Modulation of the catalytic activity of free and immobilized peroxidase by extremely low frequency electromagnetic fields: dependence on frequency.

Bioelectromagnetics · 2005 · Mixed · Low evidence

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MixedLow evidencePaper 5203

Study snapshot

PublicationBioelectromagnetics · 2005

Study typein_vitro

Reported directionMixed

Evidence ratingLow

Abstract

A study of the influence of electromagnetic fields (EMF) of various frequencies, from 50 up to 400 Hz, on the catalytic activity of soluble and insoluble horseradish peroxidase (POD) was carried out. To simulate the conditions in which the enzyme operates in vivo, the POD was immobilized by entrapment on a gelatin membrane or by covalent attachment on a nylon graft membrane. The rate of inactivation of the soluble POD was found to exhibit positive and negative interactions with the 1 mT applied magnetic field, with an optimum positive effect at 130 Hz. The immobilized PODs, on the contrary, do not exhibit negative interactions, but show a maximum positive interaction at 150 Hz when entrapped and at 170 Hz when covalently attached. At 50 Hz and at frequencies higher than 250 Hz no effects were observed with insoluble POD. The optimum frequency of positive interaction between the EMF and the catalytic activity of the insoluble enzymes is shifted with respect to that of the soluble enzymes towards higher frequencies, the size of the shifts being dependent on the intensity of the physical forces involved in the immobilization process.

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AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typein_vitro

Effect directionmixed

PopulationNot supplied

Sample sizeNot supplied

ExposureELF

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

Electromagnetic fields from 50–400 Hz at 1 mT modulated horseradish peroxidase activity in a frequency-dependent manner. Soluble POD showed both positive and negative interactions with an optimum positive effect at 130 Hz, while immobilized POD (gelatin-entrapment or covalent attachment) showed only positive interactions with maxima at 150 Hz and 170 Hz, respectively; no effects were observed for insoluble POD at 50 Hz or above 250 Hz.

Outcomes measured

Catalytic activity of horseradish peroxidase (POD)
Rate of inactivation of soluble POD
Frequency dependence of EMF interaction with POD activity (soluble vs immobilized)

Limitations

No sample size reported in abstract
Exposure duration and other exposure parameters beyond field intensity and frequency not reported in abstract
In vitro enzyme system; relevance to in vivo conditions not established in abstract

View raw extracted JSON

{
  "study_type": "in_vitro",
  "exposure": {
    "band": "ELF",
    "source": null,
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": null,
  "sample_size": null,
  "outcomes": [
    "Catalytic activity of horseradish peroxidase (POD)",
    "Rate of inactivation of soluble POD",
    "Frequency dependence of EMF interaction with POD activity (soluble vs immobilized)"
  ],
  "main_findings": "Electromagnetic fields from 50–400 Hz at 1 mT modulated horseradish peroxidase activity in a frequency-dependent manner. Soluble POD showed both positive and negative interactions with an optimum positive effect at 130 Hz, while immobilized POD (gelatin-entrapment or covalent attachment) showed only positive interactions with maxima at 150 Hz and 170 Hz, respectively; no effects were observed for insoluble POD at 50 Hz or above 250 Hz.",
  "effect_direction": "mixed",
  "limitations": [
    "No sample size reported in abstract",
    "Exposure duration and other exposure parameters beyond field intensity and frequency not reported in abstract",
    "In vitro enzyme system; relevance to in vivo conditions not established in abstract"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "extremely low frequency",
    "ELF",
    "electromagnetic fields",
    "magnetic field",
    "1 mT",
    "50–400 Hz",
    "horseradish peroxidase",
    "enzyme activity",
    "immobilization",
    "gelatin membrane",
    "nylon graft membrane",
    "frequency dependence"
  ],
  "suggested_hubs": []
}

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AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1002/bem.20059
PubMed: 15672368

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