Background: Ganoderma fungus is rich in terpenoids. These compounds are known for their anti-hyperglycemic activities. However, the study of terpenoids as the secondary metabolite from Ganoderma as a dipeptidyl peptidase-4 (DPP-4) inhibitor remains unexplored. In addition, we examined the α-glucosidase inhibition activity. Objective: This study aimed to isolate the major terpenoid from non-laccate Ganoderma and examined its inhibitor activity on DPP-4 and α-glucosidase enzymes, and its interaction. Methods: The compound was isolated using column chromatography from Ganoderma australe. The structure of the isolated compound was confirmed by 1H and 13C nuclear magnetic resonance spectroscopy, while the inhibitory activity was evaluated using an enzymatic assay. The interaction of the isolated compound with DPP-4 and α-glucosidase enzymes was investigated using an in silico study. Results: The isolated compound was identified as stellasterol; IC50 values for DPP-4 and α-glucosidase inhibitor were 427.39 µM and 314.54 µM, respectively. This study revealed that the inhibitory effect of stellasterol on DPP-4 enzyme is through hydrophobic interaction, while the α-glucosidase enzyme is due to the interaction with six amino acids of the enzyme. Conclusion: Stellasterol is the major component of the steroid from G. australe. Enzyme inhibitory assay and in silico study suggest that stellasterol may contribute antidiabetic activity with a mechanism closer to acarbose rather than to sitagliptin.

Recently, the development of nanoparticle nickel oxide has increased due to their potential application such as biosensors, catalysts, solar cells, supercapacitors, and batteries. In this work, the addition of CTAB for nickel oxide nanoparticle synthesis using electrolysis was investigated.  The nickel plates were used as anode and cathode in the electrolysis process. The process was operated at a constant voltage of 60 V for 30 minutes. The XRD result showed conformity with the Nickel oxide diffraction pattern. Meanwhile, the impurity from nickel hydroxide peaks still appeared. From FTIR characterization also indicates the band of Ni-O stretching vibration. The morphology characterization of nickel oxide using Scanning Electron Microscopy (SEM) showed the nanotube structure, while Transmission Electron Microscopy showed the nanoparticle size from 250.44 to 325.60 nm in length. On the other hand, the transformation of Ni(OH)2 to NiO has been shown using TGA characterization.

Modern batik is one of the fashion trends that are always in demand by the market. When choosing batik, many factors are considered including the type of batik (writing or stamp), fabric material, motif, quality, color, price, and design (model). Of all these factors, the most influencing people in buying batik are prices, motifs, colors, and designs (models). This study used Eigen Values and Vectors to determine the priority of factors that influence batik purchases. To find out the factors that are most in demand by the market among the four factors (price, motif, color, and design), the study was conducted by providing a questionnaire containing a comparison between one factor and another. Respondents write down which factors to choose and give weight to each choice. The next step is to calculate the eigen values and make a decision based on the normalized eigen vector.

In this study we compared the synthesis of nickel hydroxide nanoparticles using two different solutions, namely tween 20 and PEG (Polyethylene Glycol) 400, the electrolysis method used 0.3 M sodium citrate with the addition of tween 20 and PEG 400, using a potential of 25 Volts for 30 minutes. Obtained nickel hydroxide nanoparticles. Scanning electron microscopy (SEM) is used for morphological characterization of the product. Nickel hydroxide nanoparticles added with tween 20 were in the form of nanoflowers, while nickel hydroxide nanoparticles added with PEG 400 were in a spherical shape. Keywords: High Voltage,Electrolysis, Ni(OH)2 nanoparticles

Biobriquette can be used as an alternative fuel because it is made from inexpensive materials and uses simple technology, and it is expected to help overcome the energy (fossil) crisis. The problem is determining how to boost the calorific value of briquettes made from waste biomass materials. Cabbage contains approximately 18.80% fiber, so there is cellulose content that can be processed into high-value products such as briquettes, and using rice husks as fuel can increase the calorific value. The goal of this study is to determine the best calorific value of biobriquettes by varying the method of adding coconut oil and the composition of rice husks and cabbage. The stages of making cabbage and rice husk biobriquettes are raw material preparation, carbonization, adhesive manufacture, briquetting, and quality testing. The variables used are variations in the composition of rice husks: cabbage in ratios of 40:60, 50:50, 60:40, 70:30, and 80:20, as well as the variable method of giving palm oil by mixing with ingredients and dyeing after it becomes briquettes. According to the findings of this study, the best biobriquette mixing ratio resulted in the highest calorific value found in a mixture of 40% rice husk and 60% cabbage with the method of adding palm oil by dipping, with a calorific value of 6.283 kcal/g, a combustion rate of 0.0616 g/minute, and the duration of the flame is 60.26 minutes.