ANTIPODAL SPECIFICITY IN THE INHIBITION OF GROWTH OF LACTOBACILLUS ARABINOSUS BY AMINO ACIDS

The possibility that contact inhibition of growth in cultures of human diploid cells is influenced by the effects of cell crowding on nutrient uptake by the cells was investigated. Two human lung cell lines were compared, the diploid line MRC-5 and the heteroploid line L-132. In pre-confluent cultures the ability of these 2 cell types to accumulate amino acids was very similar. Post-confluent L-132 cells showed very little change from the pre-confluent cultures but the ability of MRC-5 cells in post-confluent cultures was greatly reduced. The intracellular concentrations of various amino acids necessary to achieve the maximum rate of protein synthesis were found. These values were identical for sparse and crowded cultures but due to the reduced uptake ability of crowded MRC-5 cells a far higher external amino acid concentration was required in post-confluent cultures. This meant that although amino acids did not become growth-limiting until over 80% utilized in pre-confluent cultures, in post-confluent cultures they became growth-limiting when only 50% utilized. Although protein synthesis was significantly affected by extracellular amino acid concentration and cell crowding, thus contributing towards the effect of contact inhibition of growth, DNA synthesis was shown to be the major metabolic function in contact inhibition. Increased cell density had a very inhibitory effect on DNA synthesis in MRC-5 cultures, but not in L-132 cultures, and this was unaffected by extracellular amino acid and glucose concentration.

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PHYTOCHEMICAL STATUS, ANTIBACTERIAL ACTIVITY AND ANTIOXIDANT PROPERTY OF DATURA METEL L.

International Journal of Current Pharmaceutical Research ◽

10.22159/ijcpr.2017.v9i3.19969 ◽

2017 ◽

Vol 9 (3) ◽

pp. 106

Author(s):

Jithu U. Krishnan ◽

Meera George ◽

Ajesh G.

Keyword(s):

Amino Acids ◽

Economic Value ◽

Ethanol Extract ◽

Antioxidant Property ◽

Phytochemical Analysis ◽

Plant Leaves ◽

Inhibition Of Growth ◽

Datura Metel ◽

Wide Range ◽

Phytochemical Profile

Objective: Medicinal plants are a source of great economic value all over the world and are on the front dusk of traditional medicine. Daturametel L, is one among the foresaid and this plant can be explored further as per its diversity of uses and on the basis of wide range of chemical compounds reported to be present in various parts of the plant. In the present investigation, Phyto-chemistry of D. metel has been analysed along with its antibacterial property.Methods: The selected plant leaves were collected and powdered. The bioactive compounds were extracted by using different solvents. Various phytochemical tests for alkaloids, flavonoids, saponins, steroids, terpenoids, tannins, glycosides and amino acids were done accordingly with standard protocol of testing. The study also extends to view the anti-bacterial potential by determining inhibition of growth using agar well diffusion method.Results: Phytochemical analysis reflected the presence of compounds like alkaloids, flavonoids, saponins, tannins, glycosides, and amino acids. It was noted that steroids and tannins are absent. Antimicrobial activity proves extract of ethanolis the most promising against the pathogens from the rest screened.Conclusion: Thearticle addresses, the undocumented knowledge regarding the phytochemical profile of D. metel which demand further exploration widely to serve Humanity. Antimicrobial potential of ethanol extract are very promising to deliver it as a pharmaceutical.

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In Vitro Study of the Effect of Osmotic Solutes on the Interactions between Cells from the Peritoneum and Peritoneal Cavity

Peritoneal Dialysis International ◽

10.1177/089686089401400210 ◽

1994 ◽

Vol 14 (2) ◽

pp. 149-154 ◽

Cited By ~ 8

Author(s):

Andrzej Breborowicz ◽

Elias Balaskas ◽

George D. Oreopoulos ◽

Leo Martis ◽

Kenneth Serkes ◽

...

Keyword(s):

Amino Acids ◽

Growth Factors ◽

Conditioned Medium ◽

In Vitro Study ◽

Mesothelial Cells ◽

Peritoneal Mesothelial Cells ◽

Inhibition Of Growth ◽

Peritoneal Leukocytes ◽

Osmotic Solutes

Objective To study how the presence of osmotic solutes in medium affects growth of the peritoneal mesothelial cells and fibroblasts and how osmotic solutes influence the production of factors regulating growth of these cells. Design The proliferation of mesothelial cells and fibroblasts was evaluated by measuring the incorporation of 3H-thymidine into the cells. Cells were exposed to osmotic solutes; the concentration of the latter in the medium was continuously lowered over the time of the experiment to simulate changes of their concentration in the dialysate. The synthesis of factors influencing the proliferation of the mesothelial cells or fibroblasts, by mesothelial cells or fibroblasts themselves, or by peritoneal leukocytes, was tested by the characteristics of the “conditioned” medium. The conditioned medium was produced by exposing standard medium to mesothelial or fibroblasts monolayer or to peritoneal leukocytes over 24 hours; following filtration it was applied to growing test cells for the study of growth factors. Results The effect of osmotic solutes on the growth of mesothelial cells is less inhibitory when their concentration is gradually lowered over the time of the study, compared to previous findings with a constant concentration. Peritoneal leukocytes produce growth factors for mesothelial cells and fibroblasts. Glucose and amino acids inhibit production of peritonealleukocyte-derived growth factors for mesothelial cells, while glycerol increases synthesis of such growth factors for fibroblasts. Mesothelial cells produce factors stimulating the proliferation of mesothelial cells and fibroblasts. In the presence of glycerol or amino acids synthesis of mesothelium derived growth factors for fibroblasts is augmented. Finally, fibroblasts produce factors that inhibit the proliferation of the mesothelial cells, and this effect is potentiated in the presence of amino acids. Conclusions Cytotoxicity of the osmotic solutes measured by the inhibition of growth of the mesothelial cells or their increased damage is significantly reduced during in vitro kinetic study when the concentration of these solutes is gradually lowered. Presence of osmotic solutes in the medium affects synthesis of growth factors derived from mesothelium, fibroblasts, or peritoneal leukocytes, which affect the proliferation of mesothelial cells or fibroblasts.

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Die Hemmung von Agrobacterium tumefaciens durch D-Aminosäuren

Zeitschrift für Naturforschung B ◽

10.1515/znb-1965-0914 ◽

1965 ◽

Vol 20 (9) ◽

pp. 899-905 ◽

Cited By ~ 11

Author(s):

Martin Bopp

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Agrobacterium Tumefaciens ◽

Nutrient Solution ◽

Complete Loss ◽

Inhibition Of Growth

The growth of Agrobacterium tumefaciens in nutrient solution can be inhibited by all ᴅ-amino acids used in these experiments. The degree of inhibition is of different in magnitude; in some cases the inhibition is complete. The inhibition is dependent on the concentration of ᴅ-amino acid and can not be counteracted by addition of L-amino acid or glycine; it is increased by K2CO3. After 28 transfers, all ᴅ-amino acid used in these experiments lead to reduction or complete loss of virulence. It can be assumed that ᴅ-amino acids induce independently loss of virulence and inhibition of growth.

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INHIBITION OF GROWTH OF PSEUDOMONAS DENITRIFICANS BY AMINO ACIDS

Canadian Journal of Microbiology ◽

10.1139/m66-149 ◽

1966 ◽

Vol 12 (6) ◽

pp. 1095-1098 ◽

Cited By ~ 9

Author(s):

Horace J. Daniels

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Basal Medium ◽

Ammonium Phosphate ◽

Complete Medium ◽

Mineral Salts ◽

Culture Studies ◽

Pseudomonas Denitrificans ◽

Inhibition Of Growth ◽

Amino Acid Mixtures

A large number of amino acids failed to support growth of Pseudomonas denitrificans in a basal medium composed of glucose, ammonium phosphate, and other mineral salts. Inability of an amino acid to support growth correlated well with its inhibitory action in a complete medium made up by adding L-glutamic acid to the basal medium. D-Amino acids were more toxic than the corresponding L-forms, and neutral amino acids were more toxic than acidic amino acids. Basic amino acids which were least toxic supported the best growth. The danger of the indiscriminate use of amino acid mixtures for culture studies is discussed.

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