• Applied Biological Chemistry
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• v.12
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• pp.57-67
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• 1969

1) Many bacterial strains identified as Bacillus megeterium, Bacillus subtilis and Bacillus licheniformis were aboundantly found in summer jokal kimchi, but the most dominant strains in summer kimchi were Lactobacillus plantarum and Loctobacllus buchneri. 2) Bacillus groups found in kimchi were sensitive in a low concentration of AF-2, but groups of lactic acid bacteria were resistant to a high concentration of AF-2. 3) Allowable concentration of AF-2 in Korean kimchi is less than 10 p.p.m. 4) AF-2 was not suitable for the juicy kimchi as a preservative because the color of juicy kimchi was somewhat changed into orange red when 10 p.p.m. of AF-2 was added. 5) High concentration of AF-2 leads the hetero-fermentation of kimchi bacteria to the homofermentation. 6) Microflora of kimchi was influenced even in the concentration of 10 p.p.m. but it was impossible to check the acidification of kimchi in summer with 50 p.p.m. concentration of AF-2. 7) About 25% of AF-2 was consumed in kimchi fermentation for day at $23^{\circ}-25^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1528-1539
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• 2019

Objective: To evaluate the effects on microbial diversity and biochemical parameters of gradually increasing temperatures, from $5^{\circ}C$ to $25^{\circ}C$ on corn silage which was previously fermented at ambient or low temperature. Methods: Whole-plant corn silage was fermented in vacuum bag mini-silos at either $10^{\circ}C$ or $20^{\circ}C$ for two months and stored at $5^{\circ}C$ for two months. The mini-silos were then subjected to additional incubation from $5^{\circ}C$ to $25^{\circ}C$ in $5^{\circ}C$ increments. Bacterial and fungal diversity was assessed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiling and biochemical analysis from mini-silos collected at each temperature. Results: A temperature of $10^{\circ}C$ during fermentation restricted silage fermentation compared to fermentation temperature of $20^{\circ}C$. As storage temperature increased from $5^{\circ}C$ to $25^{\circ}C$, little changes occurred in silages fermented at $20^{\circ}C$, in terms of most biochemical parameters as well as bacterial and fungal populations. However, a high number of enterobacteria and yeasts (4 to $5\;log_{10}$ colony forming unit/g fresh materials) were detected at $15^{\circ}C$ and above. PCR-DGGE profile showed that Candida humilis predominated the fungi flora. For silage fermented at $10^{\circ}C$, no significant changes were observed in most silage characteristics when temperature was increased from $5^{\circ}C$ to $20^{\circ}C$. However, above $20^{\circ}C$, silage fermentation resumed as observed from the significantly increased number of lactic acid bacteria colonies, acetic acid content, and the rapid decline in pH and water-soluble carbohydrates concentration. DGGE results showed that Lactobacillus buchneri started to dominate the bacterial flora as temperature increased from $20^{\circ}C$ to $25^{\circ}C$. Conclusion: Temperature during fermentation as well as temperature during storage modulates microorganism population development and fermentation patterns. Silage fermented at $20^{\circ}C$ indicated that these silages should have lower aerobic stability at opening because of better survival of yeasts and enterobacteria.

• Animal Bioscience
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• v.35 no.12
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• pp.1871-1880
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• 2022

Objective: The primary goal was to identify the effectiveness of chemical or biological additives in delaying the deterioration of early-harvested wilted rye silage after exposure to air. Methods: Rye harvested as a whole plant at the early heading stage was wilted for 24 h. The wilted forage was divided into treatments including sodium diacetate (SDA) at 3 (SDA3) and 6 g/kg (SDA6), Lactobacillus plantarum (LP), L. buchneri (LB), or their equal mixture (LP+LB) at 1×10⁶ colony-forming unit/g fresh matter. Results: After 60 d of conservation in 20-L silos, lactic acid was greater in LP and LP+LB silages than other treatments (102 vs 90.2 g/kg dry matter [DM]). Acetic acid was greatest in SDA6 (32.0 g/kg DM) followed by LB (26.1 g/kg DM) and was lowest in LP treatment (4.73 g/kg DM). Silage pH was lower with microbial inoculation and the lowest and highest values were observed in LP and untreated silages, respectively. After 60 d, neutral detergent fiber concentration was lowest in SDA6 silages, resulting in the greatest in vitro DM digestibility (846 g/kg DM). Aerobic stability was longest in SDA6 (176 h) followed by LB treatment (134 h). Instability after aerobiosis was greatest in LP silages (68 h), about 8 h less than untreated silages. After aerobic exposure, yeast and mold numbers were lowest in SDA6 silages, resulting in DM loss minimization. Exhaustion of acetic acid and lactic acid after aerobic exposure was lowest with SDA6 but greatest with untreated and LP silages. Conclusion: Treatment of early-cut wilted rye forage with SDA at 6 g/kg resulted in silages with higher feeding value and fermentation quality, and substantially delayed deterioration after aerobic exposure, potentially qualifying SDA at this load for promotion of silage quality and delaying aerobic spoilage of early-harvested (low DM) rye forage.

• Animal Bioscience
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• v.36 no.5
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• pp.720-730
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• 2023

Objective: This study investigated the effects of corn silage as a source of microbial inoculant containing antifungal and carboxylesterase-producing bacteria on fermentation, aerobic stability, and nutrient digestibility of fermented total mixed ration (FTMR) with different energy levels. Methods: Corn silage was used as a bacterial source by ensiling for 72 d with an inoculant mixture of Lactobacillus brevis 5M2 and L. buchneri 6M1 at a 1:1 ratio. The corn silage without or with inoculant (CON vs MIX) was mixed with the other ingredients to formulate for low and high energy diets (LOW vs HIGH) for Hanwoo steers. All diets were ensiled into 20 L mini silo (5 kg) for 40 d in quadruplicate. Results: The MIX diets had lower (p<0.05) acid detergent fiber with higher (p<0.05) in vitro digestibilities of dry matter and neutral detergent fiber compared to the CON diets. In terms of fermentation characteristics, the MIX diets had higher (p<0.05) acetate than the CON diets. The MIX diets had extended (p<0.05) lactic acid bacteria growth at 4 to 7 d of aerobic exposure and showed lower (p<0.05) yeast growth at 7 d of aerobic exposure than the CON diets. In terms of rumen fermentation, the MIX diets had higher (p<0.05) total fermentable fraction and total volatile fatty acid, with lower (p<0.05) pH than those of CON diets. The interaction (p = 0.036) between inoculant and diet level was only found in the immediately fermentable fraction, which inoculant was only effective on LOW diets. Conclusion: Application of corn silage with inoculant on FTMR presented an antifungal effect by inhibiting yeast at aerobic exposure and a carboxylesterase effect by improving nutrient digestibility. It also indicated that fermented feedstuffs could be used as microbial source for FTMR. Generally, the interaction between inoculant and diet level had less effect on this FTMR study.