneros taxonómicos; esta interacción podría dar lugar a una presión selectiva sobre las bacterias en el medio ambiente y promover el intercambio de material genético, lo que llevaría a una propagación global de la resistencia a los antibióticos y a una afectación mundial de la salud. En este contexto, esta revisión tiene por objeto ofrecer una visión general del papel de los seres humanos, los animales y el medio ambiente en la resistencia bacteriana, con énfasis en los procesos en el suelo y los medios acuáticos y los efectos sobre la salud humana.

ABSTRACT Microorganisms, especially bacteria, are distributed throughout the world, from the soil, seas and rivers to the digestive system of animals and humans. Therefore, the bacteria maintain a constant interaction with compounds used by humans and animals, such as antibiotics, and with other microorganisms that may be of the same species or of different taxonomic genera. In addition, this interaction could lead to selective pressure on bacteria in the environment and promote the exchange of genetic material, which would allow to a global spread of antibiotic resistance and thus a worldwide affectation on health. In this context, the present review aims to provide an overview of the role of humans, animals and the environment in bacterial resistance, with emphasis on soil and aquatic processes and effects on human health.

Botrydial confers Botrytis cinerea the ability to antagonize soil and phyllospheric bacteria.

The role of the sesquiterpene botrydial in the interaction of the phytopathogenic fungus Botrytis cinerea and plant-associated bacteria was analyzed. From a collection of soil and phyllospheric bacteria, nine strains sensitive to growth-inhibition by B. cinerea were identified. B. cinerea mutants unable to produce botrydial caused no bacterial inhibition, thus demonstrating the inhibitory role of botrydial. A taxonomic analysis showed that these bacteria corresponded to different Bacillus species (six strains), Pseudomonas yamanorum (two strains) and Erwinia aphidicola (one strain). Inoculation of WT and botrydial non-producing mutants of B. cinerea along with Bacillusamyloliquefaciens strain MEP218 in soil demonstrated that both microorganisms exert reciprocal inhibitory effects; the inhibition caused by B. cinerea being dependent on botrydial production. Moreover, botrydial production was modulated by the presence of B. amyloliquefaciens MEP218 in confrontation assays in vitro. Purified botrydial in turn, inhibited growth of Bacillus strains in vitro and cyclic lipopeptide (surfactin) production by B. amyloliquefaciens MEP218. As a whole, results demonstrate that botrydial confers B. cinerea the ability to inhibit potential biocontrol bacteria of the genus Bacillus. We propose that resistance to botrydial could be used as an additional criterion for the selection of biocontrol agents of plant diseases caused by B. cinerea.

Microbiological water quality and sources of contamination along the coast of the Department of Atlántico (Caribbean Sea of Colombia). Preliminary results.

Microbiological sea water quality is a public health problem that has serious repercussions in the tourism and economy of Colombia. This study determines the concentrations of Escherichia coli, Enterococcus faecalis and Clostridium perfringens at eleven beach water points and seven streams along the coast of the Department of Atlántico, Colombia. In seawater, total E. coli, E. faecalis and C. perfringens concentrations were found between 16 and 572 cfu/100 mL, 7-450 cfu/100 ml and 2-125 cfu/100 ml, respectively. The highest counts were observed mainly on urbanised beaches and in correspondence with streams whose waters had a high concentration of faecal origin microorganisms, which represent a serious health risk factor for bathers. Relevant efforts have to be addressed to improve the microbiological quality of these beaches by the establishment of efficient wastewater management programs aimed at enhancing the efficiency of the local treatment plant and the control of illegal sewage pouring onto the coast.

Molecular detection of Salmonella spp., Listeria spp. and Brucella spp. in fresh artisanal cheese marketed in the city of Barranquilla: A pilot study

Introduction: Each year approximately 3 million people die as the result of foodborne diseases. The fresh artisan (handmade) cheese produced and distributed in the Colombian Caribbean region is a native product from the departments of Córdoba, Sucre, Bolívar, Atlántico, Magdalena, Cesar, and La Guajira. Its mass consumption increases the risk of infection with Salmonella spp., Listeria spp., and Brucella spp., as it is made with a very rustic technology, with unpasteurized cow milk, without standardized and hygienic procedures and its storage is inadequate. Objective: To detect the presence of Salmonella spp., Listeria spp., and Brucella spp. in samples of fresh artisan cheese from the Colombian Caribbean region. Materials and methods: Twenty-seven samples of cheese from five departments of the Caribbean Region (Atlántico (n=6), Bolívar (n=2), Córdoba (n=1), Magdalena (n=16), and Sucre (n=2)) were analyzed by real-time polymerase chain reaction (qPCR). Seventeen of the samples corresponded to soft cheese, five to semi-hard cheese and five to hard cheese. Results: In 62.9% (17/27) of the samples we detected Salmonella spp., in 70.4% (19/27), Listeria spp., and in 22.2% (6/27), Brucella spp., mainly from the department of Magdalena. In 62.5% (10/16) of the samples we detected Salmonella spp. and Listeria spp. while in the department of Atlántico, 50% (3/6) of the samples corresponded to Brucella spp. Conclusion: The results confirmed the presence of these microorganisms in all the samples of soft cheese from the Colombian Caribbean region.

Detección molecular de Salmonella spp., Listeria spp. y Brucella spp. en queso artesanal fresco comercializado en Barranquilla: un estudio piloto / Molecular detection of Salmonella spp., Listeria spp. and Brucella spp. in fresh artisanal cheese marketed in the city of Barranquilla: A pilot study

Introducción. Cada año mueren, aproximadamente, tres millones de personas como consecuencia de las enfermedades transmitidas por alimentos. El queso artesanal fresco que se produce y distribuye en la región Caribe colombiana es un producto autóctono de los departamentos de Córdoba, Sucre, Bolívar, Atlántico, Magdalena, Cesar y La Guajira. Su consumo masivo aumenta el riesgo de infección con salmonelosis, listeriosis y brucelosis debido a que es elaborado con una tecnología muy rústica, con leche de vaca no pasteurizada, sin procedimientos estandarizados e higiénicos, y a que su almacenamiento no es adecuado. Objetivo. Detectar la presencia de Salmonella spp., Listeria spp. y Brucella spp. en muestras de queso artesanal costeño fresco procedente de los departamentos de la región Caribe colombiana. Materiales y métodos. Mediante reacción en cadena de la polimerasa en tiempo real (qPCR), se analizaron 27 muestras de queso proveniente de cinco departamentos de la región Caribe: Atlántico (n=6), Bolívar (n=2), Córdoba (n=1), Magdalena (n=16) y Sucre (n=2). Del total de las muestras, 17 eran de queso blando, cinco de queso semiduro y cinco de queso duro. Resultados. En el 62,9 % de las muestras se detectó Salmonella spp. (17/27), en el 70,4 %, Listeria spp. (19/27), y en el 22,2 %, Brucella spp. (6/27). Las muestras provenían principalmente del departamento del Magdalena y, en 62,5 % (10/16) de ellas, se encontró Salmonella spp. y Listeria spp., en tanto que en el 50 % (3/6) de las muestras del departamento del Atlántico se detectó Brucella spp. Conclusión. Los resultados evidenciaron la presencia de estos microorganismos en todas las muestras de queso costeño blando.

Introduction: Each year approximately 3 million people die as the result of foodborne diseases. The fresh artisan (handmade) cheese produced and distributed in the Colombian Caribbean region is a native product from the departments of Córdoba, Sucre, Bolívar, Atlántico, Magdalena, Cesar, and La Guajira. Its mass consumption increases the risk of infection with Salmonella spp., Listeria spp., and Brucella spp., as it is made with a very rustic technology, with unpasteurized cow milk, without standardized and hygienic procedures and its storage is inadequate. Objective: To detect the presence of Salmonella spp., Listeria spp., and Brucella spp. in samples of fresh artisan cheese from the Colombian Caribbean region. Materials and methods: Twenty-seven samples of cheese from five departments of the Caribbean Region (Atlántico (n=6), Bolívar (n=2), Córdoba (n=1), Magdalena (n=16), and Sucre (n=2)) were analyzed by real-time polymerase chain reaction (qPCR). Seventeen of the samples corresponded to soft cheese, five to semi-hard cheese and five to hard cheese. Results: In 62.9% (17/27) of the samples we detected Salmonella spp., in 70.4% (19/27), Listeria spp., and in 22.2% (6/27), Brucella spp., mainly from the department of Magdalena. In 62.5% (10/16) of the samples we detected Salmonella spp. and Listeria spp. while in the department of Atlántico, 50% (3/6) of the samples corresponded to Brucella spp. Conclusion: The results confirmed the presence of these microorganisms in all the samples of soft cheese from the Colombian Caribbean region.