Page 62 - Kutnar, Andreja, et al., eds., 2015. Proceedings of the 1st COST Action FP1307 International Conference - Life Cycle Assessment, EPDs, and modified wood. University of Primorska Press, Koper.
P. 62
ay
resistance
and
physicochemical
properties
of
wood
preservatives
based
on
extractives
from
Ocotea
acutifolia
leaves
Daniela
T.
Silva1*,
René
Herrera2*,
Berta
M.
Heinzmann3,
Jalel
Labidi4*
*Plaza
Europa
1,
20018,
San
Sebastian,
Spain,
University
of
the
Basque
Country,
1dthomas002@ikasle.ehu.eus,
2renealexander.herrera@ehu.eus,
4jalel.labidi@ehu.eus
3Avenida
Roraima
1000,
97105900,
Santa
Maria,
Brazil,
Federal
University
of
Santa
Maria,
berta.heinzamnn@gmail.com
Keywords:
antifungal
activity,
natural
compounds-‐based
products,
wood
preservative
The
toxicity
of
copper
components
on
wood
preservatives
propels
the
search
for
chemical
free
alternatives
products.
The
aim
of
this
study
is
to
evaluate
the
decay
resistance
of
some
low
impact
extracts
from
a
native
Brazilian
tree,
Ocotea
acutifolia
Nees
(Mez)
against
wood-‐rot
fungi.
Leaves
of
O.
acutifolia
were
collected
in
a
rural
area
in
the
South
of
Brazil
(at
29°37’
S;
53°52’
W;
203-‐207
m),
dried
at
room
temperature,
and
milled.
Subsequently,
powdered
leaves
(970
g)
were
extracted
by
Soxhlet
and
ethanol
obtaining
90
g
of
ethanolic
extract.
This
extract
was
dissolved
in
water
and
fractionated
by
consecutive
liquid/liquid
partition
by
chloroform,
ethyl
acetate,
and
butanol
(Egua
et
al.
2014).
Physicochemical
characterization
(thermogravimetric
analysis,
antioxidant
activity,
flavonoid,
and
total
phenolic
contents)
of
the
obtained
fractions
(butanolic
and
ethyl
acetate)
were
conducted.
Furthermore,
two
different
concentrations
(1
%
and
4
%)
of
extractives
of
O.
acutifolia
leaves
were
dissolved
in
ethanol
and
superficially
impregnated
(immersion
by
20
h)
on
downy
birch
laminated
wood
(Betula
pubescens
Ehrh.).
Afterwards,
the
treated
wood
samples
were
placed
in
contact
with
the
fungal
agent
(Trametes
versicolor
L.)
on
potato
dextrose
agar
medium
(PDA)
and
incubated
at
23
°C
±
2
°C
and
relative
humidity
of
60
%
±
5
%
until
the
control
samples
presented
10
%
weight
loss.
All
characterization
and
assays
were
compared
with
unfractionated
ethanolic
extract
(crude
extract).
The
results
in
Table
1
showed
significant
differences
in
relation
to
the
amount
of
phenolic
and
flavonoid
compounds
between
fractions
and
crude
extract.
Table
1:
Comparison
of
DPPH
assay
and
polyphenols
from
O.
acutifolia
leaves
extracts.
Sample
IC50
DPPH
scavenginga
Flavonoid
contentb
Total
phenolic
contentc
[mg
extract/mL)
[mg
QE/g]
[mg
GAE/g]
Crude
extract
1.10
±
0.08
C
83.94
±
1.98
C
178.75
±
12.95
C
Butanolic
fraction
0.55
±
0.03
A
112.43
±
1.87
B
405.09
±
16.79
A
Ethyl
acetate
fraction
0.74
±
0.07
B
178.93
±
1.03
A
360.04
±
16.19
B
aEffective
concentration
of
sample
required
to
50%
scavenge
of
DPPH
radical
by
probit
analysis,
bExpressed
as
quercetine
equivalent,
cExpressed
as
gallic
acid
equivalent.
Uppercase
letters
in
the
same
column
refer
to
means
statistically
different
by
Tukey
test
(P
<
0.05).
Results
are
exhibited
as
mean
±
standard
deviation.
50
resistance
and
physicochemical
properties
of
wood
preservatives
based
on
extractives
from
Ocotea
acutifolia
leaves
Daniela
T.
Silva1*,
René
Herrera2*,
Berta
M.
Heinzmann3,
Jalel
Labidi4*
*Plaza
Europa
1,
20018,
San
Sebastian,
Spain,
University
of
the
Basque
Country,
1dthomas002@ikasle.ehu.eus,
2renealexander.herrera@ehu.eus,
4jalel.labidi@ehu.eus
3Avenida
Roraima
1000,
97105900,
Santa
Maria,
Brazil,
Federal
University
of
Santa
Maria,
berta.heinzamnn@gmail.com
Keywords:
antifungal
activity,
natural
compounds-‐based
products,
wood
preservative
The
toxicity
of
copper
components
on
wood
preservatives
propels
the
search
for
chemical
free
alternatives
products.
The
aim
of
this
study
is
to
evaluate
the
decay
resistance
of
some
low
impact
extracts
from
a
native
Brazilian
tree,
Ocotea
acutifolia
Nees
(Mez)
against
wood-‐rot
fungi.
Leaves
of
O.
acutifolia
were
collected
in
a
rural
area
in
the
South
of
Brazil
(at
29°37’
S;
53°52’
W;
203-‐207
m),
dried
at
room
temperature,
and
milled.
Subsequently,
powdered
leaves
(970
g)
were
extracted
by
Soxhlet
and
ethanol
obtaining
90
g
of
ethanolic
extract.
This
extract
was
dissolved
in
water
and
fractionated
by
consecutive
liquid/liquid
partition
by
chloroform,
ethyl
acetate,
and
butanol
(Egua
et
al.
2014).
Physicochemical
characterization
(thermogravimetric
analysis,
antioxidant
activity,
flavonoid,
and
total
phenolic
contents)
of
the
obtained
fractions
(butanolic
and
ethyl
acetate)
were
conducted.
Furthermore,
two
different
concentrations
(1
%
and
4
%)
of
extractives
of
O.
acutifolia
leaves
were
dissolved
in
ethanol
and
superficially
impregnated
(immersion
by
20
h)
on
downy
birch
laminated
wood
(Betula
pubescens
Ehrh.).
Afterwards,
the
treated
wood
samples
were
placed
in
contact
with
the
fungal
agent
(Trametes
versicolor
L.)
on
potato
dextrose
agar
medium
(PDA)
and
incubated
at
23
°C
±
2
°C
and
relative
humidity
of
60
%
±
5
%
until
the
control
samples
presented
10
%
weight
loss.
All
characterization
and
assays
were
compared
with
unfractionated
ethanolic
extract
(crude
extract).
The
results
in
Table
1
showed
significant
differences
in
relation
to
the
amount
of
phenolic
and
flavonoid
compounds
between
fractions
and
crude
extract.
Table
1:
Comparison
of
DPPH
assay
and
polyphenols
from
O.
acutifolia
leaves
extracts.
Sample
IC50
DPPH
scavenginga
Flavonoid
contentb
Total
phenolic
contentc
[mg
extract/mL)
[mg
QE/g]
[mg
GAE/g]
Crude
extract
1.10
±
0.08
C
83.94
±
1.98
C
178.75
±
12.95
C
Butanolic
fraction
0.55
±
0.03
A
112.43
±
1.87
B
405.09
±
16.79
A
Ethyl
acetate
fraction
0.74
±
0.07
B
178.93
±
1.03
A
360.04
±
16.19
B
aEffective
concentration
of
sample
required
to
50%
scavenge
of
DPPH
radical
by
probit
analysis,
bExpressed
as
quercetine
equivalent,
cExpressed
as
gallic
acid
equivalent.
Uppercase
letters
in
the
same
column
refer
to
means
statistically
different
by
Tukey
test
(P
<
0.05).
Results
are
exhibited
as
mean
±
standard
deviation.
50
