Potassium Sorbate Inhibition of Microorganisms Isolated from Seafood1

1982 ◽  
Vol 45 (14) ◽  
pp. 1310-1313 ◽  
Author(s):  
YUH-MEI CHUNG ◽  
J. S. LEE
Keyword(s):  
Inhibitory Concentration ◽  
Basal Medium ◽  
Inhibitory Effect ◽  
Potassium Sorbate ◽  
Inhibitory Effects ◽  
Freeze Thaw ◽  
Inhibition Of Growth ◽  
Heat Treated ◽  
Lag Period ◽  
Logarithmic Growth

Microorganisms isolated from seafood showed various degrees of sensitivity toward potassium sorbate (PS). At pH 7.0, PS concentration of 0.53% completely inhibited growth of Moraxella sp., while 2.73% was needed to inhibit Arthrobacter sp. Pseudomonas I sp., which was relatively resistant to PS (inhibitory concentration = 1.62%), was not affected by 0.3% PS after freeze-thaw treatment (−78°C for 8 min and 20°C for 20 min), but showed a delay in onset of logarithmic growth for up to 20 h after heating at 50°C for 5 min. The inhibitory effect of PS on sub-lethally injured Pseudomonas I was greater in basal medium (Minimum Broth, Davis) than in a rich medium (tryptone-peptone-extract, TPE). Alteromonas putrefaciens, which was sensitive to PS (inhibitory concentration = 0.74%), was also sensitive to freeze-thaw and mild heat. The lag period for quick-frozen cells was extended by 14 h in the presence of 0.05% PS. Heating at 45°C for 10 sec was sufficient to cause complete inhibition of growth by 0.05% PS in MBD, and 8 h delay in the onset of logarithmic growth in TPE. Selective and inhibitory effects of PS, therefore, could be further enhanced in frozen or heat-treated seafood.

scholarly journals In Vitro α-Glucosidase and α-Amylase Inhibitory Activities of Free and Bound Phenolic Extracts from the Bran and Kernel Fractions of Five Sorghum Grain Genotypes

Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1301
Author(s):  
Yun Xiong ◽  
Ken Ng ◽  
Pangzhen Zhang ◽  
Robyn Dorothy Warner ◽  
Shuibao Shen ◽  
...  
Keyword(s):  
Digestive System ◽  
Inhibitory Concentration ◽  
Inhibitory Effect ◽  
Inhibitory Effects ◽  
Phenolic Contents ◽  
Inhibitory Activities ◽  
Sorghum Grain ◽  
Global Health Challenge ◽  
Phenolic Extracts

Diabetes is a global health challenge. Currently, an effective treatment for diabetes is to reduce the postprandial hyperglycaemia by inhibiting the carbohydrate hydrolysing enzymes in the digestive system. In this study, we investigated the in vitro α-glucosidase and α-amylase inhibitory effects of free and bound phenolic extracts, from the bran and kernel fractions of five sorghum grain genotypes. The results showed that the inhibitory effect of sorghum phenolic extracts depended on the phenolic concentration and composition. Sorghum with higher phenolic contents generally had higher inhibitory activity. Among the tested extracts, the brown sorghum (IS131C)-bran-free extract (BR-bran-free, half-maximal inhibitory concentration (IC50) = 18 ± 11 mg sorghum/mL) showed the strongest inhibition against α-glucosidase which was comparable to that of acarbose (IC50 = 1.39 ± 0.23 mg acarbose/mL). The red sorghum (Mr-Buster)-kernel-bound extract (RM-kernel-bound, IC50 = 160 ± 12 mg sorghum/mL) was the most potent in inhibiting α-amylase but was much weaker compared to acarbose (IC50 = 0.50 ± 0.03 mg acarbose/mL).

Effect of Sucrose Esters in Combination with Selected Mold Inhibitors on Growth and Aflatoxin Production by Aspergillus parasiticus1

1986 ◽  
Vol 49 (5) ◽  
pp. 378-382 ◽  
Author(s):  
DOUGLAS L. MARSHALL ◽  
LLOYD B. BULLERMAN
Keyword(s):  
Fold Increase ◽  
Aflatoxin Production ◽  
Sucrose Ester ◽  
Potassium Sorbate ◽  
Sucrose Esters ◽  
Inhibitory Effects ◽  
Ph Values ◽  
Inhibition Of Growth ◽  
Calcium Propionate ◽  
Low Levels

The effects of sucrose esterified with a mixture of palmitic and stearic acids (commonly referred to as sucrose ester) in combination with cinnamon, potassium sorbate, or calcium propionate on growth of and aflatoxin production by Aspergillus parasiticus was studied in broths at two pH values. Cinnamon in combination with sucrose ester did not result in additive or synergistic inhibitory effects on growth or aflatoxin production. At pH 4.0, subinhibitory amounts of cinnamon were stimulatory toward growth and antagonistic to inhibition of growth by sucrose ester. Complete inhibition of growth and aflatoxin production was observed with a cinnamon level of 1.0%, alone and in combination with sucrose ester. Low levels (0.1%) of calcium propionate or potassium sorbate combined with sucrose ester did not enhance inhibition of growth or aflatoxin production. A synergistic effect on inhibition of growth was observed with high levels of propionate or sorbate in combination with sucrose ester, while aflatoxin production remained relatively unaffected. However, subinhibitory levels of propionate resulted in a 10-fold increase of aflatoxin production and a shift in the ratio of aflatoxin B1 and G1, from 1:1 to 1:8. Subinhibitory levels of sorbate also caused a stimulation of aflatoxin production during the latter stages of incubation, though to a lesser degree than propionate.

Inhibitory Effects of Various Salts and/or Ionic Strengths on Growth from Clostridium botulinum 52A Spores or Vegetative Cells

1985 ◽  
Vol 48 (5) ◽  
pp. 421-428 ◽  
Author(s):  
M. K. WAGNER ◽  
F. F. BUSTA
Keyword(s):  
Ionic Strength ◽  
Clostridium Botulinum ◽  
Potassium Sorbate ◽  
Chloride Salt ◽  
Inhibitory Effects ◽  
Vegetative Cells ◽  
Inhibition Of Growth ◽  
The Mean ◽  
Ph Level ◽  
Peptone Yeast Extract Glucose

Growth response from spores and vegetative cells of Clostridium botulinum strain 52A in peptone-yeast extract-glucose (PYEG) broth at two pH levels (5.55 or 5.85) containing sodium acid pyrophosphate (SAPP) (0, 0.2, 0.4%), NaCl (0, 1.25, 2.50%) and/or potassium sorbate (KS) (0, 0.13, 0.26%) was measured as the mean A630 nm of 20 tubes at 37°C. Additional treatments contained KC1 and MgCl2 (0, 1.25, 2.50%) without SAPP or KS. Growth ratios (GR = treatment/control) based on time to reach A630 = 0.35 were calculated to compare effects of additives on strain 52A. Growth from spores was affected significantly (p≤0.01) by pH level. KS and KS/pH interactions were also significant factors in growth from both spores and vegetative cells; SAPP/pH interactions were significant for cell growth, only. Combinations of SAPP (0.2, 0.4%) NaCl (0%) and KS (0.26%) were the most favorable treatments for delaying growth from spores or vegetative cells. NaCl (1.25, 2.50%) decreased antibotulinal effects produced by combinations of SAPP and KS. Elimination of NaCl enhanced antibotulinal effects. Formulations containing KC1 or MgCl2 (without SAPP and KS) at the same molarity as the NaCl in earlier treatments (0.21, 0.43) resulted in inhibition of growth from vegetative cells greater than growth from spores in the presence of MgCl2 at M = 0.43 (ionic strength = 1.29). This inhibition was more evident at pH 5.55 than pH 5.85. This study in a model system suggests ionic strength and/or chloride salt may be important considerations when manipulating formulations of additives designed to control C. botulinum growth.

scholarly journals A study of suitability of some conventional chemical preservatives and natural antimicrobial compounds in allelopathic research

2015 ◽  
Vol 30 (4) ◽  
pp. 233-241
Author(s):  
Plamen Marinov-Serafimov ◽  
Irena Golubinova
Keyword(s):  
Inhibitory Effect ◽  
Potassium Sorbate ◽  
Antimicrobial Compound ◽  
Inhibitory Effects ◽  
Natural Antimicrobial ◽  
Initial Development ◽  
Fresh Biomass ◽  
Lactuca Sativa L ◽  
Chemical Preservatives ◽  
The Impact

The impact of three conventional chemical preservatives (sodium benzoate, potassium sorbate and salicylic acid) and a natural antimicrobial compound (thymol) on germination, dynamics of growth and accumulation of fresh biomass (g per seedling) of Lactuca sativa L., cultivar Great Lakes, was studied under laboratory conditions. The tested conventional chemical preservatives demonstrated strong inhibitory effects (GI 27.1-0.0%) on germination and initial development of L. sativa, and they cannot be used in allelopathic studies in the laboratory. An addition of thymol at 0.5-1.0 ? concentration showed no inhibitory effect (GI varied 81.7-84.6%) on germination and initial development of L. sativa. Thymol can therefore be used as a natural antimicrobial compound in allelopathic studies in the laboratory.

Inhibition of Microbial Growth in English Sole (Parophrys retulus)1

1981 ◽  
Vol 44 (1) ◽  
pp. 66-68 ◽  
Author(s):  
YUH-MEI CHUNG ◽  
J. S. LEE
Keyword(s):  
Generation Time ◽  
Maximum Level ◽  
Maximum Growth ◽  
Potassium Sorbate ◽  
English Sole ◽  
Untreated Sample ◽  
C Storage ◽  
Treated Sample ◽  
Lag Period ◽  
Logarithmic Growth

The influence of potassium sorbate on growth of microorganisms in seafood was tested by treating English sole (Parophrys retulus) homogenate with 0, 0.1 and 1.0% potassium sorbate. Viable counts during 1.1-C storage revealed that 0.1% potassium sorbate delayed the onset of logarithmic growth of bacteria for 1 day compared to no delay for the untreated control. The generation time of 1.7 days and a maximum growth level of 109 cells per g were unchanged by the presence of 0.1% potassium sorbate. The 1.0% sorbate treatment extended the lag period to 6 days. The generation time was increased to 2.1 days and the maximum level of growth reached was 107 cells per g on the 14th day. Tests of the microbial flora of the fish revealed that Pseudomonas spp., which comprised 17.1 %of the total at 0 day, increased to 96.0% of the microbial population in 14 days at 1.1 C for the untreated sample. During the same period the Pseudomonas population reached 100% for the 0.1% sorbate-treated sample, and to 98.2% for the 1.0% sorbate-treated sample. Potassium sorbate at the concentrations employed, therefore, did not seem to alter the typical microbial spoilage pattern.

In Vitro Effects of Ethanol on Rabbit Platelet Aggregation, Secretion of Granule Contents, and Cyclic AMP Levels in the Presence of Prostacyclin

1989 ◽  
Vol 61 (02) ◽  
pp. 254-258 ◽  
Author(s):  
Margaret L Rand ◽  
Peter L Gross ◽  
Donna M Jakowec ◽  
Marian A Packham ◽  
J Fraser Mustard
Keyword(s):  
Cyclic Amp ◽  
Inhibitory Effect ◽  
Rabbit Platelet ◽  
Inhibitory Effects ◽  
Low Concentrations ◽  
Rabbit Platelets ◽  
High Concentrations ◽  
In Vitro Effects ◽  
Aggregation Of Platelets

SummaryEthanol, at physiologically tolerable concentrations, inhibits platelet responses to low concentrations of collagen or thrombin, but does not inhibit responses of washed rabbit platelets stimulated with high concentrations of ADP, collagen, or thrombin. However, when platelet responses to high concentrations of collagen or thrombin had been partially inhibited by prostacyclin (PGI2), ethanol had additional inhibitory effects on aggregation and secretion. These effects were also observed with aspirin- treated platelets stimulated with thrombin. Ethanol had no further inhibitory effect on aggregation of platelets stimulated with ADP, or the combination of ADP and epinephrine. Thus, the inhibitory effects of ethanol on platelet responses in the presence of PGI2 were very similar to its inhibitory effects in the absence of PGI2, when platelets were stimulated with lower concentrations of collagen or thrombin. Ethanol did not appear to exert its inhibitory effects by increasing cyclic AMP above basal levels and the additional inhibitory effects of ethanol in the presence of PGI2 did not appear to be brought about by further increases in platelet cyclic AMP levels.

Inhibition of ADP-Induced Responses in Human Platelets by Agents Elevating the Cyclic AMP Level: Comparison of Aggregation and Shape Change

1984 ◽  
Vol 52 (03) ◽  
pp. 333-335 ◽  
Author(s):  
Vider M Steen ◽  
Holm Holmsen
Keyword(s):  
Inhibitory Action ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Shape Change ◽  
Inhibitory Effect ◽  
Human Platelets ◽  
Inhibitory Effects ◽  
Early Step ◽  
Stimulus Response ◽  
Sequential Relationship

SummaryThe inhibitory effect of cAMP-elevating agents on shape change and aggregation in human platelets was studied to improve the understanding of the sequential relationship between these two responses.Human platelet-rich plasma was preincubated for 2 min at 37° C with prostaglandin E1 or adenosine, agents known to elevate the intracellular level of cAMP. Their inhibitory effects on ADP-induced shape change and aggregation were determined both separately and simultaneously. The dose-inhibition patterns for shape change and aggregation were similar for both PGE1 and adenosine. There was no distinct difference between the inhibitory action of these two inhibitors.These observations suggest that elevation of the intracellular concentration of cAMP interferes with an early step in the stimulus-response coupling that is common for aggregation and shape change.

The Inhibitory Effect of Heparin and Related Glycosaminoglycans on Neutrophil Chemotaxis

1984 ◽  
Vol 52 (02) ◽  
pp. 134-137 ◽  
Author(s):  
Yaacov Matzner ◽  
Gerard Marx ◽  
Ruth Drexler ◽  
Amiram Eldor
Keyword(s):  
Specific Binding ◽  
Anticoagulant Activity ◽  
Neutrophil Migration ◽  
Inhibitory Effect ◽  
Chemotactic Factor ◽  
Human Neutrophils ◽  
Boyden Chamber ◽  
Neutrophil Chemotaxis ◽  
Inhibitory Effects ◽  
Chemotactic Factors

SummaryClinical observations have shown that heparin has antiinflammatory activities. The effect of heparin on neutrophil chemotaxis was evaluated in vitro in the Boyden Chamber. This method enabled differentiation between the direct effects of heparin on neutrophil migration and locomotion, and its effects on chemotactic factors. Heparin inhibited both the random migration and directed locomotion of human neutrophils toward zymosan-activated serum (ZAS) and F-met-leu-phe (FMLP). Inhibition was found to be dependent on the concentrations of the heparin and of the chemotactic factors. No specific binding of heparin to the neutrophils could be demonstrated, and heparin’s inhibitory effects were eliminated by simple washing of the cells. When added directly to the chamber containing chemotactic factor, heparin inhibited the chemotactic activity of ZAS but not that of FMLP, suggesting a direct inhibitory effect against C5a, the principal chemotactic factor in ZAS.Experiments performed with low-molecular-weight heparin, N-desulfated heparin, dextran sulfate, chondroitin sulfate and dextran indicated that the inhibitory effects of heparin on neutrophil chemotaxis are not related to its anticoagulant activity, but probably depend on the degree of sulfation of the heparin molecule.

Inhibition of Yeast Growth by Tryptamine and Recovery with Tryptophan

2020 ◽  
Vol 16 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Chandrika Kadkol ◽  
Ian Macreadie
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Source ◽  
Competitive Inhibition ◽  
Yeast Species ◽  
Inhibitory Effect ◽  
The Body ◽  
Inhibitory Effects ◽  
Trna Synthetases ◽  
Fermentative Growth ◽  
Biogenic Monoamine

Background: Tryptamine, a biogenic monoamine that is present in trace levels in the mammalian central nervous system, has probable roles as a neurotransmitter and/or a neuromodulator and may be associated with various neuropsychiatric disorders. One of the ways tryptamine may affect the body is by the competitive inhibition of the attachment of tryptophan to tryptophanyl tRNA synthetases. Methods: This study has explored the effects of tryptamine on growth of six yeast species (Saccharomyces cerevisiae, Candida glabrata, C. krusei, C. dubliniensis, C. tropicalis and C. lusitaniae) in media with glucose or ethanol as the carbon source, as well as recovery of growth inhibition by the addition of tryptophan. Results: Tryptamine was found to have an inhibitory effect on respiratory growth of all yeast species when grown with ethanol as the carbon source. Tryptamine also inhibited fermentative growth of Saccharomyces cerevisiae, C. krusei and C. tropicalis with glucose as the carbon source. In most cases the inhibitory effects were reduced by added tryptophan. Conclusion: The results obtained in this study are consistent with tryptamine competing with tryptophan to bind mitochondrial and cytoplasmic tryptophanyl tRNA synthetases in yeast: effects on mitochondrial and cytoplasmic protein synthesis can be studied as a function of growth with glucose or ethanol as a carbon source. Of the yeast species tested, there is variation in the sensitivity to tryptamine and the rescue by tryptophan. The current study suggests appropriate yeast strains and approaches for further studies.

Molecular Mechanisms of the Inhibitory Effects of Bupivacaine, Levobupivacaine, and Ropivacaine on Sarcolemmal Adenosine Triphosphate–sensitive Potassium Channels in the Cardiovascular System

2004 ◽  
Vol 101 (2) ◽  
pp. 390-398 ◽  
Author(s):  
Takashi Kawano ◽  
Shuzo Oshita ◽  
Akira Takahashi ◽  
Yasuo Tsutsumi ◽  
Yoshinobu Tomiyama ◽  
...  
Keyword(s):  
Cardiovascular System ◽  
Adenosine Triphosphate ◽  
Local Anesthetics ◽  
Molecular Mechanisms ◽  
Transmembrane Domain ◽  
Katp Channels ◽  
Inhibitory Effect ◽  
Amino Acid Residues ◽  
Sulfonylurea Receptor ◽  
Inhibitory Effects

Background Sarcolemmal adenosine triphosphate-sensitive potassium (KATP) channels in the cardiovascular system may be involved in bupivacaine-induced cardiovascular toxicity. The authors investigated the effects of local anesthetics on the activity of reconstituted KATP channels encoded by inwardly rectifying potassium channel (Kir6.0) and sulfonylurea receptor (SUR) subunits. Methods The authors used an inside-out patch clamp configuration to investigate the effects of bupivacaine, levobupivacaine, and ropivacaine on the activity of reconstituted KATP channels expressed in COS-7 cells and containing wild-type, mutant, or chimeric SURs. Results Bupivacaine inhibited the activities of cardiac KATP channels (IC50 = 52 microm) stereoselectively (levobupivacaine, IC50 = 168 microm; ropivacaine, IC50 = 249 microm). Local anesthetics also inhibited the activities of channels formed by the truncated isoform of Kir6.2 (Kir6.2 delta C36) stereoselectively. Mutations in the cytosolic end of the second transmembrane domain of Kir6.2 markedly decreased both the local anesthetics' affinity and stereoselectivity. The local anesthetics blocked cardiac KATP channels with approximately eightfold higher potency than vascular KATP channels; the potency depended on the SUR subtype. The 42 amino acid residues at the C-terminal tail of SUR2A, but not SUR1 or SUR2B, enhanced the inhibitory effect of bupivacaine on the Kir6.0 subunit. Conclusions Inhibitory effects of local anesthetics on KATP channels in the cardiovascular system are (1) stereoselective: bupivacaine was more potent than levobupivacaine and ropivacaine; and (2) tissue specific: local anesthetics blocked cardiac KATP channels more potently than vascular KATP channels, via the intracellular pore mouth of the Kir6.0 subunit and the 42 amino acids at the C-terminal tail of the SUR2A subunit, respectively.

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