eJournal MAPEKI (Masyarakat Peneliti Kayu Indonesia)
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Inter-tree Variation in Chemical Components of North Sumatra Benzoin Gum (Styrax sp.)
No full textBenzoin gum, which is known as Sumatra benzoin (Styrax sp), is widely used as an ingredient in the incense. Although these resins are widely used as flavours and fragrances, no studies have been made on inter-tree variation of its chemical composition. Therefore, benzoin gum samples were tapped from the 30 individual trees (age 10 years, 9~35 cm in diameter) grown in the community forest of Polung, Humbang Hasundutan Regency, North Sumatra. The gum chemical components were analyzed by GC-MS and identified by comparing the fragmentation pattern with the standard components and literature studies. It was found that the major compounds detected by GC-MS were cinnamic acid (51.48%), cinnamyl cinnamate (62.56%), benzoic acid (1.94%), chavicol (5.18%), benzyl cinnamic acid (7.8%), atropic acid (9.84%), and vanillin (1.47%). Two main constituents that were always detected from 30 benzoin trees were chavicol and cinnamic acid, followed by cinnamyl cinnamate (28 trees) and benzoic acid (14 trees). By cluster analysis, 30 samples of benzoin gum can be classified into clusters I - III based on the average chemical components. Cluster I consisted of 7 individual trees with a higher percentage of benzoic acid and chavicol but lower concentration of cinnamic acid compared to other clusters. Cluster II consisted of 18 individual trees with a high percentage of cinnamyl cinnamate whereas clusters III consisted of 5 individual trees characterized with a high percentage of cinnamic acid. By Pearson correlation, it was observed that no significant correlation between the values of diameter and the amount of chemical components of benzoin gum
Ultraviolet Shielding Performance of Coconut Coir as a Filler in Low-Density Polyethylene (LDPE) Plastic Mulch
No full textPlastic mulch is a layer of material applied to the soil surface to maintain moisture retention in the soil by preventing evaporation, reduce weed growth by blocking sunlight from reaching underlying weeds, and optimize fertilizer use by minimizing nutrient loss to the environment. However, the degradation of low-density polyethylene (LDPE), a thermoplastic commonly used for mulching, into microplastics due to exposure to UV radiation. This research explored the potential of coconut coir, a natural fiber with a high lignin content ranging from 30 to 46%, as a UV protective agent. The objective was to develop biodegradable plastic-based mulch composites that have better resistance to UV exposure by incorporating coir as a filler material in LDPE-based composites. Different ratios of coconut fiber were used (10%, 20%, 30%, and 40%), and Maleic anhydride grafted polyethylene (PE-g-MAH) was used as a binder at 2% of total weight mixed with LDPE in a rheomixer (80 rpm, 120°C for 10 min). The resulting plastic mulch bio-composites were evaluated for thermal, mechanical, UV resistance, and biodegradability properties. The results showed that the higher addition of coconut coir resulted in a decrease in the thermal and mechanical characteristics of the composite. However, the addition of higher coconut coir in the composite at 40% can provide an increase in the composite's resistance to ultraviolet light exposure, and the properties are easily degraded by the environment (biodegradable).
Relationship Between Wood Properties and Drying Qualities at Three Age Groups of Mindi (Melia azedarah L) Tree for Furnitur Materials
No full textAll wood based products should have been dried to ensure their stable dimension. Indicators of stable dimension can be figured-out from wood physical properties, especially ratio of tangensial shrinkage to radial shrinkage (T/R ratio) and wood drying properties at high temperature. From those two indicators could be predicted the drying quality of wood as a basic to determine minimum – maximum of drying temperature. This research aimed to look-into the relationship between wood properties of wood and drying quality of mindi (Melia azedarach L)wood at their 5, 9, and 13 year-old trees. The preparing of test samples, and testing methods on wood physical properties covered moisture content, air-dry density, and shrinkage in tangential and radial direction, which referred to the BS 1957. Meanwhile, drying properties followed the modified Terazawa’s method. Five classes of wood drying qualities could be derived from the analysis of T/R ratio and drying property at each tree age group. Results revealed that wood density ranged about 0.46 – 0.58 g/cm3. Drying quality of each wood (except the portion near the pith) belong to B (good) for 13 years old, C (fair) for 9 years, and D (poor) for 5 years old. Related to the drying quality, the minimum – maximum temperature for 13 years mindi wood was 55–85 oC; for 9 years was 50–80 oC; and for 5 years was 40–65 oC. Supported by the performance of wood surface, especially at 13 years old, mindi wood was suitable for wooden furniture
Alkaline Pulping of Red Meranti (Shorea selanica Blume)
No full textThe suitability for papermaking of red meranti (Shorea selanica Blume) wood for three alkaline pulping processes i.e soda, soda-anthraquinone (AQ), and kraft was studied. The fiber morphology and chemical properties were also examined. Cooks were made for 20% (as Na2O) activate alkali. The resulting pulp and paper properties were investigated. The basic density of red meranti was 0.42 g/cm3 and can be classified to be of medium density. The fibre proportion (67.14%) and fibre length (1.07 mm) of red meranti in this study were within the range of tropical hardwoods. The derived values for Runkel ratio, slender ratio, and flexibility coefficient were 0.54, 54.93, and 0.62, respectively. Furthermore, total extractives, lignin, and cellulose contents as well as solubility in 1% NaOH were 5.17%, 31.05%, 45.20%, and 26.02%, respectively. The alkaline pulps showed low kappa number (16~22) and reject level (0.5~1.5%) with the best results for screened yield (47.41%) being achieved in soda pulping. With regard to strength and optical properties of the paper hand-sheets, soda-AQ pulping showed the highest value in burst index (2.36 KPa m2/g), tear index (8.47 + 1.13 mNm2/g), and brightness (19.81%), whereas kraft pulping gave the best result in tensile index (28.39 Nm/g). The comparatively low values of yield and strength properties in kraft pulping might be due to overcooking in this experiment
Prediction of Density in Standing Trees of Various Wood Species in Natural Forests Using Near-infrared Spectroscopy
No full textDensity plays an important role as basic information for applying wood as construction materials. Recent years, the application of near-infrared spectroscopy as non-destructive testing (NDT) has been promising. Density prediction for standing trees in huge variation trees and species of natural forest needs to be investigated using NDT as of eco-green harvesting. The combination of density information and near-infrared spectroscopy is enabled to build a prediction model. This research applied increment cores sampling for density prediction analysis using near-infrared spectroscopy method. The research combined increment cores samples from multiple wood species to be analyzed in one chemometrics analysis of cross-validation partial least squares regression (CV-PLSR) to build a prediction model of density. The research resulted coefficient of determination for cross-validation (R2CV) of 0.76 with number of latent variable (LV) 10 from the 1st derivative with 13 smoothing-point spectra and wavelength of 1200 – 1800 nm as the best prediction model. The result seemed sufficient enough with those number of LV for this small tube wood sampling of increment cores from multiple wood species. This research proved that building a prediction model for multiple wood species is possible to be done
Chemical investigation of methanol extracts of Swietenia mahagoni leaves and its antioxidant activity
No full textSwietenia mahagoni is among the species of trees used by the Indonesian Government for the purpose of afforestation and timber production through Perhutani Enterprise. The common use of this species as wood products has prompted investigating the chemical properties of its leaves. Based on this background, this study aimed at investigating the methanol extracts of both 2- and 3-year old S. mahagoni leaves extractives together with its antioxidants and phenols contents. The antioxidant activity was conducted through the DPPH (1,1-diphenyl-2-picrylhydrazyl) method, while the total phenolic and flavonoid content were measured through Folin-Ciocalteu and AlCl3 methods, respectively. Additionally, 24 compounds were characterized by the GC-MS, and were grouped into phenolics, fatty acids and hydrocarbons, and terpenoids. The total phenolic and flavonoid contents in both 2 and 3 years old leaves of S. mahagoni ranged from 36.4 ± 0.84 to 42.0 ± 0.18 mg GAE/g dried extract and from 2.24 ± 0.15 to 18.55 ± 1.05mg QE/g dried extract, respectively. Also, the antioxidant values were 66.45 ± 1.85% and 77.59 ±11.23%, respectively. Based on the results, the antioxidant activity of S. mahagoni leaves was indicated as a result of the presence of α-tocopherol and α-tocopherolquinone in the leaves extracts
Chemical Properties of “Jati Unggul Nusantara” Teak Wood from Gunungkidul
No full textJati Unggul Nusantara (JUN) trees show a fast-growing characteristic and a possibility to be harvested in short rotation. This study aims to determine the chemical properties of 8-year-old JUN tree parts. Three individual trees were felled from Paliyan, Gunungkidu, Yogyakarta, Indonesia. The tree parts were observed vertically (i.e., the bottom, center, top, branches, and twigs) and radially (i.e., sapwood and heartwood of the trunk). The result showed that the average content of cell wall components of extractive-free wood, i.e., hemicellulose, α-cellulose, and lignin, were 20.38~25.71%, 41.88~49.10%, and 26.46~29.85%, respectively. Furthermore, successive extractive measurements showed that ethanol-toluene and hot-water soluble extracts (based on dry wood) were at the levels of 3.01~7.58% and 1.85~3.09%, respectively. The ash content, silica content, and pH values were 0.48~0.82%, 0.13~0.37%, and 5.89~7.51%, respectively. By an analysis of variance, significant differences between the sapwood and the heartwood were observed in ethanol-toluene extractive, lignin, holocellulose, and cellulose contents. The differences among tree parts did not show any significant effect on the hot-water soluble content. Significant differences between the main stem and branches or between the main stem and twigs were observed in most chemical properties
The Effect of Ultrasonication and Delignification Treatment on the Sugar Released Value of Wood
No full textThe objective of these research was to study the impact of ultrasonication and delignification pretreatments in several wood species on their easiness for enzymatic hydrolysis, having the potential to be developed as the feedstocks for bioethanol production. Four different wood species from three botanical gardens in Indonesia have been selected, i.e., Gymnostoma sumatranum, Firmiana malayana, Pterocarpus indicus, and Alstonia scholaris, due to their higher sugar released values than a fast-grown tree, Sengon (Paraserianthes falcataria), when all were directly enzymatically hydrolyzed without pretreatment. The sugar released values after ultrasonication and enzymatic hydrolysis were between 3 – 5.5 mg/100 mg wood meal. When delignification pretreatment was performed, the sugar released values were higher than those with ultrasonication, ranging between 4 – 10.2 mg/100 mg wood meal. All the sugar released values after pretreatment were higher than those without pretreatment. Gymnostoma sumatranum was selected as the most potential wood species in this study due to its consistency among the species producing highest sugar released across different treatments. The SEM results showed that there was no significant changes in the morphological structure of the untreated fiber before and after enzymatic saccharification since it still had a complex structure due to the high lignin content. However, after the delignification treatment, the surface morphology of the fiber showed a decrease in the number of pits of the fiber, the surface residual of pits were reduced, parallel lines were more clearly visible, and the fiber structure was damaged with more small holes presented. The surface morphology of the fiber from the wood powder having delignification pretreatment supports the sugar released values which shows that the these values were higher than other treatments due to more recalcitrant substances were degraded, making it was easier for enzymes to break down cellulose. After ultrasonication, the SEM result showed less disrupted cell wall compared to after delignification which confirmed the higher sugar released data with delignification
Effect of Maleic Acid and Glycerol Concentrations on the Characteristics of Glycerol Ester of Maleic Rosin
No full textGum rosin, distilled from the resin of pine trees (Pinus merkusii), is highly susceptible to degradation and oxidation. To maintain its quality, modification by fortification, among other methods, should be made, where a stable product named glycerol ester of maleic rosin (GEMR) is produced. In the experiment reported in this paper, rosin was prepared on the laboratory scale. Fortification was performed using maleic acid of varied concentrations (8%, 10%, and 12%, w/w), followed by mixing with glycerol through an esterification process (10%, 12%, and 14%, w/w). The average yield of GEMR produced was in the range from 67.11% to 79.30%. The average softening point, acid number, and ash content were in the ranges of 91.67–120.67°C, 5.84–9.82 mg KOH/g, and 5 x 10-3–14.7 x 10-3%, respectively. No significant effect of concentration was observed on yield and acid number. The GEMR product was completely soluble in toluene at all concentration levels. It was found that the increase of glycerol portion affected the properties of GEMR, i.e., lower ash content and acid number, while higher softening point. Based on the acid number, solubility in toluene, and softening point values, the GEMR obtained in this research fulfilled the requirements of Chinese GEMR standards
A Review: The Soluble Sugars Involved in The Process of Heartwood Formation
No full textThis study aims to examine the soluble sugars involved in the process of heartwood formation using 87 journal articles and non-articles. The data used was collected through an online search with 5 keywords, namely “heartwood formation”, “reserve material of heartwood”, “non-structural carbohydrate of heartwood”, “starch of heartwood” and “sucrose of heartwood”. By removing irrelevant papers, 44 suitable journal articles and non-articles were found. Studies showed that monosaccharide fraction was the largest group compared to the other fractions as well as dominated by the hexose group. In addition, several species such as Swietenia mahagoni, Pinus sylvestris, Betula pendula, and Fagus sylvatica were detected more complete than other species in the fraction of soluble sugars (monosaccharides, disaccharides, trisaccharides, tetrasaccharides, alditol, and cyclitol). Based on previous studies, the contents of glucose and sucrose compounds were the major compound and plays an important role in storing energy reserves and the process of heartwood formation. Meanwhile, the levels of arabinose and galactose were the minor components in several species. Within tree variation, soluble sugars drop from the sapwood to the heartwood and from the top to the bottom of the tree. Subsequently, the alditols and cyclitols fractions need special issues, especially for tropical species related to their role