Environmental and Molecular Mutagenesis - Legacy Tobacco ...

78 1989 EMS Abstracts
Notes
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
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SEL3CPIVE ANTIMUTAUENIC ACTZVITY GF TERKNALIA 1C~E9J~L! IN SALhiONEL14
TyyUlhUk2= . I .S .GRLVER and Saroj bAl,p . School of Lite Sciences, Guru
Nanak Lev University, Amritsar-143005, India .
Tecmiralin chebula is a eommon medicinal plant whose fruit is used in
"Ayurvedic" and "Unani' system of medicine as caaninative, exFectorant
and gastric disorders . Antimutagenicity of its water and chloroform
extracts of dried f wits was determined against two direct acting
mutagens, sodium azide and 4-nitro-o-phecylenediamine (NPD) in strains
TA1o0 and TA1535 and TA97a and TA98 respectively and S9 dependent
mutagen 2-aminofluorene (2-AF) in TA97a and TA9S of ~ .S,ynhimurium . It was'
obse rved that water ext ract s reduced NrL i nduced hi a revertant s i n both
TA97a and TA98 significantly but did not have any perceptible effect
against sodium az ;de induced his+ revertant in TA100 and TA1535 of
.Z,tvl)hlm yrium, The pre-incubation studies where the extract was incubated
at 370C for 30 minutes with the said mutegen prior to plating enhanced
the inhibitory effect . Autoclaving the water extract reduced its effect
but the reduction was not significant . The water extracts inhibited signi .
ficantly 2-AF reduced his+ revertants too in all the strains tested but
its effect inTA98 was striking as it reduced the revertants to spontaneous
level . No inhibitory effect was observed in any of the strains and against
all the test mutagens with chloroform extract . It appears that inhibitory
factor (antimutagen) is water soluble, heat stable and desnutagen .
COMYARISON OF TF1E ANTIMITTAUENIC EFFECT ( .F WACER Ey.TRAGTS OF TWU
DIFFEFtEhT VARIETIES OF INLIAN CGUSEbF :NIQf . I .S .GRGVER 6, AjpLMD liaur,
School of Life Sciences,Guru Nanak l :ev University, Amrit :.;ar, 1NDIA .
Indian gooseberry (Llnbiica Officinalis) is a very comnon medicinal
plant and its fruit is thv richest source of Vitamin C . Nntimutagenicity
ot the wate r extracts ot its two difterent varletiess was
tested against two direct acting.mutagens, sodium azido and 4-nltrcL
o-phenylenediaminr in TA1535 and 'l'A98 respectively using thn Ames
test . water extract of var .-I reduced the his+ revertants in TA98
upto 5r/. but its effect was not significant in TA1535 . Pre-incubation
of the extract with the mutagen at 370C for 30 min did~not have a
significant eff--ct in TA98 but reduction'of his+ revertants in TA1535
was . enhanced by pre-incubating the extract with sodium azide . Auto-oclaving
of ext ract reduced its inhibitory effect in TA98 but promoted
its effect in TA1535 . Water ext ract of var .-II showed a maximum of
52% inhibition in the sodium ezide inLluced frequency of his+
revertants in TA1535 but its effect was corvparatively less in TA98 .
P re-incubation of the extracts with the mutagen increased the
inhibitory effect in both the strains . 1Heating of the extracts did
rnt have -a significant effect on its inhibitory activity . Thus it
may be concluded from the results that both th ese varieties may have
different nutagenic facto rs .
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A GENETIC ASSAY FOR TNE DETECTION OF INEUPLOIDY AN? CLASTOGENICITY USING A
NONOCBRONOSONAL HYBRID CELL LINE . R . 6ud1 , R .S . Athwal . and S .S . Sandhu2 . 1Nsw
Jersey Medical School, Newark, NJ 07103 USA ; 2U .S . Environmental Protection Agency,
RTP, NC 27711 USA .
We have developed an assay for induced chromosomal anomalies based on the
quantitation of loss of a chromosome or chromosomal segment by growth of cells in
selection media . For this purpose, a mouse/human hybrid cell line containing human
chromosome 5 as the only human component has been produced . This chromosome S
carries two dominant selectable markers, Ecogpt, and a gene for sensitivity to
diptheria toxin (DTs) . Cultivation of these cells in DNEN containing mycophenolic
acid and xanthine (NX medium) selects for Ecogpt and thus for the retention of
chromosome 5 . The growth of these cells in the medium containing 6•thioguanine and
diptheria toxin (DT) gives the frequency of chromosome loss . Similarly, growth of
hybrid cells in MX medium containing DT (10'10l1) selects for the cells that have lost
the segment of chromosome 5 carrying DTs gene while retaining Ecogpt . This provides
a method to quantitate induced chromosome breaks . Preliminary results using model
compounds show a dose-related response for induced aneuploidy and chromosome breaks .
The same cell line can also be used to quantitate induced point mutations by growth
in the medium containing ouabain (10-3M) . A unified genetic assay for multiple
endpoints will enable the evaluation of test chemicals at doses relevant to human
exposure . (This is an abstract of a proposed presentation and does not necessarily
reflect U .S . EPA policy .)
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