Tree failure is an international problem, a major risk to public safety, and of growing concern because of extreme weather events. Tree biomechanics can inform the probability of tree failure, but empirical data from tropical settings are scarce. As a case study, we analyze the biomechanics (safety factor) of large heritage trees in public spaces in Indonesia. We examined critical buckling height using the Euler and Ylinen bending stress method. Tree morphometry (height, diameter at breast height, crown diameter), stability (modulus of elasticity), critical buckling height, and safety factor were quantified during this study. We found that large heritage trees in public spaces with buttresses have taller and larger morphometry and higher trunk and crown weights than small trees without buttresses. These trees are highly stable against external pressure. The presence of buttresses protects the target tree from rain and wind, resulting in a higher critical buckling height (Hcr) of large (58.9 m) and buttressed target trees (58.8) than small (33.5 m) and unbuttressed trees (42.6 m), and a safety factor level of 68% safer. We make recommendations for selecting and managing trees in public spaces in a way that (i) can enhance wellbeing and biodiversity in urban planning, and (ii) is informed by risk to public safety.

Wood-destroying termites are quite influential in Indonesia, and the subterranean termite Schedorhinotermes javanicus is one of them. This study was conducted to determine the feeding preferences of subterranean termites S. javanicus on tusam (Pinus merkusii) wood and the influence of their environment. The bait woods made of tusam boards were installed at the experimental site. The weight loss and consumption of bait woods were studied with three test times (one, two, three) months of burial. The subterranean termite specimens attacking the bait woods, soil characteristics, and weather at the experimental field were also identified. The results demonstrated that the average air temperature at the experimental site was 25.4 ± 0.4°C, the average air humidity reached 88.8 ± 2.4%, and the light intensity at the experimental site ranged from 175.67 lux to 3889.7 lux. The results showed that S. javanicus quite actively attacked the bait wood. This can be seen from the high weight loss (35.03%) and the wood consumption (38.78 g). The weight loss after three exposure times in the experimental field was up to 13.54%, 16.38%, and 35.03%, respectively. The wood consumption during the same experimental period reached 14.9 g, 18.25 g, and 38.78 g, sequentially. The high weight loss and the consumption of bait wood indicate the high feeding preference of the subterranean termites S. javanicus on tusam wood. Keywords: field test, Pinus merkusii, Schedorhinotermes javanicus, weight loss, wood consumption

Subterranean termite attacks on cajuput (Melaleuca cajuputi) seedling roots were widespread in several of Java’s Perum Perhutani Forest Management Units. This attack was suspected to be related to the chemical components of the cajunput seedling roots. This study was conducted to determine the bioactivity of cajuput seedling root extract as an attractant for the subterranean termite Coptotermes curvignathus Holmgren (Isoptera: Rhinotermitidae). The extraction process was performed according to ASTM D1108-96, and the extract was characterized using gas chromatography-mass spectrometry (GC-MS). Bioactivity testing of the extracts was carried out using attractiveness and no-choice feeding bioassays. The results showed that the average root extraction yield from cajunput seedlings was 4.94%. The attractiveness of the extract solutions at concentrations of 0.50%, 0.75%, and 1.00% were 45.33%, 62.00%, and 74.67%, respectively. The mortality rate of C. curvignathus termites ranged from 9.63% to 24.44%. Cajuput seedling root extract’s lethal concentration 50 was 2.45% (non-toxic). GC-MS analysis showed that the extract contained linoleic acid, which has the potential to attract insects.

Forest Health Monitoring (FHM) and International Society of Arboriculture (ISA) methods are used for individual tree health assessment. However, comparing the reliability of both methods in assessing large and old tree health has yet to be evaluated. This study aims to determine reliability of two methods in evaluating the health condition of old (>100 years old) and large Dipterocarp trees in Bogor Botanic Garden (BBG), Indonesia. The parameters observed were growth, morphometry, and tree health of 44 trees. The results showed that, overall, the two methods demonstrated quite similar in assessing the health condition of targeted trees. Visual tree damage domination by conks, fruiting bodies, and other indicators of advanced decay, open wounds, and termite gallery. The average risk rating of three parts of the tree (branches/crown, trunk, roots) is low to moderate. The two approaches could be used simultaneously or separately according to the purpose of the assessment.

Currently, two standard methods are used for individual tree health assessment, i.e., (1) the forest health monitoring (FHM, focused on the individual tree level by assessing damage indicators) method developed by the International Tropical Timber Organization (ITTO) and (2) the Visual Tree Assessment (VTA) method developed by the International Society of Arboriculture (ISA). However, comparing the reliability of both standards in assessing the health of large and old tree needs has not been evaluated. This study aims to determine the reliability of the two methods in evaluating the health condition of old and large Dipterocarp trees grown in Bogor Botanic Garden, Indonesia, that are >100 years old. The parameters observed were growth, morphometry, and tree health of 44 dipterocarp trees. The FHM method at the individual tree level measures the damage's location, type, and severity, then calculates the tree health-level index. In comparison, the VTA method includes the assessment of tree defects and conditions and how it contributes to the likelihood of failure. The risk rating of the tree is then computed and calibrated. The equivalency of the tree health-level index and risk rating of the targeted trees were evaluated. The results showed that, overall, the two methods demonstrated quite similar reliability in assessing the health condition of the targeted trees. FHM and VTA methods reveal that the old and large Dipterocarp trees in Bogor Botanic Garden had a higher failure rate. The two approaches could be used simultaneously or separately according to the purpose of the assessment (tree health-level index or risk rating).

The root system is important for supporting tree growth and stability. In this study, we analyzed the relationship between the main lateral root distribution pattern and vertical tree growth direction based on root detection and analysis of tree morphometry. Tree growth represented by morphometric data were measured directly, and the root distribution was identified using a sonic Root Detector. Sixteen targeted trees (eight Samanea saman and eight Delonix regia trees) in an urban area landscape were selected in this study. The Root Detector revealed that the average sonic velocity of lateral roots was 676.88 m∙s−1 for S. saman and 865.32 m∙s−1 for D. regia. For root distribution, Root Detector determined the average numbers of main lateral roots for S. saman and D. regia, which were 6 and 10, respectively. Based on correlation analysis, significant relationships were found between tree root sonic velocity and the degree of lean, height, and diameter of the tree; meanwhile the relationship between crown diameter and slenderness were not significant. Findings confirmed that, in relation to the root distribution and the growth direction of the trunk and crown, the lateral root is mainly distributed in the opposite direction of the tree lean rather than crown growth direction.

The innovation in the proposed termite detection system can detect and predict the population non-destructively based on acoustic and temperature signals. This study aims to identify the characteristics of acoustic and temperature signals of subterranean termite infestation. Various termite populations were inserted into the pine board for 21 days as a feeding test, then infestation was monitored through the continuous acoustic-temperature signals response after 24 h. Based on the signal analysis, the peak of daily termite activity can be found in the afternoon, while the evening until early morning contained significantly less activity. This fluctuation was significantly associated with ambient temperature, the higher the temperature, the greater the activity. Furthermore, the signal analysis revealed that the higher the termite population, the warmer the board temperature with an average of 0.101 degrees C. Based on the results, extensive knowledge is essential to effectively develop the signal processing package in the termite detection system.

The authors have recently investigated the chemical components and bioactivity of fungus comb from Macrotermes gilvus Hagen mounds. The ethyl acetate, methanol, and water extracts of the fungus comb contained active compounds which are preventing the growth of Aspergillus foeti-dus, one of the most economically important wood-staining fungi in Indonesia. In this present study, the bioactivity of the fungus comb extracts was examined against the white-rot fungus Schizophyllum commune Fr. For the purpose of generating a realistic in-service type of environment, the extracts were evaluated according to modified EN-113 after impregnated into wood samples by the vacuum-pressure method, following in-vitro antimicrobial susceptibility test. The results showed that ethyl acetate extract at concentrations ranging from 2 to 6% and methanol extract at a concentration of 6% presented high bioactivity against S. commune. This result was established through optical microscopy images, which demonstrated the absence of fungal mycelia in the vessels of wood samples treated with EtOAc extract at concentrations of 2%, 4%, and 6%, as well as MeOH extract with a concentration of 6%. The toxic values of the ethyl acetate and methanol extracts were determined to be 6.17% and 7.72%, respectively. Based on UPLC-HRMS analysis, azelaic acid, and erucamide were discovered as the dominant components in ethyl acetate extracts, which are anticipated to be the most active compounds. It appears that ethyl acetate extract, as well as methanol extract, can be considered as novel preservative sources for controlling wood-decaying fungi.

Abstract. Witasari LD, Lizar DP, Florencia OM, Ramadhan A, Fiana NAO, Supriyadi S, Pratiwi SUT, Nandika D, Karlinasari L, Arinana A, Batubara I, Santoso D, Rachmayanti Y, Firmansyah D, Sudiana IK, Hertanto DM, Rachmayanti Y, Firmansyah D. 2023. Designing antimicrobial active packaging films based on chitosan plus fungus comb ethyl acetate extract from Indo-Malayan termite mounds. Biodiversitas 24: 5947-5955. Antimicrobial active packaging systems incorporate antimicrobial compounds into polymer films, i.e., chitosan, thus suppress spoilage microorganism growth in foods. Chitosan films itself cannot prevent microbial growth, thus other antimicrobial agent must be added. Fungus comb extract from Indo-Malayan termite (Macrotermes gilvus (Hagen, 1858)) mounds is a potential active organic antimicrobial compound, which can be incorporated into chitosan films. The purpose of this study was to develop and characterize active packaging films based on chitosan plus an antimicrobial fungus comb ethyl acetate extract. Films contained 1% chitosan and fungus comb ethyl acetate extract (0.5, 1, 2, and 5% w/v). Notably, films containing 2 and 5% extracts inhibited Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), and Pseudomonas aeruginosa (ATCC 27853), but not fungi. Films plus 2% extract showed a thickness, tensile strength, and strain of 0.13 mm, 2.15 MPa, and 32.55%, respectively. Films had a moisture content of 0.26%, water solubility of 2.68%, swelling property of 2.37%, and water vapor permeability (WPV) of 3.31×10?10 g.m?1s?1.Pa?1. They displayed smooth morphology but no new functional groups. Thus, chitosan plus 2% of fungus comb ethyl acetate extract can be used in antimicrobial active packaging films for food application. It could be applied as a green alternative to prolong the shelf-life of food products.

Fungus comb is a structure made by termite colony Macrotermitinae with lots of potential because it contains secondary metabolites such as steroids, terpenoids, and saponins and compounds containing antioxidant and anti-tyrosinase properties. This study aimed to determine fungus comb extracts' fingerprint pattern, antioxidant capacity, and anti-tyrosinase activity. Thin layer chromatography (TLC) was used to determine fingerprint patterns. The resulting TLC pattern was processed with ImageJ and converted into a densitogram. The fungus comb was extracted with n-hexane and ethyl acetate. TLC results showed that fungus comb extracts contain steroids and terpenoids and have antioxidant properties. The antioxidant capacity assay was carried out with 2,2-diphenyl-1-picrylhydrazyl reagent. N-hexane extract had an antioxidant capacity value of 9.07 mg ascorbic acid equivalent (AAE)/g extract, while ethyl acetate extract had 6.04 mg AAE/g extract. Anti-tyrosinase activity assay was carried out with L-tyrosine and L-3,4-dihydroxyphenylalanine (L-DOPA) as substrates. N-hexane extract had a better anti-tyrosinase activity with IC50 of 1804 µg/mL for L-tyrosine and 6784 µg/mL for L-DOPA.

Recently, the morphological and molecular features of five stain fungi infecting rubberwood (Hevea brasiliensis), namely Paecilomyces maximus, Paecilomyces formosus, Penicillium crustosum, Paecilomyces lecythidis and Aspergillus chevalieri, have been studied.Prior to this study, the authors revealed that catechin from gambir (Uncaria gambir) could inhibit the growth of the white-rot fungus Schizophyllum commune, and it was important to determine the bioactivity of the aforementioned agent against A. chevalieri.The efficacy of the biocidal agent was examined using a laboratory wooden block test.Rubberwood blocks, 8 mm in thickness, 20 mm in width, and 30 mm in length, were impregnated with catechin solution at concentrations of 6%, 9%, 12%, and 15% (w/v) using the vacuum-pressure method, and their bioactivity was monitored over three weeks through visual and scanning electron microscope assessment of fungal growth as well as the discoloration intensity of the wood samples.The results showed that catechin treatment increased the resistance of wood samples to A. chevalieri.Overall, the higher the catechin concentration, the lower the fungal growth.The lowest fungal growth was observed in the wood samples treated with 12% and 15% catechin (score of 0), demonstrating no discoloration.In contrast, the fungal growth score of the untreated wood samples reached 4, indicating severe discoloration.Catechins appear to be adequate biofungicides against stain fungi in rubberwood.

Jakarta has become one of the cities with the highest air pollution levels among emerging countries. In urban areas such as Jakarta, trees on the roadside have the potential for biomonitoring due to significant pollutants sourced from the traffic. The bark provides information about air pollution due to its furrowed surface and collects atmospheric particle matter (PM). Therefore, the structure of the bark and surface pollutants of 20 rain trees ( Samanea saman (Jacq.) Merr.) in the four lots at Sudirman Central Business District (SCBD) Jakarta were assessed. The study aimed to evaluate of air condition in the SCBD area based on the analysis of the bark structure and concentrations of important pollutant elements of Pb (plumbum), Cd (cadmium), Cu (cuprum), Cr (chromium), Mn (manganese), and Zn (zinc) on the bark. The results showed the bark thickness ranges from 3-9 mm with an average of 6.13 mm. The cuticula was gray-black in color, the phloem was brownish, and the cambium layer was very thin. Cu, Cr, Mn, and Zn were detected based on the analysis of the elements. However, Cd was not found in all trees in these four lots. Furthermore, Mn is the dominant pollutant in all trees, more than 40 ppm or more than 69% of the total, followed by Cu, Zn, and Cr. Based on the result, pollutant analysis through accumulated matter on the bark have the potential to be used as biomonitoring in urban areas.

Indonesian termites are one of the wealthiest biological resources considering their very high species diversity (300 species) and extensive geographical distribution in the Indonesian mainland. However, its potential as a source of bioactive compounds has not been fully explored. One of the endemic termite sub-families of Indonesian, Macrotermitinae (Isoptera: Termitidae), has a food source in the form of fungal nodules that grow and spread in a particular structure in the termite nest that is shaped like a mammalian brain called a fungus comb, which likely serves as a source of bioactive compounds. This study aims to analyze the potential of fungus comb from an Indonesian Macrotermitinae sub-family species as a source of antioxidants. Antioxidant activity was tested on four different extracts of fungus comb (EFC), namely hexane extract, ethyl acetate extract, methanol extract and water extract, using DPPH• (1,1-diphenyl-2-picrylhydrazyl) and ABTS•+ (2,2′-azino-di-[3-ethylbenzthiazolinesulphonate]) radicals. The results showed that the highest antioxidant activity was found in methanol extract, followed by ethyl acetate extract with IC50 values of 0.6 mg/mL and 0.75 mg/mL, respectively. TEAC (Trolox equivalent antioxidant capacity) analysis confirmed the high antioxidant activity of methanol extract.

Termites are the most important invertebrate in the

The embodiment of antimicrobial components into the food packaging material has the ability to prevent microbial contamination. Fungus comb could be an alternative source of natural antimicrobial agents. In this study, n-hexane, ethyl acetate, methanol, and water extracts from fungus comb isolated from Indo-malayan termite Macrotermes gilvus Hagen mound were analysed for its antibacterial and antifungal activities against food spoilage microorganisms, including Escherichia coli ATCC 25922, Pseudomonas aeruginosa AT CC 27853, Staphylococcus aureus ATCC 25923, Aspergillus flavus , and Aspergillus niger. The antimicrobial activity of the fungus comb extracts was evaluated using Kirby-Bauer disc diffusion and microdilution method. The result showed that ethyl acetate extract exhibited the biggest diameter inhibition zone for all bacteria and fungi tested. Ethyl acetate extract showed antibacterial activity in all bacteria with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.39 mg/mL and 0.78 mg/mL, respectively. This extract also inhibited A. flavus and A. niger with MIC value of 0.78 mg/ml. Ethyl acetate extract contained guaiacol and syringol, which were predicted as the main antimicrobial components in fungus comb. Whereas n-hexane extract only inhibited Gram-positive bacteria. S. aureus ATCC 25923 was the most sensitive bacteria tested using all extracts. In addition, A. flavus was more sensitive compared to A. niger . Overall, fungus comb extract exhibited antimicrobial activity against E.coli ATCC 25922, P. aeruginosa ATCC 27853, S. aureus ATCC 25923, A. flavus , and A. niger . This study revealed that the fungus comb extract, especially ethyl acetate, could be considered as a new antimicrobial agent.

ABSTRACT An extreme inclination angle of helical cutting tool edge has been developed in milling of new commercially wood-based materials. The purpose of this research was to investigate wear resistance, chip flow and shape, surface roughness, and noise level of helical edge cutting tools in milling wood-based materials. The wood-based materials of wood plastic composite, laminated veneer lumber, and oriented strand board were cut by the helical edge cutting tools (inclination angle of 15°, 30°, 45°, 60°, and 75°) in the up-milling and down-milling processes on a computer numerical control router. Feed speed was set up in 2, 3, and 4 m/min. The results show that the helical edges provide better wear resistance, better surface quality, and lower noise emission compared to the conventional edge (0°). Edge radius wear, chip flow area and flight speed, surface roughness, and noise level decreased with increasing the inclination angle of the cutting tool edges. The differences in the wood-based material structure, the milling process, and the feed speed resulted in the difference in cutting tool wear, chip flow and shape, surface roughness, and noise level phenomenon.

Rain tree (Samanea saman) is a dominant species commonly planted as a shade tree in urban landscapes in the tropics, including in Indonesia. This species is also targeted for routine inspection and monitoring within tree management systems. Management should particularly focus on tree health through assessment of tree growth conditions as well as tree stability. However, baseline information on the relationships of many key characteristics for the rain tree (e.g., growth, morphometrics, and biomechanics) is lacking. Therefore, an investigation was carried out to determine the relationship of morphometric parameters to tree growth, which included use of an acoustic tool to assess the elasticity of the tree stem. Fifty rain trees were selected for data collection and evaluated using stress wave velocity tools and visual morphometrics assessment. The results demonstrated that, in general, the trees had good vigor and stability. Statistical analysis showed a strong relationship between tree growth parameters and selected morphometric characteristics. The use of a nondestructive acoustic-based instrument enabled determining the modulus of elasticity, which provided equivalent results with the elasticity value obtained through a common method for determining tree stability. Only live crown ratio and tree slenderness parameters had a relationship with the dynamic modulus of elasticity. These results offer a means of measurement that is simpler, less expensive, and faster than current methods, although further testing is needed for different tree species and growth sites.

Recently, the architectural and physical properties of the fungus comb from subterranean termite Macrotermes gilvus Hagen (Isoptera: Termitidae) mounds had been studied and it is important to determine its chemical profile as well as to evaluate its anti-staining-fungi activity. The results showed that fungus comb of M. gilvus has a high crude ash (30.57%), fiber (25.46%), starch (7.76%), protein (5.80%, 5.53% amino acid), acid-insoluble ash (3.45%), and fat (0.73%). It also contained phenol hydroquinone, steroids, terpenoids, and saponin compounds. Seventeen amino acids were identified via high-performance liquid chromatography analysis, of which arginine, leucine, glutamate, and aspartic acid were the majority. According to gas chromatography-mass spectrometry analysis, the n-hexane extract consists of several types of fatty acid derivatives. Meanwhile, the ethyl acetate (EtOAc) extracts were primarily phenol groups with 1,2,3-propanetriol (glycerol) at the highest relative concentration. Four fungus-comb extracts (n-hexane, EtOAc, MeOH, and water) inhibited the Aspergillus foetidus fungus, with inhibition rates ranging from 24.17% to 100% and EtOAc extract as the most active extract. It appears that EtOAc extracts from the M. gilvus fungus comb can be considered an active ingredient source of novel organic fungicide in preventing wood-staining fungi attacks on susceptible wood.