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Bog Bodies

Bog Bodies. What's a bog?.

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Bog Bodies

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  1. Bog Bodies

  2. What's a bog? A bog is a mire that accumulates peat, a deposit of dead plant material—often mosses, and in a majority of cases, Sphagnum moss. Bogs occur where the water at the ground surface is acidic and low in nutrients. Water flowing out of bogs has a characteristic brown color, which comes from dissolved peat tannins.

  3. What are bog bodies? The term bog bodies is used to refer to human burials, some likely sacrificed, placed within peat bogs of Denmark, Germany, Holland, Britain, and Ireland and naturally mummified. The highly acidic peat acts as a preservative, leaving the clothing and skin intact. The oldest known bog body from Northern Europe is the Koelbjerg woman from Denmark, who has been dated to 8000 BCE, during the Mesolithic period.

  4. How are they preserved? The reason that bogs have a high level of preservation is because they are both acidic and oxygen-poor. The cold water also hinders putrefaction and insect activity. Sphagnum mosses and the presence of tannin add to the preservation by having anti-bacterial properties.

  5. Tannin Yellowish or brownish solid compounds found in many plants and used as tanning agents, mordants, medical astringents, etc. Tannins are derivatives of gallic acid with the approximate formula C76H52O46 Also called tannic acid which attributes to the acidity of the bog

  6. Sphagnum Moss Commonly called peat moss due to its prevalence in wet habitats where it contributes to the formation of peat bogs and mires

  7. Sphanum Moss to Sphagnan Sphagnanis a pectin-like carbohydrate polymer which is covalently linked to cellulosic and amyloid-like chains in Sphagnum moss. Autohydrolysis liberates the sphagnan into the surrounding water as dead moss converts into peat.

  8. What can Sphagan do? Sphagnan is a preservative substance with antimicrobial and tanning properties. The Maillard reaction between the free amino-groups of collagen and reactive carbonyl groups accounts for the tanning. The preservative qualities are ultimately attributable to the Maillard reaction between the substance sphagnan and any compound or polymer containing a free primary amino-group, including ammonia.

  9. Maillard Reactions • The Maillard reaction is a form of nonenzymatic browning. It results from a chemical reaction between an amino acid and a reducing sugar, usually requiring heat.

  10. Mackeral Skin Samples Scanning electron micrographs of mackerel skin before and after treatment with different tanning agents. a: Untreated skin (M-O); b: skin treated with borohydride-reduced sphagnan (M-RS); c: skin treated with tannic acid (M-T); and d: skin treated with sphagnan (M-S). Size bar: 0.1 mm.

  11. Thermal Analysis of Mackeral Skin Samples Differential thermal analysis of mackerel skin before and after treatment with different tanning agents. M-O, untreated skin; M-S, skin treated with sphagnan; M-RS, skin treated with borohydride-reduced sphagnan; M-T, skin tanned with tannic acid.

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