Mold Penicillium Research Articles

The technology of soft Camembert cheese with the usage of different bacterial preparations

The aim of the work was to develop a technology of soft Camembert cheese from pasteurized cow's milk using various bacterial preparations and to investigate its basic physicochemical and organoleptic properties. Two experimental samples of cheese were made: sample 1 – culture of direct application of mesothermophilic type RSF-742 + culture of white mold (Penicillium candidum + Geotrichum candidum) + rennet enzyme + calcium chloride; sample 2 – culture of direct application of mesophilic type CHN-19 + culture of white mold (Penicillium candidum + Geotrichum candidum) + rennet enzyme + calcium chloride. The finished product analyzed by the organoleptic and physicochemical parameters. Syneretic properties of rennet clots were studied after the process of fermentation and coagulation at a temperature of 32 ºC. The sample with the use of CNH-19 was characterized by the best consistency and pronounced mushroom and creamy aroma. Sample № 1, made with the bacterial preparation RSF-742, was characterized by a less pronounced aroma and structure, typical of Camembert cheese. It was found that the sample №1 (RSF-742) was characterized by higher syneretic properties. According to syneretic properties, lower moisture content characterized sample 1 (62 %) versus sample 2 (64 %). The volume of serum released in 1 hour was 65 % for sample 1 and 62 % for sample 2. The highest values for the fat content was sample 1 – 43 %, and sample 2 – 42 %. The content of salt did not differ, in sample № 1 – 1.8 % and in sample № 2 – 1.75 %. There were changes in the active acidity of the finished product when using different bacterial preparation. Lower pH values in sample 1 – 6.2, and slightly higher in sample 2 – 6.5 were observed. The highest number of points according to the results of the score was given to sample № 2 – 86 points, sample № 1 – 77 points out of possible 100.

Domestication of the Emblematic White Cheese-Making Fungus Penicillium camemberti and Its Diversification into Two Varieties

Domestication involves recent adaptation under strong human selection and rapid diversification and therefore constitutes a good model for studies of these processes. We studied the domestication of the emblematic white mold Penicillium camemberti, used for the maturation of soft cheeses, such as Camembert and Brie, about which surprisingly little was known, despite its economic and cultural importance. Whole-genome-based analyses of genetic relationships and diversity revealed that an ancient domestication event led to the emergence of the gray-green P.biforme mold used in cheese making, by divergence from the blue-green wild P.fuscoglaucum fungus. Another much more recent domestication event led to the generation of the P.camemberti clonal lineage as a sister group to P.biforme. Penicillium biforme displayed signs of phenotypic adaptation to cheese making relative to P.fuscoglaucum, in terms of whiter color, faster growth on cheese medium under cave conditions, lower amounts of toxin production, and greater ability to prevent the growth of other fungi. The P.camemberti lineage displayed even stronger signs of domestication for all these phenotypic features. We also identified two differentiated P.camemberti varieties, apparently associated with different kinds of cheeses and with contrasted phenotypic features in terms of color, growth, toxin production, and competitive ability. We have thus identified footprints of domestication in these fungi, with genetic differentiation between cheese and wild populations, bottlenecks, and specific phenotypic traits beneficial for cheese making. This study has not only fundamental implications for our understanding of domestication but can also have important effects on cheese making.

Biotransformation of Flaxseed Oil Cake into Bioactive Camembert-Analogue Using Lactic Acid Bacteria, Penicillium camemberti and Geotrichum candidum.

This study aimed at investigating the antioxidant activity, oxidative stability, physicochemical and microbial changes of innovative vegan Camembert-analogue based on flaxseed oil cake (FOC) which was produced using lactic acid bacteria (LAB), mold Penicillium camemberti (PC) and yeast Geotrichum candidum (GC). Two variants were prepared, namely with LAB + PC and LAB + PC + GC. After fermentation for 24 h at room temperature, the samples were stored for 14 days at 12 °C and maturated for 14 days at 6 °C. Changes in microbial population, polyphenolics, flavonoids, radical scavenging capacity were evaluated. Additionally, textural changes, pH, acidity, levels of proteins, free amino acids, reducing sugars, oil content and its oxidative stability were determined. Results showed that LAB as well as fungi were capable of growing well in the FOC without any supplementation and the products were characterized by a high antioxidant potential (high polyphenolics and flavonoids contents as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide (O2−) and hydroxyl (·OH) radicals scavenging activity). This study has demonstrated that bioactivity as well as the physicochemical properties depend on the starter culture used. Due to functional and biochemical characteristics conferred to the obtained Camembert-analogues, the use of P. camemberti and G. candidum showed a potential for industrial application. There is a potential for these products to be used where non-dairy alternatives are desired.

Pretreatment of the Antagonistic Yeast, Debaryomyces hansenii, With Mannitol and Sorbitol Improves Stress Tolerance and Biocontrol Efficacy.

The effect of exogenous mannitol and sorbitol on the viability of the antagonist yeast, Debaryomyces hansenii, when exposed to oxidative and high-temperature stress was determined. Results indicated that both the 0.1 M mannitol (MT) and 0.1 M sorbitol (ST) treatments improved the tolerance of D. hansenii to subsequent oxidative and high-temperature stress. MT or ST cells had a significantly higher level of cell survival, elevated the gene expression of catalase 1 (CAT1) and copper-zinc superoxide dismutase (SOD1), as well as the corresponding enzyme activity. Treated cells also exhibited a lower accumulation of intracellular reactive oxygen species (ROS), and a higher content of intracellular mannitol and sorbitol relative to non-treated, control yeast cells, when exposed to a subsequent oxidative (30 mM H2O2) or heat (40.5°C) stress for 30 min. Additionally, MT and ST yeast exhibited a higher growth rate in kiwifruit wounds, and a greater ability to inhibit postharvest blue mold (Penicillium expansum) and gray mold (Botrytis cinerea) infections. The present study indicates that increased antioxidant response induced by mannitol and sorbitol in D. hansenii can enhance stress tolerance and biocontrol performance.

Clinical Utility of Anaerobic and Fungal Blood Cultures in the Pediatric Oncologic Population.

If there is a concern for sepsis in a pediatric patient an aerobic blood culture is obtained. A febrile or ill oncology patient will often be evaluated with aerobic, anaerobic, and fungal blood cultures. There is to our knowledge little evidence to confirm the added benefit of broadly obtaining these cultures. A retrospective analysis of blood cultures from patients in the oncology and hematopoietic stem cell transplant wards at Children's National Medical Center between January 2010 and April 2017. Positive anaerobic and fungal cultures were evaluated for corollary positive aerobic cultures from the same time frame (+/-24 h). Unique isolates were designated as those positive anaerobic and fungal cultures without positive aerobic cultures and evaluated with detailed chart review. A total of 10,950 cultures were evaluated during the study period: 6579 aerobic, 2391 anaerobic cultures, 1980 fungal. In total, 419 positive aerobic, 140 positive anaerobic, and 43 positive fungal cultures were reviewed. Among these, 22 unique anaerobic cultures and 21 unique fungal cultures met case criteria. Only 7 cultures of obligate anaerobes were observed: 4 Clostridial spp., 2 Propionobacterium acnes, and 1 Peptostreptococcus spp. Thirteen of 21 fungal isolates consisted of a single colony and were regarded as probable contaminants. Penicillium, Cladosporium, and dematiaceous molds were in greatest frequency. Potential risk factors for patients with breakthrough isolates were evaluated and described. There is little increased yield from the use fungal and anaerobic blood cultures in addition to aerobic blood cultures in the routine evaluation of pediatric oncology and bone marrow transplant patients. Fungal and anaerobic blood cultures and should be reserved for cases with high clinical suspicion.

Characterization of Respiratory Pathogens in Contemporary Lung Transplant Recipients

This study assessed respiratory pathogens isolated in the first year post lung transplant in a recent multicenter cohort. Prior studies may not reflect current practices in antimicrobial prophylaxis and molecular diagnostics. We examined 499 consecutive bronchoalveolar lavage (BAL) samples for microbial isolates in 82 lung transplant recipients (LTR) enrolled in the prospective Genomic Research Alliance for Transplantation from July 2015 to 2017. Isolates were examined for species, timing: early (0-1 months post-transplant (MPT), intermediate (1-6 MPT), and late (6-12 MPT), and associated lung function decline. 389 microbes were isolated in 499 BAL samples, representing 348 unique episodes, over a median of 196 days. Bacterial isolates were more common in the early and intermediate periods, and fungal and viral pathogens more common in the late period. In non-Cystic Fibrosis (CF) populations, the frequencies of most common bacterial isolates S. aureus, P. aeruginosa, and enteric Gram Negative Bacteria were 15.6%, 12.6%, 23.0%, compared to 28.0%, 30.0%, and 18.0% respectively, in CF LTRs. The most common viral pathogens were rhinovirus (60.6%), and enterovirus (12.7%). Non-invasive molds (Penicillium etc) comprised 73.3% of fungal isolates, with potentially invasive molds (Aspergillus, Mucor sp.) isolated in 12.9% of cases. Notably, there were only two isolates of Aspergillus fumigatus (2.0%). 48/389 isolates (12.3%) were associated with > 10% reduction in FEV1 at 90 days post isolation of which rhinovirus was the most frequent isolate (11/48). In a contemporary cohort, bacterial pathogens predominate in the early post-transplant period, while fungal and viral pathogens are more common later. Pseudomonas and Aspergillus sp. comprised a smaller proportion of total than previously described, and do not appear to associate with early lung function decline. Further studies are underway to determine the conditions in which select infections impact early lung function.

Independent domestication events in the blue-cheese fungus Penicillium roqueforti.

Domestication provides an excellent framework for studying adaptive divergence. Using population genomics and phenotypic assays, we reconstructed the domestication history of the blue cheese mould Penicillium roqueforti. We showed that this fungus was domesticated twice independently. The population used in Roquefort originated from an old domestication event associated with weak bottlenecks and exhibited traits beneficial for pre‐industrial cheese production (slower growth in cheese and greater spore production on bread, the traditional multiplication medium). The other cheese population originated more recently from the selection of a single clonal lineage, was associated with all types of blue cheese worldwide except Roquefort, and displayed phenotypes more suited for industrial cheese production (high lipolytic activity, efficient cheese cavity colonization ability and salt tolerance). We detected genomic regions affected by recent positive selection and putative horizontal gene transfers. This study sheds light on the processes of rapid adaptation and raises questions about genetic resource conservation.

Domestication of the Emblematic White Cheese-Making Fungus <i>Penicillium camemberti</i> and Its Diversification into Two Varieties

Domestication involves recent adaptation under strong human selection and rapid diversification, and therefore constitutes a good model for studies of these processes. We studied the domestication of the emblematic white mold Penicillium camemberti, used for the maturation of soft cheeses, such as Camembert and Brie, about which surprisingly little was known, despite its economic and cultural importance. Whole genome-based analyses of genetic relationships and diversity revealed that an ancient domestication event led to the emergence of the gray-green P. biforme mold used in cheese-making, from the blue-green wild P. fuscoglaucum fungus. Another much more recent domestication event led to the generation of the P. camemberti clonal lineage from P. biforme. Both these domestication events were associated with strong bottlenecks. Penicillium biforme displayed signs of phenotypic adaptation to cheese-making relative to P. fuscoglaucum, in terms of its whiter color, faster growth on cheese medium under cave conditions, lower levels of toxin production and greater ability to prevent the growth of other fungi. The P. camemberti lineage displayed even stronger signs of domestication for all these phenotypic features. We also identified two differentiated P. camemberti lineages linked to different kinds of cheeses with contrasted phenotypic features in terms of color, growth, toxin production and competitive ability. We have, thus, identified footprints of domestication in these fungi, with genetic differentiation between cheese and wild strains and specific phenotypic traits beneficial for cheese-making. This study has not only fundamental implications for our understanding of domestication but can also have important impacts on cheese-making.

Rapid Phenotypic and Metabolomic Domestication of Wild Penicillium Molds on Cheese.

Fermented foods provide novel ecological opportunities for natural populations of microbes to evolve through successive recolonization of resource-rich substrates. Comparative genomic data have reconstructed the evolutionary histories of microbes adapted to food environments, but experimental studies directly demonstrating the process of domestication are lacking for most fermented food microbes. Here, we show that during adaptation to cheese, phenotypic and metabolomic traits of wild Penicillium molds rapidly change to produce domesticated phenotypes with properties similar to those of the industrial cultures used to make Camembert and other bloomy rind cheeses. Over a period of just a few weeks, populations of wild Penicillium strains serially passaged on cheese had reduced pigment, spore, and mycotoxin production. Domesticated strains also had a striking change in volatile metabolite production, shifting from production of earthy or musty volatile compounds (e.g., geosmin) to fatty and cheesy volatiles (e.g., 2-nonanone, 2-undecanone). RNA sequencing demonstrated a significant decrease in expression of 356 genes in domesticated strains, with an enrichment of many secondary metabolite production pathways in these downregulated genes. By manipulating the presence of neighboring microbial species and overall resource availability, we demonstrate that the limited competition and high nutrient availability of the cheese environment promote rapid trait evolution of Penicillium molds.IMPORTANCE Industrial cultures of filamentous fungi are used to add unique aesthetics and flavors to cheeses and other microbial foods. How these microbes adapted to live in food environments is generally unknown as most microbial domestication is unintentional. Our work demonstrates that wild molds closely related to the starter culture Penicillium camemberti can readily lose traits and quickly shift toward producing desirable aroma compounds. In addition to experimentally demonstrating a putative domestication pathway for P. camemberti, our work suggests that wild Penicillium isolates could be rapidly domesticated to produce new flavors and aesthetics in fermented foods.

Decay control and quality of individually film-wrapped lemons treated with sodium carbonate

The efficacy of 3-min-dip treatments with 3% sodium carbonate solutions at 20 or 50 °C was tested on lemons individually, not hermetically, sealed within low density polyethylene (LDPE) bags. Before sealing, treated lemons were rinsed (SCR) or not rinsed (SC) with fresh water. SC treatment almost completely inhibited green mold (Penicillium digitatum) development in wound-artificially inoculated lemons both wrapped and not wrapped after 15 d at 5 °C followed by 7 d at 20 °C or in those stored for 10 d at 20 °C. In SCR lemons, decay control was inferior, especially in wrapped lemons treated at 20 °C. Similar results were achieved with sound fruit inoculated 24 h before the treatments and stored for 30 d at 20 °C. SC and, at a less extent, SCR treatments increased dramatically mass loss of un-wrapped fruit compared to control fruit, whereas in wrapped fruit overall mass loss was almost completely inhibited. Wrapping the fruit in LDPE bags allowed to maintained fruit freshness and firmness and chemical quality along the whole storage time, regardless the treatments.

New Sulfur Organic Polymer-Concrete Composites Containing Waste Materials: Mechanical Characteristics and Resistance to Biocorrosion.

The aim of this study was to develop new sulfur-copolymer concrete composites using waste compounds that have good mechanical characteristics and show a resistance to biocorrosion. The comonomers used to synthesize the sulfur–organic copolymers were—90 wt. % sulfur; 5 wt. % dicyclopentadiene (DCPD); 5 wt. % organic monomers, styrene (SDS), 1-decene (SDD), turpentine (SDT), and furfural (SDF). The concrete composites based on sulfur–organic copolymers were filled with aggregates, sand, gravel, as well as additives and industrial waste such as fly ash or phosphogypsum. The sulfur–organic copolymers were found to be chemically stable (softening temperature, thermal stability, melting temperature, amount of recrystallized sulfur, and shore D hardness). Partial replacement of DCPD with other organic comonomers did not change the thermal stability markedly but did make the copolymers more elastic. However, the materials became significantly stiffer after repeated melting. All the tested copolymers were found to be resistant to microbial corrosion. The highest resistance was exhibited by the SDS-containing polymer, while the SDF polymer exhibited the greatest change due to the activity of the microorganisms (FTIR analysis and sulfur crystallization). The concrete composites with sulfur–organic copolymers containing DCPD, SDS, SDF, fly ash, and phosphogypsum were mechanically resistant to compression and stretching, had low water absorbance, and were resistant to factors, such as temperature and salt. Resistance to freezing and thawing (150 cycles) was not confirmed. The concrete composites with sulfur–organic copolymers showed resistance to bacterial growth and acid activity during 8 weeks of incubation with microorganisms. No significant structural changes were observed in the SDS composites after incubation with bacteria, whereas composites containing SDF showed slight changes (FTIR and microscopic analysis). The concrete composite containing sulfur, DCPD, SDS, sand, gravel, and fly ash was the most resistant to microbiological corrosion, based on the metabolic activity of the bacteria and the production of ergosterol by the molds after eight weeks of incubation. It was found that Thiobacillus thioparus was the first of the acidifying bacteria to colonize the sulfur concrete, decreasing the pH of the environment. The molds Penicillium chrysogenum, Aspergillus versicolor and Cladosporium herbarum were able to grow on the surface of the tested composites only in the presence of an organic carbon source (glucose). During incubation, they produced organic acids and acidified the environment. However, no morphological changes in the concretes were observed suggesting that sulfur–organic copolymers containing styrene could be used as engineering materials or be applied as binders in sulfur-concretes.

Synthesis, characterization and antimicrobial activity of nalidixic acid derivatives with spirohydantoins

This article presents the synthesis of a series of amides, based on the interaction of several 3-aminospirohydantoins with nalidixic acid. The target compounds were characterized by physicochemical parameters, IR, 1H and 13C NMR spectral data. The antimicrobial activity of the products obtained was determined against Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis, Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa and Salmonella abony, the yeasts Candida albicans and Saccharomyces cerevisiae and the molds Penicillium chrysogenum and Aspergillus niger. The relationship between structure and biological activity of the products obtained was discussed. It was found that the most effective compounds are tetralin (5f) and indane (5g) derivatives, which exhibit a pronounced antimicrobial activity against both tested Gram-positive and Gram-negative bacteria.

Salicylic acid and jasmonic acid can suppress green and blue moulds of citrus fruit and induce the activity of polyphenol oxidase and peroxidase

Abstract The ability of salicylic acid and jasmonic acid to suppress post-harvest infection with green mould Penicillium digitatum and blue mould P. italicum on three citrus species Citrus reticulata ‘Kinnow’, C. limon ‘Meyer Lemon’, and C. limetta ‘Mosambi’ was evaluated in a dose-response study. Salicylic acid (SA) and jasmonic acid (JA) were applied to the fruits as a post-harvest dip treatment followed by wound inoculation with the pathogens. Both resistance inducers caused a significantly lower disease severity compared with the infected but non-treated control, whereas disease incidence was not significantly lower than in the control. The efficacy of both SA and JA in reducing disease severity was concentration-dependent; the use of higher concentrations resulted in a greater degree of suppression. All the Citrus species tested in this study showed different responses in terms of disease development. C. limon ‘Meyer Lemon’ showed the highest disease development, and C. limetta ‘Mosambi’ the lowest. To get an insight into the mechanisms underlying the increase in resistance, the activity of defence-related enzymes – peroxidase (POD) and polyphenol oxidase (PPO) – was recorded in SA- and JA-treated fruit peelings. The activity of both enzymes was directly proportional to the concentration of the SA and JA applications. The highest activity of PPO and POD was observed in C. reticulata ‘Kinnow’ and the lowest in C. limon ‘Meyer Lemon’ fruits. This study is the first to document an increase in the activity of PPO and POD in SA- and JA-treated Citrus species in the presence of blue mould and green mould pathogens.

Ageritin, a Ribotoxin from Poplar Mushroom ( Agrocybe aegerita) with Defensive and Antiproliferative Activities.

Ribotoxins make up a group of extracellular rRNA endoribonucleases produced by ascomycetes that display cytotoxicity toward animal cells, having been proposed as insecticidal agents. Recently, the ribotoxin Ageritin has been isolated from the basidiomycetes Agrocybe aegerita (poplar mushroom), suggesting that ribotoxins are widely distributed among fungi. To gain insights into the protective properties of Ageritin against pathogens and its putative biotechnological applications, we have tested several biological activities of Ageritin, comparing them with those of the well-known ribotoxin α-sarcin, and we found that Ageritin displayed, in addition to the already reported activities, (i) antibacterial activity against Micrococcus lysodeikticus, (ii) activity against the tobacco mosaic virus RNA, (iii) endonuclease activity against a supercoiled plasmid, (iv) nuclease activity against genomic DNA, (v) cytotoxicity to COLO 320, HeLa, and Raji cells by promoting apoptosis, and (vi) antifungal activity against the green mold Penicillium digitatum. Therefore, Ageritin and α-sarcin can induce resistance not only to insects but also to viruses, bacteria, and fungi. The multiple biological activities of Ageritin could be exploited to improve resistance to different pathogens by engineering transgenic plants. Furthermore, the induction of cell death by different mechanisms turns these ribotoxins into useful tools for cancer therapy.

The Antimicrobial and Wound Healing Potential of Opuntia ficus indica L. inermis Extracted Oil from Tunisia.

Introduction Opuntia ficus indica L. inermis (OFI) is used in traditional medicine pharmacopeia for its richness in natural bioactive compounds. It has been proven to be effective in the improvement of the healing of laser-induced skin burns. The aim of the present study was to investigate the wound healing effect of OFI extracted oil on full-thickness skin wound. Materials and Methods The OFI seeds were firstly isolated from mature prickly pears, washed, dried, and then cold-pressed. The antimicrobial activities of OFI seed oil were estimated in vitro against bacteria, yeast, and fungi. Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) were calculated. Skin wound healing was investigated using an excisional wound healing model in rats. The skin wounds of three experimental groups of rats were topically treated once/day with saline solution (control group), 0.15 mg/mm2 of a reference drug Esth'Elle Pharma Cicaplaie cream (reference group), and 0.6 μl/mm2 of OFI seed oil (OFI oil group). The healing process was monitored daily and the percentage of wound contraction was calculated. A histological study was carried on skin biopsies. Results The extracted oil has shown an interesting antimicrobial effect on Enterobacter cloacae, antiyeast effect against Candida parapsilosis and Candida sake, and antifungal activity against three opportunistic cutaneous molds (Penicillium, Aspergillus, and Fusarium). Moreover, OFI oil has shown a good wound healing effect. It prevents cutaneous infections and reduces the reepithelialization phase. Conclusion OFI extracted oil has in vitro antimicrobial/fungal properties and in vivo wound healing activity. It seems to be efficient in the treatment of cutaneous infections and the promoting of the scarring process.

Trehalose increases the oxidative stress tolerance and biocontrol efficacy of Candida oleophila in the microenvironment of pear wounds

Harvested fruit tissues produce reactive oxygen species (ROS) in response to wounding. ROS production is further elevated when biocontrol yeasts are introduced into the wounds, where they act as a bio-elicitor and this results in an environment in which the biocontrol yeast is subject to oxidative stress. In the present study, the effect of trehalose, a non-reducing disaccharide and a major reserve carbohydrate, on the level of oxidative stress tolerance of the biocontrol yeast Candida oleophila was examined in wounded pear fruits. Results indicated that the level of trehalose in C. oleophila yeast cells increased when they were cultured in a trehalose-containing medium. Exposure to a trehalose-medium and the increase in internal trehalose improved the adaptation of C. oleophila to the oxidative environment present in pear fruit wounds. Trehalose-treated cells exhibited a lower accumulation of ROS and mitochondrial impairment compared to untreated, control cells when they were introduced into wounded pear fruit. The trehalose treatment up-regulated the expression of antioxidant genes, including peroxisomal catalase and thioredoxin reductase, in yeast cells. Trehalose-treated yeast also exhibited a faster growth rate in pear wounds and greater biocontrol efficacy against blue mold (Penicillium expansum) and Alternaria rot (Alternaria alternata) than untreated, control yeast. These results support the premise that trehalose improves the biocontrol efficacy of C. oleophila via the activation of antioxidant defense systems which support a faster rate of growth of the yeast in wounds of pear fruit.

Effect of high temperature with Litsea cubeba Pers. to control mold growth on bamboo food packaging and its possible modes of action

This study examined the effect of high temperature and Litsea cubeba oil with its main components against molds (Aspergillus niger, Aspergillus flavus, Penicillium sp., Penicillium cyclopium, Rhizopus sp., Fusarium sp., and Cladosporium sp.) on bamboo food packaging. Response surface methodology (RSM) with X1 (concentration of L. cubeba oil at 100, 300, and 500 mg g-1), X2 (temperature at 60, 80, and 100 °C), and X3 (time at 12, 14, and 16 h) was used to find the inhibitory periods of natural mold on packaging plates. The physical properties and the change of chemical components on the bamboo packaging plate before and after temperature treatment were determined to find the mode of action using gas chromatography–mass spectrometry (GC-MS). High temperature (at 100 °C) was a good inhibitor of all mold growth with the MIC (minimum inhibitory concentration) of 300 mg g-1; without heat treatment, no MIC was found. In addition, it was found that by using 300 mg g-1 of L. cubeba oil at 100 °C with an exposure time of 12 h, spore germination on the bamboo surfaces was completely inhibited for at least 290 days. After using high temperature, citral was detected on the surface of the packaging plates. Therefore, these components could be the key factors for inhibiting molds.

Meyve Sularında Patulin Kirlenmesi ve Kontrol Önlemleri

Patulin is a mycotoxin produced by some Penicillium, Aspergillus, and Byssochlamys mold species . It has been found to impose many adverse health effects, and frequently detection in commercial fruit juices and apple products makes it a public health concern. The most important organism responsible for the patulin contamination in apple and derived products is Penicillium expansum ( P . expansum ) . There have been many studies on inhibition of P . expansum growth in apples/fruits and reduction of patulin contamination in fruit products, however, it still remains as a major contamination problem in these products all around the world. Patulin contamination in apple and other fruit derived products could be prevented by the use of various physical, chemical, and biological control methods. The preventive measures such as Good Pre-harvest and Post-harvest Practices in combination with processing hurdles could be the best solution to avoid the contamination. Research and development to improve the current technologies, understanding and optimization the novel technologies also could serve the best to eliminate the problem.

1128. Utility of Anaerobic and Fungal Blood Cultures in the Pediatric Oncologic Population

BackgroundIn our institution, a febrile or ill appearing oncology patient will often be evaluated with aerobic, anaerobic, and fungal cultures. This is especially true in patients with persistent fevers without a clear etiology on empiric antimicrobial therapy. It is common for all three cultures to be repeated multiple times per admission.Although this practice may seem sensible, there is to our knowledge little evidence to confirm its necessity in this population.MethodsA record of all positive blood cultures originating from our institutions oncology ward was obtained from January 2010 to April 2017. Duplicate cultures (obtained on consecutive days with repeat organisms) were excluded. Each anaerobic and fungal culture was then evaluated for corollary positive aerobic cultures from the same time frame.ResultsA total of 10,950 blood cultures were evaluated for this study, including 2,391 anaerobic cultures and 1,980 fungal cultures. Forty-two unique anaerobic cultures (1.7%) were identified. The viridans group of Streptococcus was a large contributor with nine unique cultures. Only seven cultures of obligate anaerobes were observed: four cultures of Clostridial species, two Propionobacterium acnes, and one Peptostreptococcus species. Twenty-three unique fungal cultures (1.2%) were identified. Notably most of these isolates (14) were identified as having one colony present and regarded as probable contaminants. Penicillium, Cladosporium, and unidentified dermatiaceous molds were present in greatest frequency.ConclusionOver a 7-year period of routinely obtaining anaerobic and fungal cultures for febrile oncology patients only 42 unique anaerobic and 23 unique fungal cultures were identified. Given the predominance of facultative anaerobes, this may simply reflect the findings of increased blood sampling rather than added utility of the growth medium. Similarly, even among the limited unique fungal cultures the majority were of suspect validity given the presence of a single colony. These findings suggest judicious use of selective growth media in cases with higher clinical suspicion may be more useful than empiric evaluation. Disclosures All authors: No reported disclosures.

ERRONEOUS DIAGNOSIS OF PENICILLIN ALLERGY BASED ON MOLD HYPERSENSITIVITY TESTING COMPLICATING TREATMENT OF RHEUMATIC FEVER

Introduction The penicillin allergy label puts a patient at risk for higher mortality and increased rates of severe infections. We present a case of treatment for rheumatic fever with Sydenham chorea complicated by erroneously labeled penicillin allergy due to mold hypersensitivity. Case Description A 12-year old female became unable to stand from full-body choreiform movements and was found to have rheumatic fever. Her echocardiogram showed: “rheumatic carditis, thickened mitral valve leaflets.” Two months prior, she had group A streptococcus pharyngitis treated with cephalexin due to a label of penicillin allergy. Skin testing performed by her local ENT physician had been positive to penicillium mold and she was counseled to avoid all penicillin antibiotics. Penicillin antibiotic was not tested, and she had never had penicillin. She passed a penicillin oral challenge and was transitioned to monthly intramuscular penicillin G benzathine. Discussion An erroneous penicillin allergy label prevented prompt treatment of this patient's condition with gold standard therapy. Despite optimal adherence, oral prophylaxis options show increased rheumatic fever recurrence compared to parenteral therapy. Alternative medications such as sulfadiazine can have severe side effects including hepatitis and agranulocytosis. This case emphasizes the need to educate patients and providers that hypersensitivity to penicillium mold does not equate hypersensitivity with the penicillin antibiotic it secretes. Furthermore, authentication of a penicillin allergy label continues to be of utmost importance in allowing patients to receive optimal therapy.