Mold Populations Research Articles

New Refined Experimental Analysis of Fungal Growth in Degraded Bio-Based Materials

When exposed to different building environmental conditions, bio-composite materials, such as hemp mortars, represent a risk of mold proliferation. This later plays a critical role in the biodeterioration of the materials when their physical properties are locally modified by the natural aging process. The primary objectives of the present work are first to assess the evolution of the surface of contaminated mortar; second, to investigate an accurate DNA extraction method that could be used for both bio-composite mortars and their fiber sources collected in situ; then, to understand the process of the proliferation of mold strains on both hemp shives and hemp mortar; and finally, to compare mold strains present in these phases to show their relationship to mold contamination and their impact on human health. In situ hemp mortar contamination behavior was investigated in the region of Pau (France) two months after hemp mortar application in extreme conditions (high humidity, low temperature, no aeration), which did not match the standard conditions under which hemp mortar must be used. The SEM observations and FTIR and pH analyses highlighted the decrease in pH level and the presence of organic matter on the mortar surface. DNA sequencing results showed that hemp shives were the main source of fungal contamination of hemp mortar. A mold population analysis showed that the most dominant phylum was Ophistokonta, which represented 83.6% in hemp shives and 99.97% in hemp mortar. The Acrostalagmus genus representatives were the most abundant, with 42% in hemp shives and 96% in hemp mortar. The interconnection between the mold strain characteristics (particularly the ability to grow in extreme environments) and the presence of hemp mortar was emphasized.

PSXII-9 Effects of lauric acid- and hops-based products on select microbial populations of aerobically exposed silage

Abstract Air exposed silages can harbor spoilage and pathogenic microbes which can reduce the palatability, nutritive quality and microbial safety of these feedstuffs. Accordingly, effective, environmentally friendly interventions are sought to rescue the biological and economical value of spoiled silages. The objectives of this study were to test the effects of treating air exposed corn silage with LipoVital GL-45, a Berg + Schmidt GmbH & Co. KG (Hamburg, Germany) product containing 45% monoglyceride of lauric acid (mixed within a 50% di/triglyceride base) alone or mixed with either Chinook or Galena hops or with an experimental extract containing hops β-acids. All treatments were administered as a warm water spray to deliver 1.6% product to the silage on a dry matter basis. Silage samples collected after 24 h ambient incubation were serially diluted in 0.4 M sodium phosphate buffer (pH 6.4) and plated to 3M Petrifilm for enumeration of yeast and molds and total aerobes as well as to Rogosa SL for enumeration of lactic acid bacteria and streptococci. Fluid samples from sampled silage were also inoculated in 10-fold increments to triplicate sets of tubes containing anaerobically prepared Reinforced Clostridial agar supplemented cellobiose and xylose (0.05% wt/vol each) for most probable number enumeration of total anaerobes. Populations of presumptive spore-forming aerobes and anaerobes were measured as described above except inocula were heated to 80 oC for 10 min to kill vegetative cells. An analysis of variance (Statistix Analytical Software, Tallahassee, FL, USA) revealed no treatment effects on yeasts and mold populations (P > 0.05) after 24 h air exposure of the silage, with counts averaging (± SD) 5.0 ± 0.7 log10 CFU/g. Silage treated with combinations of LipoVital GL-45 with Galena hops or the β-acid extract had 0.8 to 0.9 log10 units fewer (P < 0.05) lactic acid bacteria after 24 h air exposure than untreated controls (7.4 ± 0.1 log10 CFU/g). Similarly, silage treated with the LipoVital GL-45/Galena hops combination had 0.6 to 0.7 log10 units fewer (P < 0.05) heat-sensitive and presumptive spore-forming aerobes after 24 h air exposure when compared with controls (5.5 ± 0.2 and 5.2 ± 0.2 log10 CFU/g, respectively). Conversely, most probable numbers of nonheated anaerobe populations were lower (P < 0.05) in silage treated with LipoVital GL-45 combined with the β-acid extract when compared with controls (8.6 ± 0.x and 9.9 ± 0.7 log10 cells/g) with all other treatments being similar to controls. Populations of presumptive spore-forming anaerobes in the air exposed silage were unaffected by treatments, averaging 8.3 ± 0.7 log10 cells/g. Results warrant further research to investigate whether optimized dosages and formulations of LipoVital GL-45, Galena hops and β-acid extracts may ultimately yield treatments to prevent spoilage of air-exposed silages.

Effect of the Bioprotective Properties of Lactic Acid Bacteria Strains on Quality and Safety of Feta Cheese Stored under Different Conditions.

Lately, the inclusion of additional lactic acid bacteria (LAB) strains to cheeses is becoming more popular since they can affect cheese's nutritional, technological, and sensory properties, as well as increase the product's safety. This work studied the effect of Lactiplantibacillus pentosus L33 and Lactiplantibacillus plantarum L125 free cells and supernatants on feta cheese quality and Listeria monocytogenes fate. In addition, rapid and non-invasive techniques such as Fourier transform infrared (FTIR) and multispectral imaging (MSI) analysis were used to classify the cheese samples based on their sensory attributes. Slices of feta cheese were contaminated with 3 log CFU/g of L. monocytogenes, and then the cheese slices were sprayed with (i) free cells of the two strains of the lactic acid bacteria (LAB) in co-culture (F, ~5 log CFU/g), (ii) supernatant of the LAB co-culture (S) and control (C, UHT milk) or wrapped with Na-alginate edible films containing the pellet (cells, FF) or the supernatant (SF) of the LAB strains. Subsequently, samples were stored in air, in brine, or in vacuum at 4 and 10 °C. During storage, microbiological counts, pH, and water activity (aw) were monitored while sensory assessment was conducted. Also, in every sampling point, spectral data were acquired by means of FTIR and MSI techniques. Results showed that the initial microbial population of Feta was ca. 7.6 log CFU/g and consisted of LAB (>7 log CFU/g) and yeast molds in lower levels, while no Enterobacteriaceae were detected. During aerobic, brine, and vacuum storage for both temperatures, pathogen population was slightly postponed for S and F samples and reached lower levels compared to the C ones. The yeast mold population was slightly delayed in brine and vacuum packaging. For aerobic storage at 4 °C, an elongation in the shelf life of F samples by 4 days was observed compared to C and S samples. At 10 °C, the shelf life of both F and S samples was extended by 13 days compared to C samples. FTIR and MSI analyses provided reliable estimations of feta quality using the PLS-DA method, with total accuracy (%) ranging from 65.26 to 84.31 and 60.43 to 89.12, respectively. In conclusion, the application of bioprotective LAB strains can result in the extension of feta's shelf life and provide a mild antimicrobial action against L. monocytogenes and spoilage microbiota. Furthermore, the findings of this study validate the effectiveness of FTIR and MSI techniques, in tandem with data analytics, for the rapid assessment of the quality of feta samples.

The Ensiling melon biomass with different levels of inclusion of ground corn

The aim of this study was to evaluate silages produced with different mixtures of melon biomass and different levels of ground corn. The experiment was conducted under a completely randomized design in factorial scheme (3 × 4), with four replications. The first factor consieted of three mixtures of plant (branch and leaf) and fruit (melon; scraps) on natural matter (NM) as follows: 0, 100 and 1000 g kg-1 fruit. The second factor consisted of the use of different amounts of ground corn (0, 50, 100 and 200 g kg-1). Experimental silos with capacity for 5 kg and density of 500 kg m-3 were used. After 90 days, the silos were opened and the evaluations were carried out. The data were subjected to analysis of variance and the means were analyzed through the Tukey’s test (fermentative losses, chemical composition, aerobic stability), Scott-Knott test (microbiology and organic acids) and regression, and were compared with a significance level of p<0.05. The best dry matter results were obtained in silages with 0, 100 and 1000 g kg-1 fruit combined with 200 g kg-1 ground corn, which averaged 289.4, 290.4 and 264.1 g kg-1, respectively. Quadratic behavior was observed for effluent losses in silages with 100 g kg-1 fruit presenting a minimum value of 46.8 e and a maximum 56.2 kg t-1 NM. Regarding the mold population count, the highest values were obtained in silages with 100 g kg-1 fruit and 50 g kg-1 ground corn. Silages with 100 and 1000 g kg-1 fruit in melon biomass and 200 g kg-1 ground corn presented superior quality indicators, characterizing these biomass mixtures as the most suitable for silage making.

Pengaruh penambahan Lactobacillus plantarum dalam pembuatan mie kering berbahan rambut jagung manis (Zea mays var. Saccharata)

Rambut jagung manis is one of the agricultural waste products that is still minimally processed. One form of processed rambut jagung manis as a basic ingredient for making dry noodles. However, the resulting noodle product has a weakness in the form of a short shelf life due to the presence of spoilage fungi such as mold. Therefore, efforts need to be made to reduce the amount of mold by adding Lactic Acid Bacteria (L. plantarum). The method used in this research was an experimental method with a completely randomized factorial design (RALF), namely factor I L. plantarum concentration (0%, 2%, 4%, 6% (v/v)) and factor II storage time (0 days, 5 days, and 10 days) with 3 repetitions, so that 36 experimental units were obtained. The parameters measured in this study were the degree of acidity (pH), mold numbers, and nutritional value. The results showed that the average mold number at T0 was 3.40 ± 0.109 in dry noodles made from corn silk which were fermented without adding L. plantarum. Meanwhile at concentrations of 2%, 4% and 6% respectively as follows 3.24 ± 0.174; 3.30±0.240; and 3.34 ± 0.000. Mold content (Aspergillus sp.). Nutrient content tests after storage on the 10th day (T2) in L. plantarum concentration treatments of 0%, 2%, 4%, and 6% showed protein levels of 16.05%; 18.13%; 20.04%; and 20.36% bw and glucose levels respectively 78.87%; 83.16%; 81.56%; and 78.84%. The numerical value of yeast mold population in mie from rambut jagung during storage can be reduced and the protein content increases so that the addition of L. plantarum can be used as food biopreservative.

The antimycotic potential of Debaryomyces hansenii LRC2 on Iberian Pork Loins with low concentration preservatives

The use of preservatives such as nitrite and salt is a widespread practice in meat industry. For many years it has resulted in benefits like extending the shelf life of cured meat products. The EU has published new regulations to reduce the content of preservatives in foods as recent investigations have concluded that its excessive usage is related to health issues, so new alternatives are needed. Debaryomyces hansenii is a non-conventional yeast with known biocontrol possibilities. It can be found in many of environments and is the most frequent yeast isolated from sausages and dry meat products. The LRC2 strain used in this work is an isolate from Iberian Pork Loin, characterized biochemically and molecularly. The potential of D. hansenii LRC2 strain was evaluated following a volatile compounds inhibition assay. Then a scale-up trial was performed by inoculating a battery of Iberian Pork loins followed by a quality study of the final product. This was carried out through physical and microbial analysis as the identification of volatile compound profiles with GC-IMS. Finally, sensory tests were performed by a group of trained panellists and regular consumers. Results in our research show that the production of volatile compounds from LRC2 inhibited the activity of unwanted molds in all the conditions studied. The inhibition rates surpassed 75% in all cases, strengthening the hypothesis of its potential preservative effect in cured meat products. When testing the yeast inoculation effect and the reduction of preservatives in Iberian Pork Loins, a loss of sensory quality is observed when preservatives are drastically reduced reducing the panellists’ grades by more than 3 points on a 1–9 scale in overall quality. In all conditions, the LRC2 inoculated loins showed significant fewer mold populations than the non-inoculated ones, improving the safety food level of the final product. This study confirms that the application of natural yeast-based alternatives is a feasible option for the new meat industry needs.

Revalorization of agave bagasse in the obtention of type II sourdough inoculated with Lactococcus lactis NRRL B-50307

Sourdough is an ancient culture comprising flour and water, and fermented to allow leavening capacity from wild yeasts, producing bread that is preferred by the consumers. Agave bagasse (AB) is an abundant by-product in Mexico, rich in fiber and carbohydrates, but mostly wasted. This work aimed to revalorize AB as an ingredient for wheat sourdough. Different ratios (5%, 10%, and 15%, by weight) of AB powder were mixed with wheat flour, hydrated with 10% (w/v) water, and incorporated with Lactococcus lactis (NRRL B-50307). The fermentation was monitored for 6 days; physicochemical parameters (pH, titratable acidity [TTA], leavening capacity) were analyzed, and sourdough bread was produced. The population of lactic acid bacteria, yeasts, and molds, and adaptation of the added strain were monitored. Leavening capacity increased during fermentation, and L. lactis grew about 2 log CFU/day. Analysis of the sourdough showed a pH range of 3.6–4.9, and TTA ranged from 8 mg/mL to 11 mg/mL of lactic acid. Proximate analysis (%, w/w) revealed 28.95 ± 0.4 protein, 12.33 ± 0.98 fat, 37.68 ± 0.65 total carbohydrates, and 1.04 ± 0.32 ash. Sourdough bread added with AB + L. lactis showed significantly higher (p < 0.05) firmness (35.42 N ± 0.034 N) and volume (70.24 mL ± 4.67 mL) than using wheat only (20.48 N ± 4.04 N, and 49.10 mL ± 6.35 mL, respectively). AB is a good source of fiber and other compounds like minerals, suggesting its potential as a food ingredient, and encouraging the agave industry towards more sustainable development.

Benefits of isochoric freezing for carrot juice preservation.

Isochoric freezing (IF) at -5°C/77 and -10°C/100MPa was used to preserve carrot juice for 12 weeks. The juice qualities were compared to those using heat treatment (HT) at 95°C for 15s followed by cold storage at 4°C. The native population of total aerobic bacteria, yeasts, and molds in isochoric frozen juice remained below the detection limit for 12 weeks. In comparison, microbes started to grow in heat-treated juices after 3 weeks of refrigeration. The color of isochoric frozen juice appeared more deep orange than the fresh juice due to an increase in carotenoid extractability. IF was not effective in reducing the activities of peroxidase, polyphenol oxidase, and pectin methyl esterase compared with HT. However, the isochoric samples showed higher carotenoid content, polyphenol content, and antioxidant capacity compared to the fresh and heat-treated juices. PRACTICAL APPLICATION: Isochoric freezing was used to produce carrot juice with extended shelf life. Isochoric freezing could be a beneficial alternative to conventional heat treatment for carrot juice processing as the applied pressures reached total inactivation levels of spoilage microorganisms. Moreover, the low processing temperatures better retained desirable compounds and quality attributes of fresh juice throughout its shelf life.

Comparison of controlling capabilities of lactobionic acid, nisin, and K-Sorbate against dairy-borne Staphylococcus aureus, Escherichia coli, and mold in soft cheese.

The utilization of chemical preservatives holds the promise of effectively controlling microbial growth in soft cheese. The first trial aimed to compare the effectiveness of lactobionic acid (LBA) and K-Sorbate in controlling the proliferation of Staphylococcus aureus, Escherichia coli, and mold in white soft cheese. The subsequent part of the study explored the inhibitory effects of K-Sorbate, nisin, and LBA on mold populations in cheese whey. Two sets of soft cheese were produced. One set was contaminated with S. aureus, while the other was with E. coli, each at concentrations of 1 log CFU/ml and 1 log CFU/100 ml. Different concentrations of LBA were incorporated into these sets of cheese. Similar cheese samples were treated with K-Sorbate. For the subsequent part of the study, it was manufactured and divided into groups that inoculated with LBA with different concentrations, K-Sorbate, and nisin. With higher S. aureus inoculation, by day 18, the positive control exhibited growth exceeding 5 log CFU/g. In contrast, the LBA treatment dropped below limit of detection (LOD) and K-Sorbate yielded 4.8 log CFU/g. While with lower S. aureus inoculation, the positive control reached log CFU/g, while LBA treatment fell below LOD by day 14, and K-Sorbate reached 2.9 log CFU/g. For E. coli inoculation, with higher concentrations, by day 18, the positive control exceeded 5 log CFU/g. Conversely, LBA treatment greatly decreased and K-Sorbate treatment measured 5.1 log CFU/g. With lower E. coli concentrations, the positive control surpassed 3 log CFU/g, yet LBA treatment dropped below LOD by day 3. Mold counts indicated some inhibition with the K-Sorbate treatment, while control groups showed growth. LBA treatments exhibit noticeable growth inhibition. About the other part of the study, the outcomes demonstrated that while growth of mold occurred in the control group, inhibitory effects were apparent in the treatment groups, and significant distinctions existed between K-Sorbate, nisin, LBA treatments, and the control group. Our findings suggest that LBA has the potential to effectively control the growth of E. coli, S. aureus, and mold in soft cheese. Moreover, LBA displays greater preservative efficacy compared to K-Sorbate and nisin.

Response of Fresh-Cut Iceberg Lettuce to Fumigation with Botanical Essential Oils

Abstract The study was conducted on iceberg lettuce ‘Ice Wave F1’. The effect of prestorage treatment with seven essential oils (EOs) of rosemary, peppermint, basil, thyme, marjoram, lemon, and oregano on the quality of cut lettuce was evaluated. The lettuce was fumigated with EOs for two hours in airtight containers. Two concentrations of EOs were used: 16.7 μL·L−1 and 33.3 μL·L−1. Fumigation with rosemary and thyme EOs lowered the browning of fresh-cut iceberg lettuce and thus the deterioration of its appearance during six days of storage. Lettuce fumigated with thyme EO scored relatively high in sensory quality and consumer acceptability. Lettuce fumigated with rosemary EO was characterized by high intensity of aroma and herbal flavor, significantly lowering its sensory rating. Marjoram EO at a dose of 16.7 μL·L−1 resulted in the fastest browning of lettuce cut surface and relatively reduced the market value during storage. Other EOs had no significant effect on the quality of cut lettuce during shelf life. It was also found that fumigation did not change bacteria, fungi, and mold populations on fresh-cut iceberg lettuce during short-term storage. The results obtained in the study showed that fumigation with thyme oil at a concentration of 33.3 μL·L−1 is most recommended for use in the storage of fresh-cut iceberg lettuce, but implementing these results into practice requires further research.

Effects of different irradiation doses and storage period on microbiological characteristics of wheat (Triticum aestivum L.)

Microbiological analysis of wheat (Triticum aestivum L.) treated with different doses of ionizing radiation (0.2 kGy, 0.5 kGy, 1 kGy, 5 kGy and 10 kGy) is presented in this paper. The aim was to determine the influence of different irradiation doses on the microbial population profile of wheat. In all samples, the total bacterial count and the populations of Enterobacteriaceae, Escherichia coli, Salmonella spp, coagulase-positive Staphylococci, Pseudomonas aeruginosa, Bacillus cereus, Clostridium perfringens, yeasts and molds were examined. The analyses were carried out twice: immediately after irradiation and nine months after treatment. Obtained results revealed the presence of Bacillus cereus, Enterobacteriaceae, yeasts and molds in all examined samples. Salmonella spp, Pseudomonas aeruginosa, Escherichia coli and Clostridium perfringens, were not detected. It has been found that the number of microorganisms decreases with the increase in the irradiation dose, with no viable microorganisms detected at the dose of 10 kGy. In all examined samples, nine months after irradiation, there was a noticeable reduction in the number of microorganisms. Only yeasts and molds were detected at a dose of 5 kGy, while no microbial growth was observed at 10 kGy. There are no reference studies on Enterobacteriaceae inactivation in wheat by ionizing radiation and storage. Therefore this study is the first contribution to understanding this microbial community decrease by gamma radiation after room temperature storage. The results highlighted the prolonged effect of ionizing radiation treatment on the microbiological safety of wheat.

Exploring a novel HE image segmentation technique for glioblastoma: A hybrid slime mould and differential evolution approach

Glioblastoma is a primary brain tumor with high incidence and mortality rates, posing a significant threat to human health. It is crucial to provide necessary diagnostic assistance for its management. Among them, Multi-threshold Image Segmentation (MIS) is considered the most efficient and intuitive method in image processing. In recent years, many scholars have combined different metaheuristic algorithms with MIS to improve the quality of Image Segmentation (IS). Slime Mould Algorithm (SMA) is a metaheuristic approach inspired by the foraging behavior of slime mould populations in nature. In this investigation, we introduce a hybridized variant named BDSMA, aimed at overcoming the inherent limitations of the original algorithm. These limitations encompass inadequate exploitation capacity and a tendency to converge prematurely towards local optima when dealing with complex multidimensional problems. To bolster the algorithm’s optimization prowess, we integrate the original algorithm with a robust exploitative operator called Differential Evolution (DE). Additionally, we introduce a strategy for handling solutions that surpass boundaries. The incorporation of an advanced cooperative mixing model accelerates the convergence of BDSMA, refining its precision and preventing it from becoming trapped in local optima. To substantiate the effectiveness of our proposed approach, we conduct a comprehensive series of comparative experiments involving 30 benchmark functions. The results of these experiments demonstrate the superiority of our method in terms of both convergence speed and precision. Moreover, within this study, we propose a MIS technique. This technique is subsequently employed to conduct experiments on IS at both low and high threshold levels. The effectiveness of the BDSMA-based MIS technique is further showcased through its successful application to the medical image of brain glioblastoma. The evaluation of these experimental outcomes, utilizing image quality metrics, conclusively underscores the exceptional efficacy of the algorithm we have put forth.

Multiprocessor Fair Scheduling Based on an Improved Slime Mold Algorithm

An improved slime mold algorithm (IMSMA) is presented in this paper for a multiprocessor multitask fair scheduling problem, which aims to reduce the average processing time. An initial population strategy based on Bernoulli mapping reverse learning is proposed for the slime mold algorithm. A Cauchy mutation strategy is employed to escape local optima, and the boundary-check mechanism of the slime mold swarm is optimized. The boundary conditions of the slime mold population are transformed into nonlinear, dynamically changing boundaries. This adjustment strengthens the slime mold algorithm’s global search capabilities in early iterations and strengthens its local search capability in later iterations, which accelerates the algorithm’s convergence speed. Two unimodal and two multimodal test functions from the CEC2019 benchmark are chosen for comparative experiments. The experiment results show the algorithm’s robust convergence and its capacity to escape local optima. The improved slime mold algorithm is applied to the multiprocessor fair scheduling problem to reduce the average execution time on each processor. Numerical experiments showed that the IMSMA performs better than other algorithms in terms of precision and convergence effectiveness.

An Enhanced Slime Mould Algorithm Combines Multiple Strategies

In recent years, due to the growing complexity of real-world problems, researchers have been favoring stochastic search algorithms as their preferred method for problem solving. The slime mould algorithm is a high-performance, stochastic search algorithm inspired by the foraging behavior of slime moulds. However, it faces challenges such as low population diversity, high randomness, and susceptibility to falling into local optima. Therefore, this paper presents an enhanced slime mould algorithm that combines multiple strategies, called the ESMA. The incorporation of selective average position and Lévy flights with jumps in the global exploration phase improves the flexibility of the search approach. A dynamic lens learning approach is employed to adjust the position of the optimal slime mould individual, guiding the entire population to move towards the correct position within the given search space. In the updating method, an improved crisscross strategy is adopted to reorganize the slime mould individuals, which makes the search method of the slime mould population more refined. Finally, the performance of the ESMA is evaluated using 40 well-known benchmark functions, including those from CEC2017 and CEC2013 test suites. It is also recognized by Friedman’s test as statistically significant. The analysis of the results on two real-world engineering problems demonstrates that the ESMA presents a substantial advantage in terms of search capability.

Fungal Exposure and Shelter Assessment in Syrian Refugee Settlements in Lebanon

Over 1 million Syrian refugees have fled war to seek asylum in Lebanon. The population has been placed in substandard conditions which could lead to adverse health effects, particularly in vulnerable subgroups, notably due to evident chronic dampness and inadequate ventilation potentially leading to indoor mold growth. To investigate whether the types and conditions of Syrian refugee shelters influence indoor mold populations, a cross-sectional indoor environmental study was performed in 4 provinces of Lebanon. Accordingly, a total of 80 refugee households and 20 host population households (baseline) were selected. Mold air sampling and moisture measurements of shelter material were performed in residential, non-residential, and non-permanent shelters. Results revealed that although non-residential shelters had the highest mean total indoor count (1112 CFU/m3), Aspergillus, Stachybotrys, and Penicillium spp. were strongly associated with non-permanent shelters (p &lt; 0.001). Additionally, occupancy was found to be strongly associated with Cladosporium (p &lt; 0.05), Ulocladium (p &lt; 0.05), and Stachybotrys spp. (p &lt; 0.001). As for shelter conditions, the highest total indoor count (1243 CFU/m3) was reported in unfinished structures. These findings suggest that shelter category, condition and occupancy significantly influence indoor mold concentrations, increasing respiratory health risks for Syrian refugees in Lebanon.

Evaluation of Essential Oils as Additives during Fermentation of Feed Products: A Meta-Analysis

Essential oils (EOs) are secondary metabolites of plants with antimicrobial functions that can be used as silage additives, but their effectiveness has been inconsistent. Therefore, this study aimed to evaluate the effects of EOs as silage additives on nutritional quality, fermentative products, microbial population, and in vitro rumen fermentation. A total of 17 articles consisting of 113 studies (comparisons) were selected for meta-analysis. The results showed that EO supplementation increased several parameters of nutrient contents such as dry matter (DM), crude protein (CP), and ether extract (EE) (p &lt; 0.05), but decreased crude fiber content and mold population (p &lt; 0.05). EO supplementation also affected rumen fermentability, namely reduced gas production, organic matter digestibility, and some fermentation products such as total VFA, iso-butyrate, iso-valerate, acetic, and succinic acid (p &lt; 0.05) but did not affect methane production. Sub-group analysis based on the source of EOs revealed that only cumin and oregano reduced mold population during ensiling (p &lt; 0.05). These results showed that EO supplementation improved several nutrient qualities such as DM, CP, and EE, inhibiting mold growth and stabilizing rumen pH.

Determination of the frequency and virulence of someBotrytis cinereaisolates and a newBotrytis prunorumcryptic species causing grey mould disease on greenhouse tomatoes

AbstractTomato is among the priority crops of greenhouse cultivation in Turkey and in the world. One of the most important fungal diseases of tomatoes is grey mould.Botrytis cinerea,B. cinereagroup S andBotrytis pseudocinereahave been reported previously as causes of grey mould disease on tomatoes. The objectives of this study were to characterize the common grey mould population, their virulence levels, and identify the possible crypticBotrytisspecies occurring on greenhouse tomatoes in Turkey.Botrytisspecies were identified using theRPB2,G3PDH,HSP60andNEP2sequences. The predominant grey mould pathogen wasB. cinerea.B. cinereagroup S andB. pseudocinereawere not isolated. The MH69 isolate was identified asBotrytis prunorum. This is the first time that this cryptic species has been reported causing disease on tomatoes. Differences in the virulence levels ofB. cinereaisolates were observed. The virulence of theB. prunorumisolate was found to be lower than most of theB. cinereaisolates.

A meta-analysis on the influence of essential oils on chemical composition and fermentative quality of silage

Essential oils are plant secondary metabolites that have potential as antimicrobial agents. The use of essential oils as silage additives is expected to maintain feed quality and prevent the growth of spoilage microbes during ensiling. This meta-analysis study aimed to determine the effect of levels of essential oils as silage additives on chemical composition and fermentation quality during ensiling. A total of 11 journal articles consisting of 17 studies and 73 data points were tabulated with related parameters about the chemical composition, fermentation quality, and microbial analysis. The results of the analysis indicate that increasing the levels of essential oils linearly increase (p<0.01) certain chemical compositions, such as crude protein, ether extract, and water-soluble carbohydrate, and simultaneously decrease (p<0.05) the contents of NDF, ADF, ADL, and crude ash. Fermentation products such as lactic acid, acetic acid, and propionic acid decreased (p<0.05) due to the additions of essential oils. Meanwhile, on the microbial parameters, it was found that the use of essential oils was able to reduce the mold population on silage (p<0.01). In conclusion, the addition of essential oils as silage additives maintained nutrient quality, decreased fiber content, and inhibited fungal growth.

Color, pH, microbiological, and sensory quality of crickets (Gryllus bimaculatus) flour preserved with ginger and garlic extracts.

Although spices have been used in food for centuries, little is known about their use to preserve insect-based foods. This study assessed the flour produced from blanched crickets treated with extracts of either ginger, garlic or both at a ratio of 1:4 (v/w) for color, pH, microbiological profile, sensory quality, and acceptability. Sodium benzoate treated and untreated cricket flour was used as positive and negative controls, respectively. The flour was stored at ambient conditions and analyzed on 0, 30, and 60 days of storage. The pH, moisture content and color change increased during storage but remained within acceptable limits. The total microbial count, yeast and molds significantly decreased with storage duration (p˂.05), while fecal coliforms and Escherichia coli were not detected in any of the samples. At the end of the 60-day storage period, cricket flour treated with sodium benzoate and garlic extracts both had a significantly lowest population of yeast and molds (1.91 log cfu/g). On five point hedonic scale (1. Dislike extremely and 5. Like extremely), color (3.84 ± 0.86-2.55 ± 0.99), aroma (3.59 ± 1.09-2.40 ± 1.01), texture (4.11 ± 0.97-3.11 ± 0.97) and overall acceptability (3.77 ± 0.64-2.83 ± 1.01) sensory scores were all significantly high on day 0 and low on day 60 of storage, respectively. The study concluded that preserving crickets with garlic extracts significantly reduced the population of yeast and molds. Cricket flours were microbiologically safe and acceptable to consumers. Therefore, storage of cricket flour preserved with garlic and ginger extracts for longer periods is recommended. In addition, utilization of the preserved flour as an ingredient in different food applications is recommended to determine its suitability and sensory acceptability.

Microbial Load of Fresh Blueberries Harvested by Different Methods.

Currently, more and more growers are transitioning to the use of over-the-row machine harvesters for harvesting fresh market blueberries. This study assessed the microbial load of fresh blueberries harvested by different methods. Samples (n = 336) of 'Draper' and 'Liberty' northern highbush blueberries, which were harvested using a conventional over-the-row machine harvester, a modified machine harvester prototype, ungloved but sanitized hands, and hands wearing sterile gloves were collected from a blueberry farm near Lynden, WA, in the Pacific Northwest at 9 am, 12 noon, and 3 pm on four different harvest days during the 2019 harvest season. Eight replicates of each sample were collected at each sampling point and evaluated for the populations of total aerobes (TA), total yeasts and molds (YM), and total coliforms (TC), as well as for the incidence of fecal coliforms and enterococci. The harvest method was a significant factor (p < 0.05) influencing the TA and TC counts, the harvest time was a significant factor influencing the YM counts, while the blueberry cultivar was an insignificant (p > 0.05) factor for all three indicator microorganisms. These results suggest that effective harvester cleaning methods should be developed to prevent fresh blueberry contamination by microorganisms. This research will likely benefit blueberry and other fresh fruit producers.