Rot Fungi Research Articles

Hydroponic Lettuce Cultivation with Organic Liquid Fertilizer: Examining Bacterial Inhibition and Phosphate Solubilization

This study explores organic hydroponic cultivation as a sustainable alternative to chemical fertilizers amid global supply challenges. With rising costs and the depletion of conventional nitrogen sources, organic liquid fertilizers are gaining attention for their microbial enrichment processes (MEP) that convert organic matter into plant-accessible nutrients. This experiment focuses on lettuce cultivation using two organic liquid fertilizers, Power Fish and POF vol. 2, in controlled environments. The results show that there are significant differences in plant growth parameters such as leaf number, fresh weight, chlorophyll content, and root length across different fertilizer treatments. Key findings include that effective management practices, including pH control and regular nutrient application, are crucial for maintaining microbial activity and optimizing nutrient uptake efficiency. Additionally, Bacillus sp. and Xanthomonas sp. were isolated from these fertilizers and dual-cultured with rot fungi, Pythium sp. and Fusarium sp. This dual cultivation demonstrated inhibitory activity against these pathogens, showcasing the potential of these microorganisms in promoting biofilm-mediated disease resistance in organic hydroponic systems. The study also emphasizes the phosphate solubilization capabilities of isolated bacteria, essential for sustainable nutrient cycling. Overall, organic hydroponic systems present a promising strategy for sustainable agriculture, reducing dependency on chemical inputs while enhancing crop productivity and resilience to environmental stressors.

Effect of Temperature, Relative Humidity, and Incubation Time on the Mycotoxin Production by Fusarium spp. Responsible for Dry Rot in Potato Tubers.

Potato is the fourth most consumed crop in the world. More than half of the crop is stored for three to nine months at cold temperatures (3-10 °C) for the fresh and seed market. One of the main causes of fresh potato waste in the retail supply chain is the processing of fungal and bacterial rots during storage. Dry rot is a fungal disease that mainly affects the potato crop during storage and is responsible for 1% of tuber losses in the UK. It is produced by Fusarium spp., such as Fusarium sambucinum and F. oxysporum, which can lead to the accumulation of mycotoxins in the potato tuber. Little is known about the impact of environmental factors on the accumulation of mycotoxins in potato tubers. Understanding the ecophysiology of these fungi is key to mitigating their occurrence under commercial storage conditions. Therefore, this work aimed to elucidate the effect of three different temperatures (5, 10, and 15 °C) and two different water activities (aw; 0.97, 0.99) on the ecophysiology and mycotoxin accumulation of F. sambucinum and F. oxysporum in a potato-based semi-synthetic medium. The mycotoxin accumulation was then studied in vivo, in potato tubers cultivated under organic farming conditions, stored for 40 days at 8.5 °C. Results showed that higher temperatures and aw enhanced fungal growth, lag time, and mycotoxin accumulation in vitro. Growth rate was 2 and 3.6 times higher when the temperature increased from 5 to 10 and 15 °C, respectively. Six different mycotoxins (T-2, HT-2, diacetoxyscirpenol, 15-acetoxyscirpenol, neosolaniol, and beauvericin) were detected in vitro and in vivo. T-2 was the most abundant mycotoxin detected in vitro, observing 106 ng of T-2/g media after 21 days of incubation at 10 °C and 0.99 aw. Due to the long period of time that potato tubers spend in storage, the fluctuations of environmental factors, such as temperature and relative humidity, could promote the development of fungal rot, as well as mycotoxin accumulation. This could result in important food and economic losses for the potato market and a threat to food safety.

Microorganisms Associated with Tomato (Lycopersicum Esculentum) Rot and Effect of Neem (Azadirachta Indica) Extract in Rot Control in Makurdi Metropolis, Benue State, Nigeria

Tomato (Lycopersicum esculentum) is a vital agricultural crop globally, yet it is significantly affected by various microbial pathogens leading to post-harvest rot, which threatens food security and economic stability. This study aimed to identify the microorganisms associated with tomato rot in Makurdi Metropolis and evaluate the efficacy of neem (Azadirachta indica) extract as a biocontrol agent. A total of 60 tomato fruits were sampled from the five major markets within the Makurdi metropolis. They were cultured on Nutrient agar, MacConkey agar, Potato Dextrose agar, Mannitol salt agar, and Eosin Methylene blue agar. The organisms identified were Klebsiella sp, Salmonella sp, Proteus vulgaris, Enterobacter sp, Shigella sp, Staphylococcus sp, Bacillus sp, Escherichia coli, Rhizopus sp, Mucor sp, Aspergillus sp, and Fusarium sp. Neem extract was used for susceptibility tests on the bacterial isolates at 10%, 50%, and 100% concentration, and it was found most effective on some bacterial isolates at higher concentrations of 100% with wider zones of inhibitions. Vegetative growth of the fungi on neem extract decreased with increase in concentrations. This finding proved the potentiality of plant extracts for controlling the fungal rot of tomato fruit. A pathogenicity test was conducted with readings taken at intervals of days and it was noticed that the microbial isolates were actually the cause of tomato rot. This study underscores the importance of identifying microbial threats to tomato crops and highlights neem extract as a promising natural alternative for managing tomato rot, promoting sustainable agricultural practices in Makurdi Metropolis and Nigeria at large.

Mycotoxicity of leaf extract of Tabernaemontana pachysiphon Stapf against Fusarium oxysporum Schlecht, a postharvest fungal rot pathogen of taro

Mycotoxicity of leaf extract of Tabernaemontana pachysiphon Stapf against Fusarium oxysporum Schlecht, a postharvest fungal rot pathogen of taro

Mycotoxicity of leaf extract of Tabernaemontana pachysiphon Stapf against Fusarium oxysporum Schlecht, a postharvest fungal rot pathogen of taro

Taro, otherwise known as cocoyam, is one of the major sources of calories in the tropics. However, losses of its corm during storage are high, partly due to pathogenic diseases. Fusarium oxysporum is one of the principal fungal pathogens causing about 50% of postharvest losses of taro corms in the tropics. The rise in pesticide-resistant fungal pathogens, amongst other factors, has necessitated the recent search for alternatives to synthetic pesticides. This work aimed to evaluate the effects of six concentrations (0%, 10%, 20%, 30%, 40%, and 50%) of aqueous leaf extract of T. pachysiphon on spore germination, mycelial growth and reproduction of F. oxysporum both in vitro and in vivo. The in vitro experiment was conducted using the poison bait technique, while the in vivo experiment involved 21 corms (200 g) artificially infected with F. oxysporum and treated with the respective concentrations of the test extracts or griseofulvin. The control consisted of fungus-infected corms only. Generally, the experiments consisted of 7 treatments replicated 3 times and were laid out in a completely randomized design. Results of the cultures studies showed that all aqueous extract of T. pachysiphon significantly (P< 0.05) and to varying degrees impeded spore germination (56.38–70.24%) and retarded radial growth of the pathogen (68.27–82.01%). The percentage rot expression in the living tissues treated with the extracts ranged between 19.4% and 40.4%. All results were statistically (P< 0.05) superior to the control but comparable to the results (75.06%, 86.41%, and 17.2%) obtained with griseofulvin for these features, respectively. The inhibitions were linearly correlated with the dose of application of the biotoxicant both in vitro and in vivo.

Iskanje in določanje bakterij, ki so sposobne razgraditi celulozo s pomočjo IAA kot potencialnih pospeševalcev rasti rastlin

Strains with both straw degradation and plant growth promotion ability were selected from the cultivated soil in Bac Kan, Vietnam to solve the problems of poor soil microbial diversity status, weak corrosion promotion effect, and poor crop growth caused by fungal rot diseases. Among seventeen bacteria isolated, strain NR1 presented the highest value for cellulase enzyme activity (Hydrolysis index = 24.8 mm), and IAA production (20.15 mg l-1), and was identified as Bacillus amyloliquefaciens Priest et al., 1987. Inoculation with NR1 significantly increased the rot promotion rate of straw under liquid fermentation by 54.71 % compared with the control and increased the root length and average diameter, and SPAD value of maize under soil culture by 18.3 %, 22.0 %, and 5.24 % respectively (p < 0.05). In addition, fertilizing 8 or 9 tons of NR1-degraded compost fertilizer per hectare had the best effect on the growth, development, and productivity of the L14 peanut variety. These results suggest strain NR1 could be used to produce multi-functional humus, accelerate the decomposition of straw in the cultivated soil, and promote crop growth.

In vitro antifungal activities of Cymbopogon citratus, Cymbopogon martini, Pogestemon cablin and Curcuma longa essential oils against spoilage fungi isolated from tomatoes

Tomatoes (Solanum lycopersicum L.) have highmoisture content (93–95%), making them more vulnerable to various types of spoilage fungi. Numerous medicinal plants' essential oils are known to have antifungal properties that combat these spoilage fungi. Therefore, this study aimed to investigate the potential antifungal activity of essential oils from some indigenous plants in Bangladesh to prevent the fungal attack on tomatoes. Using potato dextrose agar medium, 4 species of spoilage fungi from tomatoes were identified. ITS (Internal transcribed spacer) region-specific sequencing was used to identify the fungal species as Aspergillus welwitschiae, Aspergillus tamari, Penicillium citrinum and Rhizopus arrhizus. Assessment on antifungal activity was conducted for four essential oils extracted from plants: turmeric leaf (Curcuma longa), patchouli (Pogestemon cablin), palmarosa (Cymbopogon martini) and lemongrass (Cymbopogon citratus). The GC-MS method was used to analyze these essential oils to ascertain their chemical content. A pathogenicity test determined the severity and % of rot on tomatoes. A. welwitschiae caused the most severe spoilage (80%) after 21 days, while R. arrhizus damaged 26% of the tomatoes within 5 days. The minimal fungicidal concentration (MFC) and minimal inhibitory concentration (MIC) of the essential oils were determined after analysis. Lemongrass oil fully suppressed the growth of all the isolates at a concentration of 12 ????l/ml. Finally, the essential oils of palmarosa and lemongrass may be used as a preventative measure against tomato fungal rot.

Diversity and Pathogenicity of Fusarium Root Rot Fungi from Canola (Brassica napus) in Alberta, Canada.

Root rot disease poses a significant threat to canola (Brassica napus), underscoring the need for a comprehensive understanding of its causal agents for more effective disease mitigation. The composition and diversity of fungal pathogens associated with root rot of canola in Alberta, Canada, were evaluated from plant tissue samples collected in 2021 and 2022. The study revealed Fusarium spp. as the predominant pathogens found in almost all surveyed fields. Fusarium avenaceum, F. redolens, and F. solani were among the most frequently recovered species. Greenhouse trials confirmed their pathogenicity, with F. avenaceum and F. sporotrichioides found to be particularly aggressive. Additionally, F. sporotrichioides and F. commune were identified for the first time as canola root rot pathogens. Inoculation with isolates of most species resulted in significant reductions in seedling emergence, plant height, and shoot and root dry weights. Analysis of translation elongation factor 1-α (TEF-1α) and internal transcribed spacer (ITS) sequences confirmed the identity of the Fusarium spp., while concatenating the ITS and TEF-1α sequences enabled improved species differentiation. Geographic and year effects did not influence fungal diversity or aggressiveness, as determined by principal component analysis. This study emphasized the high diversity and impact of Fusarium spp. in causing canola root rot.

Effectiveness of Several GRAS Salts against Fungal Rot of Fruit after Harvest and Assessment of the Phytotoxicity of Sodium Metabisufite in Treated Fruit.

This study evaluates the efficacy of the salts sodium metabisulfite (SMB), ammonium bicarbonate, sodium bicarbonate, and potassium dihydrogen orthophosphate first in vitro against the main postharvest fruit rot fungi, Alternaria alternata, Botrytis cinerea, Penicillium italicum, and Penicillium digitatum. Results showed that 0.2% SMB completely inhibited the mycelium growth of the fungal species. Ammonium bicarbonate and sodium bicarbonate were less effective at 0.2% in inhibiting mycelial growth, ranging from 57.6% to 77.6%. The least effective was potassium dihydrogen orthophosphate. Experiments were also performed in vivo on wounded apples inoculated with the most pathogenic fungus, B. cinerea, and treated with SMB at concentrations of 0.2, 0.5, 1, 2, and 3%, both preventively and curatively. Results based on the decay size showed that SMB, when used as a preventive treatment, had a reduced efficacy, even with the highest concentration. However, this salt proved to be very effective at 0.5% in curative treatment since the decay was completely blocked. Our results suggest that the appropriate concentration of SMB for post-harvest treatment is 0.5% as a curative treatment. On the other hand, the 1% dose induced the onset of phytotoxicity around the wound. To assess the extent of the phytotoxicity reaction, higher concentrations of 1-4% SMB were applied to wounded fruit. Apples and oranges were inoculated or not with B. cinerea and P. digitatum, respectively. Doses of 1-4% induced phytotoxicity in the form of a discolored ring surrounding the wound on the epidermis of the fruit; this phytotoxicity enlarged as the concentration of SMB increased. The phytotoxic features were similar on apples and oranges. The methodological procedure made it possible to carry out a quantitative assessment of SMB phytotoxicity. This method is proposed as an easy-to-use technique for quantitatively estimating the phytotoxicity of antifungal compounds on post-harvest fruit.

Rast, razvoj i zdravstveno stanje jele (Abies alba Mill.) u Kantonu Sarajevo

Silver fir (Abies alba Mill.) stands as a pivotal tree species in Bosnia and Herzegovina, holding paramount ecological, economic, and sociological significance. Its role is fundamental in the context of uneven-aged forest management, a prevailing practice in the region. Contributing not only to biodiversity but crucially to the stability of our ecosystems, silver fir faces a discernible decline in recent times, attributed to the intricate interplay of abiotic and biotic factors. Among abiotic factors, the foremost influences include wind and fire, while within the realm of biotic factors, notable contributors to the decline encompass mistletoe, rot fungi, cancer, witches' brooms on fir, bark beetles, and fir moth miner. The silver fir exhibits remarkable responsiveness to increased light inflows, emphasizing the imperative to establish favorable conditions for its sustained growth and development throughout its life cycle. This collective understanding underscores the importance of addressing both abiotic and biotic factors to ensure the continued vitality of the silver fir in the unique ecosystems of Bosnia and Herzegovina

Efficacy of active and passive modified atmosphere packaging on quality preservation and storage life of pomegranate fruit and arils: A review

Pomegranate has nutritional value and health benefits due to its bioactive compounds and antioxidant properties. Fruit consumption is strongly recommended due to its high content of vitamins, fiber, minerals, and polyphenols. Supplying ready-to-eat pomegranate can be a beneficial technique to increase consumption with regard to its nutritional properties. However, maintaining nutritional quality and preventing microbial spoilage is a major challenge. Fruit quality is lost with visible symptoms such as weight loss, shriveling, husk scald, chilling injury, fungal rot, aril color degradation, and off-flavor during long-term storage. Therefore, it is very important to use appropriate strategies to maintain pomegranate whole fruit and aril quality. Gases around the product create a suitable environment for oxidative reactions and aerobic microorganism growth. Therefore, changing the atmosphere around the product can help maintain its quality. One of the effective methods to increase the postharvest life of products is to use modified atmosphere packaging (MAP), which reduces microbial spoilage and chilling injury, preserves the quality, and extends the shelf life by reducing the respiration rate. Modified atmosphere packaging, which uses natural atmospheric components (O2, CO2 and N2), has been widely accepted due to the lack of toxic residues on the product. This review discusses on recent research in terms of MAP application on quality properties and postharvest life of pomegranate fruit and arils during storage.

First description of adenosine production by Gnomoniopsis smithogilvyi, causal agent of chestnut brown rot

Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales) is the main causal agent of chestnut brown rot on sweet chestnut worldwide. The rotting of nuts leads to alterations in the organoleptic qualities and decreased fruit production, resulting in significant economic losses. In 2021, there was an important outbreak of chestnut rot in southern Galicia (Spanish northwest). The profile of secondary metabolites from G. smithogilvyi was studied, especially to determine its capability for producing mycotoxins, as happens with other rotting fungi, due to the possible consequences on the safety of chestnut consumption. Secondary metabolites produced by isolates of G. smithogilvyi growing in potato dextrose agar (PDA) medium were identified using liquid chromatography coupled with high-resolution mass spectrometry. Three metabolites with interesting pharmacological and phyto-toxicological properties were identified based on their exact mass and fragmentation patterns, namely adenosine, oxasetin, and phytosphingosine. The capacity of G. smithogilvyi to produce adenosine in PDA cultures was assessed, finding concentrations ranging from 176 to 834 µg/kg. Similarly, the production of mycotoxins was ruled out, indicating that the consumption of chestnuts with necrotic lesions does not pose a health risk to the consumer in terms of mycotoxins.

Piriformospora indica promotes plant growth, reduces lodging and enhances seed yield, and quality in onion (Allium cepa)

The onion seed crop is affected by several bacterial and fungal rot, which causes lodging, yield, and seed quality losses. In the present study the performance of three biocontrol agents- Piriformospora indica, Vesicular arbuscular mycorrhiza (VAM) and Trichoderma viride with fungicide and bactericide as a standard control in reducing lodging and enhancing the seed yield and quality in onion was evaluated. The results showed that among the bioagents, indica recorded the highest bulb germination (98.39%), highest plant stand (87.10%), umbel diameter (5.01 cm), and lowest lodging (27.56%). Whereas VAM recorded the highest plant height (53.53 cm). The performance of P. indica was equivalent to standard chemical control carbendazim for several characteristics and even superior in characteristics like–seed yield (22.60 g/plant) and seed quality traits like–1000-seed weight (3.69 g), and seed vigour index-II (209.76). These results suggest that onion bulb treatment with P. indica is beneficial in reducing pesticide use and lodging, and increasing the productivity and seed quality. To the best of our knowledge, this is the first report on the use of P. indica in onion seed crop. Onion seed crop is pollinated by insects, primarily by honeybees, which are highly susceptible to pesticide applications. Therefore, onion seed bulb treatment with P. indica can be an essential component of integrated crop management in onion seed production for sustainable agriculture.

DNA Barcoding of Cacao Pod Rot Fungi in Papua Province

Cocoa (Theobroma cacao) pod rot fungi have various types. In general, cause cocoa pod rot are fungi of the species Fusarium sp, Rhizoctonia sp, Phytium sp, Colletotricum sp, Amerosporium sp, Phomopsis sp and Phytopthora sp. Various species of fungi that can rot cocoa pods have high similarity in morphology characters even though the treatment for each species of fungi is different. This problem occurs in the people's nucleus cocoa plantations in the Yapsi district, Jayapura, Papua province. Samples of cacao pods infected with the fungus were taken and the isolates obtained were reinoculated into uninfected cacao pods. Isolates showing dominant infectivity were taken and identified molecularly. Identification was carried out by creating DNA barcoding by sequencing the Internal Transcribed Spacer (ITS) region of the 18SrDNA marker gene from the fungal isolates SP4DYAPSI-1, SP4 DYAPSI-2, SP3DYAPSI-1 and SP6DAUN3. Sequencing data in the form of isolate fungi DNA barcodes were analyzed with the ClustalX program analyses. The resulting phylogenetic tree construction shows that the four isolates are related to the fungus species Fusarium solani with a nucleotide similarity index above 95%. This shows that the cause of damage to cocoa pods in the Yapsi area, Jayapura, Papua, Indonesia is the fungus Fusarium solani.

Biological Control and Cross Infections of the Neofusicoccum spp. Causing Mango Postharvest Rots in Spain

Mango is one of the main subtropical crops growing in southern Spain. Spanish mango fruit production can be efficiently transported to the rest of Europe, and these mangoes are very appreciated for their quality and flavour. However, postharvest rots have been detected in stored mango fruits, making their commercialization difficult. The causal agents associated with such rot symptoms have been isolated and identified. Because the mango crops used to share the same growing area with avocado crops, fungal presence on surrounding asymptomatic avocado fruits was also analysed to detect potential cross infections. Artificial inoculation with Neofusicoccum parvum and N. mediterraneum was able to reproduce rot symptoms in mango but was also able to induce rots in avocado fruits. To approach a biological control strategy against these rot-producing fungi, two very well-known antagonistic biocontrol bacteria, Pseudomonas chlororaphis PCL1606, and Bacillus velezensis UMAF6639, were tested. The obtained results revealed that both bacteria can control the fungal rots on stored mango and avocado fruits under controlled conditions. Additionally, the strain B. velezensis UMAF6639 showed the ability to persist on the fruit surface of adult commercial trees in experiments under open field conditions, helping to prevent the appearance of these postharvest diseases.

A circular economy approach: A new formulation based on a lemon peel medium activated with lactobacilli for sustainable control of post-harvest fungal rots in fresh citrus fruit

The aim of the study was to develop an effective bio-formulation for preventing post-harvest fungal rots in fresh citrus fruit through a multi-step process that includes isolation and characterization of lactic acid bacteria (LABs) from citrus fruit peel, selection of LAB strains with high antifungal activity, chemical characterization of cell free supernatants (CFS), formulation of a lemon peel powdery-based medium (LM) activated with LAB fermentates, chemical characterization of fermented LM, and evaluation of the efficacy of the new bio-formulation against blue mold. Thirteen LABs were recovered from the rind of citrus fruit and identified by the peptide mass fingerprinting method. The antifungal activity of LABs, isolated from citrus fruit, as well as cell free supernatants (CFSs), obtained from their liquid cultures, was tested against diverse plant pathogenic fungi and oomycetes, using the dual-culture overlay and the diffusion agar assays, respectively. Two isolates designated as N3B2 and M2B2, both identified as Lactiplantibacillus plantarum, were selected among the others for their relevant antifungal activity. Both isolates showed a broad spectrum antagonistic activity comprising also major postharvest pathogens of citrus fruit, such as Penicillium digitatum and P. italicum, the causal agents of green and blue moulds, respectively, Alternaria alternata, Colletotrichum gloeosporioides, C. karsti, Phytophthora citrophthora and Ph. nicotianae. The N3B2 and M2B2 isolates were used as starter cultures to ferment a lemon peel powder medium enriched with a nutrient water solution (LM). The two formulations obtained by fermenting LM with the N3B2 and M2B2 isolates showed a strong in vitro inhibitory activity on the same broad range of pathogens used in the preliminary screening of LABs. Moreover, the two LM-based formulations reduced the severity of blue mold infection and inhibited the sporulation of P. italicum on artificially inoculated lemon fruit. The chemical analysis of LM-based bioformulations revealed their antifungal activity was very probably due to the LAB-derived acidic components, including lactic, acetic, DL-3-phenyllactic, 3-4-dihydroxyhydrocinnamic, salicylic acid vanillic acids. These innovative LM-based bioformulations activated with LAB-derived antifungal compounds will be exploited as edible and biodegradable fruit coatings to prolong the shelf-life and prevent post-harvest rots of fresh citrus fruit.

Involvement of Fenton Reaction on Biodecolorization and Biodegradation of Methylene Blue Dye by Brown Rot Fungi <i>Daedalea dickinsii</i>

The disposal of dye wastewater has become a major global concern. Meanwhile, microorganisms have shown high potential in the treatment of wastewater pollutants. In this study, the involvement of the Fenton reaction in the biodecolorization and biodegradation of methylene blue (MB) by the brown rot fungus Daedalea dickinsii was investigated. Subsequently, D. dickinsii is a fungus capable of producing hydroxyl radicals (•OH). This experiment was conducted with an initial MB concentration of 75 mg/L, and different incubation times of 0, 7, 14, 21, and 28 d respectively. The result showed that the Fenton reaction played an important role, and this was demonstrated by the addition of FeSO4 as a Fe2+ source. The removal of MB by D. dickinsii with the addition of Fe2+ reached 91.454% at 28 d in a mineral salt medium. It was higher compared to D. dickinsii culture treatment without Fe2+ addition, 86.427%. Furthermore, the metabolic degradation product was analyzed using LC-TOF/MS and identified as 2-amino-3-hydroxy-5-(methylamino) benzenesulfonic acid and N-(3,4-dihydroxy phenyl)-N-methyl formamide.

Management Of Pre And Post Harvest Fruit Rot Diseases Of Ber

The main focus of this research is to produce the good quality and disease free fruits. In this aspect, the investigation was carried out to reduce or control the pre and post-harvest fungal fruit rot. The study on pre and post-harvest management of fruit rot diseases of ber caused by Alternaria and Colletotrichum was carried out and the results showed that two pre-harvest sprays of Thiophanate Methyl (0.1 %) at 15 day intervals during the marble stage of ber fruit was found effective against Alternaria fruit rot recorded 6.8 PDI compared to untreated control recorded 43.6 PDI. Two pre-harvest sprays of 0.1 per-cent carbendazim at 15 day intervals was found effective against Colletotrichum fruit rot during the pea fruit stage of ber recorded 6.6 PDI compared to untreated control recorded 44.2 PDI. The post-harvest studies revealed that dipping of ber fruits in 2 per cent sodium chloride solution for 10 min. recorded the lowest PDI of 5.27 against post-harvest fungal rot as compared to untreated control recorded 25.27 PDI.

The First Evidence of Potential Antibacterial Activity of Laccase Enzyme from Indonesian White Rot Fungi against Pathogenic Bacteria

The antibacterial agent can be extracted from plants, animals, and microorganisms such as fungi. The potential antibacterial activity of laccase derived from fungi remains limited in current reports. This study aimed to investigate the characteristics of laccase from Indonesian white rot fungi (WRF) and explore its potential as an antibacterial agent. The laccases were produced by Trametes hirsuta D7, Trametes hirsuta EDN 082, Leiotrametes menziesii BRB 73, and Lentinus sajor-caju BRB 12 using oil palm empty fruit bunch as a substrate. The results showed that the Indonesian WRF tested produced brownish-yellow laccase. FTIR analysis demonstrated similar peak patterns but distinct absorption intensities among the laccases. Trametes hirsuta D7 gained 0.044 U/ml of the greatest laccase activity. Laccase, with minimal activity of 0.001 U/ml–0.026 U/ml, suppressed the propagation of Propionibacterium acnes and Staphylococcus aureus. Escherichia coli and Pseudomonas aeruginosa could be inhibited by the laccase with a minimum activity of 0.002 U/ml–0.044 U/ml. However, S. aureus and E. coli showed the Minimum Bactericidal Concentration in the laccase activity range of 0.018 U/ml–0.308 U/ml. Gram-positive and Gram-negative bacteria grow more slowly when the laccase is present, supposed the laccase as a potential antibacterial agent.

Study on the influence of visible molds on primary and secondary shelf life of pasteurized gnocchi

Primary (PSL) and secondary shelf life (SSL) of pasteurized fresh gnocchi were assessed. The dependence of the SSL on the extent of deteriorative reactions at the package opening was also predicted. To the aim, industrial gnocchi samples were produced, packaged, pasteurized, transported to the lab, and then stored at room temperature (20 °C) for more than 1 year. During this storage period, some samples were opened at five increasing times form the production and stored under different storage conditions to monitor microbiological and sensory quality, pH, moisture content and appearance of visible molds. Results demonstrate that packaged gnocchi remained acceptable for about 12 months and then were refused for appearance of visible molds. Results on SSL assessment demonstrate that temperature after package opening plays a key role on the appearance of fungal rot on the product surface. Unsealed samples stored at 4 °C remained acceptable for maximum 4 weeks, whereas samples at 20 °C were refused within 1 week from the opening. The data obtained in this study were also used to test the predictive ability of the proposed mathematical model. Considering the simplicity of the hypothesis used to derive the model, its predictive ability can be considered quite acceptable.