Chitosan-silica hybrid adsorbent has been successfully synthesized by extracting the silica of Timor Island-East Nusa Tenggara (NTT) in order to study its application to Cu 2+ adsorption in water samples. This work consists of several steps which include silica extraction from Takari sand of East Nusa Tenggara, preparation of chitosan-silica hybrid, FTIR and SEM characterization, and adsorption of Cu 2+ . The successful extraction of silica was indicated by the existence of-OH, siloxane (Si-O-Si), Si-O in silanol (Si-OH) peaks at 3433.29 cm -1 ,468.70 cm -1 , and 958.62 cm -1 , respectively. The formation of chitosan-silica hybrid adsorbent was denoted by a peak shift of-OH in silica to3404.36 cm -1 , N-H stretching vibration at 1544.98 cm -1 due to an interaction between O-H in silica with N-H in chitosan, and amine (primary-NH) bending vibration at1639.49 cm -1 . The surface morphology of silica changed when it was modified with chitosan from homogeneous granule to a cluster (larger particle sizes). Optimum adsorption conditions toward Cu 2+ were achieved at pH 8 and contact time of 50 min, resulting in excellence adsorption efficiency of 99.3%. Adsorption of Cu 2+ fitted Langmuir isotherm with the adsorption capacity of 27 mg/g.
Mangrove forest has a distinctive habitat adapting with marine and terrestrial environment. Chemical investigation of the extract from mangrove endophytic fungi Nigrospora oryzae had resulted in the isolation of sterigmatocystin (1) and pestalopyrone (2). The structure of sterigmatocystin (1) and pestalopyrone (2) were elucidated using mass, UV and NMR spectrometers together with the comparison with the literature data. The study also showed that sterigmatocystin displayed moderate cytotoxicity but it could be further developed as antiviral and antibacterial agent based on the SAR information reported from its analogue and derivatives.
Kabate larva oils could be produced from its larva through soxhlet extraction using n-hexane. Kabate larva, which locally in Timor Island called, can be found in the wounded stem of Sesbania gradiflora L. tree. In this work, the physicochemical properties and the fatty acid composition of Kabate larva oils were evaluated. Kabate larva oils was afforded as viscous yellow liquid with acid value, saponification value, peroxide number, iodine number, kinematic viscosity (at 100 °C) and specific gravity (15 °C) properties were 1.58 mg KOH/g; 111.28 mg KOH/g; 2.1554 meg/kg; 44.1426; 0.8159 g/mL; 40.57 mm 2 /s respectively. Based on the GC-MS analysis, it has been found out that fatty acids composition in Kabate larva oil were identified as a palmitic and oleic acid with a percentage value of 43.57 and 56.43% respectively.
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