Water-soluble Carbohydrates Research Articles

Interaction between plants and epiphytic lactic acid bacteria that affect plant silage fermentation.

Lactic acid bacteria (LAB) have the ability to ferment water-soluble carbohydrates, resulting in the production of significant amounts of lactic acid. When utilized as additives in silage fermentation and feed, they have been shown to enhance the quality of these products. Epiphytic LAB of plants play a major role in the fermentation of silage plants. Plant species in turn affect the community structure of epiphytic LAB. In recent years, an increasing number of studies have suggested that epiphytic LAB are more effective than exogenous LAB when applied to silage. Inoculating silage plants with epiphytic LAB has attracted extensive attention because of the potential to improve the fermentation quality of silages. This review discusses the interaction of epiphytic LAB with plants during silage fermentation and compares the effects of exogenous and epiphytic LAB on plant fermentation. Overall, this review provides insight into the potential benefits of using epiphytic LAB as an inoculant and proposes a theoretical basis for improving silage quality.

A comparison of the nutritive value of perennial ryegrass, perennial ryegrass and white clover and multispecies‐based farmlet systems

AbstractBackgroundLimited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.MethodsThree farmlet types were investigated in terms of their nutritive value: Lolium perenne (LP); L. perenne+Trifolium repens (LP+TR); and a multispecies sward containing grasses, legumes and herbs (MSS). Farmlets were stocked with beef steers (2.5 livestock units ha−1), grazed on a 1 ha scale to 6 cm (MSS) and 4 cm (LP and LP+TR) residuals.ResultsA greater ash concentration was found in MSS than LP (84 vs. 75 g kg−1 DM). Both LP+TR and MSS had higher crude protein and lower neutral detergent fibre concentrations than LP. The relative ranking of water soluble carbohydrate and dry matter (DM) concentration was LP > LP+TR > MSS. Despite the leaf component of the LP farmlet contributing more to herbage DM, the organic matter digestibilities of the swards were similar.ConclusionsThe MSS and LP+TR farmlets achieved similar forage quality under intensive grazing to LP. However, it is worth noting that MSS had a higher concentration of acid detergent lignin, which can negatively impact digestibility. Further investigation is needed to determine optimal grazing management practices that can minimise the effects of higher lignin concentration on digestibility in multispecies swards.

Effects of cut height and inoculant application on yield, nutrient composition, fermentative profile, and in vitro degradability of brown midrib whole-plant corn silage

Our objective was to determine the effects of cut height and inoculant application on brown midrib (BMR) whole-plant corn silage (WPCS) quality. Corn was harvested at 2 cut heights: low-cut height (LC, 30.5 cm) and high-cut height (HC, 56 cm). Three commercially available inoc- ulants were used as treatments: Lactobacillus plantarum and Pediococcus pentosaceus (SA), Propionibacteria freud- enreichii and Pediococcus pentosaceus (P2), and Lactoba- cillus buchneri and Pediococcus pentosaceus (B500). Mini silos were opened at 5 fermentation time points: 0, 2, 5, 30, and 90 d. Gross yield and DM yield of BMR WPCS decreased for HC compared with LC. The HC increased the concentrations of BMR WPCS DM, CP, and starch and predicted milk yield; decreased the concentration of NDF and ADF; and tended to increase NDF digestibility in 30-h in vitro digestion. The greater nutritive value of the HC possibly allows for an increased quantity of forage to be included in the TMR and de- creases the amount of ground corn needed to be added to the diet, potentially providing an economic benefit. The HC had lower acetic acid concentration compared with LC for CON and B500. The HC tended to have lower total acids and lactic acid compared with LC for all treatments. There was an interaction of height × length of storage for the fermentative profile. The increased acid concentra- tions during ensiling were expected and the greater acids concentration for LC compared with HC was probably due to more water-soluble carbohydrates for LC, which should have improved fermentation. The HC yielded a WPCS with better nutritional value; however, the fermen- tative profile was reduced compared with LC. Our results indicate that in the present conditions, the use of these particular inoculants did not improve WPCS fermentation profile.

Organic waste recycling by vermicomposting amended with rock phosphate impacts the stability and maturity indices of vermicompost

ABSTRACT Recycling organic waste can help the land be nourished, properly disposed of, and protected from the negative impacts of chemical fertilizers. Organic additions like vermicompost can help restore and preserve the quality of the soil, however, producing vermicompost of a high enough standard is difficult. This study was planned to prepare vermicompost by utilizing two different organic wastes viz. household waste and organic residue amended with rock phosphate and further evaluate their stability and maturity indices during vermicomposting for quality of produce. For this study, the organic wastes were collected and vermicompost was prepared by using earthworm (Eisenia fetida) and with or without enriching with rock phosphate. Results showed that pH, bulk density, and biodegradability index were decreased and water holding capacity and cation exchange capacity was increased with the gradual progress of composting starting from 30 to 120 days of sampling/composting (DAS). Initially (upto 30 DAS) water-soluble carbon and water-soluble carbohydrate increased with rock phosphate enrichment. The population of the earthworms and enzymatic activities (CO2 evolution, dehydrogenase, and alkaline phosphatase) were also increased on enriching with rock phosphate and with the progression of the composting period. Rock phosphate addition (enrichment) also reflected the higher content of phosphorus (106% and 120% for household waste and organic residue, respectively) in the final product of vermicompost. The vermicompost prepared from household waste and enriched with rock phosphate showed greater maturity and stability indices. Overall, this can be concluded that the maturity and stability of vermicompost depend on the substrate used and improves on enriching with rock phosphate. Implications: Our study concludes that the quality of vermicompost depends on different substrates, composting period, and enrichment with rock phosphate. The qualities of vermicompost were best found under household waste-based vermicompost enriched with rock phosphate. The efficiency of vermicomposting process using earthworms was found maximum for enriched and without enriched household-based vermicompost. The study also indicated that several stability and maturity indices are influenced by different parameters and hence cannot be determined by a single parameter. The addition of rock phosphate increased the cation exchange capacity, phosphorus content, and alkaline phosphatase. Nitrogen, zinc, manganese, dehydrogenase, and alkaline phosphatase were found higher under household waste-based vermicompost relative to organic residue-based vermicompost. All four substrates promoted earthworm growth and reproduction in vermicompost.

Effects of cellulase and xylanase on fermentative profile, bacterial diversity, and in vitro degradation of mixed silage of agro-residue and alfalfa

The objective was to determine effects of cellulase, xylanase, and commercial fibrolytic enzymes on fermentation quality, aerobic stability, bacterial community, and in vitro degradation of mixed silages. Mixtures of alfalfa, wheat bran, and rice straw [80:15:5 on a fresh matter (FM) basis] were ensiled for 1, 3, 5, 7, 15, 30, and 45 d after treatment with: distilled water (control, C); cellulase (E); xylanase (X); or commercial fibrolytic enzymes (EX), with all enzyme preparations applied at 100 U/g FM. The 45-day silages were subjected to an in vitro degradation test. Each of the three enzyme-treated groups enriched relative abundance (RA) of Lactobacillus, Weissella, and Stenotrophomonas maltophilia, increased water soluble carbohydrate (WSC) concentrations, and extended aerobic stability over 384 h, but concurrently inhibited growth of undesirable microbes (i.e., Acinetobacter sp, Lelliottia amnigena, and Sphingomonas sp), reducing pH and concentrations of ammonia nitrogen (AN), butyric acid (BA) and propionic acid (PA). Compared to C, adding X or EX increased the RA of L. paralimentarius and L. parabrevis, enhanced accumulation of acetic acid (AA) and crude protein (CP), and reduced hemicellulose content. Furthermore, E group silage had the highest abundance of W. cibaria. In addition, EX enriched RA of Bacillus velezensis, reduced AN concentration, increased DM degradability, total VFA production, and gas production during in vitro incubation. In conclusion, addition of X or EX enhanced ensiling by enhancing concentrations of AA; however, EX was the most promising enzyme, based on reducing AN concentration and increasing DM content and DM degradability.Graphical

The Effect of Lactobacillus planturum YQM48 Inoculation on the Quality and Microbial Community Structure of Alfalfa Silage Cultured in Saline-Alkali Soil

Alfalfa cultivated in salt–alkali soil was used for fermentation, to which an inoculum of Lactobacillus plantarum YQM48 was added, to assess its effect on the feed quality and the microbial community structure of the fermented silage. A control was included without inoculum. The nutritional components, fermentation quality, pH, and microbial community of the silage were measured after 30 and 60 days of anaerobic fermentation. The results showed that after 30 and 60 days of fermentation in the presence of the inoculum, the content of water-soluble carbohydrates, crude protein content, and dry matter were all significantly higher than those of the control silage, the pH and butyric acid content were lower, and the content of lactic acid and acetic acid were higher (p < 0.05 for all). There was no significant difference in pH and butyric acid content between 30 and 60 days of fermentation in the presence of the inoculum (p > 0.05), while the lactic acid and acetic acid contents were significantly lower in the 60-day silage compared to the 30-day silage (p < 0.05). Fermentation reduced the abundance of Cyanobacteria and Proteobacteria (the abundant phyla in the fresh alfalfa), while the abundance of Firmicutes increased, reaching 92.3% after 60 days of fermentation with inoculum. The dominant genus in that sample was Lactobacillus (70.0%), followed by Enterococcus (12.9%), while fermentation of 60 days without inoculum resulted in only 29.2% Lactobacillus, together with 27.8% Cyanobacteria, and 12.2% Enterococcus. In summary, the addition of L. plantarum YQM48 can improve the nutritional components and fermentation quality of alfalfa silage cultivated on a salt-alkali soil.

Interspecific interactions between crops influence soil functional groups and networks in a maize/soybean intercropping system

Despite increasing evidence that intercropping systems may increase crop productivity, little is known about whether and how soil biota change under interspecific competition among plants. A field experiment with maize/soybean intercropping and the corresponding monoculture systems was conducted under four nitrogen fertilization regimes to investigate the effects of interspecific plant interactions on grain yield, soil properties (β-glucosidase and water-soluble carbohydrates), and biotic communities (bacteria, fungi, and nematodes). The soils under maize and soybean in the intercropping system were sampled separately to represent intercropped maize and intercropped soybean, respectively. Compared to monocultures, the complexity and robustness of soil networks comprising bacterial, fungal, and nematode communities increased in intercropped maize soils, but densities of plant parasitic nematodes and β-glucosidase activity were reduced. Intercropped soybean soils had lower C availability due to chronic shading by maize, but a significant increase was found in saprophytic fungi, and plant parasitic nematodes compared to soybean monoculture soils. Although intercropped soybean suffered from interspecific competition with maize, the interactions within the fungal community increased for both crop species in the intercropping system. Our study demonstrates that increased carbon uptake in maize due to increased light capture in the intercropping system can facilitate nutrient cycling by altering the abundance of functional groups of soil organisms, such as saprophytic fungi, and enhancing network complexity and stability. We detected a trade-off between productivity and soil nematode diversity in the intercropping system under nitrogen fertilization, the yield of maize increased but soil nematode richness decreased at low nitrogen level, while the yield of soybean decreased but the nematode richness increased at high nitrogen level. These findings show that both trade-offs and benefits occur in intercropping systems and highlight the role of plant-soil biota interactions in such systems.

Long transportation duration affects nutrient composition, mycotoxins and microbial community in whole-plant corn silage.

Potential nutrient losses and mycotoxin accumulation caused by abnormal fermentation during transportation from cropland to dairy farms leads to the diseases incidence and threatens the health of dairy cows, then further causes financial losses. The aim of this study was to investigate the effects of different transportation times on the nutritional composition, mycotoxins, and microbial communities in whole-plant corn silage (WPCS). Three groups were subjected to different transport times: DY, short (<200 min); ZY, medium time (300-500 min); and CY, long transport time (>600 min). WPCS were collected from the same field, and nutrient composition and microbial composition before and after transportation were analyzed. Our results showed that the temperature of WPCS was higher in the ZY and CY groups than in the DY group (P < 0.01). There were no significant differences in dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE) and starch contents after different transportation times (P > 0.05), whereas the starch and water-soluble carbohydrates (WSC) contents in the CY group was significantly decreased after transport (P < 0.05). Similarly, the concentration of vomitoxin in the DY and CY groups declined markedly (P < 0.05) and the zearalenone content in the DY group also significantly decreased after transportation (P < 0.05). Regarding the analysis of microorganisms in WPCS, UniFrac-distance matrices and Shannon indices showed differences in the ZY group (P < 0.05), but fungal diversities were not influenced by the transport time (P > 0.05). In the ZY group, the relative abundance of Lactiplantibacillus decreased significantly after transportation (P > 0.05), but the relative abundances of unidentified_Chloroplast, Pantoea, Gluconobacter, unidentified Acetobacter and Acinetobacter increased markedly (P < 0.05). In addition, the relative abundances of Acetobacter and Gluconobacter in the CY group increased after transport (P < 0.05). Among fungal communities, a total of three, nine, and ten different fungal flora were observed in the DY, ZY, and CY groups, respectively, although no difference was found in fungal diversity. In conclusion, increased temperature, loss of starch, and mycotoxin variation were found with increased transport time. This might be the result of competition between bacteria and fungi, and novel technologies will need to be utilized for further exploration of the mechanism.

Minimally invasive evaluation of cellulose paper degradation using water-soluble carbohydrates

Minimally invasive evaluation of cellulose paper degradation using water-soluble carbohydrates

50 Water-soluble carbohydrate content in equine pasture: Impact of fertilization, season, and grass species

Horses spend a significant proportion of time grazing to meet their nutritional requirements. However, many domesticated horses now graze on energy-dense pastures designed to support production animals. Excessive consumption of these pastures that often contain significant quantities of water-soluble carbohydrates (WSC) has been linked to the development of pasture-associated laminitis. Although seasonal changes in pasture WSC content are well documented, the impact of fertilization or grass species composition are less defined. To evaluate the effect of season and fertilization on WSC concentrations, grassland plots were established at SRUC Aberdeen, UK. Six distinct cool-season seed mixtures (Table 1) were sown in triplicate plots (3m x 4m) and split in half to evaluate the effect of fertilizer treatment (285kg/ha of 21–8-11, annual application in March). Samples were collected on ice at set 6-to-8-week intervals (May–October) across 2 consecutive years. The Anthrone method was employed to estimate WSC content of lyophilised and milled samples, expressed as glucose and fructose equivalents [g/kg DM]. Independent t-test analysis (significance set at P < 0.05) revealed that fertilization had no overall effect on the WSC fraction for glucose (t(94) = 1.02, P = 0.99, 95% CI [-7.57, 23.51]) or fructose (t(94) = 1.28, P = 0.78, 95% CI [-4.69, 21.85]). Analysis of variance analysis demonstrated a significant effect of seed mixture (F = 2.56, P = 0.033 for glucose, F = 2.39, P = 0.044 for fructose) and season (glucose: F = 21.88, P = < 0.001, fructose:F = 21.09, P = < 0.001). WSC concentration was highest in samples collected in Spring, while the perennial rye grass mix (5) and a diverse herb mix (4) had the highest and lowest WSC contents across all samples, respectively. These preliminary results suggest that season and grass species composition have a greater effect on WSC concentrations in pasture than fertilizer treatment. Further studies are warranted to estimate the impact of fertilizer on other aspects of grass chemical composition that may have implications for managing pasture for grazing animals.

112 Effects of storage-handling methods on nutrient analysis of mixed-grass pasture samples

Forage should be the basis of any equine diet, even for those with insulin dysregulation (ID). Fresh and preserved forage low in nonstructural carbohydrates (NSC) is recommended for ID animals, indicating the need for an accurate forage analysis. It remains to be fully understood how handling fresh forage samples pre-analysis impacts nutrient values. The objectives of this study were to compare 5 pasture sample storage-handling methods, analyzed after 24h and 1wk, on various nutrients including crude protein (CP), water soluble carbohydrates (WSC), ethanol soluble carbohydrates (ESC), starch and NSC. In October 2022, forage samples were manually harvested to ground height between 0800 and 0900 from a mixed-grass pasture after a rest period. Subsamples were mixed to create triplicate samples for analysis at both time periods (24h vs 1 wk) and the following 5 storage-handling methods: microwave-oven (70s then stored at −20°C; MO), room temperature (RT), 3°C, −20°C, and −80°C, totaling 30 samples. All forage samples were shipped on ice to a commercial laboratory for wet chemistry and NIR analysis (Equi-Analytical, Ithaca, NY). Data were analyzed using 2-way ANOVAs in JMP with fixed effects of storage method, time and storage by time interactions as well as storage-handling method by laboratory analysis method and method by storage interactions.Statistical significance was declared at P ≤ 0.05. All data reported are from wet chemistry analysis as there were no significant differences between the 2 analysis techniques. Storage by time interactions were statistically different for some nutrients measured from the mixed grass when stored at RT. Specifically, the WSC (9.2 ± 0.4% DM vs. 5.4 ± 0.9% DM; P = 0.009) and ESC (5.4 ± 0.4% DM vs. 3.6 ± 0.6% DM; P = 0.001) content decreased from 24h compared with 1wk. The remaining storage-handling methods of MO, 3°C, −20°C, and −80°C, however, showed no statistical differences across time for WSC, Starch or NSC indicating these methods were appropriate for storing forage for this time. A decrease in CP content from 24h compared with 1wk was, however, shown when stored at −80°C (12.7 ± 0.6% DM vs. 11.2 ± 0.3% DM; P = 0.02), yet no other statistical differences in CP were detected. These results demonstrate that samples kept at RT or −80°C for one week before nutrient analysis may not accurately represent the nutrient content of the forage. Storage-handling method and time did affect the nutrient content of fresh forage thus, samples should be either immediately dried, kept at 3°C, or frozen (−20°C) preceding analysis.

182 Feed intake and metabolic responses in horses in transition from haylage feeding to pasture grazing

The transition from winter-feeding to pasture involves a considerable diet change that might compromise health of horses, and info on the metabolic responses in horses on pasture are scarce. The objective of the study was to investigate how the transition from haylage feeding to strip grazing affected feed intake (FI) and metabolic responses (blood glucose (GLU)-insulin (INS) and cecal pH). Four cecum-cannulated Norwegian cold-blooded trotter geldings were used in a longitudinal study consisting of 3 periods: 1) haylage only (d 0 to 8) reflecting winter-feeding, 2) transition (d 9 to 20) reflecting a diet where the proportion of forage decreased and grazing increased (0 min to 2 × 3 h per d), and 3) grazing only (d 21 to 28) reflecting horses on pasture (2 × 3 h per d). Strip grazing was used to control and measure daily FI in period 2 and 3. From d 9 to 28 the horses were allowed access to a new strip of grass for a specified time-period. The remaining grass was cut each day after grazing, collected, weighed, and compared with the amount of grass from a strip of ungrazed pasture. It was possible to estimate FI for all horses and calculate an average FI per horse. Haylage and grass samples from every 4th d were analyzed for nutritional composition (neutral detergent fiber excluding residual ash (aNDFom), water soluble carbohydrates (WSC), and crude protein (CP)) and used to estimate dry matter (DM) and nutrientintake. On d 8 and 28, blood and cecal samples were collected before and each h after feeding (2 kg haylage as fed vs. 3 h of grazing) for 8 h. ?Area under the curve (AUC) of GLU and INS were calculated using GraphPad Prism. The effect of d on nutrient content, FI, body weight (BW), AUC and peak GLU and INS, and minimum pH were compared using PROC mixed in SAS and considered different if P < 0.05. Grass yield increased (P < 0.001) over time as the grass matured (0.32 to 0.54 kg DM/m2). Plant maturity of the grass affected the nutrient content (P < 0.001) as aNDFom increased (545 to 636 g/kg DM), and CP decreased (158 to 101 g/kg DM). The WSC content varied (P < 0.001) over time (73 to 128 g/kg DM). Similar BW was measured on d 8 and 28 (568 ± 31 kg). The DM intake was 1.62 kg (0.29% of BW) on d 8 and estimated to be 3.7 kg (0.65% of BW) on d 28. There was no effect of d on AUC and peak GLU and INS, but cecal pH was higher (P < 0.001) when feeding haylage (6.89) on d 8 than pasture (6.57) on d 28. In conclusion, FI was controlled by strip grazing, BW was maintained, and metabolic responses were within the expected ranges. However, a longer grazing time would probably result in increased FI and undesired BW gain.

Leaf, Root, and Crown Tissue Physiology of Annual Bluegrass after Cold Acclimation at Varying Soil Moisture Levels and Ice Encasement

Annual bluegrass (Poa annua) is a turfgrass species prone to winterkill-induced damage such as from ice encasement stress. This research aimed to determine whether different levels of soil volumetric water content (SWC) influence cold acclimation and recovery from ice encasement. Annual bluegrass was exposed to 8%, 12%, and 20% SWC treatments during cold acclimation in growth chambers. After cold acclimation, plants were subjected to ice encasement by misting at –3 °C until a 2.5-cm ice layer was formed. On 0 (no ice encasement exposure), 40, and 80 days of treatment, plants were analyzed for recovery (percent green canopy cover over time), and leaf, crown, and root tissues were harvested for lipid peroxidation and total nonstructural carbohydrates (TNC) including storage carbohydrates and water-soluble carbohydrates (WSC). Low SWC during cold acclimation enhanced recovery from cold temperatures and ice encasement. Root carbohydrates were influenced by SWC regimes during cold acclimation since day 0 plant roots exposed to the 8% SWC treatment had 143.9% higher TNC and 137.6% higher WSC compared with day 0 plants exposed to 12% and 20% SWC. Root levels of carbohydrates and lipid peroxidation were least influenced by cold and ice encasement among the organs evaluated. Prolonged freezing conditions and ice encasement reduced leaf and crown tissue carbohydrates and increased lipid peroxidation compared with day 0 plants not exposed to freezing temperatures and ice encasement. After 40 days of ice encasement, plants exposed to the 8% SWC treatment recovered faster than plants cold acclimated at higher soil moisture levels. Average percent canopy cover after 36 days of recovery in the greenhouse was 71.9% higher for 8% SWC treated plants than in 12% and 20% SWC treated plants. Turfgrass managers may benefit from annual bluegrass putting green management strategies to reduce fall soil moisture. Given that soil moisture did not significantly influence carbohydrate or lipid peroxidation results, except for in roots, additional research is needed to understand the mechanism associated with these findings.

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.

Effect of co-inoculation of Lactobacillus plantarum and Lentilactobacillus buchneri on aerobic stability and microbial community composition of perennial sorghum silage

In the present study, the aerobic stability of perennial sorghum (Sorghum bicolor × Sorghum propinquum) silage following exposure to air was evaluated, which was pretreated with either Lactiplantibacillus plantarum (L group) or Lactiplantibacillus plantarum + Lentilactobacillus buchneri (M group). Samples from the M group had lower dry matter loss rates and higher acetic acid content after exposure to air. Furthermore, samples from the M group showed high levels of water-soluble carbohydrates (2.79–6.55% in dry matter) and crude protein (3.82–9.02% in dry matter) after exposure to air. Moreover, M pretreatment led to the inhibition of the growth of Debaryomyces hansenii whereas it promoted the growth of Levilactobacillus and Clavispora sp. Overall, M pretreatment of perennial sorghum during storage hindered aerobic deterioration and promoted the formation of total fermentation products that act as precursors for biogas production.

Isolation and identification of ligninolytic bacterium (Bacillus cereus) from buffalo (Bubalus bubalis) rumen and its effects on the fermentation quality, nutrient composition, and bacterial community of rape silage.

This study aimed to isolate and identify a ligninolytic bacterium from the rumen of buffalo (Bubalus bubalis) and investigate its effects as a silage additive for whole-plant rape. Three lignin-degradation strains were isolated from the buffalo rumen, with AH7-7 being chosen for further experiments. Strain AH7-7, with acid tolerance and a 51.4% survival rate at pH 4, was identified as Bacillus cereus. It exhibited a lignin-degradation rate of 20.5% after being inoculated in a lignin-degrading medium for 8 days. We divided the rape into four groups according to the various additive compositions to examine the fermentation quality, nutritional value, and bacterial community after ensiling: Bc group (inoculated with B. cereus AH7-7 3.0 × 106 CFU g FW-1), Blac group (inoculated with B. cereus AH7-7 1.0 × 106 CFU g FW-1, L. plantarum 1.0 × 106 CFU g FW-1, and L. buchneri 1.0 × 106 CFU g FW-1), Lac group (inoculated with L. plantarum 1.5 × 106 CFU g FW-1 and L. buchneri 1.5 × 106 CFU g FW-1), and Ctrl group (no additives). After 60 days of fermentation, the application of B. cereus AH7-7 was potent in modulating the fermentation quality of silage, especially when combined with L. plantarum and L. buchneri, as indicated by lower dry matter loss and higher contents of crude protein, water-soluble carbohydrate, and lactic acid. Furthermore, treatments with the B. cereus AH7-7 additive decreased the contents of acid detergent lignin, cellulose, and hemicellulose. The B. cereus AH7-7 additive treatments reduced the bacterial diversity and optimized the bacterial community compositions of silage, with an increase in the relative abundance of beneficial Lactobacillus and a decrease in the relative abundance of undesirable Pantoea and Erwinia. Functional prediction revealed that inoculation with B. cereus AH7-7 could increase the cofactors and vitamins metabolism, amino acid metabolism, translation, replication and repair, and nucleotide metabolism, while decreasing the carbohydrate metabolism, membrane transport, and energy metabolism. In brief, B. cereus AH7-7 improved the microbial community, fermentation activity, and ultimately the quality of silage. The ensiling with B. cereus AH7-7, L. plantarum, and L. buchneri combination is an effective and practical strategy to improve the fermentation and nutrition preservation of rape silage.

Alteration of Carbohydrate Metabolism in Fusarium Infected Wheat Kernels Treated with Fungicides and Its Relation to Baking Technological Parameters and Deoxynivalenol Contamination

Changes of water-soluble carbohydrate (WSC) content such as fructose, glucose, sucrose, maltose, nystose, raffinose, stachyose and fructan were analyzed in wheat kernels in Fusarium epidemic and non-epidemic seasons. In both season types, eight commercial fungicides were applied and three wheat varieties with differing Fusarium resistance were tested. In the epidemic year, the average total amount of WSC was above 1.6% which was 2 times higher than in the non-epidemic year (0.7%). Sucrose, maltose, raffinose and fructan components determined the increased WSC value, but the most substantial change was observed in maltose content where its average amount was 28 times higher in the epidemic year. Fungicide application also significantly increased all the carbohydrate components except maltose, where significant reduction was observed. WSC components had strong correlation with several farinograph or extensograph parameters, but only the maltose content showed positive strong correlation (r = 0.9) with deoxynivalenol (DON) toxin that was highly affected by the applied fungicide. The changes of WSC indicate altered carbohydrate synthesis along with abnormal degradation processes and thus have impaction on the baking features. It seems that the sugar metabolism interacts with DON synthesis and the results give important additional information to the altered metabolism of the attacked plant.

Alternations of ensiling performance and bacterial community in response to different native grassland in Mongolian Plateau

The aim of this study was to investigate the dynamics of bacterial communities and natural fermentation quality in three steppe types [meadow steppe (MS); typical steppe (TS); and desert steppe (DS)] on the Mongolian Plateau. PacBio single molecule with real-time sequencing technology was applied to provide insights into the dynamics of the physicochemical characteristics and the complex microbiome of native grass after 1, 7, 15, and 30 days of fermentation process. The dry matter, crude protein, and water soluble carbohydrate (WSC) contents of the three groups slowly decreased after 1 day of fermentation process, and the lowest WSC concentration after 30 days of ensiling was detected in the DS group compared to that in the MS and TS groups. There was no significant effect of steppe types on lactic acid and butyric acid content (P>0.05). The pH was higher in the early stages of fermentation. After 30 days of fermentation, the pH of MS and DS dropped to ∼5.60, while TS was as high as 5.94. At different ensiling days, the pH of TS was significantly higher than that of MS (P<0.05). The ammonia nitrogen content of MS was significantly higher than TS and DS (P<0.05). During the whole fermentation process, Leuconostoc mesenteroides and Pseudocitrobacter faecalis were the main species of DS, while Enterobacter roggenkampii and Faecalibacterium prausnitzii dominated the fermentation process in MS and TS, respectively. The fermentation quality of native grass silage of different steppe types was less satisfactory, with the silage quality ranging from DS, MS, and TS in descending order. The epiphytic bacteria dominating the fermentation process differed between steppe types of silage. Leuconostoc mesenteroides as the main strain of DS had a modulating effect on pH and LA content, while the main strains of MS and TS (Enterobacter roggenkampii and Faecalibacterium prausnitzii) dominated the silage without significant effect on improving fermentation characteristics and nutritional quality.

Study on the effect of additives on microbial diversity, predicted functional profiles, and fermentation quality of Broussonetia papyrifera and Pennisetum sinese mixed ensilage in the karst region.

In this research, we evaluated the effect of exogenous lactic acid bacteria and Amomum villosum essential oil (AVEO) on the chemical composition, microbial community composition, microbial functional diversity, and fermentation quality of Broussonetia papyrifera (BP) and Pennisetum sinese (PS) mixed silages. The BP:PS mixing ratios were 100:0, 70:30, 50:50, 30:70, and 0:100. After 3 and 30 days of ensiling at 22°C-25°C, microbial diversity and function, and fermentation quality, were assessed. Increasing PS content resulted in decreased ammoniacal nitrogen and pH, increased water-soluble carbohydrate content, increased relative abundance of Lactococcus and Acinetobacter, and reduced relative abundance of Caproiciproducens and Pseudomonas. A 50:50 BP:PS ratio effectively improved the fermentation quality compared to anaerobic fermentation with BP or PS alone, while AVEO treatment further improved fermentation quality by increasing Lactococcus relative abundance. Moreover, as fermentation proceeded, ensiling enhanced the 'Human diseases', 'Environmental information processing', and 'Cellular processes' functions at the first level, as well as the 'Two-component system' and 'ABC transporters' functions at the third level. Different additives affected the fermentation of BP and PS mixed silage by regulating microbial community succession and metabolic pathways during ensiling.

Anaerobic fermentation featuring wheat bran and rice bran realizes the clean transformation of Chinese cabbage waste into livestock feed.

Rapid aerobic decomposition and a high cost/benefit ratio restrain the transformation of Chinese cabbage waste into livestock feed. Herein, anaerobically co-fermenting Chinese cabbage waste with wheat bran and rice bran at different dry matter levels (250, 300, 350 g/kg fresh weight) was employed to achieve the effective and feasible clean transformation of Chinese cabbage waste, and the related microbiological mechanisms were revealed by high-throughput sequencing technology. The bran treatments caused an increase in pH value (4.75-77.25%) and free amino acid content (12.09-152.66%), but a reduction in lactic acid concentration (54.58-77.25%) and coliform bacteria counts (15.91-20.27%). In addition, the wheat bran treatment improved the levels of short-chain fatty acids, nonprotein nitrogen, water-soluble carbohydrates and antioxidant activity and reduced the ammonia nitrogen contents. In contrast, the rice bran treatment decreased the levels of acetic acid, water-soluble carbohydrates, nonprotein nitrogen, ammonia nitrogen, and antioxidant activities. Microbiologically, the bran treatments stimulated Pediococcus, Lactobacillus, Enterobacter, and Weissella but inhibited Lactococcus and Leuconostoc, which were the primary organic acid producers reflected by the redundancy analysis. In addition, Chinese cabbage waste fermented with wheat bran at 350 g/kg fresh weight or with rice bran at 300 g/kg fresh weight increased the scale and complexity of bacteriome, promoted commensalism or mutualism and upregulated the global metabolism pathways, including carbohydrate and amino acid metabolisms. Furthermore, the bran treatments resulted in an increase in bacterial communities that were facultatively anaerobic, biofilm-formed, Gram-negative, potentially pathogenic and stress-tolerant. Collectively, the bran treatments inhibited effluent formation and protein degradation and improved nutrient preservation but reduced organic acid production during the anaerobic fermentation, which is linked to the variations in the bacteriome, indicating that the constructed fermentation system should be further optimized.