Perbandingan Sifat Sifat Kayu Jati Berdasarkan Pengelolaan Hutan Rotasi Panjang Versus Rotasi Pendek

COMPARISON OF TEAK WOOD PROPERTIES
ACCORDING TO FOREST MANAGEMENT:
SHORT AND LONG ROTATION

DWI ERIKAN RIZANTI

GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2017

STATEMENT
I declare that this thesis entitled Comparison of Teak Wood Properties
According to Forest Management: Short and Long Rotation is my own work with
the direction of the supervising committee and has not been submitted in any form
for any college except in AgroParisTech ENGREF, France (required by Double
Degree Program). Information and quotes from journals and books have been
acknowledged and mentioned in the thesis where they appear. All complete
references are given at the end of the paper.
I understand that my thesis will become part of the collection of Bogor
Agricultural University. My signature below gives the copyright of my thesis to

Bogor Agricultural University.

Bogor, March 2017
Dwi Erikan Rizanti
NIM E251140071

SUMMARY
DWI ERIKAN RIZANTI. Comparison of Teak Wood Properties According to
Forest Management: Short and Long Rotation. Supervised by WAYAN
DARMAWAN and PHILIPPE GERARDIN.
Teak (Tectona grandis L.f.) is one of the most important tropical hardwood
tree species in Indonesia. It has been processed to wood furniture in large quantities
to fulfill an increasing need of both local and international consumers. To satisfy
the increasing demand for wood products, teak wood has been supplied from the
State forests (Perhutani) and Community teak plantations. Community teak has
been harvested at shorter age rotations (7–10 years) than Perhutani teak (40–60
years).
This paper discusses the characterization of technological properties of short
and long rotation teak wood based on extractives contents, chemical composition,
density, vessel frequency and wood porosity, swelling, water sorption isotherm,

bending strength (modulus of rupture – MOR and modulus of elasticity - MOE),
Brinell hardness, wettability, color changes, and decay durability.
The results show that short rotation teak had lower extractives content, lower
density, higher vessel frequency and porosity, lower dimensional stability in
swelling and higher change in mass values in water sorption and desorption, lower
MOE, MOR, and Brinell hardness, higher and better wettability, and lower
durability compared to long rotation teak. These results also show that the short
rotation teak was not remarkably different in swelling, MOE and MOR, and Brinell
hardness compared to long rotation teak, although it was less dense and less durable
due to lower heartwood and extractives contents. Therefore, careful attention
should be given to the use of short rotation teak in some wood-processing
technologies.
Keywords: Short and long rotation teak, extractives, wettability, durability.

RINGKASAN
DWI ERIKAN RIZANTI. Perbandingan Sifat-Sifat Kayu Jati Berdasarkan
Pengelolaan Hutan: Rotasi Panjang versus Rotasi Pendek. Dibimbing oleh
WAYAN DARMAWAN dan PHILIPPE GERARDIN.
Jati (Tectona grandis L.f.) merupakan salah satu jenis kayu tropis yang paling
penting di Indonesia. Kayu jati di Indonesia diproses menjadi produk furniture

dalam jumlah besar untuk memenuhi permintaan lokal dan internasional. Untuk
memenuhi peningkatan permintaan produk, kayu jati dipasok dari Hutan Negara
(Perhutani) dan Hutan Tanaman Rakyat (Community teak plantations). Jati rakyat
dipanen pada rotasi yang lebih pendek yaitu sekitar 7-10 tahun dibandingkan jati
Perhutani (40-60 tahun).
Penelitian ini membahas karakterisasi sifat-sifat teknologi pada kayu jati
rotasi panjang dan rotasi pendek berdasarkan kandungan ekstraktif, komposisi
kimia kayu, kerapatan (density), jumlah vessel dan porositas kayu, swelling, water
sorption isotherm, kekuatan lentur (modulus of rupture - MOR dan modulus
elastisitas - MOE), kekerasan kayu, keterbasahan (wettability), perubahan warna,
dan daya tahan terhadap jamur pelapuk.
Hasil penelitian menunjukkan bahwa jati rotasi pendek memiliki kandungan
ekstraktif, kerapatan, stabilitas dimensi yang lebih rendah, dan memiliki nilai MOE,
MOR dan kekerasan yang lebih rendah, serta memiliki daya tahan terhadap jamur
pelapuk yang lebih rendah dibandingkan kayu jadi rotasi panjang. Jati rotasi pendek
memiliki jumlah vessel yang lebih banyak dan porositas yang lebih tinggi, memiliki
nilai perubahan massa yang lebih tinggi pada fenomena water sorption isotherm,
keterbasahan yang lebih tinggi dan lebih baik dibandingkan dengan jati rotasi
panjang. Hasil ini juga menunjukkan bahwa nilai swelling, MOE dan MOR, dan
kekerasan pada jati rotasi pendek tidak sangat berbeda dibandingkan dengan jati

rotasi panjang, meskipun jati rotasi pendek memiliki kerapatan yang rendah dan
daya tahan terhadap jamur pelapuk yang rendah karena rendahnya porsi kayu teras
dan kandungan ekstraktif pada jati rotasi pendek. Oleh karena itu, perhatian khusus
perlu diberikan dalam hal penggunaan kayu jati rotasi pendek pada beberapa
teknologi pengolahan kayu.
Kata kunci: Jati rotasi pendek dan rotasi panjang, ekstraktif, wettability, durability.

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COMPARISON OF TEAK WOOD PROPERTIES
ACCORDING TO FOREST MANAGEMENT:
SHORT AND LONG ROTATION

DWI ERIKAN RIZANTI

Thesis
In partial fulfillment of the requirements for the degree of
Master of Science
at
Bogor Agricultural University

GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2017

External Examiner:

Dr Effendi Tri Bahtiar, SHut, MSi

FOREWORD
All praise and gratitude to Allah SWT so that the author could finish this
scientific work entitled Comparison of Teak Wood Properties According to Forest

Management: Short Versus Long Rotation. The study is expected to provide
scientific information on the short and long rotation in teak wood in Indonesia.
The special thank goes to my helpful supervisor Prof Wayan Darmawan, Prof
Philippe Gérardin and Dr Stéphane Dumarçay. The supervision, advice and support
that they gave truly help the progression and smoothness of my study.
My grateful thanks also go to Prof André Merlin dan Dr Béatrice George for
a big contribution and advice many times during my research, Joel Hamada, Solava
Salman, Dr Julien Ruelle, Clément L’hostis, Marylin Harroué for helping me to
work in laboratory and for all member of Laboratoire d’Etudes et de Recherche sur
le Matériau Bois (LERMAB), Université de Lorraine, Vandoeuvre-lès-Nancy
Cedex, France; Crittbois ENSTIB, Epinal Cedex, France; and laboratory of wood
quality INRA Champenoux, Nancy, France, Prof Meriém Fournier, Dr Holger
Wernsdorfer, and for all the staffs of AgroParisTech and Université de Lorraine.
Thanks also to my beloved parents, Mr. Rizal Ependi and Mrs. Hapizoh, my
sister and brothers, Youlana Hapriza, Muhammad Seriz Dimas, Muhammad Firas
Banna, Faiz Ahmad Nadhif, my closest friend Rakhmad Bagus Prakoso and the
whole family, for all the prayers and love. And also thanks to all master students of
Science and Technology of Forest Products 2014, my best friend Nursinta Arifiani
Rosdiana, my others friends Moustafa Hassan and Christ Bopenga.
Finally, I thank to Indonesian Ministry of Education “Beasiswa Unggulan

programme” for its financial support. Without the support I simply could not come
to study the Master program.
The author recognizes that this research is still far from perfect. Therefore,
suggestions and constructive criticism are expected to improve this work.
Bogor, March 2017
Dwi Erikan Rizanti

TABLE OF CONTENTS
TABLE OF CONTENTS

vi

LIST OF TABLES

vi

LIST OF FIGURES

vi

LIST OF APPENDIXES

vi

1 INTRODUCTION
Background
Formulation
Objective
Benefits

1
1
1
2
2

2 METHODS
Tools and Materials
Data Analyzing

2
2
8

3 RESULTS AND DISCUSSION
Extractives Content
Chemical Composition
Density
Microscopic Wood Anatomy
Swelling
Water Sorption Isotherm
MOE and MOR
Brinell Hardness
Wettability
Color Changes
Decay Durability

9
9
10

12
13
13
14
15
16
17
19
20

4 CONCLUSION

21

REFERENCES

22

APPENDIXES

25

CURRICULUM VITAE

28

LIST OF TABLES
1 Extractives content of short rotation and long rotation teak wood
obtained by successive extractions with four solvents of increasing
polarity
9
2 Major compounds identified by GCMS in the extractives of short rotation
and long rotation teak wood
11
3 Holocellulose, cellulose, hemicellulose, and lignin Klason of short
rotation and long rotation teak wood
12

LIST OF FIGURES
1 The schematic diagram of tests specimens preparation
3
2 Transverse section of long rotation (A) and short rotation teak wood
(B)
13
3 Dimensional stability of short rotation and long rotation teak wood 14
4 Sorption and desorption isotherm of short rotation and long rotation teak
wood at 20˚ C
15
5 MOE and MOR of short and long rotation teak wood
16
6 Brinell hardness of short and long rotation teak wood
17
7 Contact angle of short rotation and long rotation teak wood using water
(a) and glycerol (b) as liquid
18
8 Color changes due to irradiation at different irradiation times at the
surface of long rotation (a) and short rotation teak wood (b)
19
9 Durability of long rotation and short rotation teak wood samples to the
white rot decay fungus C. versicolor and the brown rot decay fungus P.
Sanguineus
20

LIST OF APPENDIXES
1 Dichloromethane extract chromatogram of long rotation (teak a) and
short rotation teak wood (teak b)
25
2 Acetone extract chromatogram of long rotation (teak a) and short rotation
teak wood (teak b)
26
3 Toluene-Ethanol extract chromatogram of long rotation (teak a) and
short rotation teak wood (teak b)
27

1 INTRODUCTION
Background
Teak (Tectona grandis L.f.) is one of the most important tree species in
tropical regions and probably the most highly-valued hardwood. It is also one of
the most important tropical hardwood tree species in Indonesia. It is planted widely
in Java by Perhutani, a state forest enterprise in Indonesia, which is responsible for
the management of teak. The teak planted by Perhutani has been felled in age of 40
to 60 years (long rotation teak) and processed for shipbuilding, outdoor equipment,
and furniture in large quantities. Due to the increasing demand for teak wood as a
raw material and to satisfy it, much of teak wood supply has been from community
teak plantations which planted and managed by communities and private companies
not only in Java but also in other parts of Indonesia.
Community teak trees in Indonesia grow well and fast in the Indonesian
regions where they are planted. However, community teak has been harvested at
short age of 7 to 10 years (short rotation teak) and it can be expected to contain a
high proportion of juvenile wood. In comparison with mature wood, juvenile wood
is made of smaller and shorter fibers with thinner walls and larger microfibril angles,
lower density, and lower strength properties (Evans et al. 2000; Koubaa et al. 2005;
Clark et al. 2006; Adamopoulus et al. 2007; Gryc et al. 2011). It is well known that
characteristics of juvenile wood contribute to undesirable solid wood properties
(Zobel 1984). It may cause serious problems for quality products, especially veneer
or solid wood products. This is due to its low bending strength and dimensional
instability. Darmawan et al. (2015) also reported that short rotation teak has lower
heartwood content than long rotation teak. Heartwood portion of the short rotation
teak at 10 years is 40%, whereas the long rotation teak at the age of 40 years is 80%.
This causes lower resistance of short rotation teak wood that would restrict its
utilization to some extent although it might still be superior to many other less
resistant timbers of fast growing plantations like Sengon (Paraserianthes
falcataria), and Jabon (Neolamarckia [Anthocephalus] cadamba).
Although Darmawan et al. (2015) have been doing research on short rotation
and long rotation teak wood to characterize their profiles and average trends in
density, shrinkage, fiber length, microfibril angle (MFA), and bending strength
(Modulus of rupture - MOR and Modulus of elasticity - MOE) as a function of
radial increments from pith to bark, however, little is known on their chemical
composition, extractives content, wettability, color changes, and durability.
Therefore, investigating and characterizing those properties will lead to better
utilization of the short rotation and long rotation teak woods.

Formulation
Community teak is a fast growing species where its wood properties
associated to juvenile wood is suspected to be a potential limit for industrial use
than long rotation teak wood. However, juvenility is not the only drawback for short
rotation teak, some technological properties affecting its utilization are also little
known.

2
Objective
The present study aims to investigate the comparison of wood properties
between short rotation and long rotation teak wood and the effects of wood
chemical composition on its technological properties conditioning its utilization.

Benefits
The study is expected to provide scientific information on the technological
properties of short rotation and long rotation teak wood. This properties will provide
the scientific development to wood science and technology. It would also be
beneficial for the industry to be able selecting appropriate processing technology so
that the final product has a good quality.

2 METHODS
Tools and Materials
1.

Teak trees selection and tests specimens preparation

Sample trees of teak (Tectona grandis) were obtained from plantation forests
managed by the state owned enterprise Perhutani, and the local community in Java,
Indonesia. The plantation sites were located at East Java for the Perhutani teak (long
rotation teak), and at the community forest Bogor West Java for the Community
teak (short rotation teak). Differences in growing conditions (environment, genetics,
and silviculture) between West Java and East Java resulted in variations in the teak
growth. The sample trees which were straight stems and free from external defects,
were selected to minimize tree-to-tree variation. The long rotation trees were 40
years in the age and 30 cm in average diameter at breast height level. The short
rotation trees were 10 years in the age, 6-10 m in height of branch-free stem, and
24 cm in average diameter at breast height level (1.3 m above ground level). After
felling the trees, one log section 2 m in length was taken from each tree at the bottom
part of the stem. The sample logs were wrapped in plastic, kept cold, and maintained
in the green condition before they were transported to the wood workshop for
preparation of test specimens.
The sample boards (200 x 100 x 20 mm³) were cut from the sample logs using
a band saw. Two kind of wood specimens of teak wood measuring 200 x 100 x 20
mm3 (L, T, R) were prepared. All samples (air-dried) were obtained from the same
teak board and used further for the preparation of smaller samples necessary for
characterization of different wood properties as described in Figure 1.

3

Figure 1 The schematic diagram of tests specimens preparation
The samples of 200 x 100 x 20 mm3 were cut to prepare samples of 30 x 20 x
10 mm3 for swelling test (Edou Engonga 1999, 2000), samples of 200 x 20 x 5 mm3
for mechanical tests (MOE, MOR) (EN 310), samples of 200 x 20 x 20 mm3 for
Brinell hardness test (EN 1534), samples of 200 x 20 x 5 mm3 for wettability test,
and samples of 30 x 20 x 5 mm3 for durability test (EN 113).

2.

Determination of the amount of extractives

Short rotation and long rotation teak wood samples were ground to fine
sawdust before drying at 103°C. Sequential extraction of each wood powder,
approximately 10 g was carried out in a Soxhlet apparatus using successively four
solvents of increasing polarity: dichloromethane, acetone, toluene/ethanol (2/1,
(v/v)) and water. After extraction, organic solvents were evaporated under vacuum
using a rotary evaporator while water was freeze–dried. Crude extracts were stored
in desiccators under vacuum for final drying and weighed to determine extractives
content based on moisture-free wood powder. Dried extractives were stored in a
freezer before GC–MS analyses.

3.

GC-MS analysis

A Clarus 500 GC gas chromatography (Perkin Elmer) was used for this
analysis. Gas chromatography was carried out on capillary column (J&W Scientific
DB-5, 30 m × 0.25 mm × 0.25 µm). Two miligrams of dry extract was dissolved in
50–100 µL of N,O-bis(trimethylsilyl) trifluoroacetamide containing 1%
trimethylchlorosilane (BSTFA/1% TMCS). The solution was vortex-stirred and
heated at 70 ˚C. After evaporation of the solvent, the residue was diluted in 1 mL
of ethyl acetate. The gas chromatography was equipped with electronically
controlled split/splitless injection port. The injection (1 µL) was performed at 250
˚C in the splitless mode. Helium was used as carrier gas at constant flow (1 mL/min).
Chromatographic conditions were as follows: initial temperature 80 ˚C, 2 min

4
isothermal, 10 ˚C min−1 to 190 ˚C, 15 ˚C min−1 to 280 ˚C, 5 min isothermal, 10 ˚C
min−1 to 300 ˚C, 14 min isothermal. Ionization was achieved by electron impact (20
or 70 eV ionization energy). Most of the components were identified by comparing
the mass spectra with the NIST Library database with match and reverse match
factors above 0.750.

4.

Chemical composition

Holocellulose
To 2.5 g of powder, add 80 mL of hot distilled water, 0.5 mL acetic acid, and
1 g of sodium chlorite in a 250-ml Erlenmeyer flask. An optional 25-mL
Erlenmeyer flask was inverted in the neck of the reaction flask to condense vapor.
The mixture was heated in a water bath at 70°C. After 1 hour, 0.5 mL of acetic acid
and 1 g of sodium chlorite were added. Addition of 0.5 ml acetic acid, and 1 g of
sodium chlorite was repeated every hour until the residual solid material turns to
white indicating the removal of most of lignin fraction. It usually takes 6 to 8 hours
of reaction. Holocellulose was filtered on filter paper using a Buchner funnel until
the filtrate becomes colorless, washed with acetone, dried at 103°C for 24 hours
and weighed. The lignin content is determined by difference between the dry initial
extracted free mass of wood and the dry holocellulose mass (Rowell 2005).
Cellulose
The cellulose was obtained by the Kurschner and Hoffner method using nitric
acid in ethanol (HNO3 (16N), ethanol (95%)) (Antunes 2000). One gram of extracts
free sawdust was placed in a 250 mL flask. Forty mL of ethanol and 10 mL of nitric
acid was added and the mixture placed under reflux at 100˚C. After one hour, the
alcoholic nitric acid solution was discarded and a fresh volume was added. This
operation was repeated one additional time. After the third hour of hydrolysis, the
cellulose was washed with ethanol, filtered, dried in an oven at 103˚C for 24 hours
and weighed. The cellulose content is calculated using the following formula:
Cellulose content (%) = (cellulose mass / initial mass sawdust) x 100
Hemicellulose
Hemicellulose content was obtained by difference between holocellulose
content and cellulose content. The hemicellulose content is calculated using the
following formula:
Hemicellulose content (%) = Holocellulose (%) – Cellulose (%)
Lignin
The lignin fraction was obtained by the method performed according to
Nguila et al. (2007), which consists in removing polysaccharides (holocellulose).
A mass of 0.175 g dried extract free sawdust was placed in a 50 mL centrifuge tube.

5
Sulfuric acid (97.5%) of 1.5 mL was added to the sawdust. The tubes were closed
and placed in a water bath equipped with a stirring system at 30˚C for 1 hour. After
this period, the mixture was diluted with 42 mL of distilled water to obtain a sulfuric
acid concentration of 30%. The tubes were closed and autoclaved for 1 hour and
half at 120˚C. After autoclaving, the mixture was diluted with 100 mL of distilled
water and filtered on a Buchner funnel. The black residue of Klason lignin obtained
was dried at 103˚C for 48 hours until constant mass. Klason lignin content is
determined by the following formula:
Klason lignin content (%) = (Mass of lignin / 0.175) x 100

5.

Density measurement

Density was calculated as the air-dried mass (moisture content 12-15%)
divided by the air-dried volume of the sample, using the following equation:
ρ=

�
�

where ρ is the density of the wood (kg/m³), m is the air-dried mass (kg), and V is
the air-dried volume (m³). Sample dimensions were measured along the radial,
tangential, and longitudinal directions using a 0.01-mm precision caliper in airdried condition.

6.

Microscopic wood anatomy measurements

Thin transversal sections (12 μm in thickness) were prepared by using a
sliding microtome equipped with a tungsten blade. Observations were made on
undamaged thin slice after coloration with Safranin 1% and Blue Astra 1% were
used in order to easily study the cell structure. Digital images of transverse sections
were captured with a digital camera mounted on photonic microscope and analyzed
with the ImageJ 1.47s software to determine the vessel area, vessel frequency
(vessel number per unit area), and wood porosity.

7.

Swelling test

The method was performed according to Edou Engonga (1999) and Edou
Engonga (2000). Six replicates (30 x 20 x 10 mm3) of short and long rotations teak
wood were dried for 48 hours at 103 oC. Test blocks were soaked in water in a
beaker. The beaker was placed in a desiccator and subjected to vacuum (30 mbar)
for 1 hour. The samples were left submerged in water for one day. After this period,
the water contained in the beaker was changed and cycle of soaking repeated four
times with change of water between each cycle. Samples were then removed from
water and their dimensions measured to obtain wet volume. Volumetric swelling of
wood samples is calculated with the following formula:
S = [(VW – VD)/ VD] x 100

6
where S is swelling of wood, VW is wet volume of wood, and VD is dry volume
of wood.

8.

Water sorption isotherm

Isotherms were performed using a dynamic gravimetric water sorption
analyzer from Surface Measurement Systems (DVS-Intrinsic) on small teak chips
previously extracted (precise solvent) or non-extracted samples (Simo-Tagne et al.
2016). An initial mass of approximately 10 mg of each sample was used for each
measurement. The sorption cycles applied started from 0% RH at 20°C. Samples
were maintained at a constant RH level until the weight change per minute (dm/dt)
value reached 0.0005% per minute.

9.

Mechanical tests (MOE and MOR)

MOE and MOR were determined with samples of 200 x 20 x 5 mm3 according
to EN 310 by a three point bending device INSTRON 4467 universal testing
machine. MOE (N/mm2) of each sample is calculated with this following formula:
Em = [I13 (F2 – F1)] / [4 b t3 (a2 – a1)]
where I1 is the distance between the centers of support in millimeters, b is the
width of the sample in millimeters, t is the thickness of the sample in millimeters,
F2 – F1 is the increase in load in newton, on the cross section of the loaddeformation curve, F1 should be approximately 10% and F2 approximately 40% of
the breaking load, a2 – a1 is the increase if the arrow at mid-length of the test sample
(corresponding to F2 – F1). MOR (N/mm2) of each sample was calculated with this
following formula:
fm = (3 Fmax I1) / (2 b t2)
where Fmax is the breaking load in newton. Six replicates were used for each
kind of teak wood.

10. Brinell hardness test
This test was conducted according to EN 1534 on the test samples with a
dimension of 200 x 20 x 20 (L, T, R) mm3. The test was performed on each of the
tangential and radial faces of the specimens. The ball diameter is 10 mm; a force
was applied gradually until its value reached 1960 Newton in twenty seconds, this
force was maintained 30 seconds, then slowly discharged. The measure of the
depression showed us the Brinell hardness. The Brinell hardness is then obtained
using the following formula:
HB = 2 F /{ π x D x [D – (D2 – d2)1/2] }

7
where HB is Brinell hardness (N/mm2), F is the nominal force (N), D is the
ball diameter, and d is the diameter of the residual impression (mm).

11.

Contact angle measurements

Contact angle of teak wood was measured by optic method using a Krüss
model DSA10 at room temperature and humidity with water and glycerol as test
liquids. Ten drops of liquid were used for each wood sample. For each drop, eleven
contact angle measurements were performed automatically (one measurement each
two seconds).

12.

Color measurement

Samples were exposed in a QUV accelerated weathering tester from Q-Lab
(USA) for 60 hours. Cycle 1 of ASTM G154-2012 Standard test method “Standard
Practice for operating Fluorescent Ultraviolet (UV) Lamp Apparatus for exposure
of non-metallic Materials” was used. An UV-A 340 lamp was used for the
irradiation at 0.89W/m2/nm to simulate the UV portion of the solar spectrum.
Color changes were analysed using a reflectance spectrophotometer: X-Rite
spectrophotometer. CIEL*a*b* color scale was used. The CIEL*a*b* system is one
of the systems used to quantify color. The L* axis represents the lightness and varies
from 100 (purewhite) to zero (pure black). a* and b* are the chromaticity
coordinates: +a* is for red, −a* for green, +b* for yellow and -b* for blue. Zero (0)
is grey. The overall colour differences (delta E) were calculated using the following
Eq. :
ΔEab*= [(ΔL*)² + (Δa*)² + (Δb*)²]1/2
where ΔL*, Δa* and Δb* are the difference of initial and final values. A low
ΔE* value corresponds to a low colour difference.
13.

Decay durability test

Resistance to decay was evaluated with a method derived from EN 113
standard. In brief, white rot fungi Coriolus versicolor (Cv) and brown rot fungi
Pycnoporus sanguineus (Ps) were inoculated on sterile culture medium prepared
from malt (40 g) and agar (20 g) in distilled water (1 L) in 9cm Petri dishes and
cultivated in an incubator at 22°C temperature and 70% of relative humidity for 7
days. After colonization of all the surface of Petri dishes by the mycelium, three
short rotation or long rotation teak samples or beech samples were put in each petri
dish and then incubated for another 12 weeks. Twelve replicates of sampeles for
each fungus tested. The weight loss (WL) due to degradation by fungus was
calculated with the following equation:
WL = [(M0 – M1) / M0] x 100

8
where WL is the weight loss ratio (%) and M0 and M1 are dry mass of the
samples before and after exposure to fumgus, respectively.

Data Analyzing
Data was analyzed using Microsoft Excel 2010. The research data is displayed
in the form of tables and graphs.

9

3 RESULTS AND DISCUSSION
Extractives Content
Extractives contents were obtained by extraction using successively four
solvents of increasing polarity. The results of extractives contents of short rotation
and long rotation teak wood are presented in Table 1.
Table 1 Extractives content of short rotation and long rotation teak wood obtained
by successive extractions with four solvents of increasing polarity.
Solvent
Dichloromethane
Acetone
Toluene:Ethanol (2:1)
Water
Total

Extractives content (%)
Long rotation teak
Short rotation teak
2.8
0.5
1.1
0.3
1.6
0.4
2.5
2.5
8.0
3.7

Extractives contents of long rotation teak wood (8.0%) was higher than those
of short rotation teak wood (3.7%). The long rotation teak contained more
dichloromethane, acetone, toluene ethanol-soluble extractives content than short
rotation teak did (Table 1), but almost the same in water-soluble extractives (2.5%).
Long rotation teak had higher extractives contents than short rotation teak, this was
due to higher heartwood and mature wood contents in long rotation teak. Darmawan
et al. (2015) reported that long rotation teak has more mature wood and higher
heartwood contents than short rotation teak. Otherwise, short rotation teak has more
juvenile wood and higher sapwood contents. In other studies, it was reported that
extractives contents of heartwood are higher compared to sapwood both for long
rotation and short rotation teak wood (Wijayanto 2014 and Miranda 2011).
However, extractives contents in this study was different from extractives contents
reported by Wijayanto (2014). The extractives contents in heartwood and sapwood
for the long rotation teak (64 years) are 12.65% and 6.84% respectively. Another
result was reported by Miranda et al. (2011), the total extractives contents in
heartwood and sapwood of teak wood (50-70 years) from East Timor are 10.0%
and 9.2%, respectively. Differences extractives contents can be influenced by age
rotation (Lukmandaru and Takahashi 2008), growth location, the type of solvent
and extraction techniques (Moya et al. 2014).
Long rotation teak contained the highest fraction of low polarity compounds
extracted with dichloromethane (2.8%), meanwhile short rotation teak contained
the highest fraction of high polarity compounds extracted with water (2.5%) (Table
2). In addition, Wijayanto (2014) and Miranda et al. (2011) reported that heartwood
contained also more dichloromethane-soluble extractives content (9.06% and 5.7%),
and sapwood contained more water-soluble extractives content (4.78% and 4.4%).
The high nonpolar fraction in heartwood and high polar fraction in sapwood
indicate that the conversion of polar compounds into nonpolar compounds increase

10
during the duramination process in teak wood (Miranda et al. 2011, Niamké et al.
2011, Lukmandaru and Takahashi 2008). Water-soluble extractives content in
sapwood is high because water can dissolve carbohydrates, protein, and tannin
which are high in sapwood. Niamké et al. (2011) reported that high sapwood
extractives contents dissolved in polar solvents caused by the presence of
nonstructural carbohydrates (non-structural carbohydrates (NSC)). NSC in the form
of starch increased dramatically from heartwood to sapwood. Heartwood is
generally have a lower starch content (Fengel and Wegener 1995). High starch
content in wood will contribute negatively to wood durability against wooddestroying organisms. Wood high starch content will be favored by organisms that
utilize starch as food sources.

Chemical Composition
Chemical composition of short rotation and long rotation teak wood extractives
GCMS analysis of extractable with dichloromethane shows that squalene was
the major component for this solvent and for short rotation and long rotation teak
wood (Table 2). Wijayanto (2014) reported the same result for teak wood extracted
with dichloromethane. Windeisen et al. (2003) also reported the same result with
petroleum (nonpolar solvent), and Lukmandaru and Takahashi (2009) which shows
that squalene is the main substance in ethanol-benzene extract.
The dichloromethane, acetone, and toluene-ethanol extracts of long rotation
teak contained anthraquinone (tectoquinone) as the main substance identified with
percentage ranging from 4.5 to 14.5%. It is well known that teak wood extractives
contain dominantly anthraquinones (tectoquinone, 1-hydroxy-2-methylanthraquinone,
2-methyl quinizarin, pachybasin) (Sumthong et al. 2006). The highest percentage of
tectoquinone was in the acetone extract of long rotation teak with percentage 14.5%.
Wijayanto (2014) also reported that tectoquinone is the major component in acetone
extract of long rotation teak (14-28%). Acetone extract had the highest content of
tectoquinone, this indicated that tectoquinone was more easily extracted by aprotic
polar solvent such as acetone. The amount of tectoquinone was very small in the
extract of short rotation teak. It was only found in the acetone extract in the
percentage of 1.5%. This could be due to extractives content of short rotation teak
was lower than the long rotation teak (Table 1) and also different planting site and
age rotation between short rotation and long rotation teak wood. Puteri (2012)
reported that different planting site of teak wood has a strong effect on the content
of tectoquinone in teak wood extractives. It is well known that tectoquinone is the
main compound of teak wood which is considered responsible for natural durability
(Lukmandaru and Ogiyama 2005).

11
Table 2 Major compounds identified by GCMS in the extractives of short rotation
and long rotation teak wood
Long rotation
teak

Retention
time
16.52

Dichloromethane

17.35
21.65
27.01
27.78
11.80
11.99

Acetone

16.68
17.38
17.51
11.88
16.64

Toluene :
Ethanol

16.83
17.51
19.77

Short rotation
teak

Retention
time

Dichloromethane

21.66
27.02
27.72
28.61
27.81
32.52

Acetone

14.62
16.24
17.30
31.87
17.31

Toluene :
Ethanol

19.77
23.41
24.78
31.89

Name of products
4a-Methyl-1-methylene1,2,3,4,4a,9,10,10a-octahydrophenanthrene
9,10-Anthracenedione, 2-methyl(Techtoquinone)
Squalene
Stigmasterol trimethylsilyl ether (Silane)
β-Sitosterol trimethylsilyl ether (Silane)
1,2-Tetradecanediol
5,5-Dimethyl-1-oxa-5-silacyclononanone9
4a-Methyl-1-methylene1,2,3,4,4a,9,10,10a-octahydrophenanthrene
9,10-Anthracenedione, 2-methyl(Techtoquinone)
Cyclononasiloxane, octadecamethyl1,2-Tetradecanediol
Octasiloxane,1,1,3,3,5,5,7,7,9,9,11,11,13,1
3,15,15-hexadecamethylPhenol, 4-tert-butyl-2-phenyl9,10-Anthracenedione, 2-methyl(Techtoquinone)
Cyclooctasioxane, hexadecamethyl-

Match

Percentage
(%)

669

3.5

893

4.5

909
852
794
627

46.7
4.2
9.6
9.3

566

6.1

650

4.6

874

14.5

721
658

5.1
31.5

745

4.0

769

6.4

651

12.8

810

Name of products

Match

Squalene
Stigmasterol trimethylsilyl ether (Silane)
Lanosta-8,24-dien-3-one
Squalene
β-Sitosterol trimethylsilyl ether (Silane)
Benzenepropanoic acid, 3,5-bis(1,1dimethylethyl)-4-hydroxy-, octadecyl ester
1-Nonadecene
1-Nonadecene
Trisiloxane, octamethyl4-tert-Butylcalix[4]arene
2-tert-Butyl-6-methylphenol, trimethylsilyl
ether
Linoleic acid, 2,3-bis-(O-TMS)-propyl
ester
Oxirane, [(hexadecyloxy)methyl]Oxirane, [(hexadecyloxy)methyl]2 β,4a-Epoxymethylphenanthrene-7methanol

909
845
467
758
732

5.9
Percentage
(%)
23.3
6.5
5.5
7.1
15.1

613

30.0

922
922
595
468

10.6
8.2
5.4
4.8

607

4.1

561

6.1

-

12.7
5.6

482

8.9

12
Chemical composition of short rotation and long rotation teak wood
The chemical composition of short rotation and long rotation teak wood is
shown in Table 3.
Table 3 Holocellulose, cellulose, hemicellulose, and lignin Klason of short rotation
and long rotation teak wood

Holocellulose (%)
Cellulose (%)
Hemicellulose (%)
Lignin Klason (%)

Long rotation teak
68.53
49.18
19.35
32.19

Short rotation teak
67.50
48.80
18.70
35.53

Long rotation teak (less juvenile wood and more heartwood contents)
contained more holocellulose, cellulose, and hemicellulose contents and lower
lignin content compared to short rotation teak (more juvenile wood and lower
heartwood content). However, the chemical composition of short rotation teak was
not remarkably different compared to long rotation teak (Table 3). Differences in
chemical composition between short rotation and long rotation teak can be
influenced by many factors such as location where teak grows, climate, and its
location in the wood (Dumanauw 1990). Another result reported by Miranda et al.
(2011), holocellulose and cellulose contents in heartwood of 50-70 years teak wood
(holocellulose 57.5% and cellulose 44.6%) from East Timor was higher than
sapwood (holocellulose 56.2% and cellulose 43.7%), but their lignin contents was
relatively the same (32.2% in heartwood and 32.4% in sapwood). According to
Fengel and Wegener (1995), in general, sapwood contains more lignin compared to
heartwood. Thomas (1984), Kininmonth (1986), and Zobel and Sprague (1998)
stated that juvenile wood has higher lignin and lower cellulose content.

Density
The density of long rotation teak was 664 kg/m³, while short rotation teak
was 472 kg/m³. The results show that long rotation teak had a greater density than
short rotation teak. Martawijaya et al. (2005) found the density of long rotation teak
to range from 620–750 kg/m³ with an average of 670 kg/m³. Darmawan et al. (2015)
also reported the density of short rotation and long rotation teak wood to range 443535 kg/m³ and 635-714 kg/m³ respectively with the average density for short
rotation and long rotation teak wood of 486 kg/m³ and 670 kg/m³ respectively.
Results in this work indicate that the density of short rotation and long rotation teaks
are within the range reported in that literature. Pérez (2005) and Moya and Ledezma
(2003) concluded that wood density is more related to tree age than to silvicultural
management, site, or region, especially in the early plantation stages.

13
Microscopic Wood Anatomy
Vessel frequency in cross section was classified according to the number of
vessels per mm². There is a different value in the frequency of vessel cell between
long rotation and short rotation teak wood. Long rotation teak wood had a lower
vessel frequency values (average 4.2 vessels/mm²) compared to short rotation teak
wood (average 5.5 vessels/mm²). Martawijaya et al. (2005) found the vessel
frequency of long rotation teak wood in the range from 3-7 vessels per mm². Utomo
(2012) also found the vessel frequency of long rotation teak wood in the range 4-8
vessels per mm². This vessel frequency value is one of important factors which
could determine the dimensional stability and wettability of teak wood that affect
the quality of wood.
A

B

Figure 2 Transverse section of long rotation (A) and short rotation teak wood (B)
The porosity average value of both short rotation teak and long rotation teak
wood were 45.28 ± 2.5 % area and 36.21 ± 1.8 % area, respectively. The values of
porosity showed the proportion of voids in the growth ring of the wood. Long
rotation teak wood had a lower porosity compared to short rotation teak wood.
Percentage of porosity can affect to mechanical properties of wood. High porosity
of wood tends to reduce strength.

Swelling
The volumetric swelling for long rotation and short rotation teak wood is
presented in Figure 3. The mean values of swelling for long rotation and short
rotation teak wood were 7.2% and 8.4% respectively. These results indicate that the
long rotation teak with higher density, lower vessel frequency, and lower porosity
would have a lower volumetric swelling than short rotation teak, which leads to
improved dimensional stability. The higher volumetric swelling for the short
rotation teak suggests that careful attention should be given for the use of short
rotation teak in some wood-processing technologies (e.g. production of sawn timber
and drying, plywood, LVL).

Volumetric Swelling (%)

14

10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0

Long rotation teak
Short rotation teak

1

2

3

4

5

6

Replicates

Figure 3 Dimensional stability of short rotation and long rotation teak wood
These results also show that the long rotation teak with higher extractives
contents affected wood increasing stability. Miller 1999 stated that extractives
contents may also affect wood increasing stability in changing moisture conditions
and increasing weight slightly. High extractives contents cause a decrease in the
hygroscopic properties of some species of wood, therefore this may be one of the
factors that led to an increase in the dimensional stability of wood (Skaar 1972).
According to Haygreen and Bowyer (2003), extractives content in the wood can
affect wood permeability, level of ease of water into the wood.

Water Sorption Isotherm
The full sorption–desorption isotherm is presented in Figure 4 for short
rotation and long rotation teak wood. Sorption–desorption isotherms were obtained
for 4 different samples: long rotation teak wood with and without extractives; short
rotation teak wood with and without extractives. Figure 4 shows the change in mass
values in sorption and desorption for the short rotation and long rotation teak wood
at 20˚ C.
The sorption curves were higher than the desorption curves for any type of
samples. For any given water activity, the change in mass of the samples increased
as the relative humidity increased. The change in mass values of the long rotation
teak wood, either sorption or desorption, were slightly lower than the short rotation
teak wood values. This indicate that long rotation teak has higher stability in change
in mass compare to short rotation teak due to lower vessel frequency and porosity
in long rotation teak. Lower vessel frequency and porosity of teak wood increased
its stability in either sorption and desorption and decreased hygroscopicity.

15
20.00

Long rotation teak Sorption

18.00

Long rotation teak Desorption

Change in mass (%) - Ref

16.00

Long rotation teak (without
extractives) Sorption
Long rotation teak (without
extractives) Desorption
Short rotation teak Sorption

14.00
12.00
10.00
8.00

Short rotation teak Desorption

6.00
Short rotation teak (without
extractives) Sorption
Short rotation teak (without
extractives) Desorption

4.00
2.00
0.00
-2.00 0.0

50.0

100.0

Sample RH (%)

Figure 4 Sorption and desorption isotherm of short rotation and long rotation teak
wood at 20˚ C
These results also show that the teak samples without extractives (extracted)
had a greater change in mass values than the samples with extractives. These results
indicate that the existence of extractives in wood effected change in mass values.
Various studies have shown that the extractives content has a role in the sorption
process, as wood with extractives has lower EMC and lower change in mass
(Wangaard and Granados 1967; Hernandez 2007).

MOE and MOR
Mean MOE values for long rotation and short rotation teak wood calculated
in this study were 12861.8 N/mm² and 9929.3 N/mm², respectively, and their mean
MOR values were 118.9 N/mm² and 97 N/mm², respectively (Figure 5). Darmawan
et al. (2015) found that the mean MOE values for long rotation teak and short
rotation teak wood are 12759 N/mm² and 8323 N/mm², respectively, and their mean
MOR values are 102 N/mm² and 77 N/mm², respectively. Martawijaya et al. (2005)
also found that the MOE and MOR of long rotation teak are 12514 N/mm² and 101
N/mm², respectively. The MOE and MOR values of short rotation teak wood in this
study were lower than those of the long rotation teak wood. Concerning wood
properties, juvenile core is reported to be of lower density, lower stiffness (MOE)
and strength (MOR), higher grain angle, higher longitudinal shrinkage, higher
incidence of reaction wood (Evans et al. 2000; Koubaa et al. 2005; Clark et al.
2006; Adamopoulus et al. 2007; Gryc et al. 2011; Lachenbruch et al. 2011).
Miranda et al. (2011) reported that the mean MOE and MOR values of teak wood
(50-70 years old) from East Timor are 10684 N/mm² and 141 N/mm², respectively.
Several authors have also found that differences in mechanical and physical
properties of juvenile wood and mature wood in teak were negligible (Baillères and
Durand 2000). Kokutse et al. (2004) also reported that MOE value for 70 years teak

16
is 16704 N/mm². The lower MOE and MOR suggest that careful attention should
also be given for the use of short rotation teak for construction purposes.
14000.0

140.0

12861.8

12000.0

120.0

118.9

MOR (N/mm²)

MOE (N/mm²)

9929.3
10000.0
8000.0
6000.0
4000.0
2000.0

97.4

100.0
80.0
60.0
40.0
20.0

0.0

0.0
Long rotation Short rotation
teak
teak

Long rotation teak

Short rotation teak

Long rotation Short rotation
teak
teak
Long rotation teak

Short rotation teak

Figure 5 MOE and MOR of short rotation and long rotation teak wood
Although the short rotation teak had lower MOE and MOR values, however
its values are greater than others fast growing species such as Jabon (MOE 6668
N/mm²; MOR 67.7 N/mm²) (Martawijaya et al. 1989) and Sungkai (MOE 8237
N/mm²; MOR 55.7 N/mm²) (Martawijaya et al. 2005). This indicate that the
utilization of short rotation teak in Indonesia is still appropriate for some indoor
applications.
Brinell Hardness
The results of Brinell hardness test for short rotation and long rotation teak
wood are shown in Figure 6. Values presented were the average on radial and
tangential penetrations. Long rotation teak wood had a greater Brinell hardness
mean values than short rotation teak wood (35.2 N/mm² and 27.9 N/mm²,
respectively). Martawijaya et al. (2005) found that the Brinell hardness mean value
of long rotation teak was 41.3 N/mm². Wahyudi et al. (2014) also found that the
Brinell hardness mean values of short rotation teak in 4 years old was 20.8 N/mm².

17

Brinell Hardness (N/mm²)

40.0

34.8

35.6

35.0
27.7

30.0

28.1

25.0
20.0

Tangential

15.0

Radial

10.0
5.0
0.0
Long rotation teak

Short rotation teak

Figure 6 Brinell hardness of short rotation and long rotation teak wood
The greater Brinell hardness values of long rotation teak wood were due to
the higher density of long rotation teak wood than short rotation teak wood. The
wood with high density indicating that the mass of wood is denser than that wood
with low density. Dwianto and Marsoem (2008) reported that density of wood is
one of the important physical properties of wood that can affect the mechanical
properties such as MOE, MOR and hardness.

Wettability
Contact angles for long rotation and short rotation teak wood are presented in
Figure 7(a) and 7(b). Contact angle is one of the parameters generally used to define
wettability (Walinder 2000; Bryne and Walinder 2010). Contact angle value was
used in this study to investigate the wettability. In this study, water and glycerol
were used for measurement of contact angle for long rotation and short rotation teak
with and without extractives.
Figure 7(a) shows that contact angle using water as liquid was greater for long
rotation teak with and without extractives compared to short rotation teak. There
was a great difference for the initial and final contact angles measured for long
rotation and short rotation teak. Due to the high water permeability of short rotation
teak, the contact angle on its surface decreased rapidly with time. Contact angles
for water on the surface of short rotation teak with and without extractives were
13.2° and 4.4˚ at the beginning (t= 0 s), respectively, then the contact angles were
observed to be 0° both for short rotation teak with and without extractives at t= 19
s. Otherwise, the contact angle of water on the surface of long rotation teak was
prominently larger from beginning (t= 0 s) up to end (t= 19 s) compared to the
contact angle of the short rotation teak.
Figure 7(b) also shows that relatively the same tendency of contact angle was
generated by glycerol liquid in the surface of long rotation and short rotation teak.
Long rotation teak with extractives had the greatest contact angle value, followed
by short rotation teak with extractives, long rotation teak without extractives, and
short rotation teak without extractives. However, there was no great changes of
contact angles from initial to final contact measured on both the surface of long

18

120.0

120.0

100.0

100.0

Contact Angle= θ ˚

Contact Angle= θ ˚

rotation and short rotation teak. The small changes in contact angle of the glycerol
on the surface of teak wood compared to water indicate that the distribution and
penetration of glycerol were very slow. This is due to glycerol had a higher viscosity
compared to water. In addition, surface tension of glycerol is lower (64.00 mN/m)
compared to surface of water (72.80 mN/m) (Kaelble 1971; Wu et al. 1995). There
are also many factors (such as surface tension phenomena and viscosity of liquids)
that influence penetration (Huang et al. 2012). Gavrilovic-Grmusa et al. (2012)
stated that the properties of the coatings (e.g., viscosity, type of coating, temperature,
and surface tension) also influence the wettability.

80.0
60.0
40.0
20.0

80.0
60.0
40.0
20.0
0.0

0.0
0 2 4 6 8 10 12 14 16 18 19

0 2 4 6 8 10 12 14 16 18 19

Time= t (second)

Time= t (second)

Long rotation teak

Long rotation teak

Long rotation teak (Without
extractives)
Short rotation teak

Long rotation teak (Without
extractives)
Short rotation teak

Short rotation teak (Without
extractives)

Short rotation teak (Without
extractives)

(a)

(b)

Figure 7 Contact angle of short rotation and long rotation teak wood using water (a)
and glycerol (b) as liquid
The results in figure 7 show that teak wood without extractives had lower
contact angle (better wettability) compared to teak wood with extractives. Higher
contact angle for the wood with extractives is considered to be caused by higher
hydrophobicity on the surface of the long rotation teak compared to short rotation
teak as the long rotation teak contained higher fractions of low polarity compounds
extracted with dichloromethane (2.8%) (Table 1). Low polarity compounds of
extractives such as fats, wax, and resin tend to be hydrophobic, therefore its
presence in the wood will reduce the ability on spreading and penetration of liquids
into the wood surface.
These results also indicate that short rotation teak had lower contact angle
(better wettability) compared to long rotation teak. This is due to the short rotation
teak had a lower extractives content compare to long rotation teak (Table 1).
Extractives in wood inhibited the liquids into the wood. According to Uprichard
(1993); Ghofrani et al. (2016); and Hakkou et al. (2005) amount of extractives affect

19
the wettability of wood surfaces and thereby the application of paints and adhesives.
Besides that, the effect of wood species on the spreading and penetration could
strongly depend on the texture and structure of the wood surfa