Native Strains Research Articles

Pathogenicity of native strains of Bacillus thuringiensis, Beauveria bassiana and Metarhizium rileyi as entomopathogens against the polyphagous borer, Conogethes punctiferalis (Guenée) (Crambidae: Lepidoptera)

BackgroundThe shoot and fruit borer, Conogethes punctiferalis (Guenée) (Crambidae: Lepidoptera), is a significant pest causing substantial economic losses across various crops. The need for alternative control methods has prompted the exploration of biological control using entomopathogenic fungi and bacteria. In this study, the pathogenicity of Beauveria bassiana, Metarhizium (Nomuraea) rileyi and Bacillus thuringiensis (Bt) against C. punctiferalis larvae and pupae was assessed through laboratory bioassays.ResultsVarious concentrations of B. bassiana and M. rileyi spores, i.e. 1 × 102, 1 × 104, 1 × 106, 1 × 107 and 1 × 108 spores/ml, were tested alongside controls. Additionally, five strains of Bt (IIOR Bt-145, Bt-154, Bt-171, Bt-172 and Bt-127) were evaluated at concentrations of 0.5, 1.0, 1.5, 2.0 and 2.5 mg/ml. The LC50 values for B. bassiana and M. rileyi were 7.9 × 105 spores/ml and 8.7 × 104 spores/ml, respectively, after 4 and 6 days of post-treatment using the spray method. In the larval dip method, the LC50 values were 4.8 × 103 spores/ml for B. bassiana and 2.0 × 104 spores/ml for M. rileyi after 5 and 6 days of treatment, respectively. For pupae, the LC50 values were 1.2 × 106 spores/ml for B. bassiana and 4.3 × 104 spores/ml for M. rileyi after 4 and 7 days of treatment, respectively. Similarly, the five strains of Bt were effective against C. punctiferalis. However, Bt-154 demonstrated the highest efficacy, with LC50 values of 0.66 mg/ml in the spray method and 0.79 mg/ml in the larval dip method after 5 days of post-treatment.ConclusionThe potential of entomopathogenic isolates as biocontrol agents against C. punctiferalis provided a promising alternative to synthetic insecticides in pest management. The efficacy of B. bassiana, M. rileyi and Bt strains suggests their suitability for integrated pest management strategies, potentially reducing reliance on chemical pesticides and minimizing the environmental impacts. Further field studies are warranted to validate the efficacy and practicality of these biocontrol agents in real-world agricultural settings.

Development of a microbial dewaxing agent using three spore forming bacteria

Microbial enhanced oil recovery (MEOR) is a cost effective and efficient method for recovering residual oil. However, the presence of wax (paraffin) in residual oil can substantially reduce the efficiency of MEOR. Therefore, microbial dewaxing is a critical process in MEOR. In this study, a bacterial dewaxing agent of three spore-forming bacteria was developed. Among these bacteria, Bacillus subtilis GZ6 produced the biosurfactant surfactin. Replacing the promoter of the surfactin synthase gene cluster (srfA), increased the titer of surfactin in this strain from 0.33 g/L to 2.32 g/L. The genetically modified strain produced oil spreading rings with diameters increasing from 3.5 ± 0.1 to 4.1 ± 0.2 cm. The LadA F10L/N133R mutant was created by engineering an alkane monooxygenase (LadA) using site-directed mutagenesis in the Escherichia coli host. Compared to the wild-type enzyme, the resulting mutant exhibited an 11.7-fold increase in catalytic efficiency toward the substrate octadecane. When the mutant (pIMPpladA2mu) was expressed in Geobacillus stearothermophilus GZ178 cells, it exhibited a 2.0-fold increase in octadecane-degrading activity. Cultures of the two modified strains (B. subtilis GZ6 (pg3srfA) and G. stearothermophilus GZ178 (pIMPpladA2mu)) were mixed with the culture of Geobacillus thermodenitrificans GZ156 at a ratio of 5:80:15. The resulting composition increased the rate of wax removal by 35% compared to the composition composed of three native strains. This study successfully developed a multi-strain bacterial agent with enhanced oil wax removal capabilities by genetically engineering two bacterial strains.

Protective role of native root-associated bacterial consortium against root-knot nematode infection in susceptible plants

Root-knot nematodes (RKNs) are a global menace to agricultural crop production. The role of root-associated microbes (RAMs) in plant protection against RKN infection remains unclear. Here we observe that cucumber (highly susceptible to Meloidogyne incognita) exhibits a consistently lower susceptibility to M. incognita in the presence of native RAMs in three distinct soils. Nematode infection alters the assembly of bacterial RAMs along the life cycle of M. incognita. Particularly, the loss of bacterial diversity of RAMs exacerbates plant susceptibility to M. incognita. A diverse range of native bacterial strains isolated from M. incognita-infected roots has nematode-antagonistic activity. Increasing the number of native bacterial strains causes decreasing nematode infection, which is lowest when six or more bacterial strains are present. Multiple simplified synthetic communities consisting of six bacterial strains show pronounced inhibitory effects on M. incognita infection in plants. These inhibitory effects are underpinned via multiple mechanisms including direct inhibition of infection, secretion of anti-nematode substances, and regulation of plant defense responses. This study highlights the role of native bacterial RAMs in plant resistance against RKNs and provides a useful insight into the development of a sustainable way to protect susceptible plants.

Production of Bio-Diesel from Dairy Waste Scum

Abstract-Dairy factory waste scums are increasingly being considered a valuable resource. However, these wastes may also contain contaminants, natural or artificial, that may adversely affect the land or water to which they are discharged. The study investigates the potential of using dairy waste scum as a feed stock for bio-diesel production. Present study optimized the parameters involved in the alkali catalysed Trans esterification process of dairy waste scum oil. The effects of methanol to oil ratio, temperature and amount of KOH were investigated. A study was conducted to evaluate the capability of production of biodiesel from consortium of native microalgae culture in dairy farm treated waste water. Native algal strains were isolated from dairy farm waste waters collection tank (untreated wastewater) as well as from holding tank (treated wastewater). The consortium members were selected on the basis of fluorescence response after treating with Nile red reagent. Preliminary studies of two commercial and consortium often native strains of algae showed good growth in waste waters. A consortium of native strains was found capable to remove more than 98% nutrients from treated waste water. The biomass production and lipid content of consortium cultivated in treated waste water were 153.54t ha-1 year-1 and 16.89%, respectively. 72.70% of algal lipid obtained from consortium could be converted into biodiesel. The present study found that bio- diesel from dairy waste scum is quite suitable as an alternative to petroleum diesel with recommended fuel properties as per ASTM standards. By using dairy waste scum as a feed stock for bio diesel and the environmental impact related to the disposal of dairy scum Keywords: Environment,Bio-Diesel,Dairy Waste Scum, Extraction of Lipids

Effects of Non-steroidal Anti-inflammatory Drugs (Ibuprofen and Diclofenac) and Their Mixtures on the Growth of Three Green Algae

Ibuprofen (IBU) and diclofenac (DFN) are the most widely consumed non-steroidal anti-inflammatory (NSAIDs) worldwide. Since they are not completely metabolized in the human body, the unaltered active ingredients can reach aquatic ecosystems through domestic effluents. The aim of this study was to analyse the toxic effects of IBU and DFN, individually and in mixtures, on three freshwater green algae strains, the international standard strain Raphidocelis subcapitata and two native strains, Ankistrodesmus fusiformis and Tetradesmus obliquus. Bioassays were carried out according to the 72-h algal growth inhibition test. The concentration-response curve of the mixture was compared to predicted effects based on both the concentration addition (CA) and the independent action (IA) models. The two drugs tested individually were toxic to all three algal strains, with EC50 values <100 mg L-1. According to these values, the most sensitive strain was R. subcapitata (IBU = 20 mg L-1 and DFN = 8 mg L-1). The most resistant strain was T. obliquus (IBU = 74.1 mg L-1 and DFN = 92.7 mg L-1) and the A. fusiformis strain showed intermediate sensitivity (IBU = 26.7 mg L-1 and DFN = 14.6 mg L-1). The mixtures showed a synergistic effect on R. subcapitata, an additive effect on A. fusiformis, and an antagonistic effect on T. obliquus. Neither the CA nor the IA model was appropriate for predicting the toxicity of the mixtures. In conclusion, IBU and DFN showed toxic effects on the algae growth at the concentrations tested. Individual and mixed toxicity was different according to the species. These differences could be species-specific, showing the importance of including native strains in ecotoxicological studies to evaluate the potential effects of pollutants in regional aquatic environments.

Exploring the Potential of Native Urease-Producing Bacteria of Hilly Terrain for Soil Strength Enhancement

Bio-cementation of weathered soils of hilly regions using native ureolytic bacteria is a practical approach to improve soil strength. This study aimed to isolate and characterize native urease-producing bacterial strains from different slope failure regions of Uttarakhand, India, through multi-step screening, and showcased their potential in soil improvement. A total of 80 bacterial strains were isolated from thirteen landslide-prone sites to screen for potent native urease-producing strains. Interestingly, nine native strains exhibited high calcium carbonate precipitation (158–187 mg/10 ml) and urease activity (657–3495 µM/mL) compared to Sporosarcina pasteurii (NCIM 2477), a potent bacterium commonly used for bio-cementation. These strains belonged to various genera, including Lysinibacillus sp., Sporosarcina sp., Pseudochrobactrum sp., and Cytobacillus sp. Cohesionless soil samples treated with the native strains exhibited high unconfined compressive strength values ranging from 0.1 MPa to 1 MPa, whereas those treated with S. pasteurii were 0.15 MPa. The urease-producing bacterial strains with CaCO3 precipitation activity influenced the soil strength and failure patterns. FESEM, XRD, and acid-washing tests revealed that native bacterial strains precipitated CaCO3 more than S. pasteurii strain. The study explores, for the first time, the potential of native ureolytic bacteria from different regions of Uttarakhand, India, for soil strength enhancement.

CAN THE RETURN TO THE NATURAL CONDITIONS OF IN VIVO PARASITIZATION INCREASE THE INFECTIVITY PERFORMANCE OF EPNS?

Experiments are in progress in Apulian asparagus fields for the control of Parahypopta caestrum (Hübner) (Lepidoptera, Cossidae) with microbial control agents (MCAs), mainly entomopathogenic nematodes and fungi.Different bioassays were carried out in laboratory and field conditions to prove the efficacy of native and commercial strains of the EPNs Steinernema feltiae (Filipijev), S. carpocapsae (Rhabditida, Steinernematidae) and Heterorhanditis bacteriophora Poinar (Rhabditida, Heterorhabditidae), and EPF Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales, Cordycipitaceae). Among the field experiments, one was planned with the release of Galleria mellonella (L.) (Lepidoptera, Pyralidae) cadavers previously infected with native strains of EPN Steinernema feltiae and the comparison was carried out with a commercial strain of the same nematode species. Key Words: Parahypopta caestrum, Beauveria, Heterorhanditis, Steinernem

Seed Priming with Rhizospheric Bacillus subtilis: A Smart Strategy for Reducing Fumonisin Contamination in Pre-Harvest Maize.

Maize, one of the most important cereal crops in Bangladesh, is severely contaminated by fumonisin, a carcinogenic secondary metabolite produced by Fusarium including Fusarium proliferatum. Biocontrol with Bacillus strains is an effective approach to controlling this F. proliferatum as Bacillus has proven antagonistic properties against this fungus. Therefore, the present study aimed to determine how native Bacillus strains can reduce fumonisin in maize cultivated in Bangladesh, where BDISO76MR (Bacillus subtilis) strains showed the highest efficacy both in vitro in detached cob and in planta under field conditions. The BDISO76MR strain could reduce the fumonisin concentration in detached cob at 98.52% over untreated control, by inhibiting the conidia germination and spore formation of F. proliferatum at 61.56% and 77.01%, respectively in vitro. On the other hand, seed treatment with formulated BDISO76MR showed higher efficacy with a reduction of 97.27% fumonisin contamination compared to the in planta cob inoculation (95.45%) over untreated control. This implies that Bacillus-based formulation might be a potential approach in mitigating fumonisin contamination in maize to ensure safe food and feed.

Propagation of distinct CWD prion strains during peripheral and intracerebral challenges of gene-targeted mice

Since prion diseases result from infection and neurodegeneration of the central nervous system (CNS), experimental characterizations of prion strain properties customarily rely on the outcomes of intracerebral challenges. However, natural transmission of certain prions, including those causing chronic wasting disease (CWD) in elk and deer, depends on propagation in peripheral host compartments prior to CNS infection. Using gene-targeted GtE and GtQ mice, which accurately control cellular elk or deer PrP expression, we assessed the impact that peripheral or intracerebral exposures play on CWD prion strain propagation and resulting CNS abnormalities. Whereas oral and intraperitoneal transmissions produced identical neuropathological outcomes in GtE and GtQ mice and preserved the naturally convergent conformations of elk and deer CWD prions, intracerebral transmissions generated CNS prion strains with divergent biochemical properties in GtE and GtQ mice that were changed compared to their native counterparts. While CWD replication kinetics remained constant during iterative peripheral transmissions and brain titers reflected those found in native hosts, serial intracerebral transmissions produced 10-fold higher prion titers and accelerated incubation times. Our demonstration that peripherally and intracerebrally challenged Gt mice develop dissimilar CNS diseases which result from the propagation of distinct CWD prion strains points to the involvement of tissue-specific cofactors during strain selection in different host compartments. Since peripheral transmissions preserved the natural features of elk and deer prions, whereas intracerebral propagation produced divergent strains, our findings illustrate the importance of experimental characterizations using hosts that not only abrogate species barriers but also accurately recapitulate natural transmission routes of native strains.

Microbiological identification of some culturable native strains associated with the digestive tract in Panaque cochliodon

Objective. To characterize by microbiology the native strains associated to the intestinal tract of the species Panaque cochliodon. Materials and methods. Three adult specimens captured in the Magdalena River that were transported and sacrificed under animal welfare regulations were used. Dissection of the intestinal tract was performed, obtaining samples for microbiological isolation, using culture media, purifying the microorganisms, performing metabolic biochemical tests and API 20E (Biomeriux) tests for their identification. Results. Information on the microbial population structure was obtained, reporting the phylum Proteobacteria with the species: Pantoea sp, Erwinia sp, Providencia stuarti, Providencia alcalifaciens, Serratia ficaria, Citrobacter koseri and the phylum Firmicutes with the species: Bacillus sphaericus, Bacillus subtilis, Bacillus thurigiensis, Bacillus mycoides, Bacillus coagulans and Bacillus circulans. Conclusion. The predominant culturable microorganisms in P. cohliodon belong to the phylum Proteobacteria and the phylum Firmicutes.

Isolation and identification of marine microalgae from Egyptian coasts as potential source of biodiesel: morphology and sequence-based screening

ABSTRACT Microalgae are a highly effective and renewable source of biodiesel that can be used as a substitute for petro-diesel in the global fuel market. In the present study, 14 water samples were collected from a variety of locations along the coastal areas of the Red Sea and the Mediterranean Sea in Egypt. These water samples, which contained microalgae, were subjected to enrichment process and standard procedures to obtain pure cultures. Based on morphological features, 27 microalgae isolates representing 12 different species were identified, with Chlorella species being the most dominant. Based on 18s rRNA gene sequencing, nine new native microalgae strains were identified, comprising four strains belonging to Chlorella species, two strains to Chlamydomonas, and one strain each of Phormidium, Nostoc, and Microcytosis species that could be appropriate for producing biodiesel. This information could be used to improve the knowledge on the composition of planktonic microalgal communities of Egypt and the target native species for biodiesel production.

Lactate-mediated mixotrophic co-cultivation of Clostridium drakei and recombinant Acetobacterium woodii for autotrophic production of volatile fatty acids

BackgroundAcetogens, a diverse group of anaerobic autotrophic bacteria, are promising whole-cell biocatalysts that fix CO2 during their growth. However, because of energetic constraints, acetogens exhibit slow growth and the product spectrum is often limited to acetate. Enabling acetogens to form more valuable products such as volatile fatty acids during autotrophic growth is imperative for cementing their place in the future carbon neutral industry. Co-cultivation of strains with different capabilities has the potential to ease the limiting energetic constraints. The lactate-mediated co-culture of an Acetobacterium woodii mutant strain, capable of lactate production, with the Clostridium drakei SL1 type strain can produce butyrate and hexanoate. In this study, the preceding co-culture is characterized by comparison of monocultures and different co-culture approaches.ResultsC. drakei grew with H2 + CO2 as main carbon and energy source and thrived when further supplemented with D-lactate. Gas phase components and lactate were consumed in a mixotrophic manner with acetate and butyrate as main products and slight accumulation of hexanoate. Formate was periodically produced and eventually consumed by C. drakei. A lactate-mediated co-culture of the A. woodii [PbgaL_ldhD_NFP] strain, engineered for autotrophic lactate production, and C. drakei produced up to 4 ± 1.7 mM hexanoate and 18.5 ± 5.8 mM butyrate, quadrupling and doubling the respective titers compared to a non-lactate-mediated co-culture. Further co-cultivation experiments revealed the possible advantage of sequential co-culture over concurrent approaches, where both strains are inoculated simultaneously. Scanning electron microscopy of the strains revealed cell-to-cell contact between the co-culture partners. Finally, a combined pathway of A. woodii [PbgaL_ldhD_NFP] and C. drakei for chain-elongation with positive ATP yield is proposed.ConclusionLactate was proven to be a well-suited intermediate to combine the high gas uptake capabilities of A. woodii with the chain-elongation potential of C. drakei. The cell-to-cell contact observed here remains to be further characterized in its nature but hints towards diffusive processes being involved in the co-culture. Furthermore, the metabolic pathways involved are still speculatory for C. drakei and do not fully explain the consumption of formate while H2 + CO2 is available. This study exemplifies the potential of combining metabolically engineered and native bacterial strains in a synthetic co-culture.

Isolation and Characterization of Plant Growth-Promoting Bacteria from the Rhizosphere of Medicinal and Aromatic Plant Minthostachys verticillata.

This study aimed to isolate and characterize Pseudomonas native strains from the rhizospheric soil of Minthostachys verticillata plants to evaluate their potential as plant growth-promoting rhizobacteria (PGPR). A total of 22 bacterial isolates were obtained and subjected to various biochemical tests, as well as assessments of plant growth-promoting traits such as phosphate solubilization, hydrogen cyanide production, biocontrol properties through antibiosis, and indole acetic production. Genotypic analysis via 16S rRNA gene sequencing and phylogenetic tree construction identified the strains, with one particular strain named SM 33 showing significant growth-promoting effects on M. verticillata seedlings. This strain, SM 33, showed high similarity to Stutzerimonas stutzeri based on 16S rRNA gene sequencing and notably increased both shoot fresh weight and root dry weight of the plants. These findings underscore the potential application of native Pseudomonas strains in enhancing plant growth and health, offering promising avenues for sustainable agricultural practices.

Delineating acetaminophen biodegradation kinetics and metabolomics using bacterial community.

Acetaminophen [N-(4-hydroxyphenyl) acetamide, APAP]is an extensively and frequently consumed over-the-counter analgesic and antiphlogistic medication. It is being regarded as an emerging pollutant due to its continuous increment in the environment instigating inimical impacts on humans and the ecosystem. Considering its wide prevalence in the environment, there is an immense need of appropriate methods for the removal of APAP. The present study indulged screening and isolation of APAP degrading bacterial strains from pharmaceuticals-contaminated sites, followed by their molecular characterization via 16SrRNA sequencing. The phylogenetic analyses assigned the isolates to the genera Pseudomonas, Bacillus, Paracoccus, Agrobacterium, Brucella, Escherichia, and Enterobacter based on genetic relatedness. The efficacy of these strains in batch cultures tested through High-performance Liquid Chromatography (HPLC) revealed Paracoccus sp. and Enterobacter sp. as the most promising bacterial isolates degrading up to 88.96 and 85.92%, respectively of 300mg L-1 of APAP within 8days of incubation. Michaelis-Menten kinetics model parameters also elucidated the high degradation potential of these isolates. The major metabolites identified through FTIR and GC-MS analyses were 4-aminophenol, hydroquinone, and 3-hydroxy-2,4-hexadienedioic. Therefore, the outcomes of this comprehensive investigation will be of paramount significance in formulating strategies for the bioremediation of acetaminophen-contaminated sites through a natural augmentation process via native bacterial strains.

Identification of Metabolites in Muscles of Lueyang Black-Bone Chickens: A Comparative Analysis of Caged and Cage-Free Rearing Modes Using Untargeted Metabolomic Techniques.

The Lueyang black-bone chicken is a specific native chicken strain in China. This study aimed to investigate the effects of different rearing systems on the meat quality of Lueyang black-bone chickens. Six hundred Lueyang black-bone hens were randomly divided into two groups at 7 weeks of age and raised in cage and cage-free systems for 20 weeks. The carcass yield, meat quality, and total metabolites were measured in both the leg and breast muscles. By comparison, the carcass yield of hens in the cage-free (CF) group (1.26 ± 0.09 kg) was significantly lower than that in the caged rearing (CR) group (1.52 ± 0.15 kg). However, the shear force of leg muscles in the CF group (27.98 ± 2.43 N) was significantly greater than that in the CR group (24.15 ± 1.93 N). In addition, six samples from each group were randomly selected and their metabolites were detected by the non-targeted metabolomics technique. Among these metabolites, 408 and 354 significantly differentially abundant metabolites were identified in breast and leg muscles, which were mainly involved in glycerophospholipid metabolism, unsaturated fatty acid biosynthesis, arginine and proline metabolism, and nucleotide metabolism. We found that the levels of 19 phospholipids, mainly phosphatidylcholines and lysophosphatidylcholines, were significantly greater in the CF group than in the CR group. Additionally, the contents of eight unsaturated fatty acids, linoleic acid, and linolenic acid were dramatically greater in the CF group than in the caged group. The accumulation of 4-hydroxy-proline, glutamate, and adenosine 3'-monophosphate (AMP) was enhanced in the CF group. Moreover, many more volatile organic compounds were identified in the muscles of the cage-free group, enhancing the flavor of the chicken meat. In conclusion, the cage-free rearing mode facilitates the accumulation of nutrients and flavor substances in the chicken meat and is a better rearing system for Lueyang black-bone chickens.

Isolation and characterization of a native strain of the entomopathogenic fungus Beauveria bassiana for the control of the palm weevil Dynamis borassi (Coleoptera: Curculionidae) in the neotropics

This study aimed to isolate and characterize a native strain of Beauveria bassiana, coded as Bv065, showcasing its potential as a biological control agent targeting the palm weevil Dynamis borassi. Originating from a naturally infected D. borassi specimen collected in southwestern Colombia, the fungus underwent molecular identification and was identified as B. bassiana, exhibiting high sequence similarity with known reference strains. The physiological characterization revealed that Bv065 thrived within a temperature range of 25 to 30 °C and a pH range of 6 to 9. Moreover, the key carbon sources that allow optimal growth of the strain were identified through metabolic profiling, including sucrose, D-mannose, and γ-amino-butyric acid. These findings offer strategic insights for scalability and formulation methodologies. Additionally, enzymatic analyses unveiled robust protease activity within Bv065, crucial for catalysing insect cuticle degradation and facilitating host penetration, thus accentuating its entomopathogenic potential. Subsequent evaluations exposed Bv065’s pathogenicity against D. borassi, causing significant mortality within nine days of exposure, albeit exhibiting limited effectiveness against Rhynchophorus palmarum. This study underscores the importance of understanding optimal growth conditions and metabolic preferences of B. bassiana strains for developing effective biopesticides. The findings suggest Bv065 as a promising candidate for integrated pest management strategies in neotropical regions, particularly for controlling palm weevil infestations in coconut and peach palm cultivation. Future research avenues include refining mass production methodologies, formulating novel delivery systems, and conducting comprehensive field efficacy trials to unlock the full potential of Bv065 in fostering sustainable pest management practices. Overall, this study contributes to the growing body of knowledge on entomopathogenic fungi and their pivotal role in biological control, offering nuanced perspectives on eco-friendly alternatives to conventional insecticidal interventions.

Enhancing drought stress tolerance and growth promotion in chiltepin pepper (Capsicum annuum var. glabriusculum) through native Bacillus spp.

The drought can cause a decrease in food production and loss of biodiversity. In northern Mexico, an arid region, the chiltepin grows as a semi-domesticated crop that has been affected in its productivity and yield. An alternative to mitigate the effect of drought and aid in its conservation could be using Plant Growth-Promoting Bacteria (PGPB). The present study evaluated the capacity of native Bacillus spp., isolated from arid soils, as PGPBs and drought stress tolerance inducers in chiltepin under controlled conditions. Chiltepin seeds and seedlings were inoculated with native strains of Bacillus spp. isolated from arid soils, evaluating germination, vegetative, and drought stress tolerance parameters. The PGPBs improved vegetative parameters such as height, stem diameter, root length, and slenderness index in vitro. B. cereus (Bc25-7) improved in vitro survival of stressed seedlings by 68% at −1.02 MPa. Under greenhouse conditions, seedlings treated with PGPBs exhibited increases in root length (9.6%), stem diameter (13.68%), leaf fresh weight (69.87%), and chlorophyll content (38.15%). Bc25-7 alleviated severe water stress symptoms (7 days of water retention stress), and isolates B. thuringiensis (Bt24-4) and B. cereus (Bc25-7, and Bc30-2) increased Relative Water Content (RWC) by 51%. Additionally, the treated seeds showed improved germination parameters with a 46.42% increase in Germination Rate (GR). These findings suggest that using PGPBs could be an alternative to mitigate the effect of drought on chiltepin.

Isolation and Molecular Characterization of Polyester-Degrading Bacterial Strains from Municipal Wastewater and Their Application in Microplastic Degradation in Contaminated Wastewater

Diverse synthetic polymers find their regular application in routine life and are disposed of directly into the environment through various sources. The released microplastic and microfibres from the sources creates contamination in both aquatic and terrestrial environments. When these micropollutants enter the food chain, they have adverse effects on the environment and human health. This study focuses on the application of native bacterial strains isolated for the effective degradation of polyester microfibers. The isolated bacterial strains, namely MFB 6, MFB 8, and MFB 11, tolerant to polyethylene glycol (PEG), were identified as Bacillus sp., Paenibacillus sp., and Aeromonas veronii, respectively, with NCBI gene bank accession numbers ON318306, ON318390, and PP237260. Polyester biodegradation efficiency of 10.5%, 12.6% and 8.4% was achieved by MFB 6, MFB 8 and MFB 11, respectively, after 42 days of investigation in minimal salt medium under shake flask condition. In future the application of these microorganisms will help in sustainable management of synthetic microfiber pollutants and find their suitable application in micro plastic degradation in contaminated wastewater.

Bridging gap between agro-industrial waste, biodiversity and mycelium-based biocomposites: Understanding their properties by multiscale methodology

A multiscale methodology approach was employed integrating microscopic analysis of the biomasses present in the biocomposite (lignocellulosic and fungal) to understand their macroscopic response in terms of physical and mechanical properties. Colombian native strain Ganoderma gibbosum, used for the first time in the production of biocomposites was cultivated on peach palm fruit peel flour and sugar cane bagasse wet dust, individually and as a mixture. During the solid-state fermentation were monitoring the change that occurred in substrate composition such as glucan, arabinoxylan, and lignin through biomass compositional analysis using structural carbohydrates and lignin. Moreover, fungal biomass formation was monitored via scanning electron microscopy. The resulting biocomposites underwent characterization through flexural and water absorption tests. Our findings indicated that G. gibbosum primarily degraded the polysaccharides in each of the evaluated media. However, lignin degradation to 15.06 g/g was only observed in the mixture biocomposite of peach palm fruit peel fluor and sugarcane bagasse wet dust in a ratio of 1꞉1, accompanied by a reduction in glucan and arabinoxylan weights to 26.1 and 7.72 g/g, respectively. This polymer degradation, combined with a protein-rich source in the mixture biocomposite of peach palm fruit peel fluor and sugarcane bagasse wet dust in a ratio of 1꞉1, facilitated the production of a fungal skin (biological matrix) with a high hyphal density of 65 %, contributing to Young's modulus of 3.83 MPa, elongation without failure, and low water absorption rate in this biocomposite (55 %). The lignocellulosic biomass in the culture media acted as a filler for mechanical interlocking with the matrix and provided attachment points for water absorption. Thus, our study establishes a connection between the microscopic scale and the macroscopic behavior of this biocomposite, assessing structural carbohydrates and lignin analysis during solid-state fermentation (SSF), laying the groundwork for a more customized design of mycelium-based biocomposites. Finally, this study demonstrates the possibility of tailoring nutrient composition by designing their culture media to obtain physical-mechanical properties according to the application requirement.

Bacteriological and Mycological Assessments of Second-Hand Wears Procured From Girei And Jimeta Markets, Adamawa State, Nigeria

Study’s Novelty/Excerpt This study investigates into the microbial contamination of second-hand clothes, highlighting their potential role in infection transmission. The research highlights the significant phosphate-solubilizing activity of these native strains, which enhances phosphorus availability to plants through the secretion of organic acids and enzymes. The findings underscore the need for public health interventions, including the washing and disinfection of second-hand clothing to mitigate the risk of spreading antibiotic-resistant pathogens. Full Abstract Used clothes can potentially be an element in the chain of infection transmission during normal daily activities. Second-hand wear is among such used clothes purchased by many people and used directly without considering any attending health implications. This study, therefore, examined the level of microbial contamination of second-hand clothes and the association between the different categories of the clothes and microbial contaminants. Second-hand clothes such as shirts, trousers, vests, socks, and shoes were bought from three Markets in Girei, Yola North and Yola South. Isolation of organisms was carried out via Standard Plate Count. Isolates were identified using morphology and appropriate biochemical methods. A chi-square test (P ≤ 0.05 significant) was done to analyze some of the data obtained. Antibiotic susceptibility of the bacterial isolates was also determined using the Kirby-Bauer method. The most frequently isolated bacteria were Staphylococcus aureus. Other bacteria isolated were Pseudomonas spp and E. coli. A total of four fungal species were isolated. These are Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger and Trichophyton rubrum. Trousers had the highest bacterial count (1.10 x103 CFU/mL) and fungal count (8.00 x104 CFU/mL). The data obtained shows no significant association between fungal species and the categories of clothes with (P = 0.15), but there is a significant association between bacterial species isolated and the categories of clothes analyzed (P = 0.02). S. aureus was susceptible to ciprofloxacin (100%) and erythromycin (92.8%), while Pseudomonas sp and E. coli were most susceptible to ciprofloxacin and sparfloxacin (100%). The least susceptibility was observed with amoxicillin and sulfamethoxazole-trimethoprim. It became obvious that these clothes are possible carriers of antibiotic-resistant pathogens for skin and other infections. Washing and disinfecting second-hand wear before use may be important in minimizing the potential health implications associated with the isolated pathogens.