Co-Occurrence of Regulated and Emerging Mycotoxins in Corn Silage: Relationships with Fermentation Quality and Bacterial Communities

Sixty-four corn silages were characterized for chemicals, bacterial community, and concentrations of several fungal metabolites. Silages were grouped in five clusters, based on detected mycotoxins, and they were characterized for being contaminated by (1) low levels of Aspergillus- and Penicillium-mycotoxins; (2) low levels of fumonisins and other Fusarium-mycotoxins; (3) high levels of Aspergillus-mycotoxins; (4) high levels of non-regulated Fusarium-mycotoxins; (5) high levels of fumonisins and their metabolites. Altersetin was detected in clusters 1, 3, and 5. Rugulusovin or brevianamide F were detected in several samples, with the highest concentration in cluster 3. Emodin was detected in more than 50.0% of samples of clusters 1, 3 and 5, respectively. Kojic acid occurred mainly in clusters 1 and 2 at very low concentrations. Regarding Fusarium mycotoxins, high occurrences were observed for FB3, FB4, FA1, whereas the average concentrations of FB6 and FA2 were lower than 12.4 µg/kg dry matter. Emerging Fusarium-produced mycotoxins, such as siccanol, moniliformin, equisetin, epiequisetin and bikaverin were detected in the majority of analyzed corn silages. Pestalotin, oxaline, phenopirrozin and questiomycin A were detected at high incidences. Concluding, this work highlighted that corn silages could be contaminated by a high number of regulated and emerging mycotoxins.

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Bacterial Succession Pattern during the Fermentation Process in Whole-Plant Corn Silage Processed in Different Geographical Areas of Northern China

Processes ◽

10.3390/pr9050900 ◽

2021 ◽

Vol 9 (5) ◽

pp. 900

Author(s):

Chao Wang ◽

Hongyan Han ◽

Lin Sun ◽

Na Na ◽

Haiwen Xu ◽

...

Keyword(s):

Acetic Acid ◽

Bacterial Community ◽

Inner Mongolia ◽

Northern China ◽

Ammonia Nitrogen ◽

Corn Silage ◽

Shanxi Province ◽

Whole Plant ◽

Bacterial Succession ◽

Fermentation Quality

Whole-plant corn silage is a predominant forage for livestock that is processed in Heilongjiang province (Daqing city and Longjiang county), Inner Mongolia Autonomous Region (Helin county and Tumet Left Banner) and Shanxi province (Taigu and Shanyin counties) of North China; it was sampled at 0, 5, 14, 45 and 90 days after ensiling. Bacterial community and fermentation quality were analysed. During fermentation, the pH was reduced to below 4.0, lactic acid increased to above 73 g/kg DM (p < 0.05) and Lactobacillus dominated the bacterial community and had a reducing abundance after 14 days. In the final silages, butyric acid was not detected, and the contents of acetic acid and ammonia nitrogen were below 35 g/kg DM and 100 g/kg total nitrogen, respectively. Compared with silages from Heilongjiang and Inner Mongolia, silages from Shanxi contained less Lactobacillus and more Leuconostoc (p < 0.05), and had a separating bacterial community from 14 to 90 days. Lactobacillus was negatively correlated with pH in all the silages (p < 0.05), and positively correlated with lactic and acetic acid in silages from Heilongjiang and Inner Mongolia (p < 0.05). The results show that the final silages had satisfactory fermentation quality. During the ensilage process, silages from Heilongjiang and Inner Mongolia had similar bacterial-succession patterns; the activity of Lactobacillus formed and maintained good fermentation quality in whole-plant corn silage.

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Enzyme additives influence bacterial communities of Medicago sativa silage as determined by Illumina sequencing

10.21203/rs.3.rs-29755/v1 ◽

2020 ◽

Author(s):

Zongfu Hu ◽

Deying Ma ◽

huaxin Niu ◽

Jie Chang ◽

Jianhua Yu ◽

...

Keyword(s):

Lactic Acid ◽

Bacterial Community ◽

High Throughput ◽

Bacterial Communities ◽

Crude Protein ◽

High Throughput Sequencing ◽

Ammonium N ◽

Enzyme Combination ◽

Fermentation Quality ◽

Dominant Bacteria

Abstract This study aimed to evaluate the effects of enzymes (cellulase combined with galactosidase),, and the combination of these enzymes with Lactobacillus plantarum (LP) on bacterial diversity using high-throughput sequencing. Alfalfa forages were treated without or with cellulase + ɑ-galactosidase (CEGA), cellulase + LP (CELP), ɑ-galactosidase + LP (GALP). After 56 days of ensiling, All the treated silages exhibited improved fermentation quality as reflecting by decreased pH, ammonium-N and increased lactic acid levels compared to the control silage. Enzymatic treatment improved nutrients value by increased the level of crude protein and decreased the neutral detergent fibre (NDF) level. Treatment of the silage significantly changed the bacterial community, as determined by the PCoA test. LAB dominated the bacterial community of the treated silage after ensiling. The dominant bacteria from Garciella, Enterococcus, Lactobacillus and Pediococcus in control silage changed to Lactobacillus and Pediococcus in CEGA silage, and Lactobacillus in CELP and GALP silages. Collectively, enzymes and enzyme in combination with inoculants both greatly increased the abundance of LAB, with Enterococcus, Lactobacillus and Pediococcus in enzymes only silge (CEGA) and Lactobacillus in enzyme combination with inoculants silage (CELP and GALP).

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Dynamics of Bacterial Community and Fermentation Quality during Ensiling of Wilted and Unwilted Moringa oleifera Leaf Silage with or without Lactic Acid Bacterial Inoculants

mSphere ◽

10.1128/msphere.00341-19 ◽

2019 ◽

Vol 4 (4) ◽

Cited By ~ 3

Author(s):

Yi Wang ◽

Liwen He ◽

Yaqi Xing ◽

Yanting Zheng ◽

Wei Zhou ◽

...

Keyword(s):

Lactic Acid ◽

Bacterial Community ◽

Dry Matter ◽

Fermentation Process ◽

Moringa Oleifera ◽

Content Type ◽

Bacterial Inoculants ◽

Dry Matter Loss ◽

Fermentation Quality

ABSTRACT To investigate the effects of wilting and lactic acid bacterial inoculants on the fermentation quality and bacterial community of Moringa oleifera leaf silage, fresh and wilted M. oleifera leaves were ensiled with or without Lactobacillus farciminis LF or Lactococcus lactis LL for 1, 7, 14, 30, and 60 days. The results showed that wilting, inoculants, and their interaction exerted significant (P < 0.05) effects on the fermentation characteristics covering dry matter loss, pH value, lactic acid bacterial number, the ratio of lactic acid to acetic acid, and the relative abundances of bacteria, like for species of Lactobacillus, Lactococcus, Pediococcus, Enterococcus, Leuconostoc, and Enterobacter. Both LF and LL improved the fermentation quality of wilted and unwilted M. oleifera leaf silage by accelerating lactic acid production and pH decline, decreasing dry matter loss, and inhibiting yeast and coliform bacterial growth through the whole fermentation process. During ensiling, the abundances of Lactococcus, Enterococcus, and Leuconostoc spp. increased from day 1 to day 7 and then declined sharply from day 7 to day 14. Members of these genera and Enterobacter were inhibited, whereas Lactobacillus spp. were enhanced by these two lactic acid bacterial inoculants. The relative abundances of Enterobacter, Enterococcus, and Pediococcus spp. in inoculated silages were relatively low during the whole ensiling process. A lower abundance of Enterobacter spp. was observed in wilted silages than in unwilted silages. In summary, wilting and lactic acid bacterial inoculants had an influence on bacterial community and the fermentation process; LF and LL improved the fermentation quality of wilted and unwilted M. oleifera leaf silage. IMPORTANCE Moringa oleifera leaf is a high-quality feed source for livestock and is increasingly used all over the world. Ensiling might be an effective method for preservation of the leaves. In the practice of silage making, lactic acid bacterial inoculants and wilting are commonly used to improve nutrition preservation. Monitoring the changes in a bacterial community during fermentation gives an insight into understanding and improving the ensiling process. Our results suggest that wilting and lactic acid bacterial inoculants had an influence on the bacterial community and fermentation process of M. oleifera leaf silage. Wilting showed positive effects on silage fermentation by decreasing the abundance of Enterobacter spp., while LF and LL improved the fermentation quality by inhibiting Enterobacter spp. and enhancing Lactobacillus spp. Both LF and LL accelerated the ensiling process from cocci (like Lactococcus, Enterococcus, and Leuconostoc spp.) to lactobacilli.

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PSII-22 Trends in Mycotoxin Contamination in United States Corn

Journal of Animal Science ◽

10.1093/jas/skaa054.306 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 172-173

Author(s):

Erika Hendel ◽

Shelby Ramirez ◽

Paige Gott ◽

G Raj Murugesan ◽

Ursula Hofstetter

Keyword(s):

Animal Health ◽

Corn Silage ◽

Mitigation Strategies ◽

Fungal Metabolites ◽

Mycotoxin Contamination ◽

Food And Feed ◽

Type A Trichothecenes ◽

Low Levels ◽

Feed Safety ◽

New Crop

Abstract Mycotoxins are harmful secondary fungal metabolites and are of key concern to food and feed safety globally. These toxins are detrimental to animal health and can compromise animal performance even at low levels. Classic signs such as decreased feed intake and vomiting used as indicators for exposure overlook other costs of mycotoxicosis, including increasing the frequency and severity of disease via immune suppression, inciting inflammation, and modulating the gastrointestinal environment. This survey examines initial samples of the 2019 crop with previous year trends. New crop corn samples were submitted from September 2019 and consisted of corn (46%), corn silage (50%), and corn byproduct (4%). Samples were analyzed utilizing the liquid chromatography and tandem mass spectrometry (LC-MS/MS) method for six major mycotoxin groups: aflatoxins (Afla), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin-A (OTA). Data are presented for major mycotoxin classes in Table 1. Fewer samples are available thus far compared to the fall of 2018 (50 samples in 2019 vs. 135 samples in 2018), thus risk profile of this crop year is likely to change as the sample pool expands. Co-occurrence (≥ 2 mycotoxins) has decreased compared to 2018. The prevalence of B-Trich decreased compared with previous years, but levels are similar to 2018. Prevalence and levels of ZEN decreased from 2018, and are similar to 2017, while FUM is similar in prevalence to 2018, but average ppb numerically increased. As of yet, no Alfa has been detected; however, corn stored with higher moisture content has increased the risk for storage toxins. Mycotoxin risk of this harvest season is still coming into focus as harvest delays have affected sample submission. Due to continued risk of multi-mycotoxin contamination, multiple mitigation strategies are needed beyond just adsorption, including biotransformation, support of the immune system and liver function.

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Lentilactobacillus hilgardii Inoculum, Dry Matter Contents at Harvest and Length of Conservation Affect Fermentation Characteristics and Aerobic Stability of Corn Silage

Frontiers in Microbiology ◽

10.3389/fmicb.2021.675563 ◽

2021 ◽

Vol 12 ◽

Author(s):

Francesco Ferrero ◽

Ernesto Tabacco ◽

Giorgio Borreani

Keyword(s):

Acetic Acid ◽

Dry Matter ◽

Corn Silage ◽

Microbial Count ◽

Dependent Manner ◽

Aerobic Stability ◽

Fermentation Quality ◽

Silage Quality ◽

Silage Inoculant ◽

Positive Effect

Heterofermentative Lentilactobacillus hilgardii isolated from sugarcane silage, has recently been proposed as a silage inoculant to increase aerobic stability. Various conditions can influence the activity of LAB and their ability to alter silage quality (e.g., DM content and length of conservation). The aim of this study has been to evaluate the effect of L. hilgardii on the fermentation quality and aerobic stability of whole crop corn silage with different DM contents (from 26 to 45%), conserved for various conservation lengths (13–272 days). The silages were analyzed for their DM content, pH, fermentative profile, microbial count, and aerobic stability. L. hilgardii showed a positive effect on improving the aerobic stability of silages, due its ability to produce acetic acid, and reduced the yeast count. The acetic acid content increased as the conservation period increased and decreased as the DM content increased. The yeast count was reduced during conservation in a DM dependent manner and the inoculation with LH determined a reduction in the count of 0.48 log cfu/g. The aerobic stability increased as the conservation period increased, and the treatment with LH on average increased the aerobic stability by 19 h. The results of this experiment suggest that higher aerobic stability could be achieved in corn silages by ensiling at medium or low DM contents, or by increasing the length of conservation if a higher DM content at ensiling is needed. The inoculation with LH helps to improve the aerobic stability of corn silages by reducing the yeast count.

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Dynamics of the Fermentation Products, Residual Non-structural Carbohydrates, and Bacterial Communities of Wilted and Non-wilted Alfalfa Silage With and Without Lactobacillus plantarum Inoculation

Frontiers in Microbiology ◽

10.3389/fmicb.2021.824229 ◽

2022 ◽

Vol 12 ◽

Author(s):

Fengyuan Yang ◽

Yanping Wang ◽

Shanshan Zhao ◽

Changsong Feng ◽

Xiaomiao Fan

Keyword(s):

Bacterial Community ◽

Lactobacillus Plantarum ◽

Bacterial Communities ◽

High Throughput Sequencing ◽

Bacterial Community Composition ◽

Water Soluble ◽

Soluble Carbohydrates ◽

Fermentation Products ◽

Fermentation Quality ◽

Alfalfa Silage

The aim of this study was to investigate effects of wilting and Lactobacillus plantarum inoculation on the dynamics of the fermentation products, residual non-structural carbohydrates, and bacterial communities in alfalfa silage. Fresh and wilted alfalfa were ensiled with and without L. plantarum for 10, 30, 60, and 90 days. A high-throughput sequencing method for absolute quantification of 16S rRNA was adopted to determine the bacterial community composition at different ensiling periods. For the wilted silage, the bacterial community, pH value, and ammonia nitrogen concentration remained stable in the silage at 30 days. L. plantarum inoculation accelerated lactic acid fermentation and altered the predominant genus in the wilted silage as compared with the non-inoculated group. For the non-wilted group, fast consumption of water-soluble carbohydrates (WSCs) was observed at 10 days in the non-inoculated silage along with rapid growth of undesirable Hafnia. L. plantarum inoculation inhibited growth of Hafnia at 10 days in the non-wilted silage. Clostridia fermentation occurred in the non-wilted silage at 90 days, as indicated by an increased pH, formation of butyric acid (BA), and apparent abundance of genera belonging to Clostridia. L. plantarum inoculation inhibited BA accumulation and growth of Garciella in the non-wilted silage at 90 days as compared with the non-wilted silage without inoculation, but had little effect on the growth of Clostridium sensu stricto. Overall, the high moisture content of the non-wilted alfalfa silage led to rapid consumption of WSCs and growth of harmful microorganisms at the early stage of ensiling, resulting in poor fermentation quality. Wilting and L. plantarum inoculation both improved fermentation quality and inhibited the growth of spoilage microorganisms in alfalfa silage, while L. plantarum inoculation alone failed to achieve optimum fermentation quality of non-wilted alfalfa silage.

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Effect of Ellagic Acid on Fermentation Quality and Bacterial Community of Stylo Silage

Fermentation ◽

10.3390/fermentation7040256 ◽

2021 ◽

Vol 7 (4) ◽

pp. 256

Author(s):

Xuan Zou ◽

Dandan Chen ◽

Hongjian Lv ◽

Qing Zhang ◽

Peng Zheng

Keyword(s):

Bacterial Community ◽

Ellagic Acid ◽

Crude Protein ◽

Dry Matter ◽

Ph Value ◽

Ammonium Nitrogen ◽

Coliform Bacteria ◽

Fresh Matter ◽

Fermentation Quality ◽

Matter Basis

This study was conducted to investigate the effect of ellagic acid on the bacterial community and fermentability of stylo silage. Three treatments of stylo silage were used: control (CK) and treated with 1% or 2% ellagic acid (EA1 and EA2) on a fresh matter basis. All silage was stored at ambient temperature and opened on days 3, 7, 14, and 30. Fermentation characteristics, protein fraction, and bacteria community of all periods of silage were analyzed. Results showed that dry matter and crude protein content were increased, and pH value, number of coliform bacteria, contents of acetic acid, and ammonium nitrogen were decreased with the addition of ellagic acid. The antioxidant activity of 1% and 2% ellagic acid treated silages was significantly higher than the control. Meanwhile, the relative abundance of Klebsiella and Clostridium was decreased with the addition of ellagic acid, and the abundance of Lactobacillus, Weissella, and Enterococcus was increased with prolonged days of ensiling. Adding ellagic acid to stylo silage could improve the fermentation quality and preservation of protein, and reduce the abundance of harmful bacteria.

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Multiple Fungal Metabolites Including Mycotoxins in Naturally Infected and Fusarium-Inoculated Wheat Samples

Microorganisms ◽

10.3390/microorganisms8040578 ◽

2020 ◽

Vol 8 (4) ◽

pp. 578 ◽

Cited By ~ 4

Author(s):

Valentina Spanic ◽

Zorana Katanic ◽

Michael Sulyok ◽

Rudolf Krska ◽

Katalin Puskas ◽

...

Keyword(s):

Kojic Acid ◽

Fumonisin B1 ◽

Fungal Metabolites ◽

Tenuazonic Acid ◽

Fusarium Mycotoxins ◽

Flowering Stage ◽

Wheat Varieties ◽

Worst Case ◽

Alternaria Mycotoxins ◽

Fumonisin B2

In this study, the occurrence of multiple fungal metabolites including mycotoxins was determined in four different winter wheat varieties in a field experiment in Croatia. One group was naturally infected, while the second group was inoculated with a Fusarium graminearum and F. culmorum mixture to simulate a worst-case infection scenario. Data on the multiple fungal metabolites including mycotoxins were acquired with liquid chromatography with mass spectrometry (LC-MS/MS) multi-(myco)toxin method. In total, 36 different fungal metabolites were quantified in this study: the Fusarium mycotoxins deoxynivalenol (DON), DON-3-glucoside (D3G), 3-acetyldeoxynivalenol (3-ADON), culmorin (CULM), 15-hydroxyculmorin, 5-hydroxyculmorin, aurofusarin, rubrofusarin, enniatin (Enn) A, Enn A1, Enn B, Enn B1, Enn B2, Enn B3, fumonisin B1, fumonisin B2, chrysogin, zearalenone (ZEN), moniliformin (MON), nivalenol (NIV), siccanol, equisetin, beauvericin (BEA), and antibiotic Y; the Alternaria mycotoxins alternariol, alternariolmethylether, altersetin, infectopyron, tentoxin, tenuazonic acid; the Aspergillus mycotoxin kojic acid; unspecific metabolites butenolid, brevianamid F, cyclo(L-Pro-L-Tyr), cyclo(L-Pro-L-Val), and tryptophol. The most abundant mycotoxins in the inoculated and naturally contaminated samples, respectively, were found to occur at the following average concentrations: DON (19,122/1504 µg/kg), CULM (6109/1010 µg/kg), 15-hydroxyculmorin (56,022/1301 µg/kg), 5-hydroxyculmorin (21,219/863 µg/kg), aurofusarin (43,496/1266 µg/kg). Compared to naturally-infected samples, Fusarium inoculations at the flowering stage increased the concentrations of all Fusarium mycotoxins, except enniatins and siccanol in Ficko, the Aspergillus metabolite kojic acid, the Alternaria mycotoxin altersetin, and unspecific metabolites brevianamid F, butenolid, cyclo(L-Pro-L-Tyr), and cyclo(L-Pro-L-Val). In contrast to these findings, because of possible antagonistic actions, Fusarium inoculation decreased the concentrations of the Alternaria toxins alternariol, alternariolmethylether, infectopyron, tentoxin, tenuazonic acid, as well as the concentration of the nonspecific metabolite tryptophol.

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Enzyme additives influence bacterial communities of Medicago sativa silage as determined by Illumina sequencing

AMB Express ◽

10.1186/s13568-020-01158-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zongfu Hu ◽

Deying Ma ◽

Huaxin Niu ◽

Jie Chang ◽

Jianhua Yu ◽

...

Keyword(s):

Lactic Acid ◽

Bacterial Community ◽

Bacterial Communities ◽

Crude Protein ◽

High Throughput Sequencing ◽

Protein Levels ◽

Nutrient Value ◽

Ammonium N ◽

Fermentation Quality ◽

Dominant Bacteria

AbstractThe goal of the present study was to evaluate the effects of enzymes (cellulase combined with galactosidase) and their combination with Lactobacillus plantarum (LP) on bacterial diversity in alfalfa silages using high-throughput sequencing. Alfalfa forages were treated with or without cellulase + ɑ-galactosidase (CEGA), cellulase + LP (CELP), or ɑ-galactosidase + LP (GALP). After 56 days of ensiling, all treated silages exhibited improved fermentation quality, as reflected by decreased pH, ammonium-N and increased lactic acid levels compared to the control silage (P < 0.05). Enzymatic treatment improved nutrient value by increasing crude protein levels and decreasing neutral detergent fibre (NDF) levels (P < 0.05). Silage treatment significantly altered the bacterial community, as determined by PCoA (P < 0.05). Lactic acid bacteria (LAB) dominated the bacterial community of the treated silage after ensiling. The dominant bacteria changed from Garciella, Enterococcus, Lactobacillus and Pediococcus in the control silage to Lactobacillus and Pediococcus in the CEGA silage and Lactobacillus in the CELP and GALP silages. Collectively, these results suggest that treatment with both enzymes alone and in combination with inoculants greatly increased the abundance of LAB, with Enterococcus, Lactobacillus and Pediococcus observed in the silage treated with enzymes alone (CEGA) and Lactobacillus observed in the silage treated with a combination of enzymes and inoculants (CELP and GALP).

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Enzyme additives influence bacterial communities of Medicago sativa silage as determined by Illumina sequencing

10.21203/rs.3.rs-29755/v2 ◽

2020 ◽

Author(s):

Zongfu hu ◽

Deying Ma ◽

Huaxin Niu ◽

Jie Chang ◽

Jianhua Yu ◽

...

Keyword(s):

Lactic Acid ◽

Bacterial Community ◽

High Throughput ◽

Bacterial Communities ◽

Crude Protein ◽

High Throughput Sequencing ◽

Nutrient Value ◽

Ammonium N ◽

Fermentation Quality ◽

Dominant Bacteria

Abstract This study aimed to evaluate the effects of enzymes (cellulase combined with galactosidase), and the combination of these enzymes with Lactobacillus plantarum (LP) on bacterial diversity using high-throughput sequencing. Alfalfa forages were treated with or without cellulase + ɑ-galactosidase (CEGA), cellulase + LP (CELP), or ɑ-galactosidase + LP (GALP). After 56 days of ensiling, all the treated silages exhibited improved fermentation quality, as reflected by decreased pH, ammonium-N and increased lactic acid levels compared to the control silage. Enzymatic treatment improved nutrient value by increasing the level of crude protein and decreasing the neutral detergent fibre (NDF) level. Treatment of the silage significantly changed the bacterial community, as determined by the PCoA test. LAB dominated the bacterial community of the treated silage after ensiling. The dominant bacteria from Garciella, Enterococcus, Lactobacillus and Pediococcus in the control silage changed to Lactobacillus and Pediococcus in the CEGA silage, and Lactobacillus in the CELP and GALP silages. Collectively, enzymes and enzymes in combination with inoculants both greatly increased the abundance of LAB, with Enterococcus, Lactobacillus and Pediococcus in the silage with enzymes only (CEGA) and Lactobacillus in the silage with a combination of enzymes and inoculants (CELP and GALP).

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