Ants Density of Odontomachus sp. and Its Ecological Role in Kendari City Green Open Space

The degradation of environmental quality has become a global problem today. One way to address this is by providing green open spaces that help maintain environmental quality. Kendari city has a number of green open spaces (RTH) including, RTH in Baruga sub-district, Kendari mayor's office area and in Nanga-nanga botanical garden of Kendari city. This study aims to determine the density and ecological role of ants (Odontomachus sp.) in green open spaces in Kendari city. The method used in this study was hand sorting using ring samples with a diameter of 20 cm and a height of 15 cm in a plot measuring 25 m x 25 m consisting of 25 sampling points with a distance of 5 m per point. Data analysis was carried out by calculating the density at each research location, namely Baruga green space, mayor's park and Nanga-nanga botanical garden. The results showed that the highest density of ants (Odontomachus sp.) was found in the mayor's park with 16 ind/m2. The ecological role of ants (Odontomachus sp.) in Kendari city green open space is an important role in bioturbation and natural predators of soil fauna such as termites and earthworms

Phytoremediation of nickel by Paraserianthes falcataria with varying levels of manure

The objective of this study were to identify effective variations in fertilizer doses for phytoremediation of heavy metal nickel (Ni) by using sengon plants (Paraserianthes falcataria) before being used for post-mining land reclamation. This research is an experimental study, the growth parameters measured include plant height, number of leaves, root length, and plant biomass. The data obtained were analyzed using analysis of variance (ANOVA) and continued with Duncan's test. The manure used consists of chicken manure, calcium carbonate, and rice bran. Variation in fertilizer dose is the ratio between manure to mine soil 40:60 (A), 50:50 (B), 60:40 (C), 70:30 (D), and control without fertilizer (E) with four repetitions time. The results showed that there was a significant difference between the concentration of nickel content before and after the treatment of fertilizer dosing (p>0.05), which means that the dose of fertilizer can affect plant growth and phytoremediation abilities. The dose of D fertilizer (70:30) is the most suitable for phytoremediation of heavy metal nickel (Ni) because it shows the highest heavy metal concentration in the roots, which is 3.2 ppm. The plant growth parameters measured showed that the dose of fertilizer B (50:50) was most suitable for increasing plant height and biomass (P. falcataria) with a plant height of 27 cm and a biomass of 0.9 g/m2. The dose of C fertilizer (60:40) is most suitable for increasing the number of leaves with an average of 111.5 leaves. Control without fertilizer (E) is most suitable for increasing the root length of P. falcataria. Thus, the addition of manure affects the growth of P. falcataria, and nickel phytoremediation using P. falcataria at the dose of manure D (70:30) can reduce the nickel content in the soil

Synthesis of Glucopyranosyl Acetic from Sago Flour as Raw Material for the Synthetic Polymers

Synthesis of glucopyranosyl acetic from sago flour as raw material for the synthetic polymers has been successfully carried out. The synthesis product is obtained through two reaction stages, namely the hydrolysis and esterification reactions. Sago flour is hydrolyzed with 25% HCl and neutralized with 45% NaOH. Glucose hydrolysis of sago starch and acetic anhydride was esterified using a zinc chloride catalyst. Synthesis product was obtained as a white solid substance (57.31% recovery), a melting point of 110 - 111oC, and Rf 0.79 on TLC (SiO2, n-hexane: ethyl acetate = 9:1 v/v). The results of the analysis of synthesis products with FTIR and GC-MS spectrometers showed that the synthesis product was glucopyranosyl acetic or 2,3,4,6-tetra-O-acetyl glucopyranose

Biosynthesis of Methyl Esters from Used Cooking Oil (UCO) using Lipase Enzyme from Aspergillus oryzae on Moldy Copra

The successful production of methyl esters from used cooking oil (UCO) using lipase enzymes from Aspergillus oryzae on moldy copra has been achieved. This method offers an eco-friendly substitute for crude palm oil (CPO) in generating methyl esters or biodiesel, contributing to waste reduction, economic benefits, and lowered greenhouse gas emissions for sustainable development. This study aimed to synthesize methyl esters from UCO using the Aspergillus oryzae lipase enzyme sourced from moldy copra. The enzyme was purified through ammonium sulfate fractionation and gel filtration column chromatography. Electrophoresis validated its purity, and activity was assessed through the Erdmann and Lowry method. Methyl ester synthesis involved transesterification with a UCO (1 mol): methanol (9 mol): lipase enzyme (15% v/v) ratio. The enzyme displayed notable characteristics, including 43.76 units/mg protein activity, a 41.7 kDa molecular weight, optimum pH of 8.2, temperature preference of 35°C, Km of 0.046, and a 1.926 µmol/minute Vmax. This enzyme efficiently catalyzed UCO (triolein) into methyl ester (methyl oleate), yielding 75.65%. Characterization using Fourier Transform Infrared (FTIR) revealed specific functional groups like –OH carboxylic acid, C=C alkenes, C=O esters, methyl (CH3-), and methylene (-CH2-). Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified prominent compounds: methyl palmitate (12.53%), methyl vacsenate (16.44%), and, notably, methyl oleate (41.08%). This underscores the potential of Aspergillus oryzae lipase as an effective biocatalyst for UCO transesterification, yielding valuable methyl esters or biodiesel

Synthesis of Ionophore from p-t-Butyl-(carboxymethoxy)calix[4]arene Substituted Amide

The ionophore has been successfully synthesized from p-t-butyl(carboxymethoxy)calix[4]arene subtituted amide. The ionophore was obtained in two steps of the synthesis reaction. The first step is the chlorination reaction of p-t-butyl(carboxymethoxy)calix[4]arene with thionyl chloride in dry benzene solvent. The product of the chlorination reaction is p-t-butyl(chloroacetylmethoxy)calix[4]arene in the form of the light brown viscous liquid with the rendemen of 78.25% and TLC (SiO2, CH3OH : CH2Cl2 = 1 : 1 v/v, Rf = 0.65). The second step is the amidation reaction of p-t-butyl(chloroacetylmethoxy) calix[4]arene with dimethylamine in dry tetrahydrofuran solvent. The product of the amidation reaction is p-t-butyl(dimethylcarbamoylmethoxy)-calix[4]arene or the DIMECAC4ND3 ionophore in the form of white solid with the rendemen of 60.75%, a melting point of 277-279 °C, and TLC (SiO2, CH3OH : CH2Cl2 = 1 : 1 v/v, Rf = 0.82)

Antituberculosis Activity Test of N-p-Methylbenzyl-p-coumaramide (MBC) Against M. tuberculosis H37Rv

An antituberculosis activity test of N-p-Methylbenzyl-p-coumaramide (MBC) against M. tuberculosis H37Rv has been carried out. The purpose of this study was to determine the antituberculosis activity of MBC against M. tuberculosis H37Rv. The study was conducted using agar diffusion method. The test solution was prepared by dissolving MBC in 20 mL Ogawa medium to a final concentration of 0.25; 0.50; 1; and 2 mg/L. PDA media that had been inoculated with M. tuberculosis H37Rv (seeded agar) were poured over the base layer on the petridish surface. Paper disks that have been immersed in the test solution were put symmetrically on the seeded agar. Furthermore, the seeds were incubated at 37 oC for 48 hours. Then the diameter of the inhibition zone was measured to the accuracy of 0.5 mm with a ruler. The results showed that MBC has biological activity as an antituberculosis. MBC can inhibit the growth of M. tuberculosis H37Rv at a concentration of 0.25; 0.50; 1; and 2 mg/L with a diameter of inhibitory zones respectively 8.9; 13.7; 18.5; and 21.3 mm. This showed that the inhibition of MBC on the growth of M. tuberculosis H37Rv increased with increasing concentration of MBC used

Extraction of The Chemical Components of Dengen Leaves (Dillenia serrata Thunb) by MAE Method and Activity Test as Antioxidant and Toxicity

Research on the extraction of chemical components of Dengen (Dillenia serrata Thumb) leaves using the MAE (microwave-assisted extraction) method and activity as an antioxidant and toxicity test has been carried out. This study aimed to extract the chemical components of Dengen leaves using the MAE method and to test the antioxidant activity and toxicity of the ethanol extract of Dengen leaves. The chemical components of Dengen leaves were extracted by the MAE method and obtained ethanol extract with a yield of 47%. Dengen leaves ethanol extract was partitioned with n-hexane and ethanol as solvents and obtained yields of 5% (n-hexane) and 65% (ethanol). The chemical components of Dengen leave ethanol extract were identified by phytochemical screening. The results of phytochemical screening showed the presence of secondary metabolites of alkaloids, flavonoids, saponins, polyphenols, terpenoids, and steroids. The antioxidant activity test of the ethanol extract of Dengen leaves was carried out using the DPPH (2,2-diphenyl-1-picrihydrazil) method and obtained the value of IC50 = 100,363 ppm (strong antioxidant). A toxicity test of the ethanol extract of Dengen leaves was carried out using the BSLT (Brine Shrimp Lethality Test) method and obtained the value of LC50 = 18.3443 ppm (very toxic)

Extraction of The Chemical Components of Dengen Leaves (Dillenia serrata Thunb) by MAE Method and Activity Test as Antioxidant and Toxicity

Research on the extraction of chemical components of Dengen (Dillenia serrata Thumb) leaves using the MAE (microwave-assisted extraction) method and activity as an antioxidant and toxicity test has been carried out. This study aimed to extract the chemical components of Dengen leaves using the MAE method and to test the antioxidant activity and toxicity of the ethanol extract of Dengen leaves. The chemical components of Dengen leaves were extracted by the MAE method and obtained ethanol extract with a yield of 47%. Dengen leaves ethanol extract was partitioned with n-hexane and ethanol as solvents and obtained yields of 5% (n-hexane) and 65% (ethanol). The chemical components of Dengen leave ethanol extract were identified by phytochemical screening. The results of phytochemical screening showed the presence of secondary metabolites of alkaloids, flavonoids, saponins, polyphenols, terpenoids, and steroids. The antioxidant activity test of the ethanol extract of Dengen leaves was carried out using the DPPH (2,2-diphenyl-1-picrihydrazil) method and obtained the value of IC50 = 100,363 ppm (strong antioxidant). A toxicity test of the ethanol extract of Dengen leaves was carried out using the BSLT (Brine Shrimp Lethality Test) method and obtained the value of LC50 = 18.3443 ppm (very toxic)

Pengaruh Model Problem Based Learning Terhadap Hasil Belajar Siswa pada Materi Sistem Imun di SMA Negeri 6 Kendari

Artikel ini bertujuan untuk mengetahui pengaruh hasil belajar kognitif siswa sesudah diajar dengan menggunakan model problem based learning pada materi sistem imun di SMA Negeri 6 Kendari. Jenis penelitian ini ialah penelitian kuantitatif, dengan metode penelitian quasi eksperimen. Teknik analisis data dilakukan dengan menggunakan analisis deskriptif dan analisis inferensial. Sampel pada penelitian ini yaitu kelas XI MIPA 5 (kelas eksperimen) dan kelas XI MIPA 6 (kelas kontrol), masing-masing sebanyak 20 siswa. Teknik pengambilan sampel dilakukan dengan menggunakan teknik purposive sampling. Hasil penelitian menunjukkan bahwa terdapat perbedaan yang signifikan antara hasil belajar kognitif siswa sesudah diajar menggunakan model problem based learning dan sesudah diajar menggunakan model konvensional pada materi sistem imun di SMA Negeri 6 Kendari, yaitu thitung 5,31 dan ttabel1,67 dengan taraf signifikansi 5%, sehingga thitung 5,31 > ttabel1,67 maka H0 ditolakdan Ha diterima.Kata Kunci: Hasil Belajar Kognitif, Model Problem Based Learning, Model Konvensional