Ganis Lukmandaru’s research while affiliated with Universitas Gadjah Mada and other places

Clonal Acacia hybrid (Acacia mangium × Acacia auriculiformis) breeding in Indonesia aims to improve wood quality for the paper industry. This study investigated the effect of anthraquinone (AQ) addition on the quality of pulp and paper from ten-year-old clonal Acacia hybrid (015D) wood. Pulp making was carried out by kraft process with an active alkali concentration of 17%, sulfidity of 25%, and AQ concentrations of 0%, 0.05%, and 0.10% at a maximum temperature of 170oC for two hours of cooking time. AQ addition increased the yield to 54.70%, 58.23%, and 59.14% and decreased the kappa number to 24.06, 20.30, and 16.87, respectively. In terms of physical and optical properties, the paper had a burst index ranging from 3.31 to 3.66 kPa·m²/g, a tear index ranging from 1.72 to 2.40 mN·m²/g, a tensile index ranging from 49.41 to 50.28 Nm/g, opacity ranging from 87.38% to 88.44%, and brightness degrees ranging from 24.18 to 25.78. Burst and tensile indices met the Indonesian National Standard for broadleaf wood. AQ at 0.05% to 0.10% significantly reduced kappa numbers but did not significantly affect yield, mechanical, or optical properties. Therefore, an AQ concentration of 0.05% is recommended for clonal Acacia hybrid wood

Jabon (Anthocephalus spp.) is a fast-growing species with considerable potential for pulp and paper production in Indonesia. This study aims to determine the chemical component in wood and bark of 10-year-old Anthocephalus cadamba (families 23, 11, and 6) and 5-year-old Anthocephalus macrophyllus (families 75, 85, and 2) in the bottom part of the trees. The results showed that chemical properties of A. cadamba in the wood and bark, i.e., holocellulose, α-cellulose, hemicellulose, and Klason lignin content ranged from 62.66 to 75.75%, 32.42 to 48.43%, 26.72 to 34.42%, and 22.80 to 35.10%, respectively. The levels of holocellulose and α-cellulose in these species are in the high class. High holocellulose and cellulose content indicates high pulp yield, which will benefit the pulp and paper industry, especially F6 and F2.

Sengon is a fast-growing wood species widely distributed on Java Island and commonly utilised for plywood production. It is frequently subjected to boiling treatment to reduce veneer defects, making it important to understand how this treatment affects its properties. This study investigated the effect of boiling treatment on the properties of sengon wood, involving three seven-year-old trees which were subjected to a control and an experimental treatment at 80℃ for ten hours. The wood specimens were divided into near-pith, middle, and near-bark sections. The specimens were powdered to a size of 40–60 mesh for successive extraction with n-hexane, methanol, and hot water. The total phenolic content was measured from the methanol-soluble extract, and the total polysaccharide content was measured from the hot-water-soluble extract. Chemical components such as holocellulose, alpha-cellulose, hemicellulose, lignin, ash, and silica contents, as well as pH values, were determined. T-test revealed that boiling treatment significantly reduced extractive levels (in ethanol-toluene and methanol solubles) but significantly increased total phenolic and polysaccharide contents. No significant effect was observed on cell wall chemical components. One-way ANOVA indicated that the radial direction significantly affected methanol-soluble extractive content, total phenolic content, and total polysaccharide content.

Both wood and non-wood industries generate large amounts of residues from processes like bark peeling and removal. In the cajuput oil industry, the waste products include distillation residues and cajuput bark. The diverse extractives and chemical components found in cajuput bark have the potential for enhanced value through various applications. This study aimed to determine the chemical components, extractive content (EC), and percentage inhibition of antioxidant activity (%IAA) of cajuput bark extract to explore more effective uses of this byproduct. Cajuput bark (Melaleuca cajuputi Powell) was sourced from a 26-year-old cajuput stand in Paliyan, Gunungkidul. The bark powder was extracted using a methanol-water solvent mixture at concentrations of 40% and 80%. Extraction was conducted in water baths at temperatures of 60°C and 100°C for 120 minutes. GC-MS identified several chemical components in the methanol extract of cajuput bark, including sugars (erythritol, D-arabinose, D-lyxose, adonitol, d-galactose, D-glucitol, and L-rhamnose), fatty acids (lactic acid, glycerol, glyceric acid, malic acid, and palmitic acid), and phenolic derivatives (gallic acid and protocatechuic acid). The average extractive content of the methanol extract of cajuput bark was 4.07%, and the percentage inhibition of antioxidant activity was 40.26%.

Background: Efforts to enhance the genetic quality of Eucalyptus pellita F. Muell by PT. Riau Andalan Pulp and Paper included breeding several clones to optimize raw materials for pulp and paper production. Three clones—CEP06, CEP13, and CGP32—were selected to determine their potential based on pulp yield and physical properties. Methods: The wood samples from these clones were cooked using the sulfate process with active alkali concentrations of 13% and 15%, 25% sulfidity, a wood-to-liquor ratio of 1:4, a cooking temperature of 170°C, and a cooking duration of 2 hours. Pulp yields, kappa numbers, and pulp properties, including tear, burst, and tensile indices, were analyzed. Statistical analysis employed Analysis of Variance (ANOVA) and Honestly Significant Difference (HSD) tests. Findings: The clones CEP13 and CGP32 achieved higher screened yields at 38.34% and 38.26%, respectively, compared to CEP06. However, CEP06 demonstrated superior tear and burst indices of 6.36 mN·m²/g and 3.60 kPa·m²/g, respectively. The highest tensile index of 41.75 Nm/g was observed in the CGP32 clone. Significant differences were found among the clones in terms of screened yield, kappa number, and certain pulp properties. Additionally, active alkali concentrations significantly affected the screened yield and kappa number, with interactions between clones and alkali concentrations significantly influencing kappa numbers. Conclusion: The CEP06 clone is recommended for pulp and paper production due to its favorable pulp properties, making it an excellent raw material candidate. Novelty/Originality of this article: This study highlights the potential of Eucalyptus pellita clones in optimizing raw materials for pulp and paper industries, emphasizing their specific advantages and contributions to sustainable forestry practices.

Kawui tree or Vernonia arborea is a lesser-known woody species, originated from Kalimantan Island, Indonesia. It is one of the potential materials for pulp and paper, which produces high bark residue. Furthermore, its rich background as folklore medicines suggested the medicinal properties of V. arborea. This study aims to explore the chemical extractives of V. arborea bark and their bioactivities. The bark samples were successfully extracted using n-hexane, methanol (MeOH), and hot water. The n-hexane and MeOH extractives were investigated through GC-MS. For all the fractions, the antioxidant, cytotoxicity, and antifungal activity were evaluated using DPPH (1,1-diphenyl-2-picrylhydrazyl) inhibition method, brine shrimp test, and Phanerochaete chrysosporium attacks, respectively. The MeOH extract showed higher extractive content than the other fractions. The antifungal activity and cytotoxicity were higher in the n-hexane extract. Furthermore, the high antioxidant activity was observed in MeOH extract. The highest of those activities correlate with the presence of alkaloids detected by GC-MS.

Tingi (Ceriops tagal) is considered as one of the natural dyes used in textile dyeing process. The purpose of this study was to determine the effect of extraction duration (20, 40, 60, 80 and 100 minutes) on ultrasonic extraction of tingi bark on yield value, total phenolics content, total flavonoids content, and total tannins content. The yield was calculated by drying the solution with a freezer dryer, while the phytochemical content was calculated by reading method on UV-vis spectrophotometry. The results of the experiment showed that the yield value of the duration treatment was in the range of 1.8 to 2.7%. Total phenolic content ranged from 268.1-314.1 mgGAE/g sample, total flavonoid content in the range of 68.3-87.1 mgQE/g sample, and total tannin content in the value between 244.8-338.1 mgTAE/g sample. The highest compound content was in the duration of 20 minutes.

Shoot waste refers to the parts of trees that are not yet optimally utilized. In this study, we aimed to utilize shoot waste of fast-growing teak (FGT) extracted from the community forest in Wonosari, Gunungkidul, Yogyakarta Special Region, Indonesia by converting it into charcoal, followed by further conversion into activated carbon. This study was conducted with two treatment factors of the activation process, including thermal treatment (750℃, 850℃, and 950℃) and heating period (30, 60, and 90 min), to determine the best condition for the activation process. Our results indicated a significantly effect of the interaction between thermal treatment and heating period on the moisture content, volatile matter content, ash content, fixed carbon content, and adsorption properties of the produced activated carbon. The highest iodine adsorption capacity of activated carbon is 1,102.57 mg/g, which was produced by thermal treatment at 750℃ and heating period of 30 min. This result fulfilled the Indonesian National Standard (SNI 06-3730-1995 quality standard). Furthermore, the quality parameters of the produced activated carbon include: moisture content of 6.13%; volatile matter content of 17.27%; ash content 5.24%; fixed carbon content of 77.49%; benzene removal efficiency of 8.43%; and methylene blue adsorption capacity of 69.66 mg/g. Based on this study, we concluded that shoot waste of FGT could be classified as a prospective material for developing activated carbon for industrial application.