Judul: Utilization of Lignin as an Antimicrobial Agent in Rami Fabrics to Support the Development of Personal Protective Equipment
Abstrak: Lignin merupakan bahan fenolik yang berpotensi sebagai antimikroba. Penelitian ini bertujuan memanfaatkan lignin menjadi bahan antimikroba yang diaplikasikan pada kain rami sebagai dasar ilmiah untuk pengembangan APD. Lignin diperoleh dari lindi hitam yang diisolasi menggunakan asam encer melalui isolasi 1 tahap dan 2 tahap serta diuji karakteristik ligninnya. Kemudian, lignin diaplikasikan pada kain rami dengan metode sonikasi dan diuji aktivitas antimikroba dengan metode difusi agar terhadap bakteri gram-positif yaitu Propionibacterium acne, Staphylococcus aureus, Bacillus subtilis, dan Staphylococcus epidermidis. Hasil penelitian menunjukkan bahwa isolat lignin 1 maupun 2 menghasilkan rendemen sekitar 28% dan memiliki karakteristik lignin berdasarkan analisis-analisis yang dilakukan. Aktivitas antimikroba meningkat seiring dengan meningkatnya konsentrasi lignin. Nilai zona hambat tertinggi terjadi pada lignin 1 tahap konsentrasi 0,3 g mL-1 dan kain L2 terhadap bakteri Bacillus subtilis. Penambahan bahan HDTMS merubah kain menjadi lebih hidrofobik, namun, menutupi sifat antimikroba pada kain lapis lignin., Lignin is a phenolic substance that has the potential as an antimicrobial agent. This study aims to utilize lignin as an antimicrobial agent that is applied to rami fabric as a scientific basis for the development of PPE. Lignin was obtained from black liquor isolated using dilute acid through 1 and 2 steps and the characteristic of lignin was tested. Lignin was applied to the fabric by sonication method and tested for antimicrobial activity using the agar diffusion method were performed on gram-positive bacteria is Propionibacterium acne, Staphylococcus aureus, Bacillus subtilis, dan Staphylococcus epidermidis. The results showed that the yield of lignin 1 and 2 isolate about 28% and had lignin characteristics based on analyzed carried out. The antimicrobial activity increased with the increase in lignin concentration. The highest inhibition zone occurred at lignin 1 step with a concentration of 0,3 g mL-1 and L2 fabric against Bacillus subtilis bacteria. The addition of HDTMS material changed the fabric to be more hydrophobic, however, covering the antimicrobial properties of the lignin-coated fabric.
Keyword: antimikroba, isolasi lignin, kain rami, lignin, lindi hitam, antimicrobial, black liquor, lignin, lignin isolation, rami fabric

Judul: Fraksinasi Lignin dan Aplikasinya pada Kain sebagai Agen Antibakteri
Abstrak: Lignin mengandung gugus hidroksil fenolik yang dapat digunakan sebagai zat antibakteri alami. Berdasarkan penelitian sebelumnya, lignin memiliki sifat antibakteri yang baik pada bakteri gram positif. Akan tetapi, struktur lignin yang kompleks, heterogen, dan hidrofobik menyebabkan sulitnya aplikasi tersebut. Oleh karena itu penelitian ini bertujuan menghasilkan lignin yang bersifat hidrofilik dengan aktivitas antibakteri yang tinggi. Selain itu, penelitian ini bertujuan untuk menganalisis pengaruh tawas terhadap ketahanan sifat antibakteri kain berlapis lignin setelah pencucian. Pada penelitian ini, fraksinasi organosolv kayu Acacia crassicarpa menggunakan pelarut aseton, air, dan n-heksan. Kelarutan lignin diuji untuk mengetahui sifat hidrofiliknya. Kemudian sifat kimia lignin terfraksinasi diuji dengan FTIR, Py-GCMS, TGA, DSC, dan total phOH. Sedangkan aktivitas antibakteri dievaluasi dengan metode difusi agar terhadap bakteri S.aureus, S. epidermidis, P. acnes, dan B. subtilis. Aplikasi lignin pada kain rami menggunakan tawas sebagai agen pengikat silang. Hasil penelitian menunjukan bahwa fraksinasi organosolv mengahasilklan lignin bersifat lebih larut air dengan nilai kelarutan sebesar 70%, S/G rasio 1,56 dan total phOH 12,12 mmol/g. Total phOH dan S/G rasio diduga berkorelasi positif dengan aktivitas antibakteri sehingga memiliki nilai zona bening yang lebih besar (0,8-1,4 cm). Selain itu, kain berlapis lignin organosolv yang telah di cuci memiliki ketahanan terhadap bakteri uji dengan nilai rata-rata diameter zona bening sekitar 0,1-0,4 cm., Phenolic hydroxyl groups found in lignin can be employed as organic antibacterial agents. According to earlier studies, lignin effectively combats gram positive bacteria. However, the application is challenging due to the lignin's complicated, heterogeneous, and hydrophobic structure. As a result, the goal of this project is to create hydrophilic lignin with strong antibacterial properties. The study also seeks to examine how alum affects the durability of the antibacterial capabilities of lignin-coated fabrics after washing. In this study, acetone, water, and n-hexane were utilized as solvents for the organosolv fractionation of Acacia crassicarpa wood. Testing the solubility of lignin revealed that it is hydrophilic. Following that, FTIR, Py-GCMS, TGA, DSC, and total phOH were used to examine the chemical characteristics of fractionated lignin. The agar diffusion method was used to assess the antibacterial activity in the meantime against the bacteria S. aureus, S. epidermidis, P. acnes, and B. subtilis. applying lignin using alum as a crosslinking agent to hemp textiles. According to the findings, lignin generated through organosolv fractionation is more water soluble, having a solubility value of 70%, a S/G ratio of 1,56, and a total pH of 12,12 mmol/g. They have a higher clear zone value because total phOH and S/G ratios are believed to have a favorable link with antibacterial activity (0,8-1,4 cm). Additionally, the textiles coated with lignin and treated with organosolv demonstrated resistance to the test microorganisms with an average clear zone diameter of between 0,1 cm and 0,4 cm.
Keyword: antibacterial, clear zone, fractionation, lignin, organosolv

Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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