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Food Chemistry Oct 2024The influence of four microbial biostimulants containing various strains of Bacillus subtilis and/or Paenibacillus sp. on the quality of raspberries cv. Delniwa, Poemat,...
The influence of four microbial biostimulants containing various strains of Bacillus subtilis and/or Paenibacillus sp. on the quality of raspberries cv. Delniwa, Poemat, and Enrosadira cultivated in two consecutive seasons was investigated. The biostimulants influenced the antioxidant level, antioxidant capacity, phenolic acids and flavonoids profiles, enzymatic activity, and the degree of methylation and acetylation of the pectin in the raspberry fruits. The biostimulants had the greatest effect on the antioxidant content (16% - 20% increase) and capacity in the Delniwa raspberry fruits from the first season. A positive correlation was found between the activity of the β-galactosidase enzyme and ferric reducing power. In the second season, a decrease in the activity of pectin esterase and α-L-arabinofuranosidase and an increase in the degree of methylation of pectin were noted. Our results suggest that the changes in raspberry quality were related to the type of biostimulant applied.
Topics: Antioxidants; Rubus; Fruit; Bacillus subtilis; Paenibacillus; Pectins; Carboxylic Ester Hydrolases
PubMed: 38795624
DOI: 10.1016/j.foodchem.2024.139746 -
Plants (Basel, Switzerland) May 2024Wheat stripe rust is globally one of the most important diseases affecting wheat. There is an urgent need to develop environmentally safe and durable biological control...
Wheat stripe rust is globally one of the most important diseases affecting wheat. There is an urgent need to develop environmentally safe and durable biological control options to supplement the control that is achieved with breeding and fungicides. In this study, endophytic bacteria were isolated from healthy wheat through the tissue separation method. Antagonistic endophytic bacteria were screened based on the control effect of urediniospore germination and wheat stripe rust (WSR). The taxonomic status of antagonistic strains was determined based on morphological, physiological, and biochemical characteristics and molecular biological identification (16S rDNA and gene sequence analysis). Finally, the potential growth-promoting effect of different concentrations of antagonists on wheat seedlings and the biological control effect of WSR were studied. A total of 136 strains of endophytic bacteria belonging to 38 genera were isolated. was the most common bacterial genus, with 29 isolates (21%). The biological control effect of different isolates was assessed using an urediniospore germination assay. The isolate XD29-G1 of had the best performance, with 85% inhibition of spore germination during primary screening. In the deep screening, the control effect of XD29-G1 on wheat stripe rust was 60%. The antagonist XD29-G1 promoted the germination of wheat seeds and the growth of wheat seedlings at a solution dilution of 10 cfu/mL. The pot experiment results showed that different dilution concentrations of the strain had different levels of antibacterial activity against WSR, with the concentration of 10 cfu/mL having the best control effect and a control efficiency of 61.19%. XD29-G1 has better biological control potential against wheat stripe rust.
PubMed: 38794437
DOI: 10.3390/plants13101366 -
Insects May 2024Honeybee diseases are one of the most significant and most common causes of honeybee colonies' weakness and death. An early diagnosis of subclinical infections is...
Honeybee diseases are one of the most significant and most common causes of honeybee colonies' weakness and death. An early diagnosis of subclinical infections is necessary to implement precautionary and control measures. Sampling debris from hive bottom boards is simple, non-invasive, and cheap. In this study, we collected winter debris samples in apiaries located in the continental part of Croatia. We used molecular methods, PCR and qPCR, for the first time to analyze those samples. Laboratory results were compared with the health condition and strength of honeybee colonies at an apiary in spring. Our study successfully identified the presence and quantity of various pathogens, including the presence of spp. ( spp.), quintefied , Acute Bee Paralysis Virus (ABPV), Black Queen Cell Virus (BQCV), Deformed Wing Virus (DWV), and Sacbrood Virus (SBV). However, our analysis did not detect , , , and . Samples of winter debris were also examined for the presence and quantification of the mites, and their natural mite fall was observed in spring. Honeybee colonies were simultaneously infected by an average of four to six pathogens. Some observed honeybee colonies developed characteristic symptoms, while others did not survive the winter.
PubMed: 38786906
DOI: 10.3390/insects15050350 -
PloS One 2024Plant growth-promoting rhizobacteria (PGPR) applications have emerged as an ideal substitute for synthetic chemicals by their ability to improve plant nutrition and...
Plant growth-promoting rhizobacteria (PGPR) applications have emerged as an ideal substitute for synthetic chemicals by their ability to improve plant nutrition and resistance against pathogens. In this study, we isolated fourteen root endophytes from healthy wheat roots cultivated in Tunisia. The isolates were identified based from their 16S rRNA gene sequences. They belonged to Bacillota and Pseudomonadota taxa. Fourteen strains were tested for their growth-promoting and defense-eliciting potentials on durum wheat under greenhouse conditions, and for their in vitro biocontrol power against Fusarium culmorum, an ascomycete responsible for seedling blight, foot and root rot, and head blight diseases of wheat. We found that all the strains improved shoot and/or root biomass accumulation, with Bacillus mojavensis, Paenibacillus peoriae and Variovorax paradoxus showing the strongest promoting effects. These physiological effects were correlated with the plant growth-promoting traits of the bacterial endophytes, which produced indole-related compounds, ammonia, and hydrogen cyanide (HCN), and solubilized phosphate and zinc. Likewise, plant defense accumulations were modulated lastingly and systematically in roots and leaves by all the strains. Testing in vitro antagonism against F. culmorum revealed an inhibition activity exceeding 40% for five strains: Bacillus cereus, Paenibacillus peoriae, Paenibacillus polymyxa, Pantoae agglomerans, and Pseudomonas aeruginosa. These strains exhibited significant inhibitory effects on F. culmorum mycelia growth, sporulation, and/or macroconidia germination. P. peoriae performed best, with total inhibition of sporulation and macroconidia germination. These finding highlight the effectiveness of root bacterial endophytes in promoting plant growth and resistance, and in controlling phytopathogens such as F. culmorum. This is the first report identifying 14 bacterial candidates as potential agents for the control of F. culmorum, of which Paenibacillus peoriae and/or its intracellular metabolites have potential for development as biopesticides.
Topics: Fusarium; Triticum; Endophytes; Biological Control Agents; Plant Diseases; Plant Roots; Tunisia; Bacteria; RNA, Ribosomal, 16S
PubMed: 38758965
DOI: 10.1371/journal.pone.0300791 -
Microbiology Resource Announcements Jun 2024The genome of a spore-forming bacterium isolated from the spacecraft assembly facility of the Phoenix mission, was generated via hybrid assembly by merging short and...
The genome of a spore-forming bacterium isolated from the spacecraft assembly facility of the Phoenix mission, was generated via hybrid assembly by merging short and long reads. Examining this genome may shed light on strategies to minimize the risk of contaminating extraterrestrial environments with Earth-based microorganisms.
PubMed: 38742883
DOI: 10.1128/mra.01265-23 -
Current Microbiology May 2024As a primary nutrient in agricultural soils, phosphorus plays a crucial but growth-limiting role for plants due to its complex interactions with various soil elements....
As a primary nutrient in agricultural soils, phosphorus plays a crucial but growth-limiting role for plants due to its complex interactions with various soil elements. This often results in excessive phosphorus fertilizer application, posing concerns for the environment. Agri-research has therefore shifted focus to increase fertilizer-use efficiency and minimize environmental impact by leveraging plant growth-promoting rhizobacteria. This study aimed to evaluate the in-field incremental effect of inorganic phosphate concentration (up to 50 kg/ha/P) on the ability of two rhizobacterial isolates, Lysinibacillus sphaericus (T19), Paenibacillus alvei (T29), from the previous Breedt et al. (Ann Appl Biol 171:229-236, 2017) study on maize in enhancing the yield of commercially grown Duzi® cultivar wheat. Results obtained from three seasons of field trials revealed a significant relationship between soil phosphate concentration and the isolates' effectiveness in improving wheat yield. Rhizospheric samples collected at flowering during the third season, specifically to assess phosphatase enzyme activity at the different soil phosphate levels, demonstrated a significant decrease in soil phosphatase activity when the phosphorus rate reached 75% for both isolates. Furthermore, in vitro assessments of inorganic phosphate solubilization by both isolates at five increments of tricalcium phosphate-amended Pikovskaya media found that only isolate T19 was capable of solubilizing tricalcium at concentrations exceeding 3 mg/ml. The current study demonstrates the substantial influence of inorganic phosphate on the performance of individual rhizobacterial isolates, highlighting that this is an essential consideration when optimizing these isolates to increase wheat yield in commercial cultivation.
Topics: Triticum; Phosphates; Soil Microbiology; Soil; Rhizosphere; Fertilizers; Paenibacillus; Phosphorus
PubMed: 38734822
DOI: 10.1007/s00284-024-03685-x -
Saudi Journal of Biological Sciences Jun 2024American foulbrood (AFB) is a harmful honeybee disease primarily caused by . The study aims to isolate and identify the AFB causative agent and their specific phages...
American foulbrood (AFB) is a harmful honeybee disease primarily caused by . The study aims to isolate and identify the AFB causative agent and their specific phages to use as a new biological method for AFB disease control. Eight apiaries were inspected for AFB infections. Symptoms of diseased brood comb, were odd brood cells with soft brown decayed brood amongst healthy brood, were identified in the field and demonstrated the prevalence of AFB in every apiary. Three isolates were identified using traditional techniques using a 452-bp PCR amplicon specific to the bacterial 16SrRNA gene and was compared between isolates. Additionally, specific phages of strains were applied to examine their efficiency in reducing the infection rate under the apiary condition. The infection rate was reduced to approximately 94.6 to 100 % through the application of a phage mixture, as opposed to 20 to 85.7 % when each phage was administered individually or 78.6 to 88.9 % when antibiotic treatment was implemented. Histological studies on phage-treated bee larvae revealed some cells regaining normal shape, with prominent nuclei and microvilli. The gastrointestinal tract showed normal longitudinal and circular muscles, unlike bee larvae treated with bacterial strains with abnormal and destroyed tissues, as shown by the basement membrane surrounding the mid-gut epithelium. Phage techniques exhibited promise in resolving the issue of AFB in honeybees due to their ease of application, comparatively lower cost, and practicality for beekeepers in terms of laboratory preparation.
PubMed: 38706719
DOI: 10.1016/j.sjbs.2024.104002 -
Journal of Food Protection Jul 2024Beverage innovation is a growing trend with a reliance on comanufacturing relationships to launch products quickly. A recent comanufacturing relationship is the...
Beverage innovation is a growing trend with a reliance on comanufacturing relationships to launch products quickly. A recent comanufacturing relationship is the utilization of dairy processing facilities to process plant-based beverages using high-temperature short-time (HTST) pasteurization. While the shelflife of HTST bovine milk is well established at 21 days, retailers are expecting new refrigerated beverages to achieve a 60-day shelflife. Little is known about the microbial stability of these new beverages, particularly those with complex formulations. Our objective was to identify bacterial taxa leading to the spoilage of four coconut-based creamers and their potential sources (raw ingredients or packaging). We used a multifaceted approach including plate counting and 16S rRNA metabarcoding to monitor microbial growth in products throughout shelflife (60 d, 4 °C), and cold enrichment (7 °C, 11 d) of ingredients and packaging. Nearly all product units (25/26) had elevated microbial loads (>4.3 log CFU/mL) prior to the 60-d target, with early spoilage detected at 21 d. Key spoilage taxa included Pseudomonas, Streptococcus, Aerococcus, Paenibacillus, Sphingomonas, and Oceanobacillus. Pseudomonas were responsible for "early" product spoilage (21-32 d), whereas Oceanobacillus were important in products with very "late" spoilage (60-62 d). All key spoilage taxa were identified in cold enrichments of multiple units of waxboard cartons. Paenibacillus was the dominant bacterium in 47% (10/21) of product units. In addition to carton samples, Paenibacillus was also identified in one raw ingredient (mushroom extract). Metabarcoding identified Listeria sensu stricto as a dominant taxon in three individual product units from three distinct production lots. Listeria was also found in 31% (5/16) of cold enrichments of individual cartons. Taxa responsible for spoilage of plant-based beverages were identified as well as demonstrating packaging as an important contamination source.
Topics: Cocos; Bacteria; Food Microbiology; Food Contamination; Colony Count, Microbial; Animals; Beverages; Cattle; Food Packaging
PubMed: 38692353
DOI: 10.1016/j.jfp.2024.100284 -
Microbiology Resource Announcements Jun 2024Streptomycin thallous acetate actidione medium is typically used to isolate bacteria from food. Using this medium, three bacterial strains were isolated from the...
Streptomycin thallous acetate actidione medium is typically used to isolate bacteria from food. Using this medium, three bacterial strains were isolated from the environment. Genomic sequences demonstrated that these bacteria are of the genera and and are of biotechnological interest.
PubMed: 38682917
DOI: 10.1128/mra.00199-24 -
Waste Management (New York, N.Y.) Jun 2024Carbon monoxide (CO) formation has been observed during composting of various fractions of organic waste. It was reported that this production can be biotic, associated...
Carbon monoxide (CO) formation has been observed during composting of various fractions of organic waste. It was reported that this production can be biotic, associated with the activity of microorganisms. However, there are no sources considering the microbial communities producing CO production in compost. This preliminary research aimed to isolate and identify microorganisms potentially responsible for the CO production in compost collected from two areas of the biowaste pile: with low (118 ppm) and high CO concentration (785 ppm). Study proved that all isolates were bacterial strains with the majority of rod-shaped Gram-positive bacteria. Both places can be inhabited by the same bacterial strains, e.g. Bacillus licheniformis and Paenibacillus lactis. The most common were Bacillus (B. licheniformis, B. haynesii, B. paralicheniformis, and B. thermolactis). After incubation of isolates in sealed bioreactors for 4 days, the highest CO levels in the headspace were recorded for B. paralicheniformis (>1000 ppm), B. licheniformis (>800 ppm), and G. thermodenitrificans (∼600 ppm). High CO concentrations were accompanied by low O (<6%) and high CO levels (>8%). It is recommended to analyze the expression of the gene encoding CODH to confirm or exclude the ability of the identified strains to convert CO to CO.
Topics: Carbon Monoxide; Composting; Soil Microbiology; Bacillus; Bioreactors; Bacteria
PubMed: 38677142
DOI: 10.1016/j.wasman.2024.04.044