Color and chemical characterization of partially black-streaked heart-wood in teak (Tectona grandis)

Abstract

The heartwood of teak in certain areas of Java Island displays irregular black streaks along the annual rings. We investigated the color and chemical characteristics in a radial direction of partially black-streaked heartwood samples. Color properties (pH value, inorganic element, extractive content and extractive characterization) were measured in the color co-ordinates CIELAB system. The results show that the black streak part was 12–15 brightness (L*) value units less than the normal heartwood. Furthermore, the black streak part had more red (a*) but less yellow (b*), hue (h) and chroma (C*) than the normal wood. The pH value, ash content and calcium contents of the black streak part were slightly higher than those obtained for the normal wood. The content of the low-polar extractive (n-hexane and ethyl acetate) of the black streak part was considerably higher than that for the normal wood. The blackening process was speculated to be a kind of defense mechanism indicated by remarkable amount of bioactive compound called tectoquinone.

Keywords

Tectona grandis / black streak / extractives / inorganic materials

References

[1] ASTM D1102. 1981. Standard test method for ash in wood. Annual Book of ASTM Standards. 1916 race St., Philadelpia, Pa. 19103: American Society for Testing and Materials, pp360–361.

[2] ASTM D1110. 1981. Standard test methods for water solubility of wood. Annual Book of ASTM Standards. 1916 race St., Philadelpia, Pa. 19103: American Society for Testing and Materials, pp378–379.

[3] Haupt M., Leithoff H., Meier D., Puls J., Richter H.G., Faix O.. Heartwood natural durability of plantation-grown teakwood (Tectona grandis L.)—a case study. Holz Roh-Werkst, 2003, 61: 473-474.

[4] Kubo T., Ataka S.. Blackening of sugi (Cryptomeria japonica D. Don) heartwood in relation to metal content and moisture content. J Wood Sci, 1998, 44: 137-141.

[5] Lemos T.G., Costa S.M., Pessoa O.L., Braz-Filho R.. Total assignment of ¹H and ¹³C NMR spectra of tectol and tecomaquinone. Magn Reson Chem, 1999, 37: 908-911.

[6] Lukmandaru G., Takahashi K.. Variation in the natural termite resistance of teak (Tectona grandis Linn fil.) wood as a function of tree age. Ann For Sci, 2008, 65 708

[7] Minato K., Morita T.. Blackening of Diospyros genus xylem in connection with boron content. J Wood Sci, 2005, 51: 659-662.

[8] Narayanamurti D., George J., Pant H.C., Singh J.. Extractives in teak. Sylvae Genet, 1962, 11: 57-63.

[9] Noda E., Aoki T., Minato K.. Physical and chemical characteristics of the blackened portion in Japanese persimmon (Diospyros kaki). J Wood Sci, 2002, 48: 245-249.

[10] Perry N.B., Blunt J.W., Munro M.H.G.. A cytotoxic and antifungal 1,4 naphtaquinone and related compounds from a New Zealand brown alga, Landsburgia quercifolia. J of Nat Prod, 1991, 54: 978-985.

[11] Rudman P., Da Costa E.W.B., Gay F.J., Wetherly A.H.. Relationship of tectoquinone to durability in Tectona grandis. Nature, 1958, 181: 721-722.

[12] Sandermann W., Dietrichs H.H.. Chemische untersuchungen an Teakholz. Holzforschung, 1959, 13: 137-148.

[13] Sandermann W., Rothkamm M.. The determination of pH values of woods and their practical importance. Holz Roh Werkst, 1959, 17: 433-440.

[14] Sandermann W., Simatupang M.H.. On the chemistry and biochemistry of teakwood (Tectona grandis L. fil). Holz Roh-Werkst, 1966, 24: 190-204.

[15] Shigo A.L.. Compartementalization of discolored and decayed wood in trees. Material und Organismen, 1976, 3: 221-226.

[16] Starck M., Bauch J., Simatupang M.H.. Characteristics of normal and discoloured wood of Ilomba (Pycnanthus angolensis Exell). Wood Sci Tech, 1984, 18: 243-253.

[17] Suhaendi H. 1998. Teak improvement in Indonesia. In: M. Kashio and K. White (eds), Teak for the Future. Proceedings of the Second Regional Seminar on Teak. Yangon, Myanmar. 29 May–3 June 1995. RAP Publication 1998/5 TEAKNET Publication No. 1. Yangon, Myanmar: FAO Regional Office for Asia and the Pacific Bangkok, Thailand, pp179–188.

[18] Takahashi K.. Relationships between the blackening phenomenon and norlignans of sugi (Cryptomeria japonica D. Don) heartwood. I. A case of partially black-heartwood. Mokuzai Gakkaishi, 1996, 42: 1119-1125.

[19] Windeisen E., Klassen A., Wegener G.. On the chemical characterization of plantation teakwood (Tectona grandis L.) from Panama. Holz Roh-Werkst, 2003, 61: 416-418.

[20] Yasue M., Ogiyama K., Ichinei J.. Extractive components in black portion of Japanese persimmon. Proceedings of the 25th Annual Meeting of the Japan Wood Research Society. 1975, 1-1-17 Mukogaoka, Bunkyo-ku, Tokyo 113-0023: The Japan Wood Research Society, 180.