Phil Johnson

Dr. Phil Johnson


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2020 in Food and Chemical Toxicology
Verified
Journal Article
Open access
THThomas Holzhauser
Thomas Holzhauser
PJPhil Johnson
Phil Johnson
JHJames P. Hindley
James P. Hindley
GOGavin O'COnnor
Gavin O'COnnor
CCChun-Han Chan
Chun-Han Chan
SFSimon D. Flanagan
Simon D. Flanagan
Food allergy affects up to 6% of Europeans. Allergen identification is important for the risk assessment and management of the inadvertent presence of allergens in foods. The VITAL® initiative for voluntary incidental trace allergen labeling suggests protein reference doses, based on clinical reactivity in food challenge studies, at or below which voluntary labelling is unnecessary. Here, we investigated if current analytical methodology could verify the published VITAL® 2.0 doses, that were available during this analysis, in serving sizes between 5 and 500 g. Available data on published and commercial ELISA, PCR and mass spectrometry methods, especially for the detection of peanuts, soy, hazelnut, wheat, cow's milk and hen's egg were reviewed in detail. Limit of detection, quantitative capability, matrix compatibility, and specificity were assessed. Implications by the recently published VITAL® 3.0 doses were also considered. We conclude that available analytical methods are capable of reasonably robust detection of peanut, soy, hazelnut and wheat allergens for levels at or below the VITAL® 2.0 and also 3.0 doses, with some methods even capable of achieving this in a large 500 g serving size. Cow's milk and hen's egg are more problematic, largely due to matrix/processing incompatibility. An unmet need remains for harmonized reporting units, available reference materials, and method ring-trials to enable validation and the provision of comparable measurement results.

18 February 2020 in Molecular Nutrition & Food Research
Verified
Journal Article
Closed access
PDF file
LPLee K. Palmer
Lee K. Palmer
JMJustin T. Marsh
Justin T. Marsh
MLMei Lu
Mei Lu
RGRichard E. Goodman
Richard E. Goodman
MZMichael G. Zeece
Michael G. Zeece
PJPhil Johnson
Phil Johnson

1 May 2021 in Food and Chemical Toxicology
Verified
Journal Article
Open access
SYSezin Yigit
Sezin Yigit
NHNadia S. Hallaj
Nadia S. Hallaj
JSJames L. Sugarman
James L. Sugarman
LCLester C. Chong
Lester C. Chong
SRSamantha E. Roman
Samantha E. Roman
ABAdam M. Behrens
Adam M. Behrens
Recent studies have demonstrated silk fibroin protein's (SF) ability to extend the shelf life of foods by mitigating the hallmarks of spoilage, namely oxidation and dehydration. Due to the potential for this protein to become more widespread, its safety was evaluated comprehensively. First, a bacterial reverse mutation test (Ames test) was conducted in five bacterial strains. Second, an in vivo erythrocyte test was conducted with Sprague Dawley rats at doses up to 1,000mg/kg-bw/day. Third, a range-finder study was conducted with Sprague Dawley rats at the highest consumption amount given solubility and oral gavage volume constrains (500mg/kg-bw/day). Fourth, a 28-day sub-chronic study in Sprague Dawley rats was conducted with the high dose set at 500mg/kg-bw/day, as limited by solubility of the protein in a single-gavage per-day study. Fifth, an in vitro pepsin digestion assay was performed to assess the potential for protein allergenicity. Sixth, allergenic potential was further assessed using liquid chromatography-mass spectroscopy for detection of allergenic insect proteins. Seventh, the SF protein sequences were subjected to bioinformatic analyses. Together, these studies raise no mutagenic, genotoxic, toxicological, or allergenic concerns with the oral consumption of silk fibroin.

1 May 2020 in Food Chemistry
Verified
Journal Article
Closed access
JMJustin T. Marsh
Justin T. Marsh
SJShyamali Jayasena
Shyamali Jayasena
FGFerdelie Gaskin
Ferdelie Gaskin
JBJoseph L. Baumert
Joseph L. Baumert
PJPhil Johnson
Phil Johnson

26 May 2021 in Journal of Agricultural and Food Chemistry
Verified
Journal Article
Closed access
DADanijela Apostolovic
Danijela Apostolovic
JMJustin T. Marsh
Justin T. Marsh
JBJoe Baumert
Joe Baumert
STSteve Taylor
Steve Taylor
AWAdrie Westphal
Adrie Westphal
SKStef Koppelman
Stef Koppelman