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Propionic acid production through anaerobic fermentation of food waste

Propionic acid production through anaerobic fermentation of food waste

Propionic acid (PA) and its salts are widely used in industries including agricultural, pharmaceutical and food industries as antifungal agents (Chen et al., 2013a; Jin & Yang, 1998). It can also be employed as precursor for the biotechnological production of value-added compounds, like e.g. acetoin (Schmidt et al., 2018) and, thus, is listed as an important platform chemical since the early 2000s (Werpy, 2004). Currently, most of the PA production around the world is done by chemical synthesis through the oxidation of petrochemicals like propane or propionaldehyde as raw material (Ahmadi et al., 2017). Acidic hydrolysis is an alternative method that gain more attention for PA production from available renewable sources, such as organic waste. It is increasingly applied with focus on biohydrogen production, a process known as dark fermentation, in which organic waste is utilized to generate renewable energy (Schmidt et al., 2018). However, the separation of single volatile fatty acids (VFA) from complex effluents such as the fermentation broth is still a challenge, due to the complex nature and the presence of various organics (Atasoy et al., 2018). Techniques such as electrodialysis (Weier et al., 1992), reactive extraction (Keshav et al., 2009a), reverse osmosis (Schlicher & Cheryan, 1990), nanofiltration (Xiong et al., 2015), and adsorption (Talebi et al., 2020) have been investigated to separate and concentrate these acids from aqueous solution and fermentation broth. This downstream processing has to be considered to make the hydrolytic process comparable to the petrochemical synthesis in terms of commercial feasibility. As a first step, it is however necessary to generally increase the portion of propionic acid in the sum of VFA usually produced in acidic hydrolysis. Accordingly, this chapter focused on the optimization of propionic production from a model and real food waste.
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Efficacy of propionic acid against the granary weevil <i>Sitophilus granarius</i> (L.)

Efficacy of propionic acid against the granary weevil <i>Sitophilus granarius</i> (L.)

DOI: 10.5073/jka.2010.425.315 Abstract Propionic acid is used to preserve feed grain, especially against fungal attack, and is known to affect stored product insects as well. In the study presented here, the effect of wheat treated with different amounts of pure propionic acid on both adult Sitophilus granarius and its progeny was investigated. Propionic acid (99.5% purity) was added to samples of 150 g of wheat at the doses of 0.5, 0.7 and 1% by weight. Subsequently, 100 adult S. granarius were released into each vial with treated wheat. Each trial was repeated three times. The untreated controls received water instead of propionic acid. Dead weevils were counted after 7 and 14 days. Insects surviving 7 days were placed back into the vials, all adults were removed after 14 days. During the period of 8 and 11 weeks after start of the experiment, the number of progeny was counted weekly. In the trials with 0.5%, 0.7% and 1% by weight, after 14 days 73.7, 37.3 and 3.7% of the adults were alive, respectively. While the mean number of progeny was 1549 in the untreated control, 1.3 and 0.3 progeny on average emerged from the grain treated with 0.5% and 0.7% propionic acid, respectively. No progeny survived in the treatment with 1% by weight. Even though complete control of adult S. granarius could not be achieved with the tested conditions, under practical situations of storage of feed grain, the described application of propionic acid will effectively suppress the mass-development of S. granarius.
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Comparative Investigations on the Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid in Plants and Cultured Cells of Tomato 

Comparative Investigations on the Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid in Plants and Cultured Cells of Tomato 

The m etabolism o f [ l - l4C ]2-(2,4-dich loroph en oxy)-propionic acid was studied in excised plants and cell suspension cultures o f tom ato. It was rapidly taken up and m etabolized by both the plants and the cultured cells. T he m etab olites, isolated by extraction with aqueous aceton e, separated and purified by TLC and H PLC , w ere identified by chem ical and spectrom etric m ethods. C on ju­ gates with carbohydrates w ere detected. G lu cose, diglucose as the main conjugating m oiety, and triglucose were found as carbohydrate com ponents within the conjugates. A lm ost the same conjugates occurred in plants and cultured cells.
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Fatty-Acid Biosynthesis and Acetyl-CoA Carboxylase as a Target of Diclofop, Fenoxaprop and other Aryloxy-phenoxy-propionic Acid Herbicides 

Fatty-Acid Biosynthesis and Acetyl-CoA Carboxylase as a Target of Diclofop, Fenoxaprop and other Aryloxy-phenoxy-propionic Acid Herbicides 

The effect of the herbicides and aryloxy-phenoxy-propionic acid derivatives diclofop, fenoxa- prop, fluazifop and haloxyfop and their ethyl, methyl or butyl esters on the de novo fatty-a[r]

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Kristall-und Molekülstruktur von 2.2-Bis(hydroxymethyI)propionsäure Crystal and Molecular Structure of 2.2-Bis(hydroxymethyl)propionic Acid 

Kristall-und Molekülstruktur von 2.2-Bis(hydroxymethyI)propionsäure Crystal and Molecular Structure of 2.2-Bis(hydroxymethyl)propionic Acid 

Oxygen Tripod Ligands, Crystal Structure According to the molecular structure of 2 . 2 -bis(hydroxymethyl)propionic acid (P3,, a = b = 6.051(1), b = 15.118(2) A, V = 479.4 Ä3, Z = 3, wR - 0.047) the corresponding carboxylate should be a good anionic oxygen tripod ligand for hard metal ions with a span of the coordinating oxygen atoms of about 2.7 Ä.

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Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid (Dichlorprop) in Barley (Hordeum vulgare) 

Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid (Dichlorprop) in Barley (Hordeum vulgare) 

G. Bärenwald et al. - Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid 487 preparative TLC in ss 1 (4-acO-2,5-dichlorprop, F. 123—125 °C, and 4-acO-2,3-dichlorprop) and meth- ylation with diazomethane (4-meO-2,5-dichlorprop- me, F. 51—53 °C). The analytic data correspond with the suggested structures. Dichlorprop-glcac 4 was synthesized from dichlorprop and acetobromoglu- cose in the presence of triethylamine according to [13]. The compound shows the following data: 'H NMR: e.g. 6 1.67 (m, 3H, -C H -C H 3); 1.9-2.1 (several s, 12H, 4 x -C O -C H 3); 3.9-5.3 (4m, 6 H at C-2 to C - 6 of glc); 4.73 (m, 1H, -C H -C H 3); 5.73 (m, 1H at C-l of glc); 6.78 (d, 1 H, aromatic proton at C-5); 7.13 (m, 1H, aromatic proton at C- 6 ); 7.36 (d, 1H, aromatic proton at C-3); MS (electron im­ pact): fragment with intact sugar-aglycon-bond: mlz
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Extracellular Production of Abscisic Acid by Soil Algae under Salt, Acid or Drought Stress 

Extracellular Production of Abscisic Acid by Soil Algae under Salt, Acid or Drought Stress 

To establish the influence of acid stress on the production of extracellular ABA, pH was adjusted 4 days before harvesting to 4.5 by addition o f 0.1 n H :S0 4 and H N 0 3 (2:1). To examine the influence o f drought stress on the production o f extracellu­ lar ABA, algae growing on BBM was cultivated in 100 Petri dishes. 50 of them were opened for 4 days in a sterile cultivator to drought. After that agar plates were extracted with bidistilled water.

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Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3) Leads to Increase of the Fatty Acid Biotransformation Activity

Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3) Leads to Increase of the Fatty Acid Biotransformation Activity

Fatty acid biotransformation activity of E. coli BL21(DE3) pCOLA-RcsB-DsrA The effect of the GDAR system engineering on the whole-cell fatty acid biotransformation activity was investigated by conducting the bioconversion of ricinoleic acid (i.e., 12-hydroxyoc- tadec-9-enoic acid (1)) into n-heptanoic acid (5) and 11-hydroxyundec-9-enoic acid (4) ( S1 Scheme ), which was described in our previous study [ 15 ]. When ricinoleic acid was added into the culture broth of the recombinant E. coli BL21(DE3) pACYC-ADH, pET-BVMO, pCOLA or E. coli BL21(DE3) pACYC-ADH, pET-BVMO, pCOLA-RcsB-DsrA expressing the alcohol dehydrogenase (ADH) of Micrococcus luteus and the Baeyer-Villiger monooxygenase (BVMO) of Pseudomonas putida, the final product formation rates of the both cells were similar to at t < 4 h ( Fig 6 ). However, the final product formation rate of E. coli BL21(DE3) pACYC-ADH, pET-BVMO, pCOLA ceased resulting in an accumulation of the reaction intermediate (2) in the culture medium at t > 4 h, when the product concentration and bioconversion yield reached over 6 mM and 45%, respectively ( Fig 6A ). This might be ascribed to the toxicity of n- heptanoic acid ( Fig 5B ). In contrast, the final product formation rate of E. coli BL21(DE3) pACYC-ADH, pET-BVMO, pCOLA-RcsB-DsrA was further maintained resulting in a final product concentration of over 10 mM (conversion yield, 68%), which was 1.6-fold higher as compared to the E. coli BL21(DE3) pACYC-ADH, pET-BVMO, pCOLA. This value was also Fig 4. The relationship between GadA/B activity and cultivation pH (A) or n-heptanoic acid concentration (B). The GadA/B
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Docosahexaenoic acid suppresses arachidonic acid-induced proliferation of LS
174T human colon carcinoma cells

Docosahexaenoic acid suppresses arachidonic acid-induced proliferation of LS 174T human colon carcinoma cells

In this context it has been proposed that the human genetic profile was originally established on a n-6 to n-3 PUFA ratio of approximately 1:1 as found in “ancient” diets, whereas today’s Western diet has been estimated to provide n-6 to n-3 PUFAs in a ratio of 15:1–20:1. It has been hypothesized that this may contribute to many serious health issues typically found in Western societies, including CRC. However, previous in vitro observations have led to some uncertainty regarding differential roles of n-3 and n-6 PUFAs in CRC cells. While the majority of investigations conducted in this field addressed neither the effects of n-6 PUFAs nor the impact of a balanced n-6 to n-3 PUFA ratio, several other studies reported n-3 and n-6 PUFAs to exert anti-cancerous effects in vitro. Hence, it was the aim of the present study to investigate the impact of n-3 PUFA docosahexaenoic acid (DHA) and n-6 PUFA AA and their combination on CRC cell line LS 174T in vitro.
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Aspartic Acid-Aspartate and Glutamic Acid-Glutamate Hydrogen Bonds Having Great Proton Polarizability — IR Investigations 

Aspartic Acid-Aspartate and Glutamic Acid-Glutamate Hydrogen Bonds Having Great Proton Polarizability — IR Investigations 

a-Amino and a-carboxylate group protected aspartate (Z-asp-OMe) and glutamate (Z-glu- OBZ1) solutions in CH 2 C1 2 are studied as function o f the addition o f the respective salts by IR spectroscopy. The antisymmetrical stretching vibration o f the - C O j groups shifts to the position where v C = 0 of the acid groups is observed, indicating that both anions in the acid-anion complexes are strongly influenced by the proton. With the formation o f these complexes a continuum arises preferentially in the region 1600-900 cm -1 demonstrating that the OH • • • 0 ~ ^ “O • • HO bonds formed show great proton polarizability. These hydrogen bonds are short and the proton potential is probably a broad flat well. The degree o f the formation o f these hydrogen bonds is determined. Finally, it is discussed that positive charge can easily be translocated via such hydrogen bonds in protein molecules.
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Studies of the Reaction of Various 1,2-Disubstituted Benzenes with Crotonic Acid in Polyphosphoric Acid 

Studies of the Reaction of Various 1,2-Disubstituted Benzenes with Crotonic Acid in Polyphosphoric Acid 

This work has been digitalized and published in 2013 by Verlag Zeitschrift für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative[r]

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Synthesis of 5-AminoIevulinic Acid 

Synthesis of 5-AminoIevulinic Acid 

T herefore, it is often used for biochem ical investiga­ tions and a sim ple synthesis would be useful. Till now , a number o f synthesis have been described, which are m ostly tim e-consum ing or result in difficult to clean product(s) (for a com plete list see [1 — 3]). Som e years ago, M cD onald [4] published the bromi- nation o f levulinic acid yielding 3-bromo- and 5-brom olevulinic acid which can be separated by dis­ tillation. We obtained 5-am inolevulinic acid from 5-brom olevulinic acid by a 2-step sequence (Gabriel- synthesis and hydrolysis) in 33% overall yield (Fig. 2).
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Chemistry of Fenchonesulfonic Acid Derivatives 

Chemistry of Fenchonesulfonic Acid Derivatives 

{ ( 1 R) -3,3-Dimethyl-2-oxobicyclo[2.2.1 ]hept-l -yl}- methanesulfonyl chloride (3) and { ( 1 S, Z)-l-chloro- 7,7-dimethylbicyclo [2.2.1 ]hept-2-y lidenejmethane- sulfonyl chloride (10): To fenchonesulfonic acid (25 g, 0.1 mol of the m onohydrate), thionyl chlo­ ride (100 ml) was added, and the mixture kept at 50 °C for 12 h. The excess of thionyl chloride was removed in vacuum. Recrystallization from hex­ ane gave fenchone sulfonyl chloride (3), having properties identical to those described [12], yield 7 0-9 0 % . The m other liquors contained a mixture of 3 and 10 which could not be separated, but NM R data for 10 could be obtained from the mix­ ture (Tables I and II).
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Synthese des Indolalkaloids α-Cyclopiazonic Acid

Synthese des Indolalkaloids α-Cyclopiazonic Acid

Benzoesäureanhydrid (471 mg, 2.08 mmol) gelöst in DMF (1.6 ml) wird tropfenweise bei 0 °C unter Stickstoffatmosphäre über eine Glasspritze zugegeben und die Reaktion anschließend noch [r]

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Acid sulfate soils: Processes and assessment

Acid sulfate soils: Processes and assessment

(2) Elevated backgrounds in the analysis of sulfates and organic sulfur compounds Elemental sulfur is a relevant intermediate compound of sulfide oxidation, contributing to the APP in acid sulfate soil landscapes. Therefore, a reliable quantification is required for assessment. The reported recoveries of elemental sulfur in conventional CRS-procedures range widely. None achieves a complete recovery of elemental sulfur. CRS-procedures involving the use of additional solvents (e.g. dimethylformamide, DMF) achieve a better recovery although still not always a complete recovery. Further drawbacks of these methods are the high standard deviation and long reactions times for the analysis of elemental sulfur. The method presented in this thesis is the first CRS-method ever reported, achieving a complete recovery of elemental sulfur irrespective of its form. Furthermore, the introduction of a filtration step during the common processing steps significantly decreased the recoveries of sulfates and organic sulfur compounds. Thus, the selectivity of the method was significantly improved. These achievements are not only beneficial to acid sulfate soil studies but also to research in systems with high elemental sulfur content or low amounts of CRS in the presence of sulfates or organic sulfur compounds.
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Therapeutic drug monitoring of mycophenolic acid

Therapeutic drug monitoring of mycophenolic acid

high MPAG exposure in plasma. The function of MRAP-2 is not only the excretion of MPAG into the bile but also other endogenous (e.g. Bilirubin) and exogenous (e.g. diclofenac and valproic acid) conjugates. CsA is clinically relevant because it can reduce the MPA exposure upto 30-40% and it is nephrotoxic [27, 60]. In a 2-year, randomized study, L Frimat et al showed an improvement in the kidney function without increasing the risk for graft rejections on 50% CsA dose reduction in combination with MMF [24]. There also exists a recommendation to measure MPA plasma levels dependent on co-mediaction, such as CyA or Tacrolimus. According to Shaw LM et al and if MPA is prescribed together with CyA, the trough MPA levels should range between 1.0-3.5 μg/mL. The AUC target is between 30-60 μg*h/mL [67] after renal or heart transplantation. And if prescribed together with Tacrolimus then trough levels differ a lit bit (> 1.9 ug/mL) [71].
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Itaconic acid production by ustilago maydis

Itaconic acid production by ustilago maydis

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Retinoic acid signaling after nerve injury

Retinoic acid signaling after nerve injury

trypsinated. The serum protease trypsin disrupts peptide chains of amino acid residues of L- arginine and L-lysine. Cells were incubated for about 2 min with 1.5 ml of a 0.25% trypsine/EDTA-solution at 37°C and cell disruption was controlled under a microscope. Again, serum terminated the enzymatic reaction. The cell suspension was transferred into 8 ml FCS containing medium and centrifuged. Pellet was resuspended in 1 ml of fibroblast- binding monoclonal anti-mouse Thy 1.1 antibody (Sigma M7898), diluted 1/40 in PBS, and 1 ml DMEM and incubated at 37°C for 30 min. Lyophilized baby rabbit complement (Linaris CL 3441), dissolved in 1 ml sterile water was added for another 30 min. Complement proteins bind to Thy 1.1 antibody labeled fibroblasts and induce the formation of pores in the cell membrane and by this lysis of the tagged cells. Lysis was blocked by adding serum containing medium. Pure Schwann cells were centrifuged, resuspended in 5 ml DMEM containing 10% FCS, 2 µM forskolin (ICN Biomedicals) and 100 µg/ml bovine pituitary extract (Invitrogen) and cultured in poly-L-lysine (Sigma) coated (200µg/ml in sterile water) T25-culture dishes. Confluent Schwann cells were expanded on poly-L-lysine coated T75-culture dishes with DMEM containing 10% FCS and 2 µM forskolin. Forskolin activates the adenylyl cyclase, thus raises the level of cyclic adenosine mono-phosphate (cAMP). During experiments cells were kept in medium without forskolin 24 hrs before RA treatment. Confirmation of Schwann cell identity was given by immunohistochemical staining with the S-100 antibody (Sigma).
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Interaction of Ascorbic Acid with Disulfides 

Interaction of Ascorbic Acid with Disulfides 

Recent studies h av e show n th e a p p e aran c e o f a characteristic electron spin resonance (EP R ) signal when ascorbic acid (A H 2) reacts w ith a variety o f biological m olecules [1], T his signal has been as­ signed to the a sco rb ate radical ( A H ) form ed by binding electrostatically to co m p o u n d s containing both, disulfides a n d am ines. T w o q uestions have been left unansw ered by these studies, nam ely the role o f sulfur in th is rea ctio n and th e a b ility o f A H 2

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Composite nanocarriers for nucleic acid delivery

Composite nanocarriers for nucleic acid delivery

hand, delivery of nucleic acids using delivery vehicles such as liposomes, polymers and nanoparticles has been met with considerable success [18-20]. 1,2-dioleoyl-3- trimethylammonium-propane (DOTAP), 1,2-di-O-octadecenyl-3-trimethylammonium propane (DOTMA), (1-[2-(9-(Z)-octadecenoyloxy)ethyl] -2-(8-(Z)-heptadecenyl) -3 (hydroxyethyl) imidazolinium chloride (DOTIM), N-methyl-4(dioleyl)methylpyridiniumchloride (SAINT), 1,2-dimyristyloxy-propyl-3-dimethyl-hydroxy ethyl ammonium bromide (DMRIE), 1,2-di- (9Z-octadecenoyl)-sn-glycero-3- [(N- (5-amino-1-carboxypentyl) iminodiacetic acid) succinyl (DOGS), and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) are the most frequently used lipids for delivery of nucleic acids [21, 22]. Among polymers, polyethylenimine (PEI; linear and branched) of various molecular weights, poly-L-lysine (PLL), chitosan, polyamidoamine (PAMAM) are widely used [23, 24]. Poly (lactic-co-glycolic acid) (PLGA) and silica particles have been proven to be indispensable for formulation of nanoparticles for gene delivery [20]. Several therapies which are under clinical evaluation are based upon one of these vectors [25].
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