Preparation of low-molecular-weight and high-sulfate-content chitosans under microwave radiation and their potential antioxidant activity in vitro.

Carbohydrate research · 2004 · Unclear · Insufficient evidence

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UnclearInsufficient evidencePaper 6411

Study snapshot

PublicationCarbohydrate research · 2004

Study typein_vitro

Reported directionUnclear

Evidence ratingInsufficient

Abstract

In the present paper microwave radiation has been used to introduce N-sulfo and O-sulfo groups into chitosan with a high degree of substitution and low-molecular weight. The sulfation of chitosan was performed in microwave ovens. It was found that microwave heating is a convenient way to obtain a wide range of products of different degrees of substitution and molecular weight only by changing reaction time or/and radiation power. Moreover, microwave radiation accelerated the degradation of sulfated chitosan, and the molecular weight of sulfated chitosan was considerably lower than that obtained by traditional heating. There are no differences in the chemical structure of sulfated chitosan obtained by microwave and by conventional technology. FTIR and 13C NMR spectral analyses demonstrated that a significantly shorter time is required to obtain a satisfactory degree of substitution and molecular weight by microwave radiation than by conventional technology. In this present paper, we also determined antioxidant activity of low-molecular-weight and high-sulfate-content chitosans (LCTS). The results showed LCTS could scavenge superoxide and hydroxyl radical. Its IC50 is 0.025 and 1.32 mg/mL, respectively. It is a potential antioxidant in vitro.

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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 directionunclear

PopulationNot supplied

Sample sizeNot supplied

ExposureNot supplied

Evidence strengthInsufficientConfidence: 74% · Peer reviewed: yes

Main findings

Microwave heating was used to sulfated chitosan and produced products with varying degrees of substitution and molecular weight by changing reaction time and/or radiation power. Microwave radiation accelerated degradation and yielded considerably lower molecular weight than traditional heating, while no differences in chemical structure were reported between microwave and conventional methods. Low-molecular-weight, high-sulfate-content chitosans scavenged superoxide and hydroxyl radicals in vitro (IC50 0.025 and 1.32 mg/mL, respectively).

Outcomes measured

Chitosan sulfation (degree of substitution; N-sulfo and O-sulfo groups)
Molecular weight/degradation of sulfated chitosan
Chemical structure comparison vs conventional heating (FTIR, 13C NMR)
In vitro antioxidant activity (superoxide and hydroxyl radical scavenging; IC50)

View raw extracted JSON

{
  "study_type": "in_vitro",
  "exposure": {
    "band": null,
    "source": "microwave oven",
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": null,
  "sample_size": null,
  "outcomes": [
    "Chitosan sulfation (degree of substitution; N-sulfo and O-sulfo groups)",
    "Molecular weight/degradation of sulfated chitosan",
    "Chemical structure comparison vs conventional heating (FTIR, 13C NMR)",
    "In vitro antioxidant activity (superoxide and hydroxyl radical scavenging; IC50)"
  ],
  "main_findings": "Microwave heating was used to sulfated chitosan and produced products with varying degrees of substitution and molecular weight by changing reaction time and/or radiation power. Microwave radiation accelerated degradation and yielded considerably lower molecular weight than traditional heating, while no differences in chemical structure were reported between microwave and conventional methods. Low-molecular-weight, high-sulfate-content chitosans scavenged superoxide and hydroxyl radicals in vitro (IC50 0.025 and 1.32 mg/mL, respectively).",
  "effect_direction": "unclear",
  "limitations": [],
  "evidence_strength": "insufficient",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "microwave radiation",
    "microwave heating",
    "chitosan",
    "sulfation",
    "N-sulfo",
    "O-sulfo",
    "degree of substitution",
    "molecular weight",
    "FTIR",
    "13C NMR",
    "antioxidant activity",
    "superoxide",
    "hydroxyl radical",
    "IC50",
    "in vitro"
  ],
  "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: 10.1016/j.carres.2004.08.013
PubMed: 15476712

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