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Methylene blue is a popular dye used in the batik industry; however, it potentially causes environmental problems in view of the residual MB content in the liquid waste, which is difficult to naturally degrade. This study aimed to synthesize Fe3O4-TD using tea dregs from household waste and its application as an adsorbent for methylene blue dye. The synthesis was carried out using the reverse co-precipitation method with water as a solvent at room temperature. Fe3O4-TD characterization using FTIR, XRD, and PSA. The adsorption of methylene blue (MB) on Fe3O4-TD was studied at various pH MB, reaction time, and concentration MB to determine the kinetic model and MB adsorption isotherm on Fe3O4-TD and the interactions that occur between MB and Fe3O4-TD. FTIR spectra and X-Ray diffractogram showed that the magnetite formed in a pure state did not mix with other iron oxides. The crystal and particle size of Fe3O4-TD is 18.92 nm and 26.70 µm, respectively. MB adsorption on Fe3O4-TD occurred well at pH > 3 and followed the Ho' pseudo-second-order kinetics model and the Freundlich isotherm model. The interactions between MB and Fe3O4-TD through electrostatic interactions, hydrogen bonds, and phi-phi interactions.

Lupane-type triterpenoid saponins are potent plants' secondary metabolites for drug development as they showed various activities such as anticancer, Sarcoplasmic Reticulum Ca 2+ -ATPase (SERCA) activator which is very important for neurons, and antileishmanial. The triterpenoid saponin backbone is produced by cyclization and rearrangement of the 2,3-oxidosqualene precursor by the oxidosqualene cyclase. The type of oxidosqualene cyclase involved determines the type of saponins so it is referred to as a key enzyme. Lupane-type saponins are produced by 2,3-oxidosqualene cyclization through the chair-chair-chair conformation and the formation of various cation intermediates. This study aimed to analyze lupeol synthase, the key enzyme which determines the conversion of 2,3-oxidosqualene into lupane-type saponins. This in silico project was done using bioinformatics programs including Multiple Em for Motif Elicitation (MEME), ProtParam, and Molecular Evolutionary Genetic Analysis (MEGA-X) for relationship analysis. The amino acid sequences analysis using the MEME program showed that lupeol synthase has QW, DCTAE, and CYCR conserved motifs in the oxidosqualene cyclase family even though some evolutions were also present. Analysis of chemical and physical parameters with ProtParam indicated that lupeol synthase had lower stability than lanosterol synthase from Saccharomyces cerevisiae. The phylogenetic tree showed that lupeol synthase was closely related to other plant oxidosqualene cyclases. The results of this study are expected to support the modification strategy determination to increase the production of lupane-type saponins using a biotechnological approach in the pharmaceutical industry.

The writing of this article contains an overview of the important role played by guidance and counseling teachers during covid-19. With the aim of finding a bright spot on the problems experienced by students during online learning. Given that some activities outside the home are limited, researchers have the opportunity to use the literature study method. Techniques for collecting data are sufficient by reviewing book references, journal articles and social media if necessary. From the data that has been collected, the next step is to analyze it so that conclusions can be easily drawn. Building communication and friendship between teachers and parents allows a counseling guidance teacher to have an idea of how to create an online learning atmosphere that is not boring. So that students will be enthusiastic and enthusiastic in participating in these activities.Keywords: teacher role, guidance and counseling, online learning