Decomp products 8-1 11min SUN

Question 1

decomp products are formed
how many classes and what

Answer 1

Occur after death
o Autolysis of tissues and/or
o Partly in bacterial [putrefaction] metabolism of endogenous compounds
o Grouped into three classes
 Alkaloidal compounds [basic]
 Acidic compounds
 Neutral compounds

Question 2

how do you describe decomp products

Answer 2

Called ptomains
o React like alkaloids upon extraction
o Basic nitrogenous organic compounds produced by bacterial putrefaction of
proteins

Question 3

Van hoffs rule

Answer 3

(rule of 10)

o Velocity of chemical rxn (decomposition) increases ~2+ times with each 10 °C in
temp
 Temp approximates normal rxn temp

Question 4

common decomp products

Answer 4

Predicted by bacterial
o Studied either biogenic amines
 Tryptamine, phenylethylamine, putrescene, cadaverine, histamine…
o Levels of all amines increased with increasing putrefaction,
 Except spermidine and spermine, which decreased

Question 5

B-phenylethylamine

Answer 5

Naturally occurring substance and common decomposition product
 Derived from the breakdown of amino acid: decarboxylation of phenylamine
May cause positive result in some immunoassay [amphetamine] tests

Question 6

In addition to interfering compounds, what else can be found

Answer 6

target analytes

Question 7

common target analytes that are formed

Answer 7

Ethyl alcohol formation/loss
 Formation of other volatile compounds:
o Acetone, IPA
o VOCs
 GHB formation
 Carbon monoxide
 Cyanide

Question 8

what eeffect ethyl alcohol formation

Answer 8

o Ambient temp

Question 9

Endogenos ethyl alcohol result of microbial activity on what compounds

Answer 9

o Glucose
o Lactate
o Glycerol

o Amino acids
o Ribose

Question 10

primary source ofendogenous ethyl alcohol

Answer 10

glucose

Question 11

what Tissues high in glucose storage capacity site of greatest potential ethyl alcohol
production

Answer 11

Liver
 Skeletal muscles
 Lungs
 Heart

Question 12

what is ideal specimen for ethyl alcohol

Answer 12

Vitreous humor

Question 13

urine is poor or good for mucrobial ethoh synthesis

Answer 13

Urine poor medium for microbial EtOH synthesis
 Exception – diabetic/UTI

Question 14

other putrafective bases

Answer 14

Cadaverine- no other drug that has a molecular peak at m/z 56
Putrescine- problem since many drugs have M.p at 72