Methylene blue is a cationic dye often used for various industries. Methylene blue waste harms aquatic biota. Most ways have been done to reduce the methylene blue pollution that includes photocatalytic, electrochemical, and adsorption. This study aimed to reduce the impact of methylene blue pollution on the aquatic environment and to test the adsorption isothermal for methylene blue adsorption using coconut fiber. The abundant coconut fiber waste around the Kupang city was taken and prepared to be used as an adsorbent. The characterization results showed that the active groups in cellulose were clearly described on the FTIR spectra which showed the presence of O-H vibrations at 3296.35 cm-1, C-O vibrations were seen at 1267.23 and 1060.85 cm-1, at wavelengths 1608.63 cm-1 and 817.72 cm-1 there is a vibration from the C=C bond, while the C-H vibration appears at a wavelength of 2939.52 cm-1. The results of this research analysis showed that the adsorption of methylene blue according to the Langmuir isotherm indicated by the value of the equation of the straight line R2 being one and the direction of the curve depicting occurring the effective adsorption. The maximum adsorption capacity was 4.467 mg g-1 with the percentage of methylene blue adsorbed at 99.3%. Adsorption occurs chemically with an energy of 27.29 kJmol-1 so it can be determined that the adsorption occurs with a monolayer mechanism.

Sambiloto (Andrographis paniculata) is widely used as a medicinal plant for Indonesians. The content of extracted bioactive compounds is affected by the polarity of the extraction solvent. This study aims to determine the effect of extraction solvent on the chromatographic profile of Sambiloto herb, especially terpenoid group using the TLC-Spectrophotodensitometry method. Sambiloto herb was extracted by sonication method using methanol, ethanol, ethyl acetate, and chloroform as the solvents. Chromatographic profiles were identified by stationary phase of TLC silica gel GF254 plate and a mobile phase of chloroform:methanol (10:1 v/v), observed visually, and scanned at 210 nm. The plate was sprayed with anisadehyd-sulfuric acid reagent and observed visually. The compounds that belong to terpenoid compounds, namely S2, S5, S8, S11, and S12, had a greater percentage of peak area than the total area so that they were categorized as major components. The extraction solvent for Sambiloto herb that provides the best chromatographic profiles was found in the solvent of methanol extraction.

Biodiesel is currently getting great attention because it can reduce carbon dioxide emissions by 78.5% compared to petroleum-based diesel. The reaction that can produce biodiesel is the esterification reaction with the addition of a heterogeneous catalyst, one of which is SnO2 which can be used as Lewis acid for the esterification reaction. In our study, SnO2 has been successfully synthesized and then succeeded in reducing the level of oleic acid FFA (Free Fatty Acid) through an esterification reaction. SnO2 was synthesized from SnCl2.2H2O using the hydrothermal method with the addition of CTAB (Cetyl Trimethyl Ammonium Bromide) as a capping agent which was then analyzed using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscopy). The catalytic activity of the SnO2 sample was carried out through the esterification reaction of oleic acid in ethanol at 65 °C for 6 hours with variations in catalyst weight and variations in the ethanol mole ratio. From XRD analysis, SnO2 sample consists of cassiterite minerals and has typical peaks at 2? = 26.56°; 33.84°; 37.92°; 38.90°; 42.53°; 51.64°; 54.66°; 57.76°; 61.68°; 62.34°; 64.60°; and 65.88° with the highest intensity at 2? = 33.84°. During condition optimization of esterification reaction of oleic acid, variations in the weight of SnO2 catalyst resulting from the optimum FFA level could be reduced by 75.05%, whereas to variations in the mole ratio of ethanol, the optimum FFA level could be reduced by 85.53%. In our study, SnO2 has been successfully synthesized and then succeeded in reducing the level of oleic acid FFA through esterification reaction until 85.53%.

The Tembakul fish (Mudskipper) is one of the unique fauna resembling amphibian fish that can adapt to two different natural conditions. Boleopthalmus sp is one of three types of Mudskipper that inhabit the mangrove ecosystem in Mempawah. The purpose of this study was to produce fishmeal from Mudskipper Boleopthalmus sp and determine the nutritional content in the form of proximate and essential minerals based on variations in drying treatment before the flouring process. The study was carried out in November-February 2021. Samples were obtained by collecting randomly the Mempawah mangrove area and processed with five different treatments or preparations for flour processing, namely drying with salt, drying without salt, frying with oil, frying without oil, and drying with oven. Nutrient content in the form of proximate in fresh Boleopthalmus sp is fat (0.1 %), protein (20.67 %), water (81.02 %) and ash (1.69%), with phosphorus mineral content (2.06 %), calcium (1.20 %) and iron (259.16 ppm). From these five preparations for processing the fishmeal, it showed that fishmeal was processed by drying without salt before being floured with the flour yield (20 %), fat content (2.18 %), protein content (68.7%), moisture content (15.27 %), and ash content (9.17 %).

The oil palm empty fruit bunch (OPEFB) is one of the solid wastes produced by industrial factories. These bunches are the habitat of cellulolytic bacteria. This study aims to identify the morphology and determine the potential microorganisms in degrading oil palm empty fruit bunches waste. The methods used in this study were isolation and observation of bacterial morphology, bacterial screening, degradation test of empty oil palm fruit bunches waste, and enzyme activity test with DNS method using UV-Vis spectrophotometer at a wavelength of 530 nm. A collection of 14 isolates were obtained from the isolation process. We obtained 14 isolates from the sample, the largest clear zone was shown by isolate S10. The isolate also exhibited the highest cellulose-degrading activity after 7 days incubation period with a degrading percentage of 13.27%. After incubation for 2 days, the morphological characteristics of the bacteria produced have circular and medium-sized colonies, yellow, colonies wave edges and flat colonies, elevation convex and smooth surface. The resulting enzyme activity was 0.1308 U/mL. Therefore, isolate S10 was suspected to have the potential to degrade plastic.

In this work, a facile enhanced property of Ag3PO4 photocatalyst using H2O2 for methylene blue photodegradation has been conducted. Ag3PO4 photocatalyst was synthesized using the co-precipitation method. Then, the photocatalytic activity and stability of Ag3PO4 were tested in the methylene blue degradation under the addition of an H2O2 30% solution. According to the results, the prolonged photocatalysis reaction led to a decrease in the catalysis ability of the Ag3PO4 photocatalyst. Meanwhile, the addition of 5 mL of H2O2 (AH-10% sample) tends to enhance the stability of Ag3PO4 photocatalyst with the dye removal percentage and recycling test were up to 90.3% and three recycle runs, respectively. The low stability of Ag3PO4 might be due to the catalyst photo-corrosion through Ag+ reduction. This research suggests that H2O2 is beneficial to inhibit the photo-corrosion of Ag3PO4 photocatalyst, even though released Ag ions that were caused by the excess addition of H2O2 oxidizing agent should be considered.

The use of pesticides in nutmeg still leaves an accumulation of pesticide residues that can endanger human health and damage the ecological balance. In addition, nutmeg with high pesticide residue content will be rejected by nutmeg export destination countries. This research was conducted to validate the method of testing pesticide residues of carbaryl, carbofuran, acetate, and dimethoate on nutmeg. This pesticide residue test uses the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) optimization method and is analyzed using UPLC-MS/MS (Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry). This method meets the validation requirements according to SANTE/12682/2019. The limit of quantification (LOQ) of the analyte is below the Maximum Residue Limit (MRL) set by the European Union through Regulation (EC) No. 396/2005.

Cervical cancer is one of the most prominent death cases after breast cancer for a woman in Indonesia. Several treatments can be conducted to cure cancer such as chemotherapy, radiotherapy, tumor surgery, and others. In addition, people can consume some medicines or natural substances that can suppress cancer growth. The natural substances contain active compounds that have the potential as anticancer. One of the natural substances used in this research is the Namnam leaves which grow in Southeast Asia. The purpose of this research was to determine the potential compounds in Namnam leaves extract by cytotoxic activity testing by using HeLa cells. The active compound in the Namnam leaves extract was obtained by using the maceration method with ethanol for 3x24 hours. The extract was then tested by BSLT method and proliferation by using HeLa cancer cells (ATCC CCL-2). The toxicity results showed that LC50 value was 125,89 µg/mL. This result indicated that the extract belongs to the moderate toxic category and has potential as an anticancer agent. Proliferation test in inhibiting of HeLa cancer cells used Microculture Tetrazolium Technique (MTT) method. The result showed that the extract with a concentration of 25 µg/mL could inhibit the proliferation of HeLa cancer cells by 57,51%

The use of coffee plants is more focused on the coffee beans as a brewing drink or as a food additive. Parts of the coffee plant, such as leaves, are considered waste and have not been properly utilized. This study aimed to determine the phytochemical content and antioxidant activity of the methanol extract in Arabica coffee (Coffea arabica) leaves. The method used in this study was the extraction and DPPH method (1,1-diphenyl-2-picrylhydrazyl). The results showed that the Arabica coffee leaves contained flavonoids, alkaloids, terpenoids, and phenolic compounds. The antioxidant activity test showed an IC50 value of 57.699 ppm with the strong antioxidant category.

The study of the Quantitative Structure-Activity Relationship (QSAR) of eugenol compound and its derivatives towards antioxidant activities was conducted using electronic and molecular descriptors. These descriptors were generated from semi-empirical chemical computation with PM3 level of theory. The QSAR model in this research could be used to predict novel antioxidant compounds which are more potent. The activity of the compound determined based on the IC50 value (Inhibition Concentration 50%) was linked with the descriptor results that had been calculated in a QSAR equation. The data showed that the descriptors that had a significant effect were a net charge of C-6, C-7, O-12, and HOMO energy and hydration energy. The best QSAR equations obtained with these descriptors and their parameters are shown as follows. log1/IC50 = - 3,3026 (± 0,4066) qC6 - 4,7450 (± 0,7224) qC7 + 3,2746 (± 0,6752) qO12 + 0,6326 (± 0,0645) HOMO - 0,0086 (± 0,0011) hydration energy + 4,8053 (± 0,6336) (n = 8 ; R = 1,000 ; s = 0,004 ; F = 3655,537 ; p = 0,0003 ; Q2 = 0,988 ; SPress = 0,039 ; SDEP = 0,021)

Titanium Silicate-1 (TS-1) has been successfully modified by combining Silver (Ag) metals. In this study, the preparation of Ag/TS-1 was carried out by impregnation method using a solution of silver nitrate (AgNO3) as a precursor to TS-1 with a loading variation of 0.5%, 1%, 2%, and 4%. Impregnation carried out on TS-1 aims to disperse Ag (1) only attached to the surface of TS-1 particles (before calcination/TK) and (2) on the entire surface of TS-1 particles (after calcination/K). The synthesized catalyst was then characterized by X-ray diffraction, infrared spectroscopy, and pyridine adsorption techniques. The XRD pattern shows that all the catalysts have high crystallinity with MFI structure, and there is no other crystalline phase. The infrared spectra showed that the titanium tetrahedral in TS-1 remained after Ag impregnation. The TS-1 and Ag/TS-1 catalysts were analyzed for their surface acidity using pyridine adsorption on the sample. The pyridine adsorption technique showed the presence of Lewis sites on Ag/TS-1. In this study, the presence of Ag loading on the Ag/TS-1 catalyst affected the TS-1 catalytic activity. The amount of cyclohexanone oxime product produced in XAg/TS-1 was more than in Ag/TS-1.