Helium: Journal of Science and Applied Chemistry

Optimization of Bacterial Cellulose-Quercetin Biocomposite Synthesis Using The Ex-Situ Method and Its Application as an Antibacterial Agent

Riza Apriani — 2025-06-04

Bacterial cellulose is a natural polymer synthesized by bacteria, possessing significant potential for biomedical and pharmaceutical applications. However, it lacks inherent antibacterial properties, necessitating modification with additional materials. Quercetin, a flavonoid compound, is known for its pharmacological activities, including antibacterial effects by disrupting bacterial cell walls. This study aims to identify the antibacterial activity of bacterial cellulose-quercetin biocomposite by optimizing the concentration and modification time, and to characterize their functional groups. Bacterial cellulose was modified using an ex-situ method by immersing it in quercetin solution. Antibacterial testing was performed using the disk diffusion method against Staphylococcus aureus and Escherichia coli. Results indicated that the optimal bacterial cellulose-quercetin biocomposite was achieved at a concentration of 6% with a modification time of 48 hours, showing excellent antibacterial properties with inhibition zones of 18.5 mm for S. aureus and 18 mm for E. coli. FTIR analysis confirmed the main functional groups of cellulose (O-H, C-H, and C-O-C glycosidic bonds) in both bacterial cellulose and the composite, showing no significant changes after immersion in distilled water. This suggests that quercetin binds strongly to the bacterial cellulose matrix, resulting in a stable biocomposite with potential as an effective antibacterial material, such as for wound healing.

Characterization of Simplicia, Extract, and Mineral Content of Broccoli (Brassica oleracea var. italica)

Bina Lohita Sari — 2025-06-05

Bioactive compounds and minerals in medicinal plants make them both therapeutic agents and raw materials for producing contemporary medications. Broccoli (Brassica Oleracea var Italica) is one of the possible therapeutic plants that features several nutrients that are high in minerals. This study produced Broccoli ethanol extract and characterized the water, ash, and phytochemical test of simplicia and extract. The mineral content of simplicia, such as calcium, potassium, sodium, and iron, used the flame test Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) method. This method is specifically for analyzing atomic elements or ions, which causes them to be excited and emit light at specific wavelengths. The result of water and ash content of Broccoli simplicia and ethanol extract within a range of values 2-9 – 5.8 %. Positive results for alkaloids, flavonoids, saponins, and tannins in phytochemical tests of simplicia and ethanol extract. The mineral content showed that calcium, potassium, sodium, and iron were 109.52 ± 0.25 mg/100 g, 375.58 ± 0.81 mg/100 g, 9.54 ± 0.092 mg/100 g, and 1.93 ± 0.00 mg/100g, respectively. It was concluded that as a natural ingredient, broccoli contains higher potassium than other minerals, and secondary metabolites in simplex and ethanol extracts have health benefits.

Targeting Dopamine Transporter (DAT) with Peronema canescens Bioactives: A Molecular Docking Study for Stroke-Related Pain and Sedation Management

Rizki Rachmad Saputra — 2025-06-07

Pain and drowsiness are common symptoms of stroke recovery, which can be difficult to manage owing to neurochemical abnormalities in the dopamine system. The Dopamine Transporter (DAT) controls dopamine levels, which influences pain perception and neurological recovery. This study examines bioactive chemicals found in Peronema canescens leaves and their possible interactions with DAT. AutoDock Vina was used to perform molecular docking simulations to determine the binding affinities of Peronemin derivatives (A2, A3, and B2) to the Dopamine Transporter (DAT). The receptor structure (PDB ID: 4M48) was created by eliminating water molecules, introducing polar hydrogens, and optimizing the structure using AutoDockTools. Ligand structures were translated to the proper format, and docking was conducted using a grid box centered on DAT's active site, with an exhaustiveness value of 10. The Peronemin derivatives A2, A3, and B2 demonstrated binding affinities stronger than nortriptyline, native ligand (−10.6, −10.5, and −10.3 kcal/mol, respectively) and binding similarities ranging from 72.2% to 94.4%. These findings suggest that Peronema canescens bioactives may be promising candidates for stroke-related pain and sedative control, warranting further experimental validation.

The Catalytic Performance of MnSO4-Doped Natural Zeolite in Ethyl Acetate Synthesis

Adelia Natasya Regita Nugroho — 2025-07-06

Ethyl acetate is a compound that is widely used across various industries. However, its esterification process typically requires a catalyst to improve reaction efficiency. This study focuses on developing a MnSO₄-doped natural zeolite catalyst using the impregnation method to enhance its catalytic activity in the esterification of acetic acid and ethanol. The synthesized catalyst was characterized using FTIR, XRD, and SEM-EDS to analyze structural and morphological changes. FTIR characterization revealed the presence of Si-O-Si and Al-O-Si bonds in the 1000 to 1100 cm^-1 region, while XRD confirmed that the zeolite with transition metal impregnation shows a decrease in the intensity of the diffraction peak. SEM-EDS analysis demonstrated that the MnSO₄-doped natural zeolite exhibited a more uniform morphology, with manganese ions effectively integrated into the surface and pores of the zeolite. Additionally, EDS measurements detected the presence of elements such as Si, O, Al, Na, and Mn, confirming the successful modification of the zeolite to act as a catalyst. Catalytic testing showed that the highest ethyl acetate conversion achieved was 91.27% within 90 minutes, with optimal performance observed at a catalyst mass of 1 g. These findings indicate that modifying zeolite with MnSO₄ can significantly enhance catalyst performance in esterification reactions, making it a more efficient and sustainable alternative to conventional catalysts.

The Potential of Isoniazid Derivatives as Anti-Tuberculosis Drugs targeting 6MA8: In Silico Study

Muhammad Yogi Saputra — 2025-07-07

Tuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis. Isoniazid, a synthetic antimicrobial agent, remains one of the most crucial first-line medications in TB therapy. Enhancing TB treatment strategies can be achieved through structural modifications of existing drugs. This study investigates the potential of isoniazid derivatives as anti-tuberculosis agents targeting the CYP3A4 protein complexed with a small-molecule inhibitor (PDB ID: 6MA8) and evaluates their toxicity profiles using in silico methods. The ligands analyzed include isoniazid derivatives 1–5, with isoniazid as a reference compound and protoporphyrin as the native ligand. The structure of ligands was prepared using Avogadro software and optimized with ORCA software. The crystal structures of 6MA8 were retrieved from the PDB database and further validated using YASARA. In silico methods such as molecular docking and ProTox prediction were employed to evaluate the potential of these isoniazid derivatives as anti-TB drugs. The interactions were visualized using Biovia Discovery to assess the interaction between the isoniazid derivatives and the receptor. The results showed derivative 4 exhibited the lowest binding affinity (-71.56 kcal/mol) compared to isoniazid (-65.90 kcal/mol), derivative 1 (-63.65 kcal/mol), derivative 2 (-67.01 kcal/mol), derivative 3 (-67.37 kcal/mol), derivative 5 (-69.02 kcal/mol), and native ligand (-182.68 kcal/mol). Biovia Discovery Studio simulations indicated that the isoniazid derivatives interacted with 6MA8 via conventional hydrogen bonds, carbon-hydrogen bonds, and other interactions. The toxicity analysis showed that the derivatives had safe LD50 values, supporting their safety profiles. These results suggest that isoniazid derivatives have promising potential as anti-tuberculosis agents targeting 6MA8.

Combination of Coagulation and Fermentation Technology in Utilizing Liquid Tofu Waste into Liquid Organic Fertilizer for the Growth of Chinese Spinach (Amaranthus dubius) Plants

Nina Arlofa — 2025-07-07

Wastewater is known to contain organic compounds, such as proteins, fats, and carbohydrates, which can be utilized more effectively through technology, coagulation, and fermentation, allowing it to be used as an organic liquid fertilizer (OLF), a more environmentally friendly option. Research objectives are to determine the influence of powder seed sour Java as a coagulant on lower COD and BOD levels, the effect of adding EM4 to nutrients in waste liquid, and the impact of POC on the growth of spinach China (Amaranthus dubius). This research is conducted through the process of coagulation and flocculation using a solution seed powder of sour Java with varying concentrations of 500, 1000, 1500, 2000, and 2500 ppm. The concentration of 1500 ppm has resulted in the lowest COD and BOD levels, respectively, 250 ppm and 127 ppm. The solution with the lowest COD and BOD levels is fermented using EM4 with variations of 0, 0.5, 1, 1.5, and 2mL. The addition of EM4 is expected to accelerate the fermentation process and enhance the availability of beneficial nutrients, including N, P, and K, for plant growth and development. The total content of N, P, and K is highest, at 2.087%, following the addition of 1 mL of EM4 to 150 mL of the sample. POC with the addition of 1 mL of EM4 was applied to the spinach plant in China, resulting in a plant 25 cm tall, with nine leaves, and a total fresh weight of 39 grams.