Fungal Research Articles

Efficacy of Postharvest Application of Aureobasidium pullulans to Control White Haze on Apples and Effect on the Fruit Mycobiome

White haze, an emerging disorder caused by extensive fungal growth on the apple surface, results in a compromised fruit quality and decreased marketability. The use of biological control agents could be an interesting tool to reduce its development. This work aimed to test the efficacy of two Aureobasidium pullulans strains (AP2 and PL5) in controlling white haze on stored apples. An in vivo trial was conducted by inoculating fruits with white haze causal agents (Entyloma belangeri, Golubevia pallescens, Tilletiopsis washingtonensis) and treating them with the antagonistic yeasts. Three commercial biofungicides were also included in the trial. Both A. pullulans strains, along with the Metschnikowia fructicola-based product, reduced white haze incidence after 110 days of storage at 1 ± 1 °C and after 7 days of shelf life. Furthermore, the effect of A. pullulans application on the fruit fungal microbiome was assessed. A significant impact of apple matrix and treatment on the mycobiome composition was observed. Analyses showed a good colonization of A. pullulans on the treated apples, both epiphytically and endophytically. A decrease in white haze-related fungi abundance was observed in the treated fruits. Additionally, a reduction of Ramularia spp. and modifications in the abundance of other fungal genera were detected after storage and shelf life.

Pathogen producing aflatoxin in contaminated sandwich: Identification and preservation

The toxicity of the contaminated powder contributed to toxic aflatoxins has been well-known in the literature. However, before this study, the specific fungal strain behind aflatoxin production remained unidentified. Our research aimed to isolate and identify fungi from the tainted sandwiches while also assessing the preservation of sandwiches in ambient conditions. The study pinpointed Aspergillus flavus as the fungus responsible for aflatoxin production. Analysis revealed that the sandwich samples contaminated with pure A. flavus exhibited a significant Aflatoxin B1 (AFB1) concentration of 55.2 ± 0.21 ng/g, accompanied by a spore count of 2 × 106 Colony-Forming Unit (CFU)/g after ten days. In contrast, sandwich samples contaminated with the unspecified fungi displayed a lower AFB1 content of 16.21 ± 0.42 ng/g, with a spore count of 2.2 × 102 CFU/g after the same duration. In the prevention study, the efficacy of the ethanol spray method for inhibiting aflatoxin from A. flavus was investigated. Results demonstrated that a 70 % ethanol concentration at a ratio of 2.0 % total weight of the sandwich proved highly effective, significantly impeding fungal growth. This method extended the preservation time by sevenfold compared to the control. Importantly, tests at 2.0 % ethanol of the sandwich weight did not detect aflatoxin presence.

Effects of ethyl maltol on properties of starch-based active packaging: Morphology, volatile release and mold inhibition

Ethyl maltol, known for its caramel-like flavor and antimicrobial properties, blends compatibly with baked goods. In this study, ethyl maltol-incorporated starch films were developed as potential active food packaging materials. Films containing 0–10% ethyl maltol were prepared and characterized for their physicochemical, antimicrobial, and barrier properties. Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy confirmed interactions between ethyl maltol and starch, leading to modified thermal properties and enhanced film smoothness. Dynamic mechanical analysis revealed a shift in the relaxation temperature with increasing ethyl maltol content, indicating changes in polymer chain mobility. Water vapor permeability decreased with ethyl maltol incorporation, likely due to reduced hydrophilicity, while oxygen permeability increased, suggesting increased hydrophobicity. Ethyl maltol exhibited antifungal activity against Aspergillus niger, with a maximum inhibition zone of 1.53 mm at 10% loading. When incorporated into starch films, ethyl maltol effectively inhibited fungal growth in butter cake, extending its shelf life by up to three-fold. The controlled release kinetics of ethyl maltol from the films was analyzed using gas chromatography-mass spectrometry (GC-MS), revealing a linear release profile. These results demonstrate the potential of ethyl maltol-incorporated starch films as active, biodegradable food packaging materials with antimicrobial properties and significant shelf-life extension benefits.

EFEKTIVITAS HYDROGEL LIDAH BUAYA (ALOE VERA) TERHADAP RUAM POPOK (DIAPERS RASH) PADA BAYI 0 – 12 BULAN

Diaper rash occurs in approximately 25% of all babies born worldwide, with 6,840,507,000 experiencing diaper rash due to the use of diapers. The main causes of diaper rash are the growth of fungi and bacteria. Diaper rash can be treated using non-pharmacological therapy, one of which is the use of aloe vera gel. The purpose of this study is to prove the effectiveness of aloe vera gel in healing diaper rash in babies aged 0-12 months. This research was conducted in Kediri City from January to March. The sample in this study consisted of 36 baby respondents aged 0-12 months using random sampling. This study used a quasi-experimental design with a pretest-posttest control group design. The intervention group was given aloe vera hydrogel, while the control group was given zinc oxide ointment, then measured using the diaper dermatitis grading scale score. This study used the repeated measures ANOVA test. The results showed an average difference of 0.750 in the intervention group and 0.584 in the control group. It was shown that the effectiveness of healing diaper rash in the intervention group was 51.02%, and in the control group, it was 41.13%. Data analysis with a P-value < 0.05 indicated a difference in healing between the administration of zinc oxide and aloe vera in reducing diaper rash scores. The administration of aloe vera hydrogel is significantly effective in healing diaper rash in babies aged 0-12 months. Future research could use a narrower age range of babies.

In vitro antifungal activity and in vivo edible coating efficacy of insect-derived chitosan against Botrytis cinerea in strawberry

Strawberry is a perishable fruit, susceptible to development of rot by a range of fungi, in particular Botrytis cinerea. Chitosan represents an alternative to agrochemicals for improving shelf-life and fighting fungal pathogens. A chitosan-based coating derived from pupal exuviae of Hermetia illucens has been recently formulated for improving shelf-life of strawberry stored at 4 °C and mixed condition (4 °C and room temperature). The effects of a decolored (PEDEC) and not decolored (PEND) chitosan from the black soldier fly were evaluated and compared with commercial chitosans from crustaceans (CCs), in vitro and in vivo. An inhibition/reduction of fungal growth and a disturbance of normal fungal morphology were observed, being MIC of 0.5 mg mL−1 and 1 mg mL−1 and growth inhibition of 70 % and 4% for PEND and PEDEC, respectively. Both edible coatings distributed via aerograph showed equal or better potential application than CCs in controlling B. cinerea in strawberry post-harvest treated. Different effects for chitosans depended on their different molecular weight and deacetylation degree distributions, and the presence or absence of melanin pigments in their structure. PEND could act directly against the fungus, with effects predominantly associated with fungitoxic properties; PEDEC might principally provide viable alternatives, such as the elicitation of biochemical defense responses in fruits, for example through total phenols, in particular the flavonoids.

Self-inhibition of growth and allelopathy through volatile organic compounds in Fusarium solani and Aspergillus fumigatus.

Microbial volatile organic compounds (VOCs) emitted from fungi are known as their secondary metabolites from environmental sources. However, their physiological roles remain to be unclear. Even though the roles are still unknown, VOCs are deliberately released to convey information to both homologous and non-homologous organisms. We investigated the effects of single VOCs (hexanal, benzaldehyde, heptanal, 2-ethyl-1-hexanol, 3-octanone, 2-undecanone, 3-octanol, 2-Phenylethanol, 2-phenyl-2-propanol, phenylbenzaldehyde, 2-pentadecanone, β-trans-bergamotene, β-bisabolene, 2-methyl-5 -(1-methylethyl)pyrazine) on the fungal growth. In parallel, application of the co-culturing system in a growth chamber allowed free gas and VOCs exchange between emitter colonies of Fusarium solani and Aspergillus fumigatus, or between colonies of different growth stages of the same species. Distinct self-inhibition occurred by the emitters of fungal growing colonies against receiver ones on the stage of conidial germination or against the younger colonies at an earlier stage in both fungi. Similarly, the phenomenon of allelopathy appeared to work between growing colonies of F. solani and the germinating conidia or young colonies of A. fumigatus or vice versa. Solid phase microextraction-gas chromatography/mass spectrometry revealed VOCs compounds of each fungi. In F. solani, hexanal and benzaldehyde appeared to be significant inhibitors for colony growth. Benzaldehyde inhibited filamentous growth but not conidial germination. In A. fumigatus, heptanal seemed to be an equivalent effector. The inhibitory effect of benzaldehyde was more distinct on the A. fumigatus conidial germination than its filamentous growth.

Volatile Organic Compounds from Ceratocystis cacaofunesta, a Causal Agent of Ceratocystis Wilt of Cacao.

Fungi of the genus Ceratocystis are aggressive tree pathogens that cause serious diseases in several crops around the world. Ceratocystis wilt disease caused by C. cacaofunesta has been shown to be responsible for severe reductions in cacao production. In this study, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used in combination with chemometric analysis for monitoring volatile organic compounds (VOCs) released from C. cacaofunesta. Low-molecular-weight esters, alcohols, ketones, and sulphur compounds were identified in the liquid broth. Monitoring the volatile profile over five days of fungal growth revealed that the concentrations of alcohol and esters were inversely proportional. Acetate esters were responsible for the intense fruity aroma of the C. cacaofunesta culture produced within the first hours after fungal inoculation, which decreased over time, and are likely associated with the attraction of insect vectors to maintain the life cycle of the pathogen. PCA revealed that 3-methylbutyl acetate was the metabolite with the highest factor loading for the separation of the VOC samples after 4h of fungal growth, whereas ethanol and 3-methylbutan-1-ol had the highest factor loadings after 96 and 120h. 3-Methylbutan-1-ol is a phytotoxic compound that is likely associated with host cell death since C. cacaofunesta is a necrotrophic fungus. Fungal VOCs play important roles in natural habitats, regulating developmental processes and intra- and interkingdom interactions. This is the first report on the volatiles released by C. cacaofunesta.

Evaluation of the biocide activity of tomatine-rich extracts from tomato cannery residues against fungi and bacteria

Synthetic pesticides are discouraged for their environmental and health impacts, making research into alternatives essential. Several solutions of vegetal origin are being evaluated. The use of residual biomass from the agri-food system is particularly suitable due to its abundance and often unexplored potential. This study focuses on characterizing and assessing the activity of extracts obtained from wastes of the tomato cannery industry (including green fruit, stems, and leaves), which are rich in steroidal glycoalkaloids such as α-tomatine and tomatidine in different proportion. The antimicrobial activity of these extracts was tested on three bacterial strains belonging to the Escherichia coli (EC), Xanthomonas campestris (XC), and Bacillus pumilus (BP) species, as well as the phytopathogenic fungus Botrytis cinerea (BC). In particular, the mechanism of action of the extracts in relation to their surfactant properties was investigated, with the effect of the analytical standard serving as a reference. Both extracts showed strong inhibition of bacterial and fungal growth in vitro, with values reaching 100 %.The inhibitory effect was mainly due to the presence of α-tomatine in the extracts, which reached its aggregated state of micelle at the critical micelle concentration (CMC). Tomatidine, although known for its biocidal properties, did not contribute significantly due to its limited solubility. However, exceptions to this pattern were observed for extract rich in tomatidine, which exhibited efficacy at doses below the CMC. A possible explanation could be the enhanced solubility of tomatidine (which corresponds to enhanced bioactivity) in the presence of surfactant secreted by BP or as a consequence of the interaction between tomatidine and α-tomatine at the pre-micellar state for BC. In vivo assays with BC showed a reduction in symptoms comparable to that of a commercial fungicide available for organic agriculture, particularly at low concentrations. The relative content of α-tomatidine and tomatidine in the extracts modulated their bioactivity. An excess of tomatidine relative to α-tomatine led to a decrease in biocidal effect due to the chemical interactions among these species.

AfSwi6 Regulates the Stress Response, Chlamydospore Production, and Pathogenicity in the Nematode-Trapping Fungus Arthrobotrys flagrans.

Nematode-trapping (NT) fungi are a major resource for controlling parasitic nematodes. Arthrobotrys flagrans, as a typical NT fungus, can capture nematodes by producing three-dimensional nets. The APSES transcription factor Swi6 plays a vital role in fungal growth and the pathogenicity of pathogens. In this study, we characterized AfSwi6 via gene disruption using the homologous recombinant method and transcriptome sequencing. Knockout of the AfSwi6 gene caused defects in mycelial growth, trap formation and pathogenicity, chlamydospore production, and stress response. Moreover, the transcriptome data indicated that AfSwi6 was related to DNA repair, stress response, and plasma membrane fusion. The result showed that AfSwi6 has a significant effect on trap development and chlamydospore production in A. flagrans.

Phospho-code of a conserved transcriptional factor underpins fungal virulence

BackgroundCell wall integrity (CWI) is crucial for fungal growth, pathogenesis, and adaptation to extracellular environments. Calcofluor white (CFW) is a cell wall perturbant that inhibits fungal growth, yet little is known about how phytopathogenic fungi respond to the CFW-induced stress.ResultsIn this study, we unveiled a significant discovery that CFW triggered the translocation of the transcription factor CgCrzA from the cytoplasm to the nucleus in Colletotrichum gloeosporioides. This translocation was regulated by an interacting protein, CgMkk1, a mitogen-activated protein kinase involved in the CWI pathway. Further analysis revealed that CgMkk1 facilitated nuclear translocation by phosphorylating CgCrzA at the Ser280 residue. Using chromatin immunoprecipitation sequencing, we identified two downstream targets of CgCrzA, namely CgCHS5 and CgCHS6, which are critical for growth, cell wall integrity, and pathogenicity as chitin synthase genes.ConclusionsThese findings provide a novel insight into the regulatory mechanism of CgMkk1-CgCrzA-CgChs5/6, which enables response of the cell wall inhibitor CFW and facilitates infectious growth for C. gloeosporioides.

Improving Fungal Product Yield through Fast, Eco-friendly, and Cost-effective Chrom Genic Media Technology

The cost of commonly available culture media is a source of concern for many researchers, highlighting the need to explore more cost-effective alternatives or reduce the use of additives. Despite limited research in this area, efforts have been made to identify alternative culture media that are economically viable for cultivating microorganisms. This study explored the potential of beetroot extract as a cost-effective medium with col-or-inducing properties for fungal growth and as a chromogenic medium for testing lipase enzyme production efficiently as one of the rapid differential tests. The results indicated that Beetroot Agar Medium (BAM) offered significant cost savings in fungal cultivation while facilitating rapid fungal growth compared to other expensive and time-consuming media. Within a 3-4 day incubation period at a temperature range of 25-27 ˚C, all isolated fungi exhibited robust growth. Furthermore, the medium successfully served as a chromogenic differentiating medium by inducing fungi to produce lipase. These findings have broad implications for bio-technology and industrial applications, providing a sustainable and efficient alternative for microbial cultivation.

Effect of beeswax and coconut oil as natural coating agents on morphological, degradation behaviour, and water barrier properties of mycelium-based composite in modified controlled environment

Non-degradable coatings made of petroleum-based plastics hinder the degradation performance of products. This highlights the urgent need to develop biodegradable, bio-based coatings derived from renewable resources to create a more sustainable and greener world with a smaller environmental footprint. This study endeavours to examine the effects of beeswax and coconut oil additions on the morphological, degradation, and water-barrier properties of mycelium-based composite (MBC). Coconut oil is supplemented with varying amounts of beeswax, comprising 0, 20, 40, 60, 80, and 100 wt%. Dip coating is applied to prepare coated-MBC at 65 °C for 2 min. The coated-MBC is characterized by water absorption test, water loss measurement, density measurement, yeast and mould test, shrinkage measurement, weight loss measu rement, soil burial test, Scanning Electron Microscopy (SEM) and macroscopic appearance. Findings revealed that a higher composition of beeswax (80 BW) leads to lower water absorption ability (26.25 %) and no fungal growth for 36 days, in contrast to uncoated-MBC (0 BW), which are used as a reference sample.

Exploring Endophytic Fungi as Natural Antagonists against Fungal Pathogens of Food Crops.

The yield and quality of cultivated food crops are frequently compromised by the prevalent threat from fungal pathogens that can cause widespread damage in both the pre-harvest and post-harvest stages. This paper investigates the challenges posed by fungal pathogens to the sustainability and yield of essential food crops, leading to significant economic and food security repercussions. The paper critiques the long-standing reliance on synthetic fungicides, emphasizing the environmental and health concerns arising from their widespread and occasionally inappropriate use. In response, the paper explores the potential of biological control agents, specifically endophytic fungi in advancing sustainable agricultural practices. Through their diverse symbiotic relationships with host plants, these fungi exhibit strong antagonistic capabilities against phytopathogenic fungi by producing various bioactive compounds and promoting plant growth. The review elaborates on the direct and indirect mechanisms of endophytic antagonism, such as antibiosis, mycoparasitism, induction of host resistance, and competition for resources, which collectively contribute to inhibiting pathogenic fungal growth. This paper consolidates the crucial role of endophytic fungi, i.e., Acremonium, Alternaria, Arthrinium, Aspergillus, Botryosphaeria, Chaetomium, Cladosporium, Cevidencealdinia, Epicoccum, Fusarium, Gliocladium, Muscodor, Nigrospora, Paecilomyces, Penicillium, Phomopsis, Pichia, Pochonia, Pythium, Ramichloridium, Rosellinia, Talaromyces, Trichoderma, Verticillium, Wickerhamomyces, and Xylaria, in biological control, supported by the evidence drawn from more than 200 research publications. The paper pays particular attention to Muscodor, Penicillium, and Trichoderma as prominent antagonists. It also emphasizes the need for future genetic-level research to enhance the application of endophytes in biocontrol strategies aiming to highlight the importance of endophytic fungi in facilitating the transition towards more sustainable and environmentally friendly agricultural systems.

Chemical and genetic characterization of lipopeptides from Bacillus velezensis and Paenibacillus ottowii with activity against Fusarium verticillioides.

The fungus Fusarium verticillioides significantly threatens maize crops in tropical soils. In light of this, biological control has emerged as a promising strategy to reduce fungicide costs and environmental risks. In this study, we aimed to test the antifungal activity of cell-free supernatant (CFS) from three Bacillus velezensis (CT02, IM14, and LIS05) and one Paenibacillus ottowii (LIS04) against F. verticillioides, thereby contributing to the development of effective biocontrol measures. The research employed a comprehensive approach. The antifungal activity of the bacterial strains was tested using cell-free supernatant (CFS) from three Bacillus velezensis (CT02, IM14, and LIS05) and one Paenibacillus ottowii (LIS04). The UPLC-MS evaluated the CFS to identify the main bioactive molecules involved in the inhibitory effect on F. verticillioides. Scanning electron microscopy (SEM) was used to assess the impact of CFS on spores and hyphae, and genome sequencing was conducted to identify the genes involved in biological control. These robust methodologies ensure the reliability and validate our findings. The CFS of the four strains demonstrated significant inhibition of fungal growth. The UPLC-MS analysis revealed the presence of lipopeptides with antifungal activity, including surfactin and fengycins A and B expressed by the three strains of Bacillus velezensis and iturin A expressed by strains LIS05 and IM14. For Paenibacillus ottowii, fusaricidins, ABCDE, and five previously unreported lipopeptides were detected. Scanning electron microscopy (SEM) showed that treatments with CFS led to significant distortion and breakage of the F. verticillioides hyphae, in addition to the formation of cavities in the membrane. Genome mining confirmed the presence of genes coding for the lipopeptides identified by UPLC-MS, including the gene for iturin in CTO2. Genomic sequencing revealed that CT02, IM14, and LIS05 belong to different strains of Bacillus velezensis, and LIS04 belongs to Paenibacillus ottowii, a species recently described. The four bacterial strains, including three novel strains identified as Bacillus velezensis and one as the recently described species Paenibacillus ottowii, demonstrate significant potential as biocontrol agents for managing fungal disease. This finding underscores the novelty and potential impact of our research.

Analyzing the Effects of Monochromatic Lights on the Fungal Growth to Control the Progression of Microbial Deterioration on Animal Collections Preserved in the Zoological Museum of Naples, Italy

ABSTRACT Exposing artworks and artifacts in museums is fundamental to disseminate culture and knowledge but is also risky since the exposure to environmental conditions can deteriorate exhibited objects. Light is crucial, being able to trigger photochemical effects, and jointly responsible (with temperature and humidity) for biological risk generation. In this context, fungal growth in museum artifacts is a damaging factor that should not be underestimated. Consequently, the study of lighting effects on fungi development is essential. In this work, five different fungal strains (Aspergillus fumigatus, Bjerkandera adusta, Fusarium oxysporum, Penicillium chrysogenum, and Penicillium granulatum) isolated from samplings on animal exhibits hosted in the Zoological Museum of Naples, Italy, are cultivated inside four experimental boxes, equipped with monochromatic LEDs with different peak wavelengths (460 nm, 518 nm, 594 nm, and 638 nm). The growth rate, the protein and carbohydrate contents are analyzed and compared to results obtained in darkness (typical growth conditions for studies about fungi). Results demonstrate that, even if fungi are heterotrophic organisms and do not need light to grow and develop, their growth rate, and their protein and carbohydrate contents are affected by the exposure to monochromatic radiation, but the spectral sensitivity strictly depends on the analyzed species. For this reason, it is not possible to infer general practical guidelines for lighting applications, and it becomes urgent to establish accurate and shared analysis protocols to be applied case by case, to study the effects of the environmental conditions on microorganisms and drive-specific design choices.

Evaluation of antifungal activities of some Indian dietary spices against pathogenic Rhizopus arrhizus and Rhizopus stolonifer

Rhizopus arrhizus and Rhizopus stolonifer are pathogenic fungi responsible for causing ‘soft rot’ disease in fruits and vegetables, as well as life-threatening ‘mucormycosis’ in animals and humans, especially immunocompromised hosts. The use of synthetic fungicides and chemical preservatives to inhibit microbes is being challenged due to their toxic effects on human health and the environment. This has prompted researchers to investigate novel antimicrobials that are natural and safe. Current study aimed to evaluate the antifungal activities of essential oils (EOs), powdered (PWD) forms, and water extracts (WEs) of ten Indian dietary spices (Allium sativum (Als), Brassica nigra (Brn), Cinnamomum zeylanicum (Ciz), Cuminum cyminum (Cuc), Curcuma longa (Cul), Mentha piperita (Mep), Ocimum sanctum (Ocs), Syzygium aromaticum (Sya), Trigonella foenum-graecum (Trf), and Zingiber officinale (Zio)) against R. arrhizus (NCIM877) and R. stolonifer (NCIM1139). Spice agar method was used for investigating antifungal potential of PWD spices. Impregnated paper disc method and broth dilution technique were followed for screening the antifungal activities of EOs and WEs. Results revealed that EOs of six spices (Als, Brn, Ciz, Cuc, Mep, Sya), and PWD forms of four spices (Brn, Ciz, Cuc, Sya) inhibited the growth of both fungi in culture media, effectively. WEs of all ten spices remained ineffective in arresting the growth of tested fungal strains. R. stolonifer was found more sensitive compared to R. arrhizus towards tested substances. Based on these findings, further in vivo studies on PWD forms of Ccb, Ccm, and Sya and EOs of Als, Brn, Ccb, Ccm, Mep, Ocs and Sya may establish spices as ‘botanical antimicrobials’ to prolong the shelf life of valuable horticultural crops by arresting the growth of R. arrhizus and R. stolonifer.

Enhanced degradation of phototreated recycled and unused low-density polyethylene films by Pleurotus ostreatus.

Polyethylene, one of the most used petroleum-derived polymers, causes serious environmental pollution. The ability of Pleurotus ostreatus to degrade UV-treated and untreated recycled and unused (new) low-density polyethylene (LDPE) films was studied. We determined the fungal biomass production, enzyme production, and enzyme yield. Changes in the chemical structure and surface morphology of the LDPE after fungal growth were analyzed using FTIR spectroscopy and SEM. Functional group indices and contact angles were also evaluated. In general, the highest Lac (6013 U/L), LiP (2432 U/L), MnP (995 U/L) and UP (6671 U/L) activities were observed in irradiated recycled LDPE (IrRPE). The contact angle of all samples was negatively correlated with fermentation time; the smaller the contact angle, the longer the fermentation time, indicating effective biodegradation. The IrRPE samples exhibited the smallest contact angle (49°) at 4 weeks, and the samples were fragmented (into two pieces) at 5 weeks. This fungus could degrade unused (new) LDPE significantly within 6 weeks. The biodegradation of LDPE proceeded faster in recycled than in unused samples, which can be enhanced by exposing LDPE to UV radiation. Enzymatic production during fungal growth suggest that LDPE degradation is initiated by laccase (Lac) followed by lignin peroxidase (LiP), whereas manganese peroxidase (MnP) and unspecific peroxygenase (UP) are involved in the final degradation process. This is the first experimental study on the fungal growth and its main enzymes involved in LDPE biodegradation. This fungus has great promise as a safe, efficient, and environmentally friendly organism capable of degrading LDPE.

Preventing Fungal Spoilage from Raw Materials to Final Product: Innovative Preservation Techniques for Fruit Fillings.

Spoilage fungi are a significant cause of financial loss in the food and beverage industry each year. These fungi thrive in challenging environments characterized by low acidity, low water activity and high sugar content, all of which are common in fruit fillings used in pastry products. Fruit fillings are therefore highly susceptible to fungal spoilage. Fungal growth can cause sensory defects in foods, such as changes in appearance, odor, flavor or texture, and can pose health risks due to the production of mycotoxins by certain mold species. To reduce food loss and waste and extend product shelf-life, it is critical that we prevent fungal spoilage. Synthetic chemicals such as sorbic acid and potassium sorbate are commonly used as preservatives to prevent fungal spoilage. However, with consumer demand for 'natural' and 'chemical-free' foods, research into clean-label preservative alternatives to replace chemical preservatives has increased. The objectives of this review are (i) to provide an overview of the sources of fungal contamination in fruit filling production systems, from pre-harvest of raw materials to storage of the final product, and to identify key control factors; and (ii) to discuss preservation techniques (both conventional and novel) that can prevent fungal growth and extend the shelf-life of fruit fillings.

Development of active chitosan film containing bacterial cellulose nanofibers and silver nanoparticles for bread packaging.

The objective was to develop an active chitosan-based coating and to evaluate its effect on the shelf life and microbial safety of bread. Bacterial cellulose nanofibers (BCNF) and various levels (0.5%, 1%, and 2%) of silver nanoparticles (AgNPs) were in the chitosan (CS) film. Characterization of films was determined by analyzing WVP, ultraviolet barrier, and opacity as well as FTIR, XRD, DSC, TGA, and SEM. The water vapor permeability (WVP) of CS was remarkably (p < .05) decreased from 3.75 × 10-10 to 0.85 × 10-10 g/smPa when filled with BCNF and 2% AgNPs. Thermal and structural properties were enhanced in nanoparticle-included films. Applying CS/BCNF/AgNPs coatings for bread samples demonstrated a significant improvement in moisture retention and a decrease in the hardness (from 10.2 to 7.05 N for CS and CS/BCNF/1% AgNPs coated samples, respectively). Moreover, microbial shelf life of bread sample increased from 5 to 38 days after packaging with CS/BCNF/2% AgNPs film. After a storage period of 15 days at 25°C, no fungal growth was detected in bread samples which were coated with nanocomposite suspensions containing 1% and 2% AgNPs. However, at the same condition, yeast and mold counts was 7.91 log CFU/g for control sample. In conclusion, the CS/BCNF/2% AgNPs film might have the potential for use as active packaging of bread.

Changes in microbial physiology and carbon-use efficiency upon improving soil habitat conditions in conservation farming systems

The interplay between soil microbial anabolism and metabolism has recently been postulated as an important lever for carbon sequestration in soils. Theoretical considerations suggest that high microbial growth rates and a high carbon-use efficiency (CUE) are associated with increased soil organic carbon (SOC) build-up in arable soils. Nature-oriented conservation agricultural practices are believed to facilitate this microbial-driven process of SOC accrual; a practical validation of this postulation is however missing. Against this background, we evaluated the effect of agricultural management and site-specific soil chemical and physical properties on microbial physiology (i.e., respiration, bacterial and fungal growth rates, and microbial biomass turnover) and CUE by an on-farm comparison of conventional farming, conservation farming and unmanaged reference soil systems (i.e., adjacent field margins) at twenty-one sites across three soil depths. We show that a change in agricultural management towards soil health regeneration has a significant impact on microbial physiology. Bacterial growth, respiration and microbial biomass turnover increased from conventional farming towards conservation farming systems to reference soils. The opposite trend however was found for fungal growth and microbial CUE, with highest values observed in conventional farming systems. This clearly contradicts the prevailing idea that higher microbial CUE in conservation farming systems may be associated with higher SOC contents. Our results further show that soil physical and chemical parameters such as soil pH, texture and dissolved carbon compounds strongly predict microbial CUE. In line with these results, functional pore domains showed specific optima for microbial growth and CUE. For example, a high share of small pore domains hampered fungal growth and reduced microbial CUE but facilitated microbial biomass turnover at the same time. Thus, we suggest that – superimposed upon agricultural management effects – habitat structural conditions and microbial carbon limitation mainly shape microbial physiology and CUE in arable soil systems.