Non-Human Toxicity Values
LD50 Rat (albino) oral >5000 mg/kg /EthylBloc, powdered product/
LD50 Rabbit (albino) dermal >2000 mg/kg /EthylBloc, powdered product/
LC50 Rat (albino) inhalation (4hr) >165 ppm /1-MCP gas/

[1]. 1-Methylcyclopropene treatment delays the softening of Actinidia arguta fruit by reducing cell wall degradation and modulating carbohydrate metabolism. Food Chem. 2023 Jun 15;411:135485.

[2]. Meta-analysis of the effects of 1-methylcyclopropene (1-MCP) treatment on climacteric fruit ripening. Hortic Res. 2020 Dec 3;7(1):208.

1-methylcyclopropene is a member of the class of cyclopropenes that is cyclopropene in which the hydrogen at position 1 has been replaced by a methyl group. A gas at room temperture and pressure, it is a (synthetic) ethylene perception inhibitor and is used to prolong the life of cut and potted flowers, other ornamental plants, and fruit. It has a role as a plant growth regulator and an agrochemical. It is a member of cyclopropenes and a cycloalkene.
1-Methylcyclopropene has been reported in Prunus avium with data available.

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Mechanism of Action
1-MCP has a mode of action in plants which is a non-persistent and non-toxic mode of action. 1-MCP prevents the natural chemical, ethylene, from binding to ethylene receptors in plants. This mode of action is not relevant in animals, since ethylene receptors are not present in animal tissues.
It was first noted that 2, 5-norbornadiene seemed to counteract ethylene. Studies showed it was a competitive inhibitor of ethylene responses, and knowledge that ethylene antagonists like ethylene agonists bound to silver in the same order as they were active as inhibitors was obtained. Ring strain appeared to be a primary factor that led to trans-cyclooctene then to diazocyclopentadiene. This same concept allowed for the use of chemical concepts that lead to cyclopropenes. More recent work indicates additional factors can come into play in the development of ethylene antagonists at the receptor level and these are now being utilized to find additional and improved antagonists. 1-MCP is likely to remain a primary means of controlling ethylene responses for the immediate future.
Volatile esters are major aroma components of apple, and an alcohol acyltransferase (AAT) catalyzes the final step in ester biosynthesis. The gene MdAAT2, which encodes a predicted 51.2 kDa protein containing features of other acyl transferases, was isolated from Malus domestica Borkh. (cv. Golden Delicious). In contrast to other apple varieties, the MdAAT2 gene of Golden Delicious is exclusively expressed in the fruit. The MdAAT2 protein is about 47.9 kDa and mainly localized in the fruit peel, as indicated by immunoblot and immunolocalization analysis. Northern blot and immunoblot analysis showed that the transcription and translation of MdAAT2 have a positive correlation with apple AAT enzyme activity and ester production, except in the later ripening stage, suggesting that MdAAT2 is involved in the regulation of ester biosysthesis and that a post-translation modification may be involved in regulation of AAT enzyme activity. Tissue disk assays of fruit peel revealed that using extraneous alcohols can recover the corresponding ester formation. Transcription and translation of MdAAT2 were both depressed by 1-methylcyclopropene (1-MCP) treatment and subsequent ester production was also prevented. These results suggest that: (1) ester production is mainly regulated by MdAAT2; (2) ethylene is also involved in this regulatory progress and (3) ester compounds rely principally on the availability of substrates.
By screening for ethylene response mutants in Arabidopsis, a novel mutant, eer2, was isolated which displays enhanced ethylene responses. On a low nutrient medium (LNM) light-grown eer2 seedlings showed a significant hypocotyl elongation in response to low levels of 1-amino-cyclopropane-1-carboxylate (ACC), the precursor of ethylene, compared with the wild type, indicating that eer2 is hypersensitive to ethylene. Treatment with 1-MCP (1-methylcyclopropene), a competitive inhibitor of ethylene signalling, suppressed this hypersensitive response, demonstrating that it is a bona fide ethylene effect. By contrast, roots of eer2 were less sensitive than the wild type to low concentrations of ACC. The ethylene levels in eer2 did not differ from the wild type, indicating that ethylene overproduction is not the primary cause of the eer2 phenotype. In addition to its enhanced ethylene response of hypocotyls, eer2 is also affected in the pattern of senescence and its phenotype depends on the nutritional status of the growth medium. Furthermore, linkage analysis of eer2 suggests that this mutant defines a new locus in ethylene signalling.
Auxin, which has been implicated in multiple biochemical and physiological processes, elicits three classes of genes (Aux/IAAs, SAURs and GH3s) that have been characterized by their early or primary responses to the hormone. A new GH3-like gene was identified from a suppressive subtraction hybridization (SSH) library of pungent pepper (Capsicum chinense L.) cDNAs. This gene, CcGH3, possessed several auxin- and ethylene-inducible elements in the putative promoter region. Upon further investigation, CcGH3 was shown to be auxin-inducible in shoots, flower buds, sepals, petals and most notably ripening and mature pericarp and placenta. Paradoxically, this gene was expressed in fruit when auxin levels were decreasing, consistent with ethylene-inducibility. Further experiments demonstrated that CcGH3 was induced by endogenous ethylene, and that transcript accumulation was inhibited by 1-methylcyclopropene, an inhibitor of ethylene perception. When over-expressed in tomato, CcGH3 hastened ripening of ethylene-treated fruit. These results implicate CcGH3 as a factor in auxin and ethylene regulation of fruit ripening and suggest that it may be a point of intersection in the signaling by these two hormones.

C4H6

54.09

54.046

3100-04-7

151080

Gas

0.8±0.1 g/cm3

6.8±7.0 °C at 760 mmHg

-72.5±6.6 °C

1435.2±0.0 mmHg at 25°C

1.474

1.79

0

0

0

4

51.1

0

CC1=CC1

SHDPRTQPPWIEJG-UHFFFAOYSA-N

InChI=1S/C4H6/c1-4-2-3-4/h2H,3H2,1H3

1-methylcyclopropene

1-Methylcyclopropene; 1-MCP

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)