scholarly journals Effect of Acetic Acid Concentration and Mixed Culture of Lactic Acid Bacteria on Producing Bacterial Cellulose Using Gluconacetobacter sp. gel_SEA623-2

2014 ◽  
Vol 50 (3) ◽  
pp. 227-232
Author(s):  
Kyung min Kim ◽  
Jihyeon Kim ◽  
Kyong Wol Yang
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bacterial Cellulose ◽  
Mixed Culture ◽  
Acid Concentration ◽  
Acetic Acid Concentration

scholarly journals Acetic Acid Increases Stability of Silage under Aerobic Conditions

2003 ◽  
Vol 69 (1) ◽  
pp. 562-567 ◽  
Author(s):  
H. Danner ◽  
M. Holzer ◽  
E. Mayrhuber ◽  
R. Braun
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acid Concentration ◽  
Butyric Acid ◽  
Lactobacillus Brevis ◽  
Acetic Acid Concentration ◽  
Aerobic Conditions ◽  
Lactobacillus Buchneri ◽  
Aerobic Stability

ABSTRACT The effects of various compounds on the aerobic stability of silages were evaluated. It has been observed that inoculation of whole-crop maize with homofermentative lactic acid bacteria leads to silages which have low stability against aerobic deterioration, while inoculation with heterofermentative lactic acid bacteria, such as Lactobacillus brevis or Lactobacillus buchneri, increases stability. Acetic acid has been proven to be the sole substance responsible for the increased aerobic stability, and this acid acts as an inhibitor of spoilage organisms. Therefore, stability increases exponentially with acetic acid concentration. Only butyric acid has a similar effect. Other compounds, like lactic acid, 1,2-propanediol, and 1-propanol, have been shown to have no effect, while fructose and mannitol reduce stability.

scholarly journals Ensiling corn silage with different levels of a multi-species lactic acid bacteria inoculant

2014 ◽  
Vol 54 (2) ◽  
pp. 165
Author(s):  
H. Mohammadzadeh ◽  
M. Khorvash ◽  
G. R. Ghorbani
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acid Concentration ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Lactic Acid Concentration ◽  
Fermentation Products ◽  
Neutral Detergent Fibre ◽  
Aerobic Stability

A multi-species lactic acid bacterial inoculant (Lactisil maize, LM) was applied to whole-crop corn at different maturities in laboratory silos, to evaluate its effects on biochemical characteristics and aerobic stability. The corn crop was harvested at hard dough (HD, 253.1 g/DM kg), one-third milkline (ML, 293.7 g/DM kg) and one-third milkline with a killing frost (MLF, 297.6 g/DM kg). Crops were chopped to a 2.5-cm theoretical cut length, subsampled and treated with two levels of inoculant (LB1 = 1.5 × 105 cfu/g forage, LB2 = 3 × 105 cfu/g forage) or untreated (WO). The chemical composition of MLF crops was very similar to that of ML crops. However, lower (P < 0.01) numbers of lactic acid bacteria and higher numbers of yeast were enumerated in MLF than in ML crops. Higher percentages of DM and neutral detergent fibre and higher pH, but lower (P < 0.01) concentrations of water soluble carbohydrate and crude protein were measured in ML and MLF crops than in HD crops. Application of the inoculant increased (P < 0.01) concentrations of volatile fatty acids, neutral detergent fibre and acid detergent fibre in silages. Lactic acid concentration increased (P < 0.01) in HD treatments with an increasing level of inoculant. In contrast, the highest (P < 0.01) lactic acid concentration was measured in LB1 treatment compared with WO and LB2 in ML and MLF silages. Silages prepared from ML and MLF crops had higher (P < 0.01) lactic and acetic acid concentrations but lower (P < 0.01) butyric acid concentrations than did those prepared from HD. The pH in LB1 and LB2 silages was higher (P < 0.01) than that measured in WO silages. Aerobic stability was not influenced by inoculant treatment but low-DM silages were more (P < 0.01) resistant to spoilage. Frost-killed corn crops had a good potential to produce well fermented silage. Using LM resulted in silages with slightly higher fermentation products but it failed to improve aerobic stability of silage after 120 days of ensiling. These results indicated that inoculation of corn crops with LM for a short-duration ensilage period cannot enhance aerobic stability of silages due to insufficient acetic acid production from lactic acid conversion.

Differentiation of the Effects of pH and Lactic or Acetic Acid Concentration on the Kinetics of Listeria Monocytogenes Inactivation

1993 ◽  
Vol 56 (6) ◽  
pp. 474-478 ◽  
Author(s):  
R. L. BUCHANAN ◽  
M. H. GOLDEN ◽  
R. C. WHITING
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Acid Concentration ◽  
Brain Heart Infusion ◽  
Acetic Acid Concentration ◽  
Effects Of Ph ◽  
Lag Period ◽  
D Values ◽  
Acetic Acids

The effects of pH and lactic acid or acetic acid concentration on Listeria monocytogenes inactivation were studied in brain heart infusion broth using a three strain mixture. Combinations of lactic acid/sodium lactate and acetic acid/sodium acetate were used to achieve concentrations of 0.1, 0.5, 1.0, and 2,0 M in conjunction with pH values of 4.0, 5.0, 6.0, and 7.0. Cultures adjusted with HCl to pH 3.0 to 7.0 in 0.5 pH unit intervals were used as 0.0 M controls. Each pH/concentration combination was inoculated to a level of 108 CFU/ml and incubated at 28°C for up to 60 d. Bacterial populations were determined periodically by plate counts. Inactivation was exponential after an initial lag period. Survivor curves (log# versus time) were fitted using a linear model that incorporated a lag period. The model was subsequently used to calculate D values and “time to a 4-D (99.99%) inactivation” (t4-D); t4-D values were directly related to pH and inversely related to acid concentration. At acid/pH combinations that supported growth, the level of the organism increased slightly (2- to 10-fold) before declining. In the HCl-adjusted controls with pH's ≤5.5, the rate of inactivation was linearly related to pH. In the presence of the monocarboxylic acids, the duration of the lag period and the rate of inactivation were dependent on the pH, as well as the identity and concentration of acid. 4-D inactivation times were related to the level of undissociated lactic and acetic acids. That relationship was described by the equations, t4-D = exp (−0.1773*LA0.5 + 7.3482) and t4-D = exp (−0.1468*AA0.5 + 7.3905) for lactic and acetic acids, respectively, where LA and AA are mM of undissociated acid. These relationships were used in conjunction with the Henderson-Hasselback equation to develop a model for predicting the rate of inactivation as a function of pH and total organic acid concentration.

scholarly journals The Combined Effects of Magnesium Oxide and Inulin on Intestinal Microbiota and Cecal Short-Chain Fatty Acids

Nutrients ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 152
Author(s):  
Kanako Omori ◽  
Hiroki Miyakawa ◽  
Aya Watanabe ◽  
Yuki Nakayama ◽  
Yijin Lyu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Dietary Fiber ◽  
Magnesium Oxide ◽  
Acid Concentration ◽  
Short Chain Fatty Acids ◽  
Water Soluble ◽  
Short Chain ◽  
Acetic Acid Concentration ◽  
Chain Fatty Acids

Constipation is a common condition that occurs in many people worldwide. While magnesium oxide (MgO) is often used as the first-line drug for chronic constipation in Japan, dietary fiber intake is also recommended. Dietary fiber is fermented by microbiota to produce short-chain fatty acids (SCFAs). SCFAs are involved in regulating systemic physiological functions and circadian rhythm. We examined the effect of combining MgO and the water-soluble dietary fiber, inulin, on cecal SCFA concentration and microbiota in mice. We also examined the MgO administration timing effect on cecal SCFAs. The cecal SCFA concentrations were measured by gas chromatography, and the microbiota was determined using next-generation sequencing. Inulin intake decreased cecal pH and increased cecal SCFA concentrations while combining MgO increased the cecal pH lowered by inulin and decreased the cecal SCFA concentrations elevated by inulin. When inulin and MgO were combined, significant changes in the microbiota composition were observed compared with inulin alone. The MgO effect on the cecal acetic acid concentration was less when administered at ZT12 than at ZT0. In conclusion, this study suggests that MgO affects cecal SCFA and microbiota during inulin feeding, and the effect on acetic acid concentration is time-dependent.

scholarly journals Changes in folate characteristics and its identification in broccoli (Brassica oleracea Italica) extract fermented by Lactic Acid Bacteria Mixed Culture (LAB)

2018 ◽  
Vol 154 ◽  
pp. 04001 ◽  
Author(s):  
Yati Maryati ◽  
Agustine Susilowati
Keyword(s):  
Lactic Acid ◽  
Folic Acid ◽  
Lactic Acid Bacteria ◽  
Brassica Oleracea ◽  
Acid Concentration ◽  
Ph Value ◽  
Starter Culture ◽  
Time Interval ◽  
Fermentation Time ◽  
Total Sugars

Broccoli (Brassica oleracea Italica) was fermented by cultures of lactic acid bacteria (LAB) as a potential source of natural folic acid. This study aimed to evalte characteristic changes and to identify folate compounds from broccoli extract, fermented by mixed LAB cultures (L. bulgaricus, S. thermophulus, L.acidophilus, Bd. bifidum). The formulation of broccoli extract was fermented with variation of LAB starter culture with concentrations of 10 and 20%(v/v), and the change of characteristic of folic acid compound during fermentation (0 to 48 hours) with an interval of 8 hours was evaluated. The results showed that the fermentation of broccoli extract with different concentration of LAB culture had an effect on the concentration of folic acid produced, as well as the change of concentration of folic acid during the fermentation time interval. The optimum condition was obtained based on the highest folic acid concentration of 6.74%, at culture concentration of 20% during 24 hour fermentation with the value of folic acid concentration of 72.11 μg/mL, pH value of 4.29, total sugars of 34.61%, total acids of 0, 97%, dissolved protein of 14.64 mg/mL and total LAB of log 13.02 + 0.05 cfu / ml.

Optimization of pH and acetic acid concentration for bioconversion of hemicellulose from corncobs to xylitol by Candida tropicalis

2009 ◽  
Vol 43 (2) ◽  
pp. 203-207 ◽  
Author(s):  
Ke-Ke Cheng ◽  
Jian-An Zhang ◽  
Hong-Zhi Ling ◽  
Wen-Xiang Ping ◽  
Wei Huang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acid Concentration ◽  
Candida Tropicalis ◽  
Acetic Acid Concentration

scholarly journals THE EFFECT OF CHLORO ACETIC ACID CONCENTRATION AND TEMPERATURE REACTION OF CARBOXYMETHYL CHITOSAN FORMATION ON CATION EXCHANGE CAPACITY AND THERMAL STABILITY

2018 ◽  
Vol 10 (1) ◽  
pp. 31
Author(s):  
Candra Purnawan ◽  
Edi Pramono ◽  
Purwanto Purwanto
Keyword(s):  
Thermal Stability ◽  
Acetic Acid ◽  
Cation Exchange ◽  
Acid Concentration ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Carboxymethyl Chitosan ◽  
Temperature Reaction ◽  
Acetic Acid Concentration ◽  
Thermal Stability Of

<p>The research on the effect of chloro acetic concentration and temperature reaction of carboxymethyl chitosan formation on cation exchange capacity and thermal stability of polymer have been done. Carboxymethyl chitosan was synthesized by reaction of chitosan and chloro acetic acid with NaOH as catalyst. Polymer was characterized by Fourier Transform Infrared Spectrofotometer, cation exchange capacity test, and thermal analysis with thermogravimetric method. Carboxymethyl chitosan has strong FTIR adsorption of carboxyl group (-COO-) in 1606,70 cm<sup>-1</sup> and 1444,68 cm<sup>-1</sup>. The increasing of chloro acetic acid concentration and reaction temperature decreased cation exchage capacity and changed thermal stability of polymer.</p>

scholarly journals Processing variables of direct-write, near-field electrospinning impact size and morphology of gelatin fibers

2020 ◽  
Author(s):  
Zachary G. Davis ◽  
Aasim F. Hussain ◽  
Matthew B. Fisher
Keyword(s):  
Acetic Acid ◽  
Acid Concentration ◽  
Near Field ◽  
Fiber Formation ◽  
Direct Write ◽  
Acetic Acid Concentration ◽  
Direct Writing ◽  
Fiber Morphology ◽  
Gelatin Concentration ◽  
The Impact

AbstractSeveral biofabrication methods are being investigated to produce scaffolds that can replicate the structure of the extracellular matrix. Direct-write, near-field electrospinning of polymer solutions and melts is one such method which combines fine fiber formation with computer-guided control. Research with such systems has focused primarily on synthetic polymers. To better understand the behavior of biopolymers used for direct-writing, this project investigated changes in fiber morphology, size, and variability caused by varying gelatin and acetic acid concentration, as well as, process parameters such as needle gauge and height, stage speed, and interfiber spacing. Increasing gelatin concentration at a constant acetic acid concentration improved fiber morphology from large, planar structures to small, linear fibers with a median of 2.3 µm. Further varying the acetic acid concentration at a constant gelatin concentration did not alter fiber morphology and diameter throughout the range tested. Varying needle gauge and height further improved the median fiber diameter to below 2 µm and variability of the first and third quartiles to within +/-1 µm of the median for the optimal solution combination of gelatin and acetic acid concentrations. Additional adjustment of stage speed did not impact the fiber morphology or diameter. Repeatable interfiber spacings down to 250 µm were shown to be capable with the system. In summary, this study illustrates the optimization of processing parameters for direct-writing of gelatin to produce fibers on the scale of collagen fibers. This system is thus capable of replicating the fibrous structure of musculoskeletal tissues with biologically relevant materials which will provide a durable platform for the analysis of single cell-fiber interactions to help better understand the impact scaffold materials and dimensions have on cell behavior.

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