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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.

Additional file 1: Figure S1. MIC of fungus comb extracts against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Figure S2. MBC of fungus comb extracts against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Figure S3. MIC of fungus comb extracts against Aspergillus flavus FNCC 6181 and Aspergillus niger FNCC 6114. Figure S4. MFC of fungus comb extracts against Aspergillus flavus FNCC 6181 and Aspergillus niger FNCC 6114. Figure S5. Chromatogram of GC���MS analysis of the ethyl acetate (a) n-hexane (b) extracts. Table S1. The chemical composition of fungus comb ethyl acetate extract. Table S2. The chemical composition of fungus comb n-hexane extract.

Fitria Cita Dirna,1 Istie Rahayu,1 Akhiruddin Maddu,2 Wayan Darmawan,1 Dodi Nandika,1 Esti Prihatini1 1Department of Forest Products, Faculty of Forestry and Environment, IPB University, Bogor, West Java, Indonesia; 2Department of Physics, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, West Java, IndonesiaCorrespondence: Istie Rahayu Email istiesr@apps.ipb.ac.idIntroductions: Ultrasonication can be used to synthesize nanosilica from silica derived from betung bamboo sticks and leaves. This study aimed to synthesize nanosilica from betung bamboo sticks and leaves by the use of ultrasonication and to characterize the nanosilica produced.Methods: The main materials used in this study were bamboo sticks and leaves. Betung bamboo sticks and leaves were sun-dried and then burned separately without adding fuel to produce charcoal. Then the produced charcoal was burned at a temperature of 700°C for 6 hours in a furnace to produce ash. Silica was extracted from furnace ash using reflux methods. The production of nanosilica from the silica derived from the betung bamboo sticks and leaves was carried out using ultrasonication.Results: The yield of silica from sticks and leaves was based on ash dry weight 45.73% and 79.93%, respectively. The nanosilica derived from betung bamboo sticks had a particle size in the range of 169.87– 1479.50 nm, with an average size of 502.35 nm and a particle dispersion index value of 0.1420. Nanosilica derived from betung bamboo leaves had a particle size in the range of 234.49– 851.36 nm, with an average size of 472.67 nm and a particle dispersion index value of 0.0670. Scanning electron microscopy analysis showed that silica from betung bamboo sticks and leaves still agglomerated. The particle size of silica could minimize through ultrasonication to synthesize nanosilica.Discussions: X-ray diffraction analysis showed that the structure of nanosilica differed from that of silica, and it appeared to be semicrystalline. The ultrasonication method for the synthesis of nanosilica derived from betung bamboo sticks and leaves ash can produce nanosilica that has a semicrystalline phase. The use of surfactants in the process can make the size of the nanosilica particles more uniform and reduce the size of the nanoparticles produced.Keywords: betung bamboo, bamboo sticks, bamboo leaves, nanosilica, ultrasonication

Kerusakan bangunan selama penggunaan (service live) adalah hal yang tidak bisa dihindari. Namun dengan pemeliharan yang tepat, maka bangunan akan lebih awet dan mampu memaksimalkan fungsinya dengan baik. Oleh karena itu setiap bangunan setelah digunakan beberapa tahun harus di analisis, apakah masih layak atau beberapa bagiannya sudah mengalami kerusakan dan perlu pemeliharaan. Penelitian ini bertujuan untuk melakukan inspeksi terhadap keandalan bangunan rumah contoh tahan gempa prefabrikasi yang telah dibangun 10 tahun yang lalu. Metode yang digunakan adalah identifikasi terhadap bagian bagian bangunan, selanjutnya disesuaikan dengan indeks keandalan bangunan. Selain itu juga dilakukan diskripsi terhadap kerusakan dan rekomendasi penting terhadap kelanjutan fungsi bangunan. Hasil penelitian menunjukkan bahwa Bangunan tersebut masuk dalam kategori baik dengan nilai indeksnya adalah 80.3. Secara keseluruhan bangunan masih layak digunakan namun perlu dilakukan sedikit rekayasa dan perbaikan. Bangunan terlihat kurang bersih saat di survey karena tidak lagi digunakan untuk aktifitas harian. Rekomendasi penting adalah perbaikan drainase air, khususnya yang berhubungan dengan bangunan di sebelahnya sehingga kerusakan karena kelembaban bisa diminimalisir.

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