Residual Water-soluble Carbohydrate Research Articles

Epiphytic microbiota source stimulates the fermentation profile and bacterial community of alfalfa-corn mixed silage.

The epiphytic microbiota source on plants plays a crucial role in the production of high-quality silage. To gain a better understanding of its contribution, the microbiota of alfalfa (M1C0), corn (M0C1) and the resulting mixture (M1C1) was applied in alfalfa-corn mixed silage production system. M1C0 decreased ammonia-N levels in terms of total nitrogen (57.59-118.23 g/kg TN) and pH (3.59-4.40) values (p < 0.01), which increased lactic acid (33.73-61.89 g/kg DM) content (p < 0.01). Consequently, this resulted in higher residual water-soluble carbohydrate (29.13-41.76 g/kg DM) and crude protein (152.54-167.91 g/kg DM) contents, as well as lower NDF (427.27 g/kg DM) and ADF (269.53 g/kg DM) contents in the silage compared to M1C1- and M0C1-treated samples. Moreover, M1C0 silage showed significantly higher bacterial alpha diversity indices (p < 0.05), including the number of observed species and Chao1 and Shannon diversity indices, at the later stages of ensiling. Lactobacillus, Kosakonia and Enterobacter were the dominant bacterial species in silages, with a relative abundance of >80%. However, the abundance of Lactobacillus amylovorus in M0C1- and M1C1-treated silage increased (p < 0.01) in the late stages of ensiling. These findings confirmed that the epiphytic microbiota source exerts competitive effects during anaerobic storage of alfalfa-corn mixed silage.

Effect of Lactiplantibacillus and sea buckthorn pomace on the fermentation quality and microbial community of paper mulberry silage.

Paper mulberry is a promising alternative fodder source due to its high protein and the abundance of active components. However, paper mulberry often faces susceptibility to contamination during silage fermentation, and there is a need to improve the quality of silage fermentation of paper mulberry through exotic additives. Sea buckthorn pomace (BP) is a feed additive containing antimicrobial and antioxidant substances that help to enhance silage fermentation. Therefore, the objective of this study was to evaluate the effects of BP and Lactiplantibacillus as additives on silage fermentation and bacterial community of paper mulberry. The results showed that BP and Lactiplantibacillus significantly reduced the pH and ammonium nitrogen content of paper mulberry silage (P < 0.05) and significantly increased the content of lactic acid and acetic acid (P < 0.05), resulting in more residual water-soluble carbohydrate and crude protein contents and less fiber content relative to the control. The key microorganisms in paper mulberry silage fermentation are Lactiplantibacillus pentosus and Weissella cibaria. Among these, Lactiplantibacillus favored a rapid increase in Lactiplantibacillus pentosus abundance during the pre-silage fermentation period, whereas BP favored the promotion of Lactiplantibacillus pentosus growth, resulting in higher contents of lactic and acetic acid than those of the control. Simultaneously adding Lactiplantibacillus and BP can effectively improve the quality of paper mulberry silage and increase the abundance of beneficial microorganisms in paper mulberry silage.

Effects of grass silage, preserved using formic acid or lactic acid bacteria, on milk production of dairy cows, supplemented with concentrates high or low in metabolizable protein

A continuous production experiment was conducted in Norway with 48 Norwegian Red dairy cows in early- to mid-lactation, to investigate the effect of grass silage with lactic acid bacteria (LAB) or formic acid (FA) additives, on milk yield (MY) and milk protein yield (MPY). Grass wilted to 250 g dry matter (DM)/kg was inoculated with homofermentative LAB to obtain LAB silage, whilst FA silage was produced adding a FA-based additive. The two silages were fed ad libitum and supplemented with an average 10.3 kg of either high (H) or low (L) metabolizable protein (MP) concentrates, in a 2 ✗ 2 factorial arrangement of treatments. The treatments were LAB silage and L concentrate, LAB silage and H concentrate, FA silage and L concentrate and FA silage and H concentrate. The use of FA resulted in lower levels of residual water-soluble carbohydrates (WSC), and higher levels of ammonia nitrogen (NH3N), compared to LAB. In situ results for FA silage showed lower rumen degradability of crude protein (CP), while gas in vitro results showed lower utilizable CP (uCP), compared to LAB silage (782 vs. 750 g/kg DM and 128 vs. 119 g/kg DM, respectively). The purine over creatinine (PDC) index did not indicate any effects on the microbial protein synthesis (MPS) from any of the treatments. The higher daily intake of FA silage (12.5 vs.13.7 kg DM for LAB and FA, respectively, P < 0.001), did not result in significant differences in daily MY (31.0 vs. 30.2 kg, P = 0.208), nor MPY (1.08 vs.1.07 kg/day, P = 0.878) for LAB and FA, respectively. Feeding H concentrate gave higher MPY (P = 0.036), higher urea in milk (P < 0.001), plasma (P < 0.001) and urine (P = 0.008) and tended to give higher MY (P = 0.063) for both silages. For amino acids (AA) in plasma, alanine was higher for FA silage than for LAB silage (P = 0.030), while histidine (P = 0.001), leucine (P = 0.015) and glutamine (P = 0.007) were higher for both silages when cows were fed H concentrate. In conclusion, the FA and LAB additives did not affect MY or MPY any differently. Feeding H concentrate resulted in higher MPY for both silages, but reduced nitrogen (N) efficiency.

Lentilactobacillus buchneri Preactivation Affects the Mitigation of Methane Emission in Corn Silage Treated with or without Urea

The aim of this study was to investigate the effect of different forms of Lentilactobacillus buchneri on the in vitro methane production, fermentation characteristics, nutritional quality, and aerobic stability of corn silage treated with or without urea. The following treatments were applied prior to ensiling: (1) no urea treatment and LB; (2) no urea treatment+freeze dried LB; (3) no urea treatment+preactivated LB; (4) with urea treatment+no LB; (5) with urea treatment+freeze dried LB; (6) with urea treatment+preactivated. LB was applied at a rate of 3 × 108 cfu/kg on a fresh basis, while urea was applied at a rate of 1% on the basis of dry matter. Data measured at different time points were analyzed according to a completely randomized design, with a 2 × 3 × 5 factorial arrangement of treatments, while the others were analyzed with a 2 × 3 factorial arrangement. Preactivated LB was more effective than freeze-dried LB in reducing silage pH, ammonia nitrogen, cell-wall components, yeast count, and carbon dioxide production, as well as increasing lactic acid and residual water-soluble carbohydrate and aerobic stability (p &lt; 0.0001). A significant reduction in the methane ratio was observed after 24 h and 48 h incubation with preactivated forms of LB (p &lt; 0.001). The results indicated that preactivated LB combined with urea improved fermentation characteristics, nutritional quality, and aerobic stability and reduced the methane ratio of corn silages.

Effect of Sorbic Acid, Ethanol, Molasses, Previously Fermented Juice and Combined Additives on Ensiling Characteristics and Nutritive Value of Napiergrass (Pennisetum purpureum) Silage

The effects of sorbic acid, ethanol, previously fermented juice and their combined additives on fermentation quality and residual water-soluble carbohydrates (WSC) of napiergrass (Pennisetum purpureum) were herein investigated. There were two experiments in total. The treatments of experiment 1 were as follows: control (no addition); sorbic acid at 0.1%, S; molasses at 1.0%, M; previously fermented juice at 5 mL/kg, P; SP; SM; SPM. The treatments of experiment 2 were as follows: control (no addition); ethanol at 1.5%, E; molasses at 1.0%, M; previously fermented juice at 5 mL/kg, P; EM; EP; EPM. The laboratory silos (10 L) were kept at room temperature (~25 °C), and opened after 120 days of ensiling and the chemical compositions of silage were analyzed. Sorbic acid addition significantly (p &lt; 0.05) decreased the silage pH and increased the residual WSC and lactic acid (LA) contents as compared with control. Ethanol addition decreased pH, acetic acid (AA) and volatile fatty acids (VFAs) contents, and increased the ratio of LA/AA, LA and residual WSC contents. Molasses addition increased ratios of LA/AA and enhanced WSC content used by lactic acid bacteria (LAB). The PFJ addition increased AA and ammonia nitrogen/total nitrogen (AN/TN) and decreased the LA contents. Comparing the fermentation quality among all silages in the present study, the combined additives SM and EM performed best in improving the silage quality of napiergrass.

Nutritive value, silage fermentation characteristics, and aerobic stability of grass-legume round-baled silages at differing moisture concentrations with and without manure fertilization and microbial inoculation.

For baled silages, production of clostridial fermentation products can be exacerbated by exceeding normal moisture targets (45% to 55%), and/or by the application of dairy slurry before harvest. Our objectives were to test a microbial inoculant as a mitigant of clostridial products in high-moisture, grass-legume (52% ± 13.8% cool-season grasses, 44.0% ± 14.0% legumes [predominately alfalfa]) baled silages in swards that were fertilized with dairy slurry. A secondary objective was to examine the effects of bale moisture and inoculation on the aerobic stability of these fermented silages following exposure to air. After the first-cutting was removed, three manure treatments were applied as a whole-plot factor: 1) control (no manure); 2) slurry applied immediately to stubble (63,250 L/ha); or 3) slurry applied after a 1-wk delay (57,484 L/ha). An interactive arrangement of bale moisture (64.1% or 48.4%) and inoculation (yes or no) served as a subplot term in the experiment. The inoculant contained both homolactic (Lactococcus lactis 0224) and heterolactic (Lactobacillus buchneri LB1819) bacteria. The experimental design was analyzed as a randomized complete block with four replications, and the study included 48 experimental units (1.2 × 1.2-m round bales). Total fermentation acids were affected (P ≤ 0.021) by slurry application strategies, but this was likely related to inconsistent bale moisture across slurry-application treatments. Concentrations of butyric acid were low, and there were no detectable contrasts comparing manure treatments (mean = 0.05%; P ≥ 0.645). Bale moisture affected all measures of fermentation, with bales made at 64.1% moisture exhibiting a more acidic final pH (4.39 vs. 4.63; P < 0.001), less residual water-soluble carbohydrates (2.1% vs. 5.1%; P < 0.001), as well as greater lactic acid (4.64% vs. 2.46%; P < 0.001), acetic acid (2.26% vs. 1.32%; P < 0.001), and total fermentation acids (7.37% vs. 3.97%; P < 0.001). Inoculation also reduced pH (4.47 vs. 4.56; P = 0.029), and increased acetic acid (1.97% vs. 1.61%; P < 0.001) and 1,2-propanediol (1.09% vs. 0.72%; P < 0.001) compared to controls. During a 34-d aerobic exposure period, maximum surface bale temperatures were not affected (P ≥ 0.186) by any aspect of treatment, likely due to the prevailing cool ambient temperatures; however, yeast counts were numerically lower in response to greater (P < 0.001) production of acetic acid that was stimulated by both high bale moisture and inoculation.

Lignocellulose Degradation and Enzymatic Hydrolysis of Soybean Incorporated Sorghum Silage Inoculated with Feruloyl-Esterase Producing Lactobacillus plantarum

Availability of feedstock is one of the uncertainties impeding cellulosic biofuel production, and conservation of whole crop biomass as silage is a promising method to ensure year-round feedstock availability for biofuel production. This study investigated lignocellulose degradation and subsequent enzymatic hydrolysis of a 90-d sorghum silage incorporated with soybean and inoculated with Lactobacillus plantarum A1 in a three (0, 25, and 50%; soybean inclusions) by two (uninoculated and inoculated) factorial experiment. The results revealed that L. plantarum A1 inoculated silages had improved fermentation characteristics. The silages’ total N and non-fiber carbohydrate increased with L. plantarum A1 and soybean inclusion (p &lt; 0.05). Inoculation also increased the residual water-soluble carbohydrate by 33.9% (p &lt; 0.05). Inoculation and soybean inclusion significantly hydrolyzed the biomass’ lignocellulose, altered its morphology and microstructural matrix, increased production of ferulic acid and reduced the biomass crystallinity by 15.60% (p &lt; 0.05). L. plantarum A1 inoculation × soybean inclusion improved glucose yield and cellulose conversion during enzymatic saccharification compared to uninoculated treatments. Therefore, incorporating soybean into sorghum silage with L. plantarum A1 inoculation enhanced fermentation quality, lignocellulose degradation and enzymatic saccharification which could serve as a sure way for sustainable year-round feedstock supply for enhanced biofuel production.

Gamma-ray irradiation and microbiota transplantation to separate the effects of chemical and microbial diurnal variations on the fermentation characteristics and bacterial community of Napier grass silage.

To investigate the contributions of chemical and microbial diurnal variations in fermentation characteristics and bacterial community of Napier grass silage, gamma-ray irradiated Napier grass harvested at 07.00 h (AM), 12.00 h (M) and 17.00 h (PM) was inoculated with the microbiota derived from Napier grass harvested at AM, M and PM in a 3 (irradiated forage: AMG , MG and PMG ) × 3 (microbiota: AMM , MM and PMM ) design and then ensiled for 14 and 60 days. Napier grass harvested at various times had different chemical compositions and epiphytic microbiota prior to ensiling. For silages inoculated with the same microbiota, the pH values, residual water soluble carbohydrates and dry matter contents increased, and lactic acid, acetic acid, propionic acid, butyric acid, ethanol and volatile fatty acids contents decreased in PMG and MG silages compared to AMG silages. MM and PMM inoculum promoted lactic acid fermentation as indicated by higher lactic acid contents and lactic/acetic acid ratios in MM and PMM -inculated silages compared to those in AMM -inoculated silages after 60 days of ensiling. During ensiling, epiphytic microbiota affected the Chao1 index, operational taxonomic units (OTUs) number and Shannon index, as well as the abundances, of more than half of the top 10 abundant genera, whereas chemical composition did not affect any of the bacterial diversity and richness indices and only showed significant impacts on the abundances of two genera. The results indicated that chemical diurnal variation exerted an influence mainly on the extent of fermentation, whereas microbial diurnal variation affected more the bacterial community and fermentation types during Napier grass ensiling. © 2022 Society of Chemical Industry.

Effects of Delayed Harvest and Additives on Fermentation Quality and Bacterial Community of Corn Stalk Silage.

This study aimed to investigate the effects of delayed harvest and additives on the fermentation quality and bacterial community of corn stalk silage in South China. The corn stalks after ear harvest at the 0 day (D0), 7 days (D7), and 15 days (D15) were used to produce small-bale silages. The silages at each harvest time were treated without (control, CK) or with Lactobacillus plantarum (LP) and sodium benzoate (BF). The results showed that delayed harvest increased pH and acetic acid content and reduced lactic acid content in corn stalk silage (p < 0.05). Compared with CK, the additives decreased the contents of butyric acid and ammonia nitrogen (NH3-N; p < 0.05). The silage treated with LP increased the content of lactic acid and decreased pH (p < 0.05); the silage treated with BF decreased counts of coliform bacteria and yeasts and increased residual water soluble carbohydrates (WSC) content (p < 0.05). Single Molecule, Real-Time sequencing (SMRT) revealed that the abundance of L. plantarum increased, while the abundance of Lactobacillus brevis and Lactobacillus ginsenosidimutans decreased with the delayed harvest. Additives influenced the bacterial community structure of corn stalk silage, revealed by enhanced bacterial diversity on D0 and reduced on D7 (p < 0.05). Our research indicated that delayed harvest could exert a positive effect on acetic acid production, and additives could inhibit the butyric acid fermentation and protein degradation of corn stalk silage by shifting bacterial community composition.

Evaluation of the Tolerance Ability of Wheat Genotypes to Drought Stress: Dissection through Culm-Reserves Contribution and Grain Filling Physiology

Drought stress is one of the limiting factors for grain filling and yield in wheat. The grain filling and determinants of individual grain weight depend on current assimilation and extent of remobilization of culm reserves to grains. A pot experiment was conducted with eight wheat cultivars at the Pot House to study the grain filling and the contributions of reserves in culm, including the sheath to grain yield under drought stress. Drought stress was enforced by restricting irrigation during the grain-filling period. The plants (tillers) were harvested at anthesis, milk-ripe, and maturity. The changes in dry weights of leaves, culm with sheath, spikes, and grains; and the contribution of culm reserves to grain yield were determined. Results revealed that drought stress considerably decreased the grain filling duration by 15–24% and grain yield by 11–34%. Further, drought-induced early leaf senescence and reduced total dry matter production indicate the minimum contribution of current assimilation to grain yield. The stress reduced the contribution of culm reserves, the water-soluble carbohydrates (WSCs), to the grains. The accumulation of culm WSCs reached peak at milk ripe stage in control, varied from 28.6 to 84 mg culm−1 and that significantly reduced in the range from 14.9 to 40.6 mg culm−1 in stressed plants. The residual culm WSCs in control and stressed plants varied from 1.23 to 8.12 and 1.00 to 3.40 mg g−1 culm dry mass, respectively. BARI Gom 24 exhibited a higher contribution of culm WSCs to grain yield under drought, while the lowest contribution was found in Kanchan. Considering culm reserves WSCs and their remobilization along with other studied traits, BARI Gom 24 showed greater drought tolerance and revealed potential to grow under water deficit conditions in comparison to other cultivars.

Effect of storage time and the level of formic acid on fermentation characteristics, epiphytic microflora, carbohydrate components and in vitro digestibility of rice straw silage.

ObjectiveThe study aimed to evaluate the effect of storage time and formic acid (FA) on fermentation characteristics, epiphytic microflora, carbohydrate components and in vitro digestibility of rice straw silage.MethodsFresh rice straw was ensiled with four levels of FA (0%, 0.2%, 0.4%, and 0.6% of fresh weight) for 3, 6, 9, 15, 30, and 60 d. At each time point, the silos were opened and sampled for chemical and microbial analyses. Meanwhile, the fresh and 60-d ensiled rice straw were further subjected to in vitro analyses.ResultsThe results showed that 0.2% and 0.6% FA both produced well-preserved silages with low pH value and undetected butyric acid, whereas it was converse for 0.4% FA. The populations of enterobacteria, yeasts, moulds and aerobic bacteria were suppressed by 0.2% and 0.6% FA, resulting in lower dry matter loss, ammonia nitrogen and ethanol content (p<0.05). The increase of FA linearly (p<0.001) decreased neutral detergent fibre and hemicellulose, linearly (p<0.001) increased residual water soluble carbohydrate, glucose, fructose and xylose. The in vitro gas production of rice straw was decreased by ensilage but the initial gas production rate was increased, and further improved by FA application (p<0.05). No obvious difference of FA application on in vitro digestibility of dry matter, neutral detergent fibre, and acid detergent fibre was observed (p>0.05).ConclusionThe 0.2% FA application level promoted lactic acid fermentation while 0.6% FA restricted all microbial fermentation of rice straw silages. Rice straw ensiled with 0.2% FA or 0.6% FA improved its nutrient preservation without affecting digestion, with the 0.6% FA level best.

Grass size and butterfly pea inclusion modify the nutritional value of elephant grass silage

Abstract: The objective of this work was to evaluate the nutritional value of silages from tall-sized and dwarf elephant grass (Pennisetum purpureum) genotypes, intercropped or not with butterfly pea (Clitoria ternatea). The experiment was performed in randomized complete blocks, in a 4x2 factorial arrangement (four genotypes × two cropping systems). The genotypes intercropped or not with butterfly pea were: IRI-381 and Elephant B, tall sized; and Taiwan A-146 2.37 and Mott, dwarf. Forage was harvested 60 days after regrowth. In the silage from Mott grass intercropped with butterfly pea, lower contents of lignin (78.1 g kg-1), neutral detergent fiber (636.0 g kg-1), and neutral detergent insoluble protein (13.15 g kg-1), besides a greater dry matter recovery (873.3 g kg-1), were observed. The silage from Taiwan A-146 2.37 intercropped with the legume showed a greater crude protein content (136.1 g kg-1). In both silages, the ammonia nitrogen contents were quite reduced (26.4 g kg-1). However, greater residual water-soluble carbohydrate contents were observed in the silages from the intercrop (1.85 mg g-1) and from the Mott grass monocrop (1.51 mg g-1). Moreover, there was a lower in vitro dry matter digestibility (676.7 g kg-1) for the silage from the intercrop. Dwarf genotypes increase the nutritional value of elephant grass silage, compared with the tall-sized ones. Intercropping with butterfly pea improves silage fermentation characteristics, despite reducing its digestibility. Therefore, the ensilage of dwarf Mott elephant grass intercropped with butterfly pea shows more promising results.

Selection of Lactic Acid Bacteria from Alfalfa Silage and Its Effects as Inoculant on Silage Fermentation

The first part of the study aimed to isolate, characterize, and identify wild lactic acid bacteria (LAB) strains from alfalfa silage produced in a tropical area. LAB strains were isolated from alfalfa silage ensiled for 1, 3, 7, 14, 28, and 56 days (d) and were identified by sequencing the 16S rRNA gene. The second part aimed to investigate the effects of wild LAB strains on the nutritive and fermentative characteristics of alfalfa silage. This trial was conducted according to a completely randomized design in a 4 × 2 factorial scheme [four inoculants (I) × two harvests (H)], (n = 4). The inoculants were: (1) no inoculant (CTRL), (2) Lactobacillus pentosus (AV 14.17); (3) L. pentosus + Lactobacillus brevis + Pediococcus acidilactici (Combo); and (4) commercial inoculant (CI). Alfalfa forage (7 kg) was ensiled in 10 L buckets and opened after 90 d. Seventy-seven strains were isolated. Pediococcus, Lactobacillus, and Weissella represented 52.0, 24.7, and 20.8% of the isolates, respectively. For the first harvest, Combo, CI, and all inoculated silages showed lower acid detergent fiber ADF, neutral detergent fiber (NDF), and ammonia nitrogen (NH3-N), respectively. Silage fermented with AV14.17 presented greater residual water-soluble carbohydrate (WSC) in the second harvest and showed the lowest pH in both harvests. AV14.17 strain has potential as an inoculant for alfalfa silage production.

Effect of Selected and Beneficial Lactic Acid Bacteria as Inoculants for Corn and Sorghum Silages

The preliminary effect of Lactobacillus fermentum CRL2085, alone or in combination with the homofermentative Pediococcus acidilactici CRL2043 on the fermentation and aerobic stability of corn and sorghum silages, was investigated. To be used as silages inoculants, these lactic acid bacteria (LAB) were screened for fibrolytic, amylolytic and antifungal activities. Laboratory silos were prepared, inoculated at 105 CFU/g and fermented during 45 days 25 ºC. At the end of fermentation, Pediococcus acidilactici-inoculated corn and sorghum silages exhibited the lowest pH and high residual water-soluble carbohydrates (WSC). Forage silages inoculated with Lactobacillus fermentum + Pediococcus acidilactici showed Lower Dry matter (DM) losses and Neutral Detergent Fiber (NDF) values, while higher residual WSC concentration than Lactobacillus fermentum-inoculated silages, thus silage digestibility must be improved. Yeast activity was impaired in silages inoculated with Lactobacillus fermentum alone or combined with Pediococcus acidilactici and aerobic stability improved. The survival of LAB used as inoculants during fermentation was suggested by PCR. Besides the good performance as silages inoculants, LAB previously selected as having health benefits may be delivered to cattle in feedlot through fermented silage as a vehicle

Effects of Ensiling Oxytropis glabra with Whole-Plant Corn at Different Proportions on Fermentation Quality, Alkaloid Swainsonine Content, and Lactic Acid Bacteria Populations.

Simple SummaryIn Inner Mongolia, developing innovative forages is an indispensable way to ease the shortage of animal feed. Oxytropis glabra (OG) has become a dominant population, with a high nature yield in the degraded grassland of Inner Mongolia. As a typical legume, it is rich in amino acids and trace elements, so using OG to feed livestock is a valuable strategy. However, it contains swainsonine (SW), which hinders the utilization of OG. This study was conducted to evaluate silage fermentation and SW removal from OG ensiled with whole-plant corn at different proportions, and the result showed ensiling a mixture of OG and corn could be a valuable approach for producing livestock feed, as it had a positive effect on fermentation quality and SW detoxification; the optimal ratio was 1:1. In the silages, Lactobacillus plantarum was the most common microorganism present in all mixture silages, and Lactobacillus amylovorus and Lactobacillus brevis were prevalent at lower ratios of corn to OG. All representative strains were able to remove SW from OG fermentation, and the strains of L. amylovorus and L. plantarum had a higher SW removal rate. These mixtures of silages could make OG useable as a feed source in ruminant production.Oxytropis glabra (OG) is a leguminous forage that is potentially valuable for solving the shortage of feed for livestock production, while, in large quantities, it may be toxic because of its swainsonine (SW) content. In this study, OG was ensiled with whole-plant corn (Zea mays L.) at 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, and 0:10 ratios on a fresh matter basis, and, after 60 d of ensiling, the chemical composition, fermentation characteristic, SW removal rate, lactic acid bacteria (LAB) populations, and their capabilities for SW removal were analyzed. As the proportion of corn in the silage increased, the pH, as well as the propionic acid, ammonia-N, dry matter, crude protein, and SW contents, decreased linearly, while the lactic acid, neutral detergent fiber, and residual water-soluble carbohydrate contents increased linearly. Lactobacillus plantarum was the most common microorganism present in all mixture silages. Lactobacillus amylovorus and Lactobacillus brevis were prevalent at lower ratios of corn to OG. Meanwhile, the LAB strains belong to L. amylovorus and L. plantarum had a higher SW removal rate. Our results suggested that ensiling OG with whole-plant corn improves fermentation and decreases SW content, and that 5:5 is the optimal ratio, so this type of mixed silage could make OG useable for ruminant production.

Effect of wet sea buckthorn pomace utilized as an additive on silage fermentation profile and bacterial community composition of alfalfa

To effectively preserve nutrients, alfalfa silage was treated without (control) or with Lactobacillus plantarum (LP) and their mixture (LP + SBP). Results showed that SBP decreased (P < 0.05) final pH value and ammonia-N of total N, increased (P < 0.05) lactic, acetic and propionic acid contents, resulting in more residual water soluble carbohydrate and crude protein contents and less fiber content in relative to control. Moreover, SBP decreased (P < 0.05) the number of observed species, richness index of ACE and diversity index of Shannon at early stage of ensiling, while Lactobacillus plantarum, Lactococcus lactis, and/or Lactobacillus brevis dominated in silages. In particular, LP + SBP enhanced the growth of Lactococcus lactic at early stage and Lactobacillus plantarum at late stage of ensiling, resulting in higher lactic and acetic acid contents and lower propionic acid content as compared with LP. These confirmed that SBP could be used as an additive for improving silage quality of alfalfa.

Carrot by-product fermentation quality and aerobic spoilage could be modified with silage additives

Vegetable by-products could potentially be suitable to be used as feeds in animal diets, which in general would strengthen the sustainability of both food and feed systems. Two experiments were performed with the objective to evaluate the aerobic spoilage via visual inspection and short term ensiling process of carrot by-products with silage additives (lactic acid bacteria [LAB] inoculants or formic acid [FA]). In the first experiment (Exp. 1), carrot by-product was treated with five additives including a control without additive, two commercial LAB inoculants (heterofermentative and homofermentative), an in-house isolated LAB mixture and a commercial FA based product. Second experiment (Exp. 2) used a 2 × 3 factorial design (type of raw material [carrot by-product with or without pieces] and additive treatment [control, heterofermentative LAB inoculant or FA based product]). Use of FA restricted lactic acid fermentation indicated by the high residual water soluble carbohydrate concentration while simultaneously stimulating ethanol production. LAB inoculants were not able to efficiently affect quality of ensiled carrot by-products. Use of FA also delayed the spoilage of the fresh carrot by-product particularly in Exp. 1.

Enhancement of lignocellulosic degradation in high-moisture alfalfa via anaerobic bioprocess of engineered Lactococcus lactis with the function of secreting cellulase

BackgroundButyric fermentation and a substantial loss of dry matter (DM) often occur in alfalfa silage during the rainy season, which is not conducive to subsequent biofuel production. Currently, there have been negative effects on the combination of cellulases and lactic acid bacteria (LAB) on processing high-moisture alfalfa silage; however, transgenically engineered LAB strains that secrete cellulase have been proposed as an alternative approach to avoid the above problem. The objective of the present study was to construct engineered Lactococcus lactis strains with high-efficiency secretory-expressing cellulase genes from Trichoderma reesei and to investigate the effects of the combination of transgenically engineered L. lactis strains HT1/pMG36e-usp45-bgl1, HT1/pMG36e-usp45-cbh2, and HT1/pMG36e-usp45-egl3 (HT2) on fermentation quality, structural carbohydrate degradability and nonstructural carbohydrate fermentation kinetics of high-moisture alfalfa silage treated without additive as a negative control (Control), or/and with cellulase (EN), wild-type L. lactis subsp. lactis MG1363 (HT1) and the combination of HT1 and EN (HT1 + EN) as positive additive controls.ResultsEngineered L. lactis strains were successfully constructed and efficiently secreted endoglucanase (1118 mU/mL), cellobiohydrolase (222 mU/mL), and β-glucosidase (131 mU/mL) and had high filter paper activity (236 mU/mL). Ensiling experiments verified that HT2 obtained the highest fermentation quality score (83.6) and most efficiently processed high-moisture alfalfa silage, demonstrated by a low pH (4.49) and ammonia-N content (106 g/kg nitrogen) and a high lactic acid content (67.1 g/kg DM) and without butyric acid. Change curves of structural carbohydrates revealed that HT2 degraded more lignocelluloses, demonstrated by the lowest contents of neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose after ensiling for 60 days. Kinetic analysis showed that the most residual water-soluble carbohydrates, glucose, fructose and xylose generated by lignocellulose degradation were produced by HT2, followed by HT1 + EN. The HT2-treated silages had the highest DM recovery, had the fewest Clostridia spores, emitted a fragrance and were not sticky.ConclusionHT2 improved the conversion of lignocellulose to sugars and processed high-moisture alfalfa silage efficiently. This is a novel strategy that can be used to enhance lignocellulosic degradation in high-moisture alfalfa via a bioprocess with transgenically engineered L. lactis strains, which could enhance the development of alfalfa as a biomass feedstock and promote second-generation biofuel development in the rainy season.

Water‐soluble carbohydrates during fermentation and baking of composite wheat and lentil flour—Implications for enhanced functionality

AbstractBackground and objectivesThe nutritional benefits of Lentil (Lens culinaris Medik.) have been widely acknowledged. Enriching wheat flour using pulses such as lentil flour is a way of increasing both the nutritional and functional content of wheat‐based foods. The properties of lentil that may have specific health benefits to the individual are also widely acknowledged. Functional compounds from plant‐based foods are commonly attributed to polyphenols, inhibitors, vitamins, and soluble and insoluble fiber. Water‐soluble carbohydrates, (WSCs) consisting predominantly of oligosaccharides, make up part of total dietary fiber. The beneficial role of oligosaccharides promoting probiotic health is widely acknowledged. Equally, it is recognized that oligosaccharides cause irritable bowel syndrome limiting the ability for some individuals in consuming pulses.FindingsWe investigated changes in water‐soluble carbohydrate (WSC) composition during the dough fermentation phase of bread making and quantified the residual WSC in the bread. As expected, the addition of lentil flour increased the WSC profile of the resulting composite flours which included raffinose, stachyose, ciceritol, and verbascose. A threefold decrease was observed only for verbascose during the dough mixing phase; however, during fermentation, raffinose and stachyose decreased, but ciceritol was not affected.ConclusionsThe baking process may reduce the effects of IBS suffered by some individuals who consume lentil products prepared by traditional methods. Our study concluded that bread prepared from wheat–lentil flour results in a more complex carbohydrate profile and may potentially enhance the prebiotic functionality compared with bread made from wheat alone.Significance and noveltyIt is now recognized that alternate sources of protein can be gained using plant‐based constituents. The functional properties of plant‐based compounds are also widely accepted. Processing, such as fermentation and baking, can alter the concentration and functionality of plant‐based compounds. In this study, we identified the changes in carbohydrate composition that occur in a wheat–lentil composite flour under the conditions of fermentation and baking.

Utilization of a novel feedstuff: effects of additives on the fermentation characteristics, chemical composition and in vitro digestibility of tetraploid black locust (Robinia pseudoacacia) silage

ABSTRACT: This study was conducted to evaluate the effects of additives on the fermentation characteristics, chemical composition and in vitro digestibility of tetraploid black locust (TBL). The TBL leaves silage was either untreated (control) or treated with 1 × 106 cfu/g FM Lactobacillus plantarum (L), 1% glucose (G), 3% molasses (M), a combination of 1% glucose and Lactobacillus plantarum (L+G), or a combination of 3% molasses and Lactobacillus plantarum (L+M). Fermentation quality, chemical composition and nutrient digestibility were then analyzed. Ethanol and acetic acid concentrations were the dominant fermentation products in all silages except L+M silage. The L, G and L+G treatments failed to influence the fermentation. The M treatment increased (P&lt;0.05) the lactic acid concentration and lowered (P&lt;0.05) the pH when compared with control silage. The best fermentation properties were observed in L+M silage, as indicated by the dominance of lactic acid over ethanol in fermentation products. The M and L+M silages exhibited higher (P&lt;0.05) dry matter, and M silage showed higher residual water-soluble carbohydrates than the control. Ensiling increased (P&lt;0.05) the in vitro dry matter, neutral detergent fiber and acid detergent fiber degradability of TBL. Among the silages, M silage had the highest levels of dry matter, neutral detergent fiber and acid detergent fiber degradability. The obtained results suggested that application of lactic acid bacteria together with 3% molasses could be an effective strategy to prevent the occurrence of ethanol fermentation and improve fermentation quality of TBL silage; addition of fermentable sugars to TBL improves nutrient availability to ruminants.