Papers by Sabina Passamonti
EUT Edizioni Università di Trieste eBooks, 2014
Biochemical and Biophysical Research Communications, Jun 1, 1998
In the primary structure of bilitranslocase, currently under study in our laboratory, an aminoaci... more In the primary structure of bilitranslocase, currently under study in our laboratory, an aminoacid motif was identified and found to be conserved in a number of alpha-phycocyanines, ancient biliproteins present in cyanobacteria. To test the possibility that such a motif could be at least part of the binding site for bilirubin, epitope-specific antibodies were raised. The target corresponds to the sequence 65-75 of bilitranslocase and covers the central portion of the motif identified. The antibodies were shown: 1) to inhibit the electrogenic BSP transport by plasmamembrane vesicles; 2) to react with purified bilitranslocase; and 3) to identify only one protein band with electrophoretic mobility identical to bilitranslocase in Western blots of solubilised plasmamembrane vesicles. The presence of either bilirubin or nicotinate during pre-incubation with the antibodies decreases concentration-wise the inhibition kinetics. From these experiments a dissociation constant of 2.2 +/- 0.3 and 11.3 +/- 1.3 nM for bilirubin-bilitranslocase and nicotinate-bilitranslocase complexes were calculated.
EFSA Journal, May 1, 2023
The Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinio... more The Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion re-evaluating the safety of xanthan gum (E 415) as food additive. Following the conceptual framework for the risk assessment of certain food additives re-evaluated under Commission Regulation (EU) No 257/2010, the Panel considered that adequate exposure and toxicity data were available. Based on the reported use levels, a refined exposure of up to 64 mg/kg bw per day in children for the general population, 38 mg/kg bw per day for children consumers only of food supplements at the high level exposure and 115 mg/kg bw per day for infants consuming foods for special medical purposes and special formulae (FSMPs), were estimated. Xanthan gum (E 415) is unlikely to be absorbed intact and is expected to be fermented by intestinal microbiota. No adverse effects were reported at the highest doses tested in chronic and carcinogenicity studies and there is no concern with respect to the genotoxicity. Repeated oral intake by adults of xanthan gum up to 214 mg/kg bw per day for ten days was well tolerated, but some individuals experienced abdominal discomfort, an undesirable but not adverse effect. The Panel concluded that there is no need for a numerical ADI for xanthan gum (E 415), and that there is no safety concern for the general population at the refined exposure assessment of xanthan gum (E 415) as food additive. Considering the outcome of clinical studies and post-marketing surveillance, the Panel concluded that there is no safety concern from the use of xanthan gum (E 415) in FSMPs for infants and young children at concentrations reported by the food industry. The current re-evaluation of xanthan gum (E 415) as a food additive is not considered to be applicable for infants under the age of 12 weeks.
EFSA Journal, Feb 1, 2022
Abstract The EFSA Panel on Food Additive and Flavourings (FAF) assessed the safety of glucosylate... more Abstract The EFSA Panel on Food Additive and Flavourings (FAF) assessed the safety of glucosylated steviol glycosides proposed for use as a new food additive in different food categories. Glucosylated steviol glycosides consist of a mixture of glucosylated steviol glycosides, containing 1–20 additional glucose units bound to the parent steviol glycosides. Glucosylated steviol glycosides consist of not less than 95% (on dry, dextrin‐free, basis) of total steviol glycosides, comprised of glucosylated and parent steviol glycosides. Glucosylated steviol glycosides are produced via enzymatic bioconversion using cyclomaltodextrin glucanotransferase (CGTase) (EC 2.4.1.19), derived from a non‐genetically modified strain of Anoxybacillus caldiproteolyticus, that catalyses the transfer of glucose from starch to steviol glycosides mixtures isolated from the dried leaves of Stevia Rebaudiana. The Panel considered that the metabolism of glucosylated steviol glycosides is sufficiently similar to the already authorised steviol glycosides, and thus, the toxicological data previously assessed by the ANS Panel for steviol glycosides (E 960) were considered to support their safety as food additive. The existing acceptable daily intake (ADI) for steviol glycosides (E 960) of 4 mg/kg body weight (bw) per day expressed as steviol can also be applied to glucosylated steviol glycosides. The Panel concluded that there is no safety concern for the use of glucosylated steviol glycosides as a new food additive at the proposed use and use levels. The Panel recommended some modifications to the specifications proposed by the applicant for glucosylated steviol glycosides with respect to the assay, the definition of the proposed new food additive and the proposed maximum limits for arsenic.
EFSA Journal, Apr 1, 2020
The EFSA Panel on Food Additives and Flavourings (FAF) provides a scientific opinion on the safet... more The EFSA Panel on Food Additives and Flavourings (FAF) provides a scientific opinion on the safety of the proposed amendment of the specifications for steviol glycosides (E 960) as a food additive, in particular to expand the list of steviol glycosides to 60 steviol glycosides identified in the leaves of Stevia Rebaudiana Bertoni. With the existing specifications, the food additive must be comprised of not less than 95% of the 11 named steviol glycosides. The proposed change is to include all 60 steviol glycosides in the same limit value of 95% and this would allow the presence of up to 5% of impurities. FAF Panel considered that all steviol glycosides share the same metabolic fate, and therefore, the safety of 60 identified steviol glycosides can be based on read-across from toxicological data previously evaluated by EFSA and the acceptable daily intake (ADI) of 4 mg/kg body weight (bw) per day will apply to all those steviol glycosides. However, according to the proposed change in specifications, there remains a small but not insignificant fraction of the additive that would be undefined and therefore cannot be evaluated by the Panel. The Panel concluded that the inclusion of the 60 steviol glycosides in the proposed specifications for steviol glycoside (E960) would not be of safety concern. However, the Panel cannot conclude on the safety of the proposed amendment to the specifications of steviol glycosides (E 960) as food additive if the purity assay value of not less than 95% for the total content of steviol glycosides is maintained.
Frontiers in Bioengineering and Biotechnology, Sep 12, 2018
Stimuli-responsive hydrogel matrices are inspiring manifold applications in controlled delivery o... more Stimuli-responsive hydrogel matrices are inspiring manifold applications in controlled delivery of bioactive compounds. Elastin-derived polypeptides form hydrogel matrices that may release bioactive moieties as a function of local increase of active elastases, as it would occur in several processes like inflammation. In view of the development of a patch for healing wounds, recombinant elastin-based polypeptides were combined with a proteolysis-resistant scaffold, made of electrospun poly-L-lactic acid (PLLA) fibers. The results of this study demonstrated the compatibility of these two components. An efficient procedure to obtain a composite material retaining the main features of each component was established. The release of the elastin moiety was monitored by means of a simple protocol. Our data showed that electrospun PLLA can form a composite with fusion proteins bound to elastin-derived polypeptides. Therefore, our approach allows designing a therapeutic agent delivery platform to realize devices capable of responding and interacting with biological systems at the molecular level.
EFSA Journal, Feb 1, 2022
The EFSA Panel on Food Additives and Flavourings was requested to evaluate 55 flavouring substanc... more The EFSA Panel on Food Additives and Flavourings was requested to evaluate 55 flavouring substances assigned to the Flavouring Group Evaluation 07 (FGE.07), using the Procedure as outlined in the Commission Regulation (EC) No 1565/2000. Fifty-three substances have already been considered in FGE.07 and its revisions. This revision 6 includes two additional substances which have been cleared with respect to genotoxicity in FGE.201Rev2 (4-methyl-3-hepten-5-one [FL-no: 07.261]) and FGE.204Rev1 (non-2-en-4-one, [FL-no: 07.187]). The substances were evaluated through a stepwise approach that integrates information on the structure-activity relationships, intake from current uses, toxicological threshold of concern (TTC) and available data on metabolism and toxicity. The Panel concluded that none of the 55 substances gives rise to safety concerns at their levels of dietary intake, when estimated on the basis of the 'Maximised Survey-derived Daily Intake' (MSDI) approach. Besides the safety assessment of the flavouring substances, the specifications for the materials of commerce have also been considered and found adequate. Normal and maximum use levels were available for all flavouring substances. For 52 substances, including the newly included substances [FL-no: 07.187 and 07.261], their 'modified Theoretical Added Maximum Daily Intakes' (mTAMDIs) estimates were above the TTC for their structural classes (I and II). Therefore, for these 52 flavouring substances, more detailed data on uses and use levels should be provided to finalise their safety evaluations.
EFSA Journal, Feb 1, 2022
Scientific Opinion on Flavouring Group Evaluation 63, Revision 4 (FGE.63Rev4): consideration of a... more Scientific Opinion on Flavouring Group Evaluation 63, Revision 4 (FGE.63Rev4): consideration of aliphatic secondary saturated and unsaturated alcohols, ketones and related esters evaluated by JECFA (59th and 69th meetings) structurally related to flavouring substances evaluated by EFSA in FGE.07Rev6 EFSA Panel on Food Additives and Flavourings (FAF),
EFSA Journal, Aug 1, 2020
EFSA Journal, Aug 1, 2022
EFSA Journal, Nov 1, 2021
Opinion on the re-evaluation of mono-and diglycerides of fatty acids (E 471) as food additive in ... more Opinion on the re-evaluation of mono-and diglycerides of fatty acids (E 471) as food additive in foods for infants below 16 weeks of age and follow-up of their re-evaluation as food additives for uses in foods for all population groups EFSA Panel on Food Additives and Flavourings (FAF),
Journal of Biotechnology, Aug 1, 2017
Elastin is a fibrous protein that confers elasticity to tissues such as skin, arteries and lung. ... more Elastin is a fibrous protein that confers elasticity to tissues such as skin, arteries and lung. It is extensively crosslinked, highly hydrophobic and insoluble. Nevertheless, elastin can be hydrolysed by bacterial proteases in infectious diseases, resulting in more or less severe tissue damage. Thus, development of substrates able to reliably and specifically detect pathogen-secreted elastolytic activity is needed to improve the in vitro evaluation of the injury that bacterial proteases may provoke. In this work, two human biomimetic elastin polypeptides, HELP and HELP1, as well as the matrices derived from HELP, have been probed as substrates for elastolytic activity detection. Thirty strains of Pseudomonas aeruginosa isolated from cystic fibrosis patients were analyzed in parallel with standard substrates, to detect proteolytic and elastolytic activity. Results point to the HELP-based 3D matrix as an interesting biomimetic model of elastin to assess bacterial elastolytic activity in vitro. Moreover, this model substrate enables to further elucidate the mechanism underlying elastin degradation at molecular level, as well as to develop biomimetic material-based devices responsive to external stimuli.
EFSA Journal, Jul 1, 2023
EFSA Journal, Jul 1, 2023
EFSA Journal, Apr 1, 2023
EFSA Journal, Apr 1, 2023
EFSA Journal, Feb 1, 2023
EFSA Journal, Dec 1, 2022
Following a request from the European Commission, EFSA developed a new scientific guidance to ass... more Following a request from the European Commission, EFSA developed a new scientific guidance to assist applicants in the preparation of applications for the authorisation of flavourings to be used in or on foods. This guidance applies to applications for a new authorisation as well as for a modification of an existing authorisation of a food flavouring, submitted under Regulation (EC) No 1331/2008. It defines the scientific data required for the evaluation of those food flavourings for which an evaluation and approval is required according to Article 9 of Regulation (EC) No 1334/2008. This applies to flavouring substances, flavouring preparations, thermal process flavourings, flavour precursors, other flavourings and source materials, as defined in Article 3 of Regulation (EC) No 1334/2008. Information to be provided in all applications relates to: (a) the characterisation of the food flavouring, including the description of its identity, manufacturing process, chemical composition, specifications, stability and reaction and fate in foods; (b) the proposed uses and use levels and the assessment of the dietary exposure and (c) the safety data, including information on the genotoxic potential of the food flavouring, toxicological data other than genotoxicity and information on the safety for the environment. For the toxicological studies, a tiered approach is applied, for which the testing requirements, key issues and triggers are described. Applicants should generate the data requested in each section to support the safety assessment of the food flavouring. Based on the submitted data, EFSA will assess the safety of the food flavouring and conclude whether or not it presents risks to human health and to the environment, if applicable, under the proposed conditions of use.
EFSA Journal, Jun 1, 2022
Glycerol (E 422) was re-evaluated in 2017 by the former EFSA Panel on Food Additives and Nutrient... more Glycerol (E 422) was re-evaluated in 2017 by the former EFSA Panel on Food Additives and Nutrient sources added to Food (ANS). As a follow-up to that assessment, in this opinion, the Panel on Food Additives and Flavourings (FAF) addresses the data gaps identified to support an amendment of the EU specifications for E 422 in Commission Regulation (EU) No 231/2012. The Panel performed a risk assessment of undesirable impurities present in E 422. The Panel concluded that the maximum limits in the EU specifications for the four toxic elements (arsenic, lead, mercury and cadmium) should be lowered based on actual levels in the commercial food additive E 422. The Panel recommended setting a numerical limit value for acrolein in the specifications for E 422. The potential exposure to free 3-monochloropropanediol at the maximum limit of 0.1 mg/kg, as laid out in the specifications for E 422, does not give rise to a health concern. The Panel recommended to consider modifying the definition of E 422 in Commission Regulation (EU) No 231/2012 indicating that E 422 is obtained only from vegetable oils and fats and undergoes purification processes that involve distillation, and other clean up steps to obtain refined glycerol. Overall, the Panel concluded that the technical data provided support an amendment of the specifications for glycerol (E 422).
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Papers by Sabina Passamonti