Alicyclic Alcohols Research Articles

Scientific Opinion on Flavouring Group Evaluation 73, Revision 3 (FGE.73Rev3): Consideration of alicyclic alcohols, aldehydes, acids and related esters evaluated by JECFA (59th and 63rd meeting) structurally related to primary saturated or unsaturated ali

Scientific Opinion on Flavouring Group Evaluation 73, Revision 3 (FGE.73Rev3): Consideration of alicyclic alcohols, aldehydes, acids and related esters evaluated by JECFA (59th and 63rd meeting) structurally related to primary saturated or unsaturated ali

Scientific Opinion on Flavouring Group Evaluation 9, Revision 5 (FGE.09Rev5): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivat

Scientific Opinion on Flavouring Group Evaluation 9, Revision 5 (FGE.09Rev5): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivat

Scientific Opinion on Flavouring Group Evaluation 73, Revision 2 (FGE.73Rev2): Consideration of alicyclic primary alcohols, aldehydes, acids and related esters evaluated by JECFA (59th meeting) structurally related to primary saturated or unsaturated alicyclic alcohols, aldehydes, acids and esters evaluated by EFSA in FGE.12Rev3 (2012)

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA), and to decide whether further evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present consideration concerns a group of 17 alicyclic primary alcohols, aldehydes, acids and related esters and one phenethyl ester evaluated by the JECFA at the 59th meeting in 2002. This revision is made due to consideration of two additional substances, santalyl acetate [FL-no: 09.034] and santalyl phenylacetate [FL-no: 09.712], cleared for genotoxicity concern in FGE.207. The substances were evaluated through a stepwise approach that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel agrees with the application of the Procedure as performed by the JECFA for all 18 substances [FL-no: 02.114, 02.141, 05.098, 05.104, 05.112, 05.119, 05.123, 08.034, 08.060, 08.067, 09.028, 09.034, 09.289, 09.488, 09.534, 09.536, 09.615 and 09.712], considered in this FGE and agrees with the JECFA conclusion, “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for all 18 substances, the information is adequate.

Scientific Opinion on Flavouring Group Evaluation 12, Revision 4 (FGE.12Rev4): primary saturated or unsaturated alicyclic alcohols, aldehydes, acids and esters from chemical groups 1 and 7

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 12 flavouring substances in Flavouring Group Evaluation 12, Revision 4 (FGE.12Rev4), including two additional substances, using the Procedure in Commission Regulation (EC) No 1565/2000. The present revision includes two additional flavouring substances: 12-beta-santalen-14-ol [FL-no: 02.216] and 12-alpha-santalen-14-ol [FL-no: 02.217]. None of the substances was considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses and the toxicological threshold of concern and available data on metabolism and toxicity. The Panel concluded that none of the 12 substances [FL-nos: 02.134, 02.186, 02.216, 02.217, 05.157, 05.182, 05.183, 05.198, 08.135, 09.342, 09.670 and 09.829] gives rise to safety concerns at their levels of dietary intake, estimated on the basis of the maximised survey-derived daily intake approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all 12 candidate substances.

Characterization of rabbit morphine 6-dehydrogenase and two NAD+-dependent 3α(17β)-hydroxysteroid dehydrogenases

Mammalian morphine 6-dehydrogenase (M6DH)1Abbreviations used: M6DH, morphine 6-dehydrogenase; AKR, aldo-keto reductase; HSD, hydroxysteroid dehydrogenase; TBE, 6-tert-butyl-2,3-epoxy-4-hydroxy-5-cyclohexen-1-one; RT, reverse transcription; S-tetralol, S-(+)-1,2,3,4-tetrahydro-1-naphthol; BAEC, bovine aortic endothelial cell; LC/MS, liquid chromatography/mass spectrometry.1 converts morphine into a reactive electrophile, morphinone. M6DH belongs to the aldo–keto reductase (AKR) superfamily, but its endogenous substrates and entire amino acid sequence remain unknown. A recent rabbit genomic sequencing predicts three genes for novel AKRs (1C26, 1C27 and 1C28) that share >87% amino acid sequence identity and are similar to the partial sequence of rabbit liver M6DH. We isolated cDNAs for the three AKRs, and compared the properties of their recombinant enzymes. Like M6DH, only AKR1C26 that shares the highest sequence identity with hepatic M6DH oxidized morphine. The three AKRs showed NAD+-dependent dehydrogenase activity towards other non-steroidal alicyclic alcohols and 3α/17β-hydroxy-C18/C19/C21-steroids, and their mRNAs were ubiquitously expressed in rabbit tissues. The kinetic constants for the substrates suggest that at least AKR1C26 and AKR1C28 act as NAD+-dependent 3α/17β-hydroxysteroid dehydrogenases. AKR1C27 differed from AKR1C28 in its high Km values for the substrates and low sensitivity towards competitive inhibitors (ikarisoside A, hinokitiol, hexestrol and zearalenone), despite their 95% sequence identity. The site-directed mutagenesis of Tyr118 and Phe310 in AKR1C27 to the corresponding residues (Phe and Ile, respectively) in AKR1C28 produced an enzyme that was similar to AKR1C28, suggesting their key roles in ligand binding.

Scientific Opinion on Flavouring Group Evaluation 12, Revision 3 (FGE.12Rev3): Primary saturated or unsaturated alicyclic alcohol, aldehyde, acid, and esters from chemical group 7

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 10 flavouring substances in the Flavouring Group Evaluation 12 (FGE.12), including an additional substance in revision 3, using the Procedure in Commission Regulation (EC) No 1565/2000. This revision is made due to inclusion of one additional flavouring substance, 2,6,6-trimethylcyclohex-2-ene-1-carboxaldehyde [FL-no: 05.182]. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel concluded that all 10 substances [FL-no: 02.134, 02.186, 05.157, 05.182, 05.183, 05.198, 08.135, 09.342, 09.670 and 09.829] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all 10 candidate substances.

Scientific Opinion on Flavouring Group Evaluation 9, Revision 4 (FGE.09Rev4): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivative from chemical group 25

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 21 flavouring substances in the Flavouring Group Evaluation 9, Revision 4, using the Procedure in Commission Regulation (EC) No 1565/2000. The present revision of FGE.09 includes the assessment of four additional flavouring substances, p-menthan-3-one [FL-no: 07.059], 2,6,6-trimethylcyclohex-2-en-1-one [FL-no: 07.202], l-piperitone [FL-no: 07.255] and menthol 1-and 2-propylene glycol carbonate [FL-no: 09.843]. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel concluded that the 20 substances [FL-no: 02.070, 02.075, 02.135, 02.167, 06.136, 07.059, 07.202, 07.203, 07.255, 09.154, 09.355, 09.520, 09.618, 09.619, 09.621, 09.843, 09.870, 09.929, 09.935 and 09.949] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. For the remaining candidate substance [FL-no: 07.207], additional toxicity data are requested (further metabolism and/or toxicity studies). Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all candidate substances.

Scientific Opinion on Flavouring Group Evaluation 73, Revision 1 (FGE.73Rev1): Consideration of alicyclic primary alcohols, aldehydes, acids and related esters evaluated by JECFA (59th meeting) structurally related to primary saturated or unsaturated alicyclic alcohol, aldehyde, and esters evaluated by EFSA in FGE.12Rev2 (2011)

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA), and to decide whether further evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present consideration concerns a group of 16 alicyclic primary alcohols, aldehydes, acids and related esters evaluated by the JECFA at the 59th meeting in 2002. The revision is made due to consideration of one additional substance compared to the previous version. The substances were evaluated through a stepwise approach that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel agrees with the application of the Procedure as performed by the JECFA for all 16 substances [FL-no: 02.114, 02.141, 05.098, 05.104, 05.112, 05.119, 05.123, 08.034, 08.060, 08.067, 09.028, 09.289, 09.488, 09.534, 09.536 and 09.615], considered in this FGE and agrees with the JECFA conclusion, “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for all 16 substances, the information is adequate.

Crystal structure of a ring-cleaving cyclohexane-1,2-dione hydrolase, a novel member of the thiamine diphosphate enzyme family

The thiamine diphosphate (ThDP) dependent flavoenzyme cyclohexane-1,2-dione hydrolase (CDH) (EC 3.7.1.11) catalyses a key step of a novel anaerobic degradation pathway for alicyclic alcohols by converting cyclohexane-1,2-dione (CDO) to 6-oxohexanoate and further to adipate using NAD(+) as electron acceptor. To gain insights into the molecular basis of these reactions CDH from denitrifying anaerobe Azoarcus sp. strain 22Lin was structurally characterized at 1.26 Å resolution. Notably, the active site funnel is rearranged in an unprecedented manner providing the structural basis for the specific binding and cleavage of an alicyclic compound. Crucial features include a decreased and displaced funnel entrance, a semi-circularly shaped loop segment preceding the C-terminal arm and the attachment of the C-terminal arm to other subunits of the CDH tetramer. Its structural scaffold and the ThDP activation is related to that observed for other members of the ThDP enzyme family. The selective binding of the competitive inhibitor 2-methyl-2,4-pentane-diol (MPD) to the open funnel of CDH reveals an asymmetry of the two active sites found also in the dimer of several other ThDP dependent enzymes. The substrate binding site is characterized by polar and non-polar moieties reflected in the structures of MPD and CDO and by three prominent histidine residues (His28, His31 and His76) that most probably play a crucial role in substrate activation. The NAD(+) dependent oxidation of 6-oxohexanoate remains enigmatic as the redox-active cofactor FAD seems not to participate in catalysis, and no obvious NAD(+) binding site is found. Based on the structural data both reactions are discussed.

Scientific Opinion on Flavouring Group Evaluation 9, Revision 3 (FGE.09Rev3): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivative from chemical group 25

The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 17 flavouring substances in the Flavouring Group Evaluation 9, Revision 3, using the Procedure in Commission Regulation (EC) No 1565/2000. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel concluded that the 16 substances [FL-no: 02.070, 02.075, 02.135, 02.167, 06.136, 07.203, 09.154, 09.355, 09.520, 09.618, 09.619, 09.621, 09.870, 09.929, 09.935 and 09.949] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. For the remaining candidate substance [FL-no: 07.207] additional toxicity data are requested (further metabolism and/or toxicity studies). Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all 17 candidate substances.

Scientific Opinion on Flavouring Group Evaluation 12, Revision 2 (FGE.12Rev2): Primary saturated or unsaturated alicyclic alcohol, aldehyde, acid, and esters from chemical group 7

Scientific Opinion on Flavouring Group Evaluation 12, Revision 2 (FGE.12Rev2): Primary saturated or unsaturated alicyclic alcohol, aldehyde, acid, and esters from chemical group 7

Expanding the gelation properties of valine-based 3,5-diaminobenzoate organogelators with N-alkylurea functionalities

A new family of valine-containing 3,5-diaminobenzoate derivatives 2 with N-alkylurea moieties attached to the valine moieties was prepared. By appending these two new N-alkylurea chains to the molecular structure, their organogelating properties were extended from only aromatic solvents, to a wide range of other types of solvents such as alicyclic hydrocarbons, alcohols and polar solvents such as DMSO and DMF. It was also found that a longer N-alkylurea chain conferred improved gelation power and higher thermal stability as compared to those of the shorter ones.

ChemInform Abstract: A Convenient Preparation of Ketones by the Oxidation of Secondary Alcohols with Chromium(VI) Trioxide in Aprotic Solvent in the Presence of “Wet”-Aluminum Oxide.

The oxidation of aliphatic and alicyclic secondary alcohols with chromium(VI) trioxide in the presence of “wet”-aluminum oxide in hexane gave the corresponding ketones in excellent yields under mild conditions.

Flavouring Group Evaluation 9, Revision 2 (FGE.09Rev2): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivative from chemical grou

Flavouring Group Evaluation 9, Revision 2 (FGE.09Rev2): Secondary alicyclic saturated and unsaturated alcohols, ketones and esters containing secondary alicyclic alcohols from chemical group 8 and 30, and an ester of a phenol derivative from chemical grou

Flavouring Group Evaluation 89 (FGE.89): Consideration of phenyl‐substituted aliphatic tertiary alcohols and related aldehydes and esters evaluated by JECFA (63rd and 68th meetings) structurally related to aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols, aromatic tertiary alcohols and their esters evaluated by EFSA in FGE.18Rev1 (2009)

Flavouring Group Evaluation 89 (FGE.89): Consideration of phenyl‐substituted aliphatic tertiary alcohols and related aldehydes and esters evaluated by JECFA (63rd and 68th meetings) structurally related to aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols, aromatic tertiary alcohols and their esters evaluated by EFSA in FGE.18Rev1 (2009)

Flavouring Group Evaluation 70 (FGE.70): Consideration of aliphatic, alicyclic, linear, alpha, beta‐unsaturated, di‐ and trienals and related alcohols, acids and esters evaluated by JECFA (61st meeting)

Flavouring Group Evaluation 70 (FGE.70): Consideration of aliphatic, alicyclic, linear, alpha, beta‐unsaturated, di‐ and trienals and related alcohols, acids and esters evaluated by JECFA (61st meeting)

An Amphiphilic Resin‐dispersion of Nanoparticles of Platinum (ARP‐Pt): A Highly Active and Recyclable Catalyst for the Aerobic Oxidation of a Variety of Alcohols in Water

An amphiphilic polystyrene-poly(ethylene glycol) (PS-PEG) resin-dispersion of nanoparticles of platinum (ARP-Pt, 4) was developed with a view towards use in catalysis in an aqueous environment under heterogeneous conditions. ARP-Pt 4 was prepared by the reduction of PS-PEG-NH(2)-PtCl(2)(C(2)H(4)) 3, which was generated by mixing PS-PEG-NH(2) 1 and Zeise's salt 2 (K[PtCl(3)(CH(2)CH(2))]), with benzyl alcohol in water (80 degrees C, 12 h). Benzyl alcohol was an essential reducing agent for the preparation of Pt nanoparticles with a narrow size distribution (phi = 5.9+/-0.75 nm) throughout the PS-PEG resin, whereas the reduction of 3 with NaBH(4) gave Pt nanoparticles with broad size distribution (phi = 2-150 nm). ARP-Pt 4 was found to catalyze the aerobic oxidation of a wide variety of alcohols, including non-activated aliphatic and alicyclic alcohols, in water with atmospheric oxygen or air under heterogeneous conditions, and was reused without loss of its catalytic activity, to achieve a highly environmentally-friendly reaction.

Cyclohexane-1,2-dione hydrolase: A new tool to degrade alicyclic compounds

Alicyclic alcohols are naturally occurring compounds which can be degraded by microorganisms via cleavage of the ring C–C bond. Denitrifying Azoarcus sp. strain 22Lin grows on cyclohexane-1,2-diol which serves as electron donor and carbon source. The diol is converted to cyclohexane-1,2-dione followed by hydrolysis to the corresponding semialdehyde and oxidation to adipate. The latter two reactions are catalyzed by the thiamine diphosphate-dependent flavoenzyme cyclohexane-1,2-dione hydrolase, the first α-ketolase known so far. Biochemical and structural properties of this new member of the thiamine diphosphate enzyme family will be presented.

Flavouring Group Evaluation 18, Revision 1 (FGE. 18 Rev1) : Aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols, aromatic tertiary alcohols and their esters from chemical groups 6 and 8

Flavouring Group Evaluation 18, Revision 1 (FGE. 18 Rev1) : Aliphatic, alicyclic and aromatic saturated and unsaturated tertiary alcohols, aromatic tertiary alcohols and their esters from chemical groups 6 and 8

Development of an amphiphilic resin‐dispersion of nanopalladium and nanoplatinum catalysts: Design, preparation, and their use in green organic transformations

An amphiphilic polymer resin-dispersion of nanoparticles of palladium was designed and prepared with a view toward use for catalysis in water. The amphiphilic polystyrene-poly(ethylene glycol) (PS-PEG) resin-dispersion of nanoparticles of palladium exhibited high catalytic performance in the hydrodechlorination of chloroarenes under aqueous conditions. The amphiphilic resin-supported nanopalladium and nanoplatinum particles also catalyzed aerobic oxidation of various alcohols including nonactivated aliphatic and alicyclic alcohols, which is one of the most fundamental and important yet immature processes in organic chemistry, in water under an atmospheric pressure of oxygen gas to form aldehydes, ketones, and carboxylic acids to meet green chemical requirements. Viologen polymer-supported nanopalladium catalyst realized alpha-alkylation of ketones with primary alcohols as the alkylating agents.