scholarly journals Structural and physiological properties of natural petroleum acids from middle oil fractions of "Kelebija" oil

2004 ◽  
pp. 87-94 ◽  
Author(s):  
Vera Cirin-Novta ◽  
Ksenija Kuhajda ◽  
Slavko Kevresan ◽  
Julijan Kandrac ◽  
Ljubica Grbovic ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Acid Concentration ◽  
Physiological Activity ◽  
Field Ionization ◽  
High Biological Activity ◽  
Physiological Properties ◽  
Oil Fractions ◽  
High Auxin ◽  
Very High ◽  
Petroleum Acid

The investigated petroleum acids have been isolated from middle oil fractions (b.p. 270-380?C) of Vojvodina crude oil "Kelebija." Group-structural analysis was performed with low resolution mass spectrometry using Field Ionization and Chemical Ionization. The identified carboxylic acids, CnH2n+zO2, belong to the series of monocyclic, bicyclic, tricyclic and tetracyclic carboxylic acids. Physiological activity of isolated petroleum acids was determined using aqueous solutions of potassium salts. High auxin activity was determined using the coleoptile test (20.5% increase in coleoptile) with petroleum acid concentration of 10-7M, and very high biological activity of gibberellin type was determined using the endosperm test (31.6% increase in concentration of reducing sugars) with petroleum acid concentration of 10-7M.

scholarly journals Specialized mechanoreceptor systems in rodent glabrous skin

2018 ◽  
Author(s):  
Jan Walcher ◽  
Julia Ojeda-Alonso ◽  
Julia Haseleu ◽  
Maria K. Oosthuizen ◽  
Ashlee H. Rowe ◽  
...  
Keyword(s):  
Small Group ◽  
Rodent Species ◽  
Glabrous Skin ◽  
Skin Area ◽  
Mechanical Stimuli ◽  
Orientation Sensitivity ◽  
Hairy Skin ◽  
Physiological Properties ◽  
Sensory Fibers ◽  
Very High

AbstractRodents use their forepaws to actively interact with their tactile environment. Studies on the physiology and anatomy of glabrous skin that makes up the majority of the forepaw are almost non-existent in the mouse. Here we developed a preparation to record from single sensory fibers of the forepaw and compared anatomical and physiological receptor properties to those of the hind paw glabrous and hairy skin. We found that the mouse forepaw skin is equipped with a very high density of mechanoreceptors; >3 fold more than hind paw glabrous skin. In addition, rapidly adapting mechanoreceptors that innervate Meissner’s corpuscles of the forepaw were several-fold more sensitive to slowly moving mechanical stimuli compared to their counterparts in the hind paw glabrous skin. All other mechanoreceptors types as well as myelinated nociceptors had physiological properties that were invariant regardless of which skin area they occupied. We discovered a novel D-hair receptor innervating a small group of hairs in the middle of the hind paw glabrous skin in mice. Glabrous D-hair receptors were direction sensitive albeit with an orientation sensitivity opposite to that described for hairy skin D-hair receptors. Glabrous D-hair receptors do not occur in all rodents, but are present in North American and African rodent species that diverged more than 65 million years ago. The function of these specialized hairs is unknown, but they are nevertheless evolutionarily very ancient. Our study reveals novel physiological specializations of mechanoreceptors in the glabrous skin that likely evolved to facilitate tactile exploration.

scholarly journals Biosorption of lanthanum and samarium by chemically modified free Bacillus subtilis cells

2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Ellen C. Giese ◽  
Caio S. Jordão
Keyword(s):  
Bacillus Subtilis ◽  
Waste Treatment ◽  
Physiological Activity ◽  
Lanthanide Ions ◽  
Aquatic Environments ◽  
Light Rare Earth ◽  
Chemically Modified ◽  
Langmuir Isotherm Model ◽  
Light Rare Earth Elements ◽  
Very High

Abstract Previous studies showed that Bacillus subtilis possessed high physiological activity in industrial waste treatment as a biosorbent for recovery metals, and in this study, the sorption capacity for both La3+ and Sm3+ was demonstrated. The effects of lanthanide concentration and contact time were tested to acid and alkali pre-treated cells. Very high levels of removal, reaching up to 99% were obtained for both lanthanide ions. Langmuir isotherm model was applied to describe the adsorption isotherm and indicated a better correlation with experimental data R2 = 0.84 for La3+ using sodium hydroxide pre-treated free cells and R2 = 0.73 for Sm3+ to acid pre-treated B. subtilis cells as biosorbents. Results of this study indicated that chemically modified B. subtilis cells are a very good candidate for the removal of light rare-earth elements from aquatic environments. The process is feasible, reliable, and eco-friendly.

Nobiletin: a citrus flavonoid displaying potent physiological activity

2016 ◽  
Vol 72 (2) ◽  
pp. 124-127 ◽  
Author(s):  
Shuji Noguchi ◽  
Haruka Atsumi ◽  
Yasunori Iwao ◽  
Toshiyuki Kan ◽  
Shigeru Itai
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Physiological Activity ◽  
Covalent Bond ◽  
Physiological Properties ◽  
Wide Range ◽  
Methoxy Groups ◽  
Citrus Peels ◽  
Anti Inflammatory ◽  
Chromene Ring

Nobiletin [systematic name: 2-(3,4-dimethoxyphenyl)-5,6,7,8-tetramethoxy-4H-chromen-4-one; C21H22O8] is a flavonoid found in citrus peels, and has been reported to show a wide range of physiological properties, including anti-inflammatory, anticancer and antidementia activities. We have solved the crystal structure of nobiletin, which revealed that the chromene and arene rings of its flavone moiety, as well as the two methoxy groups bound to its arene ring, were coplanar. In contrast, the C atoms of the four methoxy groups bound to the chromene ring are out of the plane, making the molecule conformationally chiral. A comparison of the crystal structures of nobiletin revealed that it could adopt a variety of different conformations through rotation of the covalent bond between the chromene and arene rings, and the orientations of methoxy groups bound to the chromene ring.

On the evolution of plant secondary chemical diversity

1991 ◽  
Vol 333 (1267) ◽  
pp. 273-280 ◽  
Keyword(s):  
Biological Activity ◽  
Plant Defence ◽  
Secondary Compounds ◽  
Chemical Diversity ◽  
High Biological Activity ◽  
Active Compounds ◽  
Low Probability ◽  
Secondary Chemical ◽  
Very High ◽  
High Diversity

A common-sense evolutionary scenario predicts that well-defended plants should have a moderate diversity of secondary compounds with high biological activity. We contend that plants actually contain a very high diversity of mostly inactive secondary compounds. These patterns result because compounds arising via mutation have an inherently low probability of possessing any biological activity. Only those plants that make a lot of compounds will be well defended because only high diversity confers a reasonable probability of producing active compounds. Inactive compounds are retained, not eliminated, because they increase the probability of producing new active compounds. Plants should therefore have predictable metabolic traits maximizing secondary chemical diversity while minimizing cost. Our hypothesis has important implications to the study of the evolution of plant defence.

scholarly journals Optimization of Critical Parameters for Carbodiimide Mediated Production of Highly Modified Chitosan

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2702
Author(s):  
Henrik-Alexander Christ ◽  
Yannick Bourgat ◽  
Henning Menzel
Keyword(s):  
Carboxylic Acids ◽  
Propionic Acid ◽  
Methacrylic Acid ◽  
Critical Parameters ◽  
Optimal Parameters ◽  
Efficient Synthesis ◽  
Tight Control ◽  
Modified Chitosan ◽  
Broad Applicability ◽  
Very High

An optimization of the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and hydroxy benzotriazole mediated conjugation of the polysaccharide chitosan with functional carboxylic acids was shown. Optimal parameters that enable resource-efficient synthesis of highly functionalized chitosan were identified. In particular, use of only catalytic instead of stoichiometric amounts of hydroxy benzotriazole and tight control of pH in reaction mixture resulted in highly efficient incorporation of the desired moieties as side chains in chitosan. As a result, the model reactant 4-azidobenzoic acid was incorporated resulting in a degree of substitution of over 30% with very high coupling efficacy of up to 90%. Similar results were obtained with other carboxylic acids such as methacrylic acid, 3-(2-furyl) propionic acid and 3-maleimido propionic acid, highlighting the broad applicability of our findings for the functionalization of chitosan.

SYNTHETIC ACETYLENE CARBOXYLIC ACIDS

2020 ◽  
Vol 36 (2) ◽  
pp. 10-17
Author(s):  
U.A. Abidov ◽  
◽  
S.G. Usmanova ◽  
Kh.M. Zhamolova ◽  
U.O. Mamatkulova ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Physiological Activity ◽  
Biological Properties ◽  
Grignard Reaction ◽  
Chemical Transformations ◽  
Acid Chlorides ◽  
Acetylenic Acids ◽  
Aromatic Heterocyclic

The article presents some methods for the synthesis of acetylene mono, dicarbonoaliphatic, aromatic, heterocyclic acids. Among them, some possess antifungal and biological properties. By the interaction of acids or acid chlorides with the corresponding alcohols, esters can be obtained. Their biological properties, as well as some chemical transformations, were studied. Many synthetic acetylenic acids and their derivatives were synthesized mainly by the Grignard reaction and other methods in order to study their physiological activity. Some of them have gained application as a stabilizer of corrosion methods and others.

Study of an organoclay for the sorption of dissolved organic compounds in the wastewaters from offshore platform operation

2009 ◽  
Vol 59 (8) ◽  
pp. 1495-1503 ◽  
Author(s):  
C. Scurtu ◽  
T. Leiknes ◽  
H. Helness
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acids ◽  
Acid Concentration ◽  
Research Work ◽  
Sorption Process ◽  
Offshore Platform ◽  
Acetic Acid Concentration ◽  
Organically Modified ◽  
Benzene Toluene ◽  
Dissolved Organic Compounds

The goal of this research work was to find a sorbent able to selectively retain the harmful dissolved compounds in the wastewaters from offshore platform operation but not the carboxylic acids and to study the effects of the most important parameters on the sorption process. BTX compounds (benzene, toluene and p-xylene) and acetic acid were chosen as the representatives of the harmful compounds and carboxylic acids groups respectively since they are found in the highest concentrations. An organically modified clay was determined to be the most suitable sorbent, where performance was evaluated at different values of pH (3, 5 and 8), acetic acid concentration (0, 160 and 320 mg/l), salinity (0, 35 and 70 g/l) and temperature (20, 40 and 60°C). Results show that there is a sorption competition between BTX and acetic acid. Sorption of BTX compounds decreased with increasing initial acetic acid concentration and temperature, and increased proportionally with the salinity. Sorption of acetic acid, however, decreased with increasing pH, temperature and salinity.

Fractional Stark State Selective Electric Field Ionization of Very High-nRydberg States of Molecules

1996 ◽  
Vol 76 (19) ◽  
pp. 3530-3533 ◽  
Author(s):  
Hans-Jörg Dietrich ◽  
Klaus Müller-Dethlefs ◽  
Leonid Ya. Baranov
Keyword(s):  
Electric Field ◽  
Field Ionization ◽  
Very High

scholarly journals The œstrogenic activity of some condensed-ring compounds in relation to their other biological activities

1934 ◽  
Vol 114 (788) ◽  
pp. 272-286 ◽  
Keyword(s):  
Biological Activities ◽  
Physiological Activity ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Analogous Structure ◽  
Ring Compounds ◽  
Condensed Carbon ◽  
Preliminary Account ◽  
Biological Relationship ◽  
Very High

The very rapid progress which has been made recently in the chemistry of the œstrogenic hormones, of which an excellent has been given by Girard (1933) has established that these substances are hydrogenated phenanthrene derivatives containing oxygen in the molecule ( cf . Butenandt, Weidlich, and Thompson, 1933). On the assumption of a biological relationship between these hormones and the sterols and bile acids, an assumption which seems justifiable, although it cannot yet be regarded as rigidly proved, œstrone (= ketohydroxyœstratriene) is probably represented by formula I or II. The present communication describes the examination for œstrogenic properties of a number of condensed carbon-ring compounds of somewhat analogous structure in an attempt to elucidate the molecular conditions necessary for œstrogenic activity. A preliminary account of some of these experiments has already been given (cook, Dodds, and Hewett, 1933; cook and Dodds, 1933). Our investigations have brought to light a number of pure synthetic compounds, of known molecular structure, which show this physiological activity, and in some of the compounds studied the activity is of a very high order. It will be observed that one of two oxygen atoms in œstrone is ketonic and the other hydroxylic. Girard (1933) has suggested that these two types of oxygen-containing groups are biologically equivalent, and our own experiments group but no hydroxyl group, whereas others contain only hydroxyl groups in a similar type of molecule.

scholarly journals NONSENSE MUTATIONS IN THE ADE3 LOCUS OF SACCHAROMYCES CEREVISIAE

Genetics ◽  
1972 ◽  
Vol 71 (2) ◽  
pp. 217-232
Author(s):  
Elizabeth W Jones
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Nonsense Mutations ◽  
Physiological Properties ◽  
Interesting Possibility ◽  
Very High

ABSTRACT Fifty seven mutations at the ade3 locus have been crossed to ochre, amber and ochre-amber suppressors. 70% (39/56) of the mutations at this locus are nonsense mutations; 61% (34/56) are ochre mutations and 9% (5/56) are amber mutations. The frequency of nonsense mutations among ade3 alleles recovered is very high and raises the interesting possibility that only polar mutations at this locus are recovered. An hypothesis to explain these genetical findings as well as physiological properties of these mutations is proposed.

Sign in / Sign up

Export Citation Format

Share Document