PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: VIII. pH CONTROL IN AEROBACILLUS POLYMYXA FERMENTATIONS AND ITS EFFECTS ON PRODUCTS AND THEIR RECOVERY

1946 ◽  
Vol 24f (1) ◽  
pp. 12-28 ◽  
Author(s):  
G. A. Adams ◽  
J. D. Leslie
Keyword(s):  
Carbon Dioxide ◽  
Heat Treatment ◽  
Calcium Carbonate ◽  
Nicotinic Acid ◽  
Acid Production ◽  
Ammonium Hydroxide ◽  
Ph Control ◽  
Ash Content ◽  
Carbon Balances ◽  
Ph Range

Comparative studies have shown that the pH of 15% wheat mashes fermented by Aerobacillus polymyxa can be as satisfactorily controlled by ammonium hydroxide as by calcium carbonate. The formation of 2,3-butanediol and ethanol was unaffected by all pH levels tested (5.8, 6.0, 6.5, 7.0) with the possible exception of pH 7.0, where a slight diminution of diol formation appeared at 96 hr. Over the pH range 5.8 to 6.0, the amount of ammonium hydroxide required, the escape of ammonia from the mash, and the production of acid were all minimized. The consumption of ammonia was greatest in the first 36 hr. of the fermentation owing to rapid acid production. Fermentation at the different pH levels did not affect the butanediol–ethanol ratio, which was approximately 1.5.Replacement of calcium carbonate by ammonium hydroxide reduced the ash content of the unfermented residue from approximately 20 to 4%. Protein contents (N × 5.7) of insoluble residues from carbonate and ammonia treated washes were 25 and 32%, respectively. In both mashes approximately 50% of the unfermented solids were soluble.Calculation of carbon balances on fermentables showed that increased acid production was accompanied by a decrease in carbon dioxide formation.Riboflavin and nicotinic acid contents per 100 gm. of fermented mash averaged 19.2 and 1270 μgm., respectively and were unaffected by pH of fermenting mash and heat treatment at 100 °C. for 10 hr. The riboflavin showed an 80% increase over that present in the original wheat; nicotinic acid showed a 40% decrease.

PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: XXXIII. AUTOMATIC pH CONTROL IN THE DISSIMILATION OF SUCROSE BY BACILLUS POLYMYXA

1949 ◽  
Vol 27f (12) ◽  
pp. 457-469
Author(s):  
R. W. Watson ◽  
Florence Tamboline ◽  
G. W. Harmsen
Keyword(s):  
Carbon Dioxide ◽  
Organic Acids ◽  
Sucrose Concentration ◽  
Marked Change ◽  
Ammonium Hydroxide ◽  
Carbon Dioxide Production ◽  
Ph Control ◽  
Invert Sugar ◽  
Aerobic Conditions ◽  
Chemical Balance

An electronic control circuit was used to maintain pH within ±0.02 units between successive additions of soluble alkali. Carbon balances show the effects of a series of pH levels and of a range of sucrose concentrations on the proportional yields of end products. There is a marked change in the chemical balance of this fermentation at about pH 7.0, correlated with a suppression of the acetoin enzyme system. Above pH 6.8 a sharp increase in acid production is correlated with decreased formation of diol and carbon dioxide: below pH 6.8 the yield of organic acids decreases steadily. Most efficient conversion to diol occurs from pH 6.0 to 6.4. Several reasons are advanced for selecting pH 6.2 as the optimum. Under anaerobic conditions the fermentation rate is increased over that under aerobic conditions. Diol yields increase and ethanol yields decrease steadily with increasing sucrose concentrations. The increases in diol are accompanied by decreasing yields of organic acids, and not by changes in carbon dioxide production, which remains relatively uniform. The sucrose concentration most efficient for conversion to diol is about 8%, which is dissimilated anaerobically in 30 hr. at pH 6.2 to yield 65 mM. (millimoles) of diol per 100 mM. of invert sugar fermented. Under aerobic conditions the diol–ethanol ratios show a marked increase, and reach a maximum of about 11 at 10% sucrose. This is due largely to increased acetoin and decreased ethanol formation. The dissimilation of 6% sucrose reaches 98% in 71 hr. under aerobic conditions and yields 82 mM. of diol plus acetoin per 100 mM. of invert sugar fermented. The use of either sodium or potassium hydroxide in place of ammonium hydroxide increases five times the period for complete dissimilation of 5% sucrose. Advantages of controlling the reaction by addition of ammonium hydroxide are reviewed.

Butyric Acid Fermentation from Rice Straw with Undefined Mixed Culture: Enhancement by pH Control

2013 ◽  
Vol 807-809 ◽  
pp. 1198-1202
Author(s):  
Bin Ling Ai ◽  
Jian Zheng Li ◽  
Xue Chi ◽  
Jia Meng
Keyword(s):  
Mixed Culture ◽  
Rice Straw ◽  
Butyric Acid ◽  
Acid Production ◽  
Ph Control ◽  
Cellulolytic Enzyme ◽  
Acid Fermentation ◽  
Feeding Method ◽  
Butyric Acid Production ◽  
Ph Range

This study aimed to find out the optimum pH range and a buffer feeding method for butyric acid production from rice straw by undefined mixed culture. A serial experiment was conducted at various pH levels from 5.0 to 7.0. The results showed that neutral pH improved rice straw conversion and hence carboxylic acid production. The highest butyric acid production was achieved at pH range of 6.0 to 6.5. Another serial experiment was performed at pH 6.0 to 6.5 buffered with CaCO3, NaHCO3, NH4HCO3 and their combinations, respectively. The results indicated that different buffers had different effects on product spectrum, and that CaCO3 combined with NaHCO3 was an effective buffer for butyric acid production. This study presents an alternative way for butyric acid production from lignocellulosic biomass without supplementary cellulolytic enzyme.

Fluoride sorption by soil components: calcium carbonate, humic acid, manganese dioxide and ailica

Soil Research ◽  
1985 ◽  
Vol 23 (3) ◽  
pp. 429 ◽  
Author(s):  
H Farrah ◽  
J Slavek ◽  
WF Pickering
Keyword(s):  
Calcium Carbonate ◽  
Humic Acid ◽  
Ash Content ◽  
Fluoride Ions ◽  
Ph Values ◽  
Counter Ions ◽  
Soil Components ◽  
Significant Uptake ◽  
Ph Range ◽  
Calcium Compounds

The ability of individual soil components to adsorb fluoride ions from dilute solutions (1-12 mg L-1 F-), at different pH values, has been investigated. No significant uptake was detected using substrates such as calcite, hydrous manganese(1v) oxide, cryptomelane, �-MnO2, pyrolusite, silica or silica gel, over the pH range 3-8 (for calcite, 6-9). The sorption of F- by calcite and humic acids at higher solution levels (up to 200 mg L-1) was also examined. Uptake by CaCO3 was observed when [F-] was >7 x 10-4 mol L-1, with the moles retained (pH -8.5) being approximately 1.6[F-]2. The amount of F removed increased on lowering the pH or on adding Ca2+, and it is proposed that the overall reaction is described by the equation CaCO3(S) + 2F- <=>CaF2(S) + CO23-. Two humic acid samples adsorbed increasing amounts of F- as the pH was lowered below 6.5, and increasing amounts of A1 and fluorocomplexes were detected in solution. The amount sorbed (mol kg-', at pH 5.5-6) varied with ash content and equalled either 16[F-]0.64 or 60[F-1. The major interaction appears to be HF attack on aluminosilicates in the ash fraction, with lesser contributions from sorption on calcium compounds and interaction with the counter-ions associated with the humic acid functional groups (e.g. Ca2+, Al3+, Fe3+).

scholarly journals Stabilization and Release of Palm Tocotrienol Emulsion Fabricated Using pH-Sensitive Calcium Carbonate

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 358
Author(s):  
Phui Yee Tan ◽  
Beng Ti Tey ◽  
Eng Seng Chan ◽  
Oi Ming Lai ◽  
Hon Weng Chang ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Droplet Size ◽  
Entrapment Efficiency ◽  
Ph Sensitive ◽  
Emulsion System ◽  
Ph Responsive ◽  
Small Droplet ◽  
Homogenization Time ◽  
Oil In Water ◽  
Ph Range

Calcium carbonate (CaCO3) has been utilized as a pH-responsive component in various products. In this present work, palm tocotrienols-rich fraction (TRF) was successfully entrapped in a self-assembled oil-in-water (O/W) emulsion system by using CaCO3 as the stabilizer. The emulsion droplet size, viscosity and tocotrienols entrapment efficiency (EE) were strongly affected by varying the processing (homogenization speed and time) and formulation (CaCO3 and TRF concentrations) parameters. Our findings indicated that the combination of 5000 rpm homogenization speed, 15 min homogenization time, 0.75% CaCO3 concentration and 2% TRF concentration resulted in a high EE of tocotrienols (92.59–99.16%) and small droplet size (18.83 ± 1.36 µm). The resulting emulsion system readily released the entrapped tocotrienols across the pH range tested (pH 1–9); with relatively the highest release observed at pH 3. The current study presents a potential pH-sensitive emulsion system for the entrapment and delivery of palm tocotrienols.

scholarly journals Genes encoding putative bicarbonate transporters as a missing molecular link between molt and mineralization in crustaceans

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shai Abehsera ◽  
Shmuel Bentov ◽  
Xuguang Li ◽  
Simy Weil ◽  
Rivka Manor ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Molecular Mechanisms ◽  
Ph Control ◽  
Functional Genomic ◽  
Single Event ◽  
Tight Coupling ◽  
Molt Cycle ◽  
Mineral Deposition ◽  
Bicarbonate Transporters ◽  
Genes Encoding

AbstractDuring their life, crustaceans undergo several molts, which if theoretically compared to the human body would be equivalent to replacing all bones at a single event. Such a dramatic repetitive event is coupled to unique molecular mechanisms of mineralization so far mostly unknown. Unlike human bone mineralized with calcium phosphate, the crustacean exoskeleton is mineralized mainly by calcium carbonate. Crustacean growth thus necessitates well-timed mobilization of bicarbonate to specific extracellular sites of biomineralization at distinct molt cycle stages. Here, by looking at the crayfish Cherax quadricarinatus at different molting stages, we suggest that the mechanisms of bicarbonate ion transport for mineralization in crustaceans involve the SLC4 family of transporters and that these proteins play a key role in the tight coupling between molt cycle events and mineral deposition. This discovery of putative bicarbonate transporters in a pancrustacean with functional genomic evidence from genes encoding the SLC4 family—mostly known for their role in pH control—is discussed in the context of the evolution of calcium carbonate biomineralization.

Controlled preparation of micro–nano hierarchical hollow calcium carbonate microspheres by pressurized-CO2 carbonization and their CaCO3:Eu3+ photoluminescence properties

CrystEngComm ◽  
2021 ◽  
Vol 23 (16) ◽  
pp. 3033-3042
Author(s):  
Liubin Shi ◽  
Mingde Tang ◽  
Yaseen Muhammad ◽  
Yong Tang ◽  
Lulu He ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Calcium Carbonate ◽  
Calcium Hydroxide ◽  
Hierarchical Structure ◽  
Ethylenediaminetetraacetic Acid ◽  
Disodium Salt ◽  
Hollow Microspheres ◽  
Photoluminescence Properties ◽  
Controlled Preparation

Herein, calcium carbonate hollow microspheres with a micro–nano hierarchical structure were successfully synthesized using disodium salt of ethylenediaminetetraacetic acid (EDTA-2Na) as an additive, by bubbling pressurized carbon dioxide and calcium hydroxide at 120 °C.

Amine-Citrate Buffers for pH Control in Starch Gel Electrophoresis

1972 ◽  
Vol 29 (8) ◽  
pp. 1169-1172 ◽  
Author(s):  
J. W. Clayton ◽  
D. N. Tretiak
Keyword(s):  
Gel Electrophoresis ◽  
Ph Control ◽  
Starch Gel Electrophoresis ◽  
Good Resolution ◽  
Citrate Buffer ◽  
Starch Gel ◽  
Ph Range ◽  
Amine Buffers

Amine-citrate buffer systems for pH control in starch gel electrophoresis gave good resolution of some dehydrogenase isozymes. The pK's of three new amine buffers, N-(3-aminopropyl)-morpholine, pK2 25 C, 6.12; N-(3-aminopropyl)-diethanolamine, pK2 25 C, 6.90; and 1,3-bis(dimethylamino)-2-propanol, pK2 25 C, 7.55, were determined at 5 C intervals in the range 10–40 C. These compounds, together with N, N-bis(2-hydroxyethyl)iminotris(hydroxymethyl)methane (bis-Tris) and tris-(hydroxymethyl)-methylamine(Tris), provide a series of amine buffers with pK's at 0.5 unit intervals in the pH range 6.1–8.1.

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