Effects of calcium propionate on the fermentation quality and aerobic stability of alfalfa silage

Dong, Zhihao,Yuan, Xianjun,Wen, Aiyou,Desta, Seare T.,Shao, Tao Asian Australasian Association of Animal Productio 2017 Animal Bioscience Vol.30 No.9

Objective: To assess the potency of calcium propionate (CAP) used as silage additive, an experiment was carried out to evaluate the effect of CAP on the nitrogen transformation, fermentation quality and aerobic stability of alfalfa silages. Methods: Alfalfa was ensiled with four levels of CAP (5, 10, 15, and 20 g/kg of fresh weight [FW]) in laboratory silos for 30 days. After opening, the silages were analyzed for the chemical and microbiological characteristics, and subjected to an aerobic stability test. Results: The increasing proportion of CAP did not affect pH, lactic acid (LA) concentrations and yeast counts, while linearly decreased counts of enterobacteria (p = 0.029), molds (p<0.001) and clostridia (p<0.001), and concentrations of acetic acid (p<0.001), propionic acid (p<0.001), butyric acid (p<0.001), and ethanol (p = 0.007), and quadratically (p = 0.001) increased lactic acid bacteria counts. With increasing the proportion of CAP, the dry matter (DM) loss (p<0.001), free amino acid N (p<0.001), ammonia N (p = 0.004), and non-protein N (p<0.001) contents were linearly reduced, whereas DM (p = 0.048), water soluble carbohydrate (p<0.001) and peptide N (p<0.001) contents were linearly increased. The highest Flieg's point was found in CAP10 (75.9), represented the best fermentation quality. All silages treated with CAP improved aerobic stability as indicated by increased stable hours compared with control. Conclusion: The addition of CAP can suppress the undesirable microorganisms during ensiling and exposure to air, thereby improving the fermentation quality and aerobic stability as well as retarding the proteolysis of alfalfa silage. It is suggested that CAP used as an additive is recommended at a level of 10 g/kg FW.

Evaluating fermentation quality, in vitro digestibility and aerobic stability of a total mixed ration ensiled with different additives on Tibet plateau

Dong, Zhihao,Wang, Siran,Zhao, Jie,Li, Junfeng,Liu, Qinhua,Bao, Yuhong,Shao, Tao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.2

Objective: To investigate the improvement in utilization efficiency of total mixed ration (TMR) on Tibetan plateau, TMR were ensiled with different additives. Methods: A total of 150 experimental silos were prepared in a completely randomized design to evaluate the six treatments: i) control (without additive), ii) Lactobacillus buchneri (L. buchneri), iii) acetic acid, iv) propionic acid, v) 1,2-propanediol; and vi) 1-propanol. After 90 days of ensiling, silos were opened for fermentation quality and in vitro analysis, and then subjected to an aerobic stability test for 14 days. Results: Treating with L. buchneri, acetic acid, 1,2-propanediol and 1-propanol decreased propionic acid contents and yeast number, whereas increased (p<0.05) pH, acetic acid and ethanol contents in the fermented TMR. Despite increased dry matter (DM) loss in the TMRs treated with 1,2-propanediol and 1-pronanol, additives did not affect (p>0.05) all in vitro parameters including gas production at 24 h (GP24), GP rate constant, potential GP, in vitro DM digestibility and in vitro neutral detergent fibre digestibility. All additives improved the aerobic stability of ensiled TMR to different extents. Specially, aerobic stability of the ensiled TMR were substantially improved by L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol, indicated by stable pH and lactic acid content during the aerobic stability test. Conclusion: L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol had no adverse effect on in vitro digestibility, while ensiling TMR with the additives produced more acetic acid and ethanol, subsequently resulting in improvement of aerobic stability. There is a potential for some fermentation boosting additives to enhance aerobic stability of fermented TMR on Tibetan plateau.

Effects of additives on the fermentation quality, in vitro digestibility and aerobic stability of mulberry (Morus alba L.) leaves silage

Dong Zhihao,Wang Siran,Zhao Jie,Li Junfeng,Shao Tao 아세아·태평양축산학회 2020 Animal Bioscience Vol.33 No.8

Objective: To explore feed resources capable of replacing regular poor-quality fodder, this study was conducted to evaluate the effects of additives on the fermentation quality, in vitro digestibility and aerobic stability of mulberry leaves silage. Methods: The mulberry leaves were ensiled either untreated (control) or treated with 1×106 cfu/g fresh matter Lactobacillus plantarum (L), 1% glucose (G), 3% molasses (M), a combination of 1% glucose and Lactobacillus plantarum (L+G), and a combination of 3% molasses and Lactobacillus plantarum (L+M). The fermentation quality and chemical composition were analyzed after 7, 14, 30, and 60 d, respectively. The 60-d silages were subjected to an aerobic stability test and fermented with buffered rumen fluid to measure the digestibility. Results: Inoculating lactic acid bacteria (LAB) resulted in more rapid increase in lactic acid concentrations and decline in pH of mulberry leaves silage as compared control. Higher acetic acid and lower ethanol and ammonia nitrogen concentrations (p<0.05) were observed in the LAB-inoculated silages as opposed to control during ensiling. The LAB-inoculated silages contained lower water-soluble carbohydrates compared with control during the first 14 d of ensiling, and lower neutral detergent fibre (p<0.05) concentrations as compared with non-LAB inoculated silages. Adding molasses alone increased (p<0.05) the digestibility of dry matter (DM). The aerobic stability of mulberry leaves silage was increased by LAB inoculation, whereas decreased by adding glucose or molasses. Conclusion: The LAB inoculation improved fermentation quality and aerobic stability of mulberry leaves silage, while adding glucose or molasses failed to affect the fermentation and impaired the aerobic stability. Inoculating LAB alone is recommended for mulberry leaves especially when ensiled at a relatively high DM.

Comparison of nitrogen transformation dynamics in non-irradiated and irradiated alfalfa and red clover during ensiling

Zhihao Dong,Junfeng Li,Lei Chen,Xianjun Yuan,Tao Shao 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.10

Objective: To study the contribution of plant enzyme and microbial activities on protein degradation in silage, this study evaluated the nitrogen transformation dynamics during ensiling of non- and irradiated alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.). Methods: Alfalfa and red clover silages were prepared and equally divided into two groups. One group was exposed to γ-irradiation at a recommended dosage (25 Gky). Therefore, four types of silages were produced: i) non-irradiated alfalfa silage; ii) irradiated alfalfa silage; iii) non-irradiated red clover silage; and iv) irradiated red clover silage. These silages were opened for fermentation quality and nitrogen components analyses after 1, 4, 8, and 30 days, respectively. Results: The γ-irradiation successfully suppressed microbial activity, indicated by high pH and no apparent increases in fermentation end products in irradiated silages. All nitrogen components, except for peptide-N, increased throughout the ensiling process. Proteolysis less occurred in red clover silages compared with alfalfa silages, indicated by smaller (p<0.05) increment in peptide-N and free amino acid N (FAA-N) during early stage of ensiling. The γ-irradiation treatment increased (p<0.05) peptide-N and FAA-N in alfalfa silage at day 1, whereas not in red clover silage; these two nitrogen components were higher (p<0.05) between day 4 and day 30 in non-irradiated silages than the irradiated silages. The ammonia nitrogen and non-protein nitrogen were highest in non-irradiated alfalfa silage and lowest in irradiated red clover silage after ensiling. Conclusion: The result of this study indicate that red clover and alfalfa are two forages varying in their nitrogen transformation patterns, especially during early stages of ensiling. Microbial activity plays a certain role in the proteolysis and seems little affected by the presence of polyphenol oxidase in red clover compared with alfalfaa.

Sb-Fe bimetallic non-aqueous phase desulfurizer for efficient absorption of hydrogen sulfide: A combined experimental and DFT study

Zhihao Liu,Kui Qiu,Yu Dong,Zhaobo Jin,Luwei Liu,Jirong Wu 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.12

A non-aqueous phase (Sb/Fe/NMP) desulfurization system for the removal of hydrogen sulfide from naturalgas was constructed by introducing SbCl3 and FeCl3 in a specific ratio into N-methylpyrrolidone (NMP). The desulfurizingagent and its sulfur product were characterized, and the absorption pattern of H2S by the system wasinvestigated by static desulfurization experiments. The results indicate that the desulfurizer’s sulfur capacity can reach16 g/L at room temperature and pressure, and that adding the optimum amount of water and appropriate temperatureincrease can assist to increase desulfurization efficiency. The system maintained a sulfur capacity level of more than90% of the initial sulfur capacity after five consecutive desulfurization-regeneration cycles. XRD and XPS spectrogramrevealed that the regenerated solid product was high purity sulfur. Sb3+ is a key component to ensure the effectiveabsorption of H2S. The presence of a moderate amount of Fe3+ can oxidize and absorb small amounts of H2S and promotethe oxidative regeneration of the system. In addition, we combined the obtained experimental data with densityflooding theory (DFT) theoretical calculations to show that the effective coordination of Sb(III) with HS in the NMPenvironment is the main reason for the effective absorption of H2S by the desulfurizer. NMP is not involved in thecoordination absorption process of hydrogen sulfide.

Analysis and Suppression of Mutual Inductive Couplings of the CM EMI Filter in Motor Drive

Zhihao Fang,Dong Jiang,Zaidong Hu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

This paper gives an analysis of mutual inductive couplings of the CM EMI filter in motor drive. First, the high-frequency model of L-C EMI filter is proposed, then, equivalent decoupling circuits are established based on the method of transferring controlled voltage source. It is concluded by calculation that some mutual inductive couplings have an effect on the transfer gain of EMI filter in the whole frequency spectrum of EMI current. While some mutual inductive couplings influence the transfer gain only at high frequency range. Finally, in order to drop the EMI current below the standard, the combination of an optimized EMI filter and an advanced method are adopted.

Enhanced adsorption capacity of dyes by surfactant-modified layered double hydroxides from aqueous solution

Bei Zhang,Zhihao Dong,Dejun Sun,Tao Wu,Yujiang Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.49 No.-

The utilization of organo-modified layered double hydroxides with anionic surfactants (organo-LDHs) asadsorbents were successfully carried out to remove various synthetic dyes from aqueous solution. Intercalation of anionic surfactants changed the surface properties of MgAl-LDH from hydrophilic tohydrophobic, and a charge inversion occurred with increasing the length of surfactant chains. Suchchanges in the surface properties of the organo-LDHs were important. Experimental data shown that theSNS-modified MgAl-LDH could be used as a broad-spectrum adsorbent to effectively remove anionic,non-ionic, and cationic dyes from aqueous solution.

Effects of lactic acid bacteria and molasses on fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro ruminal fermentation of rice straw silage

Jie Zhao,Zhihao Dong,Junfeng Li,Lei Chen,Yunfeng Bai,Yushan Jia,Tao Shao 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.6

Objective: This study was to evaluate the fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro gas production of rice straw ensiled with lactic acid bacteria and molasses. Methods: Fresh rice straw was ensiled in 1-L laboratory silos with no additive control (C), Lactobacillus plantarum (L), molasses (M) and molasses+Lactobacillus plantarum (ML) for 6, 15, 30, and 60 days. After storage, the silages were subjected to microbial and chemical analyses as well as the further in vitro fermentation trial. Results: All additives increased lactic acid concentration, and reduced pH, dry matter (DM) loss and structural carbohydrate content relative to the control (p<0.05). The highest organic acid and residual sugar contents and lignocellulose reduction were observed in ML silage. L silage had the highest V-score with 88.10 followed by ML silage. L and ML silage improved in vitro DM digestibility as compared with other treatments, while in vitro neutral detergent fibre degradability (IVNDFD) was increased in M and ML silage (p<0.05). M silage significantly (p<0.05) increased propionic acid (PA) content and decreased butyric acid content and acetic acid/PA as well as 72-h cumulative gas production. Conclusion: The application of ML was effective for improving both the fermentation quality and in vitro digestibility of rice straw silage. Inclusion with molasses to rice straw could reduce in vitro ruminal gas production.

Mathematical Modeling of Drying Kinetics for Pulp Sheet Based on Fick’s Second Law of Diffusion

Lingbo Kong,Xing Yang,Zhihao Hou,Jixian DONG 한국펄프·종이공학회 2020 펄프.종이기술 Vol.52 No.2

In this study, we investigated the drying characteristics for pulp sheet at different hot air temperature (80, 90, and 100℃). The drying kinetics were modeled using one- to five-term solutions of Fick’s second law of diffusion at different drying conditions. It was found that these models underestimated the initial drying stages and overestimated the final drying stages. Meanwhile, the values of the diffusion coefficient tended to stabilize when the series terms more than three. In order to improve the accuracy of the mathematical models, the modified one- to three-term models were also used to describe the drying kinetics. The results showed that modeling data was agreed with the experiment data better than the series solution models based on Fick’s second law of diffusion. Besides, the accuracy improved dramatically as the terms of the model increased. The minimum diffusion coefficient was 0.996 for the modified three-term model. It was concluded that the modified model could simulate the pulp sheet drying process under the conditions studied.

Characteristics of isolated lactic acid bacteria and their effects on the silage quality

Siran Wang,Xianjun Yuan,Zhihao Dong,Junfeng Li,Gang Guo,Yunfeng Bai,Junyu Zhang,Tao Shao 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.6

Objective: Four lactic acid bacteria (LAB) strains isolated from common vetch, tall fescue and perennial ryegrass on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass (Lolium multiflorum Lam.) silage were studied. Methods: The four isolated strains and one commercial inoculant (G, Lactobacillus plantarum MTD-1) were evaluated using the acid production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. The five LAB strains were added to Italian ryegrass for ensiling at three different temperatures (10°C, 15°C, and 25°C). Results: All isolated strains (LCG3, LTG7, I5, and LI3) could grow at 5°C to 20°C, pH 3.0 to 8.0 and NaCl (3.0%, 6.5%). Strains LCG3, LTG7, I5, and LI3 were identified as Lactobacillus plantarum, Pediococcus acidilactici, Lactobacillus paraplantarum, and Lactobacillus casei by sequencing 16S rDNA, respectively. All LAB inoculants significantly (p<0.05) increased lactic acid (LA) contents and ratios of lactic acid to acetic acid, and reduced pH and ammonia nitrogen/ total nitrogen (AN/TN) compared with uninoculated silages at various temperatures (10°C, 15°C, and 25°C). Compared to the commercial inoculant G, I5, and LI3 showed similar effects on improving the silage quality of Italian ryegrass at 10°C and 15°C, indicated by similar pH, LA content and AN/TN. Conclusion: All inoculants could improve the silage fermentation quality at various temperatures (10°C, 15°C, and 25°C). At the temperature of 10°C and 15°C, strain I5 and LI3 had similar effects with the commercial inoculant G on improving the silage quality of Italian ryegrass.