IONIZING RADIATION: a tool to control environmental ...c2tn.tecnico.ulisboa.pt/images/1st_c2tn_workshop/... · ionizing radiation in several matrices, and identify the radioresistance

IST – C2TN 18-12-2013 1

IONIZING RADIATION:

a tool to control

environmental microbiota

towards public health

safety

1st Workshop C2TN: RADIATION FOR SCIENCE AND SOCIETY 6.12.2017

C2TN: Sandra Cabo Verde,

Pedro Santos, Fernanda Margaça

Joana Madureira, Andreia Severino, Catarina Palma,

Maria Inês Santos, Maria Inês Elias, Ana Sofia Dias

IPB: Amílcar António, Isabel C.F.R. Ferreira

FCUL: Manuela Carolino

You’ve got to respect microbes. Not because “they are the only culture some people have,” as the

comedian Steven Wright puts it. Nai et al. Fungal Biol Biotechnol (2016) 3:5

DOI 10.1186/s40694-016-0023-9

Microorganisms are part of

crucial advances in our

modern Society:

• Human health and welfare,

• Industry,

• Environment.


The Microbiome


The Microbiome


Out of control


The Tool

Ionizing

Radiation


Our Research

Study the microbial inactivation [bacteria,

filamentous fungi and enteric virus] by

ionizing radiation in several matrices, and

identify the radioresistance and

radiosensitizing factors.

AIM

• Estimative of the required radiation

doses to attain a desired microbicidal

efficiency.

• Proposal of mechanistic models for

microbial inactivation by ionizing

radiation.

OUTPUTS

OUTCOMES

Development of efficient processes for

the mitigation of emergent risks for public

health and environment, namely microbial

outbreaks, foodborne and waterborne

diseases.

SOCIETAL CHALLENGE

• Prevention of infectious diseases;

• Food Safety, Sustainable Agro-industry;

• Environmental protection, Sustainable

management of natural resources.

IMPACT

Food Safety


Project AIEA/ CRP D6-RC-1163.2 - Development of Irradiated Foods for Immuno-Compromised Patients and other Potential Target

Groups (2011-2015)

0

1

2

3

4

5

0 7 14

Log

CFU

/g

Storage time (days)

0 kGy 1.3 kGy 3.2 kGy 5.7 kGy

Total mesophilic counts for non-irradiated and irradiated cherry

tomatoes during storage time (n=6; α = 0.05).

0

1

2

3

4

5

6

7

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6

Log

CFU

/g

Dose (kGy)

Salmonella Typhimurium Escherichia coli Sthapylococcus aureus

Comparision of the sensitivities of Salmonella Typhimurium, Escherichia coli

and Sthaphylococcus aureus to gamma radiation in cherry tomatoes.

Microorganism D-10 value (kGy) Log-reduction after 3 kGy

Salmonella Typhimurium ATCC 14028

0.30 ± 0.01 kGy 10

Escherichia coli ATCC 8739

0.71 ± 0.04 kGy 4

Staphylococcus aureus ATCC 6538

0.45 ± 0.02 kGy 7

A decontamination dose of 3 kGy:

• 2 log reduction of natural microbiota

• 4 - 10 log-reduction in survival of potential pathogenic

bacteria.

Increase on antioxidant content of irradiated cherry tomatoes.

Organoleptic properties are preserved with irradiation treatment. http://dx.doi.org/10.1080/15287394.2013.757256

http://dx.doi.org/10.3233/JBR130050.

http://dx.doi.org/10.1016/j.ifset.2016.05.008.

Food Safety


AROMAP - PRODER nº 53515/2014 - Processamento de

plantas aromáticas condimentares (2014-2016) –

Promotor: “Mais Ervas”

PO Regional de Lisboa 2007-2013, Inovar para

Competir – Avaliação da radiação gama como

tratamento alternativo para preservação de manteigas.

Promotor: “Tété II- Produtos Lácteos, Lda. (2015)

Gamma radiation inactivation curve for the microbial population of Peppermint.

0.01.02.03.04.05.06.0

0 2 4 6 8 10 12

Log

CFU

/g

Dose (kGy)

Peppermint

0.01.02.03.04.05.06.0

0 2 4 6 8 10 12Lo

g C

FU/g

Dose (kGy)

Peppermint

Preservation treatment doses 5-10 kGy for dried aromatic

and medicinal plants:

- Decontamination of microbial population (>2 log)

- Preservation of biochemical profile

- Preservation of antimicrobial properties

http://dx.doi.org/10.3390/molecules2203034;

http://dx.doi.org/10.1016/j.indcrop.2017.01.007;

http://dx.doi.org/10.1016/j.lwt.2016.07.027

http://dx.doi.org/10.1016/j.lwt.2016.04.004.

Irradiation of cream no effect on shelf-

life extension of butter.

http://dx.doi.org/ 10.1016/j.idairyj.2017.03.003.

Total counts for (A) mesophilic bacterial population and (B) filamentous fungi

population of sheep control butter ( ■) and butter produced with irradiated cream (●)

during storage.

Food Safety


IAEA project 19220 - Fostering e-beam food irradiation:

Modelling and Validation (2015-2019)

• Protocols detailing irradiation by e-beam of specific categories of food: microbiological and bioactivity assessments.

• Case studies on pilot scale testing and full scale demonstration of e-beam irradiation of food in collaboration with food industry.

Coming soon…

Author’s Country: Australia Belgium Canada England France Ireland New Zeeland Poland Portugal Romania South Korea USA …

E-Beam Food Irradiation


Environmental Protection

Project AIEA/ CRP 1539 – Radiation Treatment of Wastewater for Reuse with Particular Focus on Wastewaters Containing Organic

Pollutants (2011-2015)

Gamma radiation treated cork boiling wastewater

indicated to be toxic for prokaryotic and eukaryotic cells. http://dx.doi.org/10.1016/j.chemosphere.2016.11.064.

Approach to associate the metabolic capacities of CORK

WASTEWATER microbial consortium along with a radiolytic

process, in order to promote the recalcitrant compounds

degradation.

J. Adv. Oxid. Technol. Vol. 19, No. 1, 2016

BATCH BIODEGRADATION EXPERIMENTS

High phenolic content Recalcitrant pollutants

Characterization of the radiolytic degradation of phenolic

compounds and proposal of their fragmentation pathway. J. Madureira et al., Chemical Engineering Journal, submitted



IAEA Project 17474 - Survival and inactivation patterns of viral threat agents in the environment: assessment of ionizing radiation as

decontamination tool.

Project FCT/EXPL/DTP-SAP/2338/2013 - VRad - Inactivation patterns of enteric viruses by ionizing radiation.

Matrix and dose rate influence the response of microorganisms to

gamma radiation and could be also important factors for

bioremediation.

http://dx.doi.org/10.1007/s00411-015-0617-2.

Virucidal efficiency of 99.99% for gamma irradiation at 6 kGy for tap water and wastewater. http://dx.doi.org/10.1128/AEM.01229-16.

0 2 4 6 8 10 120

1

2

3

4

5

6 FBS

50% FBS

10% FBS

tap water

DI water

PBS

wastewater

Lo

g10 (P

FU

/ml)

Dose (kGy)

Human Adenovirus

Survival curves to gamma radiation of human adenovirus type 5 (HAdV-5) for

several suspension matrices: phosphate-buffered saline (PBS), deionized

filtered water (DI water), tap water, fetal bovine serum (FBS), and wastewater

collected from a municipal wastewater treatment plant before tertiary

treatment.

High enteric virus load



Human Adenovirus - HAdV • Study the mechanisms of virus inactivation by ionizing radiation.

M 0 5 10 15 0 5 10 15 M

Dose (kGy)

HAdV2 HAdV5

Dose (kGy)

Nested PCR of extracted DNA genome from non-

irradiated and irradiated HAdV suspensions.

Genome

Capsid

M 0 0 5 5 10 10 15 15

HA

dV

2

HA

dV

5

HA

dV

2

HA

dV

5

HA

dV

2

HA

dV

5

HA

dV

2

HA

dV

5

Dose (kGy)

SDS-PAGE of capsid proteins from non-irradiated and

irradiated HAdV suspensions.

Studies suggest that viruses are the masters of

evolution and innovation in the web of life. They are

the simplest organisms with the capacity of using the

lowest energy to conserve life and its diversity.


Future work

• Study the potential add-value of e-

beam treatment regarding

bioactivity improvement (e.g.

antimicrobial, antioxidant activities).

• Study the antibiotic resistance

profile of ionizing radiation surviving

food microbiota.

E-BEAM FOOD

IRRADIATION

o Technical maintenance of LINAC.

• Development of attenuated

vaccines/vectors for drug delivery.

RADIOVIROLOGY

o Upgraded equipment for

genomic and proteomic analysis.

WA

ST

EW

AT

ER

VA

LO

RIZ

AT

IO

N

• Development of bioactive

compounds through the

valorization of wastes

treated by ionizing

radiation.


Sterilization services

Networking


Thank for your attention

[email protected]

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IONIZING RADIATION: a tool to control environmental ...c2tn.tecnico.ulisboa.pt/images/1st_c2tn_workshop/... · ionizing radiation in several matrices, and identify the radioresistance