Improved Fermentation Characteristics Research Articles

Determination of the effect of a lactic acid bacteria+enzyme mixture on the silage quality and digestibility of vetch-oat mixture silages

This study was carried out to determine the effects of the addition of lactic acid bacteria+enzyme (LBE) mixture on the fermentation characteristics and digestibility of Hungarian vetch-oat silages. An inoculant was used as additive which contains Lactobacillus plantarum CNCM l-3235, Pediococcus pentosaceus NCIMB 12455, Pediococcus acidilactici CNCM l-3237, Propionibacterium acidipropionici CNCM MA26/4U, alpha-amylase from Bacillus amyloliquefaciens, cellulase from Trichoderma reesei, xylanase from Trichoderma longibrachiatum, beta-glucanase from Aspergillus niger in its biological composition. While additive was not used for control, LBE1 and LBE2 groups were inoculated with LBE as 300 000 and 500 000 cfu/g of silage material, respectively. After 60-d of incubation, no significant difference was observed in pH values among silages, but the highest lactic acid value was detected in the LBE2 group silages (P<0.01). In vitro neutral detergent fiber digestibility (IVNDFD) values of the silages were 41.65, 44.14 and 47.38% for the control, LBE1 and LBE2 groups, respectively, and it was determined that there was a linear correlation (r=0.945) between the inoculant doses and the IVNDFD values. As a result, LBE improved fermentation characteristics and IVNDFD values of the Hungarian vetch-oat mixture.

Effect of Adding Fermented Juice of Epiphytic Lactic Acid Bacteria Prepared with Different Sources and Levels of Soluble Carbohydrates on Chemical Composition, Fermentation and Quality Characteristics of Wheat Straw Silages

This study was conducted in Nutrition laboratory belonged to Animal Production Department-Agriculture College - Al-Qasim Green University to investigate the effect of adding fermented juice of epiphytic lactic acid bacteria (FJLB) prepared with different sources and levels of water soluble carbohydrates (WSC) on chemical composition, fermentation and quality characteristics of wheat straw silages (WSS). The FJLB was prepared from wild reed plant with three sources of WSC including glucose (G) at 1 and 2% (w/v, FJLB-G1, FJLB-G2), cane molasses (M) at 3 and 5% (w/v, FJLB-M3, FJLB-M5) and date molasses (D) at 3 and 5% (w/v, FJLB-D3, FJLB-D5). According to the source and level of FJLB, six samples of WSS were prepared by adding each FJLB at level of 1%. For control WWS, distilled water was added at similar quantity as FJLB (WWS-C). Urea and molasses were added to all samples at level of 1 and 10% on dry matter (DM) basis. Samples of WSS were tightly packed in double plastic bags and ensiled anaerobically for 45 days. Color of WSS samples were characterized with acceptable smell. Results showed that there was a significant decrease (p<0.01) in DM content of WWS samples prepared with FJLB-M3 and FJLB-M5 as compared with WWS-C. However, crude protein (CP), ether extract (EE) and crude fiber (CF) contents in WWS were not affected by addition of FJLB. Addition of FJLB improved fermentation characteristics of WWS, lactic acid (LA) and volatile fatty acids (VFA) were significantly (p<0.01) increased. Moreover, lower (p<0.01) DM losses were estimated in WSS prepared FJLBs.

Fermentation Characteristics and Nutritional Value of Avena sativa Genotypes Ensiled with or without Napier Grass (Pennisetum purpureum)

The objective of this study was to investigate the fermentation characteristics and nutritional value of A. sativa genotypes ensiled either solely or in combination with P. purpureum 16791. Three different A. sativa genotypes (SRCPX80AB2806, ILRI_5527A, and ILRI_5526A) were harvested at the dough stage and ensiled solely or in combination with equal parts of P. purpureum 16791 with the addition of 3% molasses for all treatments in a completely randomized design with three replications over a period of 45 days. P. purpureum harvested at 60 days was ensiled and used as a control treatment. All treatments were evaluated for fermentation characteristics (pH, temperature, physical properties, and flieg point) and subjected to chemical analysis. The results showed that ensiling A. sativa ILRI_5527A, in combination with equal parts of P. purpureum 16791, produced the best silage with a significantly lower pH of 3.52. Optimal temperature (25 °C), nutrient losses based on the total dry matter (2.17%), gas (3.74%), and effluent (4.28%) were significantly (p &lt; 0.0001) lower for T6 compared to the others. The dry matter recovery rate of T6 was significantly (p &lt; 0.0001) higher than that of the others. T6 ranked first in the quality of physical properties (smell, color, mold, and texture). The highest dry matter (24%), organic matter (96.80%), crude fat (3.32%), and metabolizable energy (10.05 MJ/kg DM) were recorded for T6. The flieg score for T6 silage (96.6%) was also better than the others. In conclusion, ensiling A. sativa ILRI_5527 with equal parts of P. purpureum 16791 and the addition of 3% molasses improved fermentation characteristics and silage quality.

Fermentation characteristics and microbial counts of Megathyrsus maximus silage as influenced by Moringa oleifera seeds and ensiling period

Abstract The fermentation characteristics and microbial counts of Megathyrsus maximus ensiled at varying inclusions of Moringa oleifera seeds at different ensiling periods were investigated. Factorial experiment consisting of 3 varying proportions of grass and seeds (100:0, 75:25, and 50:50) and 4 ensiling duration (30, 60, 90, and 120 days) was carried out. The pH was significantly highest (p &lt; 0.05) with the highest inclusion of seeds while pH decreased with increased ensiling duration. Colour and odour changed as the level of seed inclusion increased in the silage while the moisture content (9.10) was significantly higher (p &lt; 0.05) at 30 days of ensiling. Ammonia nitrogen was highest at the highest level of seed inclusion while lactic acid was highest at 60 days of ensiling. Crude protein and tannin contents of the silage increased (p &lt; 0.05) following the increased seed inclusion while there was a reduction as the ensiling duration increased. The total anaerobic bacteria count, total lactobacilli count, and total yeast count of the silage decreased following the increased inclusion of seeds in the silage. As the ensiling duration increased, a reduction in all the silage microbial counts was observed. Inclusion of 25 % of the seeds to 75 % of the grass for silage with ensiling up to 120 days supported improved fermentation characteristics, microbial and crude protein contents as well as a reduction in tannin content which implies that there will not be a detrimental effect on animals that feed on the silage.

Lactobacillus plantarum and propionic acid improve the fermentation quality of high-moisture amaranth silage by altering the microbial community composition.

The objective of this study was to determine the effect of Lactobacillus plantarum (L. plantarum) and propionic acid (PA) on the microbial community and fermentation performance of high-moisture amaranth silage. Amaranth silages were rown without addition (AhGCK) as a control and with L. plantarum JYLP-002 (AhGLP) or propionic acid (AhGPA) and then were opened after 60 days of ensiling to determine the microbial community and fermentation quality. Crude protein (CP) content, lactic acid (LA) content, and lactic acid bacteria (LAB) counts were significantly higher in AhGLP and AhGPA compared with those in AhGCK (p < 0.05). In contrast, pH, acetic acid (AA) content, and yeast and aerobic bacteria counts were significantly lower in AhGLP and AhGPA compared with those in AhGCK (p < 0.05). In addition, propionic acid (PA) levels were markedly higher in AhGPA (p < 0.05). In terms of microbial communities, the silage in the additive groups showed an increased relative abundance of Lactiplantibacillus plantarum and Lentilactobacillus buchneri and a reduced relative abundance of Enterobacter cloacae and Clostridium tyrobutyricum. The abundance of Xanthomonas oryzae was significantly increased in AhGPA, but completely inhibited in the silage supplemented with L. plantarum. Spearman's correlation analysis revealed that Lentilactobacillus buchneri and Levilactobacillus brevis were positively associated with LA and negatively associated with pH. Conversely, Clostridium tyrobutyricum and Enterobacter cloacae were negatively associated with LA, but positively associated with pH and AA content. AA content was inversely correlated with Lentilactobacillus buchneri. Functional prediction analysis showed that LAB dominated the three groups of silage and the silages containing additives had improved carbohydrate and amino acid metabolism compared with the control silage; in particular, the AhGLP group had more heterotypic fermentation processes and a richer metabolic pathway. Furthermore, the epiphytic Lactiplantibacillus plantarum and Lentilactobacillus buchneri could inhibit the reproductive activity of undesirable microorganisms to a certain extent, thus slowing the spoilage process of the silage. In conclusion, L. plantarum can improve fermentation characteristics by modulating the microbial community attached to high-moisture amaranth silage and will prove useful for preserving high-moisture silage.

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.

Improving the quality of Napier grass silage with pyroligneous acid: Fermentation, aerobic stability, and microbial communities.

The presence of undesirable microorganisms in silage always leads to poor fermentation quality and low aerobic stability. Pyroligneous acid (PA), a by-product of biochar production, is known to have strong antimicrobial and antioxidant activities. To investigate the effects of PA on fermentation characteristics, aerobic stability, and microbial communities, Napier grass was ensiled with or without 1 and 2% PA for 30 days and then aerobically stored for 5 days. The results showed that PA application decreased (P < 0.01) the pH value, ammonia nitrogen content, and number of undesirable microorganisms (coliform bacteria, yeasts, and molds) after 30 days of ensiling and 5 days of exposure to air. The temperature of the PA-treated group was stable during the 5-day aerobic test, which did not exceed room temperature more than 2°C. The addition of PA also enhanced the relative abundance of Lactobacillus and reduced that of Klebsiella and Kosakonia. The relative abundance of Candida was higher in PA-treated silage than in untreated silage. The addition of PA decreased the relative abundance of Kodamaea and increased that of Monascus after 5 days of exposure to air. The abundances of Cladosporium and Neurospora were relatively high in 2% PA-treated NG, while these genera were note observed in the control group. These results suggested that the addition of PA could improve fermentation characteristics and aerobic stability, and alter microbial communities of silage.

Characterization and identification of a novel microbial consortium M2 and its effect on fermentation quality and enzymatic hydrolysis of sterile rice straw.

To isolate and enrich lignocellulolytic microbial consortia from yak (Bos grunniens) rumen and evaluate their effects on the fermentation characteristics and enzymatic hydrolysis in rice straw silage. A novel microbial consortium M2 with high CMCase and xylanase activities was enriched and observed to be prone to use natural carbon sources. Its predominant genus was Enterococcus, and most carbohydrate-active enzyme (CAZyme) genes belonged to the glycosyl hydrolases class. The consortium M2 was introduced with or without combined lactic acid bacteria (XA) to rice straw silage for 60days. Inoculating the consortium M2 notably decreased the structural carbohydrate contents and pH of rice straw silages. Treatment that combines consortium M2 and XA resulted in the highest levels of lactic acid and lignocellulose degradation. The consortium M2 alone or combined with XA significantly (p<0.01) increased water-soluble carbohydrates (WSCs), mono- and disaccharides contents compared with the XA silage. Combined addition obviously improved the enzymatic conversion efficiency of rice straw silage with higher glucose and xylose yields (23.39 and 12.91 w/w% DM, respectively). Ensiling pretreatment with the microbial consortium M2 in sterile rice straw improved fermentation characteristics. The combined application of consortium M2 with XA had synergistic effects on promoting the degradation of structural carbohydrates and enzymatic hydrolysis. Rice straw is difficult to ensile because of its low WSC and high structural carbohydrate contents. The microbial consortium M2 identified herein exhibits great potential for degrading fibrous substrates, and their combination with XA provides a faster and more effective synergistic strategy for biorefinery of lignocellulosic biomass.

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.

Effect of Bacillus amyloliquefaciens and Bacillus subtilis on fermentation, dynamics of bacterial community and their functional shifts of whole-plant corn silage

BackgroundBacillus amyloliquefaciens (BA) and Bacillus subtilis (BS) are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals. However, few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling. If the BA and BS inoculants have positive effects on silages, then they could not only improve fermentation characteristics, but also deliver BA or BS viable cells to ruminants, which would play its probiotic effect. Therefore, the objectives of this study were to investigate the effects of BA and BS on the fermentation, chemical characteristics, bacterial community and their metabolic pathway of whole-plant corn silage.ResultsFreshly chopped whole-plant corn was inoculated without or with BA and BS, respectively, and ensiled for 1, 3, 7, 14 and 60 d. Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control, and BA inoculation decreased acetic acid concentrations, whereas BS inoculation decreased fiber contents and increased crude protein (CP) content. Higher water-soluble carbohydrate contents and lower starch contents were observed in BA- and BS-inoculated silages compared with that in control. The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage, which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage. In addition, it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins, and decreased the relative abundances of drug resistance: antimicrobial pathways. We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study. There were no significant differences in bacterial community compositions among the three groups during ensiling. However, BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.ConclusionOur findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.

Extracts of herbs and spices as feed additives mitigate ruminal methane production and improve fermentation characteristics inWest African Dwarf sheep.

The study aims to evaluate the effect of aqueous and methanolic extracts of three herbs, namely, neem (Azadirachta indica), drumstick (Moringa oleifera) and scent (Ocimum gratissimum), and three spices garlic (Allium sativum), ginger (Zingiber officinale) and onion leaflets (Allium cepa) on ruminal methane production and fermentation characteristics. The feed samples (200 mg substrates plus extracts of the selected herbs and spices) were incubated with rumen liquor taken from three mature West African dwarf ewes at 3, 6, 9, 12, 15, 18, 21 and 24 h. The results show that extracts of the selected herbs and spices increased the gas produced, from the insoluble fraction, degradability rate, volume of gas produced at time and time of most rapid change in gas produced. The organic matter digestibility (OMD), metabolizable energy (ME) and short-chain fatty acid (SCFA) contents of aqueous extracts of the selected herbs and spices (1 ml/200 mg substrates samples) were between 32.82 and 71.34 g/100 g OM, 4.10 and 10.25 MJ/kg DM and 0.28 and 1.31 μmol, respectively. Furthermore, the OMD, ME and SCFA contents of methanolic extracts of the selected herbs and spices (1 ml/200 mg substrates samples) were between 32.82 and 99.50 g/100 g OM, 4.10 and 14.37 MJ/kg DM and 0.28 and 2.07 μmol, respectively. Methane produced from the methanolic extracts of the herbs and spices highly differed (P < 0.05). This study suggests that extracts of the selected herbs and spices have the potential to affect rumen fermentation and also to reduce the methane production in sheep.

Ensiling alfalfa and alfalfa–bermudagrass with ferulic acid esterase‐producing microbial inoculants

AbstractNew silage inoculants contain a bacterial strain that produces ferulic acid esterase (FAE), which may facilitate lignin breakdown and increase the ensiled forage's digestibility. The objective of this study was to evaluate the efficacy of a FAE‐producing microbial inoculant for improving fermentation characteristics, nutritive value, and digestibility of alfalfa (Medicago sativa L.) (ALF) or alfalfa–bermudagrass [Cyondon dactylon (L.) Pers.] (ABG) silage. This study was conducted at the University of Georgia Tifton Campus in Tifton, GA, and the J. Phil Campbell Research and Extension Center in Watkinsville, GA, on 0.25 acres of previously established ‘Bulldog 805′ alfalfa (Tifton) and a hybrid bermudagrass interseeded with Bulldog 505 alfalfa (Watkinsville). Forage was harvested twice during the growing season at 10% bloom of the alfalfa to simulate lignin content differences during the growing season. Harvested forage was treated with one of three treatments [FAE‐producing microbial inoculant (MI + FAE), a heterofermentative microbial forage inoculant (MI), or an untreated water control] before being packed into miniature silos to undergo a 60‐d fermentation. After a fermentation period, forage was analyzed for fermentation characteristics, nutritive value, and digestibility parameters. The inoculant treatment tended (P &lt; .1) to affect total volatile fatty acid production in alfalfa; ABG was unaffected (P = .91). Inoculant treatment also did not affect in vitro dry matter digestibility of either forage (P = .22 and .33 for ALF and ABG, respectively). The MI + FAE treatment did not improve fermentation characteristics, nutritive value, or digestibility parameters compared with the MI inoculant.

Deletion of pgi gene in E. coli increases tolerance to furfural and 5-hydroxymethyl furfural in media containing glucose\u2013xylose mixture

BackgroundFurfural and 5-hydroxymethyl furfural (5-HMF) are key furan inhibitors that are generated due to breakdown of lignocellulosic sugars at high temperature and acidic treatment conditions. Both furfural and 5-HMF act in a synergistic manner to inhibit microbial metabolism and resistance to both is a desirable characteristic for efficient conversion of lignocellulosic carbon to ethanol. Genetic manipulations targeted toward increasing cellular NADPH pools have successfully imparted tolerance against furfural and 5-HMF. In present study, deletion of pgi gene as a strategy to augment carbon flow through pentose phosphate pathway (PPP) was studied in ethanologenic Escherichia coli strain SSK101 to impart tolerance towards either furfural or 5-HMFor both inhibitors together.ResultsA key gene of EMP pathway, pgi, was deleted in an ethanologenic E. coli strain SSK42 to yield strain SSK101. In presence of 1 g/L furfural in minimal AM1 media, the rate of biomass formation for strain SSK101 was up to 1.9-fold higher as compared to parent SSK42 strain, and it was able to clear furfural in half the time. Tolerance to inhibitor was associated with glucose as carbon source and not xylose, and the tolerance advantage of SSK101 was neutralized in LB media. Bioreactor studies were performed under binary stress of furfural and 5-HMF (1 g/L each) and different glucose concentrations in a glucose–xylose mixture with final sugar concentration of 5.5%, mimicking major components of dilute acid treated biomass hydrolysate. In the mixture having 6 g/L and 12 g/L glucose, SSK101 strain produced ~ 18 g/L and 20 g/L ethanol, respectively. Interestingly, the maximum ethanol productivity was better at lower glucose load with 0.46 g/(L.h) between 96 and 120 h, as compared to higher glucose load where it was 0.33 g/(L.h) between 144 and 168 h. Importantly, parent strain SSK42 did not exhibit significant metabolic activity under similar conditions of inhibitor load and sugar concentration.ConclusionsE. coli strain SSK101 with pgi deletion had enhanced tolerance against both furfural and 5-HMF, which was associated with presence of glucose in media. Strain SSK101 also had improved fermentation characteristics under both hyperosmotic as well as binary stress of furfural and 5-HMF in media containing glucose–xylose mixture.

Use of Fresh Scotta Whey as an Additive for Alfalfa Silage

Scotta is a dairy industry waste obtained by ricotta cheese production. Because of its high availability and its high lactose content, scotta could be used as an additive to improve fermentation characteristics of alfalfa silage. Silage samples were obtained for 2 years from an alfalfa second cut, collecting the forage at three growth stages: mid bud (MB), early flowering (EF), and late flowering (LF). After wilting the forage at 38% dry matter (DM), four scotta doses were added (0, 75, 150, and 300 g/kg fresh forage) and the main chemical and microbiological characteristics were evaluated after 3, 13, and 90 days of ensiling (DOE). The lowest pH (4.3) was recorded in the EF and LF growth stages, after 90 DOE and with the highest scotta dose (300 g/kg fresh forage). After 90 DOE, the concentration of the main spoilage microorganisms and clostridial spore loads was always negligible. The addition of scotta decreased pH and fiber fractions, increased the relative feed value, and had no effect on the crude protein concentration or the total digestible nutrients. Therefore, the scotta can be successfully used as an additive to improve the fermentation characteristics of alfalfa silage.

A comparison of whole cell directed evolution approaches in breeding of industrial strain of Saccharomyces cerevisiae.

To reduce the fermentation cost in very high gravity fermentations of ethanol using Saccharomyces cerevisiae, whole cell directed evolution approaches were carried out. The methods used included cell ploidy manipulation, global transcription machinery engineering and genome shuffling. Ethanol production by the four methods was improved compared with the control. Notably, the ethanol yield of a strain constructed by genome shuffling was enhanced by up to 11 % more than the control reaching 120 g ethanol/l in 35 h using a very high gravity fermentation with 300 g glucose/l. Genome shuffling can create strains with improved fermentation characteristics in very high gravity fermentations.

Effect of Crude Protein Levels in Concentrate and Concentrate Levels in Diet on In vitro Fermentation.

The effect of concentrate mixtures with crude protein (CP) levels 10%, 13%, 16%, and 19% and diets with roughage to concentrate ratios 80:20, 60:40, 40:60, and 20:80 (w/w) were determined on dry matter (DM) and organic matter (OM) digestibility, and fermentation metabolites using an in vitro fermentation technique. In vitro fermented attributes were measured after 4, 24, and 48 h of incubation respectively. The digestibility of DM and OM, and total volatile fatty acid (VFA) increased whereas pH decreased with the increased amount of concentrate in the diet (p<0.001), however CP levels of concentrate did not have any influence on these attributes. Gas production reduced with increased CP levels, while it increased with increasing concentrate levels. Ammonia nitrogen (NH3-N) concentration and microbial CP production increased significantly (p<0.05) by increasing CP levels and with increasing concentrate levels in diet as well, however, no significant difference was found between 16% and 19% CP levels. Therefore, 16% CP in concentrate and increasing proportion of concentrate up to 80% in diet all had improved digestibility of DM and organic matter, and higher microbial protein production, with improved fermentation characteristics.

Short- and long-time effects of multispecies lactic acid bacteria inoculant on fermentation characteristics and aerobic stability of corn silages at different maturities and frost killed corn

The objective of this experiment was to evaluate the short- and long-time effects of a multispecies lactic acid bacteria (LAB) inoculant on biochemical characteristics of corn silages at hard dough (HD, 253.1 g DM kg−1), one-third milk line (ML, 293.7 g DM kg−1), and one-third milk line with a killing frost (FKML, 297.6 g DM kg−1) maturity stages. The crops were ensiled in laboratory silos with (1.5 × 105 cfu g−1 of fresh forage) or without Lactisil Maize. Concentrations of dry matter and neutral detergent fiber, value of pH, and population of fungi were higher in ML and FKML crops compared with HD (p < 0.01). In contrast, lower water-soluble carbohydrate and crude protein concentrations and lower populations of epiphytic LAB were measured in ML and FKML crops (p < 0.01). Frosting reduced population of LAB and increased yeast number (p < 0.01) but did not affect chemical composition. Preservation of ensilage for 160 days compared with 42 days increased concentration of lactic acid and ratio of lactic acid to acetic acid in HD silage. Extensive homolactic fermentation was occurred in response to inoculation in all treated silages at first period of ensiling (42 days). However, the current inoculant could dominate heterofermentative LAB over homofermentative LAB during the latter part of the ensiling period (160 days). Application of this inoculant for ensiling corn crop will improve fermentation characteristics but aerobic stability of inoculant-received silages will be improved after long-time preservation.

죽염 된장의 발효 특성 및 기능성 증진 효과

The aim of this study is carried out to evaluate the fermentation characteristics and increased functionality when doenjang was prepared with bamboo salts. Grain type mejus were fermented with mixed starter cultures of Aspergillus oryzae, Bacillus subtilis, and Lactococcus lactis. These mejus were mixed with different kinds of saltspurified salt (PD), sea salt (SD), one-time baked bamboo salt (1×BD), three-time baked bamboo salt (3×BD), and nine-time baked bamboo salt (9×BD)－ when doenjangs were prepared. For doenjang fermentation period of 8 weeks at 37°C, the fermentation characteristics of all the groups were compared. The amino type nitrogen content and enzyme activities (protease and α-amylase) in the samples were significantly increased. In DPPH radical scavenging activities and hydroxyl radical scavenging activities, 9×BD (47% and 69%) showed the highest scavenging activities compared to PD (40% and 49%), SD (42% and 57%), 1×BD (42% and 64%) and 3×BD (45% and 65%) (P<0.05). The anticancer effects of doenjang in HT-29 cancer cells indicated all the groups, especially doenjang prepared with bamboo salts were higher than the others (P<0.05). Apoptosis related genes of Bax and Bcl-2, as well as inflammation related genes of iNOS and COX-2 were regulated by the treatment of doenjangs in HT-29 cancer cells. SD, 1×BD, 3×BD, and 9×BD increased the expression level of Bax and decreased the expression level of Bcl-2, iNOS, and COX-2. These results suggest that sea salt and bamboo salt especially bamboo salt could improve fermentation characteristics and functionality of doenjang and play an important role in regulating apoptosis and inflammation related genes in cancer cells.

Effects of homo-fermentative bacterial inoculants on fermentation characteristics and nutritive value of low dry matter corn silage

Summary This study was conducted to evaluate the effects of inoculation of homo-fermentative lactic acid bacteria (LAB) on ensiling characteristics and nutritive value of low dry matter corn silage (LDMCS). Corn forage was harvested at milk stage (22.8 ± 0.9% DM), chopped at theoretical length of cut (TLC) 2.5 cm, and stored in eighteen 3.8 L mini silos for each treatment. The following treatments were used, 1) control (uninoculated), 2) ecosyl (treated with ecosyl TM corn silage inoculants containing Lactobacillus plantarum), and 3) biotal (treated with biotal TM corn silage inoculants containing Lactobacillus plantarum, Pediococcus pentosaceus and Propionibacter freudenreichii). Triplicate silos for each treatment were opened and sampled for chemical analyses after 3, 6, 12, 16, 21 and 90 days of ensiling. Neither ecosyl nor biotal improved fermentation characteristics of LDMCS compared to the control silage. Neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), water soluble carbohydrate (WSC) contents and lactic acid (LA) concentration were not affected significantly by inoculants (P>0.05). Acetic acid concentration of control silages was higher; however, ethanol concentration was lower than the other silages. Biotal treated silages had the highest ammonia-N (NH3-N) concentrations compared to the control (P<0.05). In vitro dry matter disappearance (IVDMD) of control silage was higher than treated silages (P<0.05). In conclusion, the results showed that homo-fermentative LAB inoculants used in this experiment did not improve the fermentation characteristics and nutritive value of LDMCS.

Laboratory evaluation of absorbents and additives on the fermentation quality of potato hash

This study was conducted to determine the ensiling potential of potato hash (PH) with poultry litter (PL) and hay as absorbents, and whey and molasses as additives. Mixtures of 800 g/kg PH and 200 g/kg of either PL or hay were produced and treated with no additive, whey and molasses. The experiment was conducted in a 2 absorbents × 3 additives factorial design. Mixtures were ensiled in 1.5 L anaerobic jars, and sampling was done on days 0, 4, 10, 20, 40, 60, and 90 for the determination of fermentation quality and nutritive value. Further, an aerobic stability test was done on day 90 by exposing silage to air for 5 days. Ensiling PH with hay compared to PL resulted in a better quality silage as indicated by (P < 0.05) improved fermentation characteristics and chemical composition. Although, the addition of PL significantly increased (P < 0.05) the crude protein (CP) and ash contents in PH silage, fermentation, and the aerobic stability of silage was poor and could influence animal performance negatively. It seems that whey and molasses were effective in improving the in vitro organic matter digestibility (IVOMD) and fermentation characteristics of PH. Further studies are needed to elucidate these effects on animal performance. Key words: Aerobic stability, by-products, potato hash, energy, molasses, whey.