TY  - JOUR
AU  - Krishna de Guzman, Maria
AU  - Stanić-Vučinić, Dragana
AU  - Gligorijević, Nikola
AU  - Wimmer, Lukas
AU  - Gasparyan, Manvel
AU  - Lujić, Tamara
AU  - Vasović, Tamara
AU  - Dailey, Lea Ann
AU  - Van Haute, Sam
AU  - Ćirković-Veličković, Tanja
PY  - 2023
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/6320
AB  - Human ingestion of microplastics (MPs) is common and inevitable due to the widespread contamination of food items, but implications on the gastric digestion of food proteins are still unknown. In this study, the interactions between pepsin and polystyrene (PS) MPs were evaluated by investigating enzyme activity and conformation in a simulated human gastric environment in the presence or absence of PS MPs. The impact on food digestion was also assessed by monitoring the kinetics of protein hydrolysis through static in vitro gastric digestion of cow's milk contaminated with PS. The binding of pepsin to PS showed that the surface chemistry of MPs dictates binding affinity. The key contributor to pepsin adsorption seems to be π−π interactions between the aromatic residues and the PS phenyl rings. During quick exposure (10 min) of pepsin to increasing concentrations (222, 2219, 22188 particles/mL) of 10 μm PS (PS10) and 100 μm PS (PS100), total enzymatic activities were not affected remarkably. However, upon prolonged exposure at 1 and 2 h, preferential binding of pepsin to the small, low zeta-potential PS caused structural changes in the protein which led to a significant reduction of its activity. Digestion of cow's milk mixed with PS10 resulted in transient accumulation of larger peptides (10–35 kDa) and reduced bioavailability of short peptides (2–9 kDa) in the gastric phase. This, however, was only observed at extremely high PS10 concentration (0.3 mg/mL or 5.46E+05 particles/mL). The digestion of milk peptides, bound preferentially over pepsin within the hard corona on the PS10 surface, was delayed up to 15 min in comparison to bulk protein digestion. Intact caseins, otherwise rapidly digested, remained bound to PS10 in the hard corona for up to 15 min. This work presents valuable insights regarding the interaction of MPs, food proteins, and pepsin, and their dynamics during gastric digestion.
PB  - Elsevier
T2  - Environmental Pollution
T1  - Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion
VL  - 335
SP  - 122282
DO  - 10.1016/j.envpol.2023.122282
ER  - 

@article{
author = "Krishna de Guzman, Maria and Stanić-Vučinić, Dragana and Gligorijević, Nikola and Wimmer, Lukas and Gasparyan, Manvel and Lujić, Tamara and Vasović, Tamara and Dailey, Lea Ann and Van Haute, Sam and Ćirković-Veličković, Tanja",
year = "2023",
abstract = "Human ingestion of microplastics (MPs) is common and inevitable due to the widespread contamination of food items, but implications on the gastric digestion of food proteins are still unknown. In this study, the interactions between pepsin and polystyrene (PS) MPs were evaluated by investigating enzyme activity and conformation in a simulated human gastric environment in the presence or absence of PS MPs. The impact on food digestion was also assessed by monitoring the kinetics of protein hydrolysis through static in vitro gastric digestion of cow's milk contaminated with PS. The binding of pepsin to PS showed that the surface chemistry of MPs dictates binding affinity. The key contributor to pepsin adsorption seems to be π−π interactions between the aromatic residues and the PS phenyl rings. During quick exposure (10 min) of pepsin to increasing concentrations (222, 2219, 22188 particles/mL) of 10 μm PS (PS10) and 100 μm PS (PS100), total enzymatic activities were not affected remarkably. However, upon prolonged exposure at 1 and 2 h, preferential binding of pepsin to the small, low zeta-potential PS caused structural changes in the protein which led to a significant reduction of its activity. Digestion of cow's milk mixed with PS10 resulted in transient accumulation of larger peptides (10–35 kDa) and reduced bioavailability of short peptides (2–9 kDa) in the gastric phase. This, however, was only observed at extremely high PS10 concentration (0.3 mg/mL or 5.46E+05 particles/mL). The digestion of milk peptides, bound preferentially over pepsin within the hard corona on the PS10 surface, was delayed up to 15 min in comparison to bulk protein digestion. Intact caseins, otherwise rapidly digested, remained bound to PS10 in the hard corona for up to 15 min. This work presents valuable insights regarding the interaction of MPs, food proteins, and pepsin, and their dynamics during gastric digestion.",
publisher = "Elsevier",
journal = "Environmental Pollution",
title = "Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion",
volume = "335",
pages = "122282",
doi = "10.1016/j.envpol.2023.122282"
}

Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution
Elsevier., 335, 122282.
https://doi.org/10.1016/j.envpol.2023.122282

Krishna de Guzman M, Stanić-Vučinić D, Gligorijević N, Wimmer L, Gasparyan M, Lujić T, Vasović T, Dailey LA, Van Haute S, Ćirković-Veličković T. Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution. 2023;335:122282.
doi:10.1016/j.envpol.2023.122282 .

Krishna de Guzman, Maria, Stanić-Vučinić, Dragana, Gligorijević, Nikola, Wimmer, Lukas, Gasparyan, Manvel, Lujić, Tamara, Vasović, Tamara, Dailey, Lea Ann, Van Haute, Sam, Ćirković-Veličković, Tanja, "Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion" in Environmental Pollution, 335 (2023):122282,
https://doi.org/10.1016/j.envpol.2023.122282 . .

TY  - DATA
AU  - de Guzman, Maria Krishna
AU  - Stanić-Vučinić, Dragana
AU  - Gligorijević, Nikola
AU  - Wimmer, Lukas
AU  - Gasparyan, Manvel
AU  - Lujić, Tamara
AU  - Vasović, Tamara
AU  - Dailey, Lea Ann
AU  - Van Haute, Sam
AU  - Ćirković-Veličković, Tanja
PY  - 2023
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/6463
AB  - The analysis of structural changes of pepsin in the presence of polystyrene microplastic of 10 and 100 µm in size in simulated gastric fluid. Data obtained from J-815 CD spectropolarimeter, and further analyzed by Origin and Excel software.
T2  - Environmental Pollution
T1  - Research data for: Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution Elsevier., 335, 122282. https://doi.org/10.1016/j.envpol.2023.122282
UR  - https://hdl.handle.net/21.15107/rcub_cherry_6463
ER  - 

@misc{
author = "de Guzman, Maria Krishna and Stanić-Vučinić, Dragana and Gligorijević, Nikola and Wimmer, Lukas and Gasparyan, Manvel and Lujić, Tamara and Vasović, Tamara and Dailey, Lea Ann and Van Haute, Sam and Ćirković-Veličković, Tanja",
year = "2023",
abstract = "The analysis of structural changes of pepsin in the presence of polystyrene microplastic of 10 and 100 µm in size in simulated gastric fluid. Data obtained from J-815 CD spectropolarimeter, and further analyzed by Origin and Excel software.",
journal = "Environmental Pollution",
title = "Research data for: Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution Elsevier., 335, 122282. https://doi.org/10.1016/j.envpol.2023.122282",
url = "https://hdl.handle.net/21.15107/rcub_cherry_6463"
}

de Guzman, M. K., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Research data for: Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution Elsevier., 335, 122282. https://doi.org/10.1016/j.envpol.2023.122282. in Environmental Pollution.
https://hdl.handle.net/21.15107/rcub_cherry_6463

de Guzman MK, Stanić-Vučinić D, Gligorijević N, Wimmer L, Gasparyan M, Lujić T, Vasović T, Dailey LA, Van Haute S, Ćirković-Veličković T. Research data for: Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution Elsevier., 335, 122282. https://doi.org/10.1016/j.envpol.2023.122282. in Environmental Pollution. 2023;.
https://hdl.handle.net/21.15107/rcub_cherry_6463 .

de Guzman, Maria Krishna, Stanić-Vučinić, Dragana, Gligorijević, Nikola, Wimmer, Lukas, Gasparyan, Manvel, Lujić, Tamara, Vasović, Tamara, Dailey, Lea Ann, Van Haute, Sam, Ćirković-Veličković, Tanja, "Research data for: Krishna de Guzman, M., Stanić-Vučinić, D., Gligorijević, N., Wimmer, L., Gasparyan, M., Lujić, T., Vasović, T., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2023). Small polystyrene microplastics interfere with the breakdown of milk proteins during static in vitro simulated human gastric digestion. in Environmental Pollution Elsevier., 335, 122282. https://doi.org/10.1016/j.envpol.2023.122282" in Environmental Pollution (2023),
https://hdl.handle.net/21.15107/rcub_cherry_6463 .

TY  - CONF
AU  - de Guzman, Maria Krishna
AU  - Wimmer, Lukas
AU  - Dailey, Lea Ann
AU  - Van Haute, Sam
AU  - Ćirković-Veličković, Tanja
PY  - 2022
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5908
AB  - The prevalence of microplastics (MP) pollution in
different zones of the environment has been
established by several studies [1]. Due to its
widespread presence, MP have found its way into
food items. Fish, shellfish, water, milk, salt, and
sugar are just some examples of the food we
commonly consume that are contaminated with MP
[2]. Human ingestion of MP is already well-established
but there is limited data regarding how
MP affect human gastric digestion of food
components, especially proteins.
In this study, we investigated the effects of
polystyrene (PS) MP on pepsin, the major protease
in human gastric digestion. Pepsin activity was
tested during exposure to two different sizes -10 μm
(PS10) and 100 μm (PS100), and three different
quantities- low count (142 particles), moderate
count (1420 particles), and high count
(14200 particles), of PS using haemoglobin as
substrate. Results showed that exposure to PS100
has no effect on enzyme activity. However,
exposure to high count PS10 considerably reduced
pepsin activity from 2957 ± 310 U/mg to 1674 ± 270
U/mg.
To test the effect on food digestion, high count
PS10 was added to a sample of commercially
available liquid bovine milk (defatted). In this case,
the static in vitro simulation of gastric digestion was
followed to mimic human digestion of food [3].
Milk digesta at different time points (5, 10, 15, 20,
30, 60, 90, 120 minutes) were obtained to monitor
the progress of protein degradation.
SDS-PAGE showed no difference in the peptide
bands from 30-120 minutes. However, bands
corresponding to caseins were not observed at 5
minutes when PS10 was present. Additionally,
14 kDa fragments were not observed at 10-20
minutes.
Washing of the PS particles followed by SDSPAGE
revealed a faint pepsin band from all time
points. At 5 and 10 minutes, faint peptide bands
>10kDa were also observed. These suggest that
pepsin and some milk peptides were adsorbed on
the surface of PS10. Zeta potential analysis of PS
revealed a slightly negative surface charge which
could explain the adsorption and disappearance of
peptide bands. This adsorption of pepsin on PS did
not seem to affect its overall protease activity.
However, the interaction of milk peptides with PS
may reduce the nutrients human could acquire from
milk.
Acknowledgements
This study was supported by Ghent University
Global Campus; Special Research Fund (BOF) of
Ghent University (grant number 01N01718) and
IMPTOX European Union’s Horizon 2020 research
and innovation program (grant number 965173).
References
[1] S. Sharma, S. Basu, N. P. Shetti, M. N. Nadagouda, T.
M. Aminabhavi (2021) Chem. Eng. J., 408, 127317.
[2] K. D. Cox, G. A. Covernton, H. L. Davies, J. F. Dower,
F. Juanes, S. E. Dudas (2019) Environ. Sci. Technol.,
53(12), 7068–7074.
[3] A. Brodkorb et al. (2019) Nat. Protoc., 14(4), 991–
1014.
PB  - University of Ljubljana Press
C3  - Book of Abstracts of the 22nd European Meeting on Environmental Chemistry, Ljubljana, Slovenia, 5-8 December 2022
T1  - Implications of Polystyrene Microplastics on the Gastric Digestion of Bovine Milk
SP  - 124
EP  - 124
UR  - https://hdl.handle.net/21.15107/rcub_cherry_5908
ER  - 

@conference{
author = "de Guzman, Maria Krishna and Wimmer, Lukas and Dailey, Lea Ann and Van Haute, Sam and Ćirković-Veličković, Tanja",
year = "2022",
abstract = "The prevalence of microplastics (MP) pollution in
different zones of the environment has been
established by several studies [1]. Due to its
widespread presence, MP have found its way into
food items. Fish, shellfish, water, milk, salt, and
sugar are just some examples of the food we
commonly consume that are contaminated with MP
[2]. Human ingestion of MP is already well-established
but there is limited data regarding how
MP affect human gastric digestion of food
components, especially proteins.
In this study, we investigated the effects of
polystyrene (PS) MP on pepsin, the major protease
in human gastric digestion. Pepsin activity was
tested during exposure to two different sizes -10 μm
(PS10) and 100 μm (PS100), and three different
quantities- low count (142 particles), moderate
count (1420 particles), and high count
(14200 particles), of PS using haemoglobin as
substrate. Results showed that exposure to PS100
has no effect on enzyme activity. However,
exposure to high count PS10 considerably reduced
pepsin activity from 2957 ± 310 U/mg to 1674 ± 270
U/mg.
To test the effect on food digestion, high count
PS10 was added to a sample of commercially
available liquid bovine milk (defatted). In this case,
the static in vitro simulation of gastric digestion was
followed to mimic human digestion of food [3].
Milk digesta at different time points (5, 10, 15, 20,
30, 60, 90, 120 minutes) were obtained to monitor
the progress of protein degradation.
SDS-PAGE showed no difference in the peptide
bands from 30-120 minutes. However, bands
corresponding to caseins were not observed at 5
minutes when PS10 was present. Additionally,
14 kDa fragments were not observed at 10-20
minutes.
Washing of the PS particles followed by SDSPAGE
revealed a faint pepsin band from all time
points. At 5 and 10 minutes, faint peptide bands
>10kDa were also observed. These suggest that
pepsin and some milk peptides were adsorbed on
the surface of PS10. Zeta potential analysis of PS
revealed a slightly negative surface charge which
could explain the adsorption and disappearance of
peptide bands. This adsorption of pepsin on PS did
not seem to affect its overall protease activity.
However, the interaction of milk peptides with PS
may reduce the nutrients human could acquire from
milk.
Acknowledgements
This study was supported by Ghent University
Global Campus; Special Research Fund (BOF) of
Ghent University (grant number 01N01718) and
IMPTOX European Union’s Horizon 2020 research
and innovation program (grant number 965173).
References
[1] S. Sharma, S. Basu, N. P. Shetti, M. N. Nadagouda, T.
M. Aminabhavi (2021) Chem. Eng. J., 408, 127317.
[2] K. D. Cox, G. A. Covernton, H. L. Davies, J. F. Dower,
F. Juanes, S. E. Dudas (2019) Environ. Sci. Technol.,
53(12), 7068–7074.
[3] A. Brodkorb et al. (2019) Nat. Protoc., 14(4), 991–
1014.",
publisher = "University of Ljubljana Press",
journal = "Book of Abstracts of the 22nd European Meeting on Environmental Chemistry, Ljubljana, Slovenia, 5-8 December 2022",
title = "Implications of Polystyrene Microplastics on the Gastric Digestion of Bovine Milk",
pages = "124-124",
url = "https://hdl.handle.net/21.15107/rcub_cherry_5908"
}

de Guzman, M. K., Wimmer, L., Dailey, L. A., Van Haute, S.,& Ćirković-Veličković, T.. (2022). Implications of Polystyrene Microplastics on the Gastric Digestion of Bovine Milk. in Book of Abstracts of the 22nd European Meeting on Environmental Chemistry, Ljubljana, Slovenia, 5-8 December 2022
University of Ljubljana Press., 124-124.
https://hdl.handle.net/21.15107/rcub_cherry_5908

de Guzman MK, Wimmer L, Dailey LA, Van Haute S, Ćirković-Veličković T. Implications of Polystyrene Microplastics on the Gastric Digestion of Bovine Milk. in Book of Abstracts of the 22nd European Meeting on Environmental Chemistry, Ljubljana, Slovenia, 5-8 December 2022. 2022;:124-124.
https://hdl.handle.net/21.15107/rcub_cherry_5908 .

de Guzman, Maria Krishna, Wimmer, Lukas, Dailey, Lea Ann, Van Haute, Sam, Ćirković-Veličković, Tanja, "Implications of Polystyrene Microplastics on the Gastric Digestion of Bovine Milk" in Book of Abstracts of the 22nd European Meeting on Environmental Chemistry, Ljubljana, Slovenia, 5-8 December 2022 (2022):124-124,
https://hdl.handle.net/21.15107/rcub_cherry_5908 .