Judul: Utilization of Lignin from Black Liquor of Waste Paper Industry as Antimicrobial in Food Packaging
Abstrak: Lignin merupakan polimer kimia alami yang belum dimanfaatkan dengan baik dan berpotensi sebagai agen antimikroba karena mengandung senyawa fenolik. Tujuan penelitian ini memanfaatkan lignin dari lindi hitam sebagai agen antimikroba yang diaplikaskan pada biofilm untuk kemasan pangan. Lignin diperoleh dari proses isolasi lindi hitam menggunakan asam encer melalui enam kali pencucian. Lignin hasil isolasi dilakukan pengujian karakteristik fisik, seperti kadar air, kadar abu, kadar kemurnian lignin, FTIR, DSC, TGA, dan aktivitas antimikroba. Biofilm lignin diuji karakteristik fisik, mekanik, dan aktivitas antimikroba. Hasil penelitian menunjukkan rendemen isolat lignin 34,45%. Kadar air lignin sebesar 10,28%, dan kadar abu sekitar 1.06%, dengan kadar kemurnian lignin 103,49%. Degradasi termal lignin terjadi pada suhu 340 oC, dan Tg 2 terjadi pada suhu 166 oC. Karakteristik gugus fungsi lignin yaitu terdapat senyawa fenolik-siringil, guaiasil, dan eter. Aktivitas antimikroba lignin yang terbaik yaitu pada konsentrasi 0.1 g/mL dengan pelarut ethanol-air dan 0.4 g/mL dengan DMSO. Biofilm lignin rheomix pada konsentrasi 2% secara keseluruhan memiliki karakteristik fisik dan mekanik, serta dapat menghambat pertumbuhan bakteri uji yang lebih baik dibanding metode pelarutan., Lignin is a natural chemical polymer that has not been utilized properly and has the potential as an antimicrobial agent because it contains phenolic compounds. The purpose of this study was to utilize lignin from black liquor as an antimicrobial agent which was applied to biofilms for food packaging. Lignin was obtained from the black liquor isolation process using dilute acid through six washings. The isolated lignin was tested for physical characteristics, such as moisture content, ash content, lignin purity, FTIR, DSC, TGA, and antimicrobial activity. Lignin biofilms were tested for physical, mechanical, and antimicrobial activity characteristics. The results showed that the lignin isolate yield was 34.45%. The lignin water content is 10.28%, and the ash content is about 1.06%, with a lignin purity level of 103.49%. Thermal degradation of lignin occurs at a temperature of 340 oC, and Tg 2 occurs at a temperature of 166 oC. The characteristics of the lignin functional group are phenolic-syringyl, guaiacil, and ether compounds. The best antimicrobial activity of lignin was at a concentration of 0.1 g/mL with ethanol-water and 0.4 g/mL with DMSO. The rheomix lignin biofilm at a concentration of 2% overall has physical and mechanical characteristics, and can inhibit the growth of test bacteria better than the dissolving method.Lignin is a natural chemical polymer that has not been utilized properly and has the potential as an antimicrobial agent because it contains phenolic compounds. The purpose of this study was to utilize lignin from black liquor as an antimicrobial agent which was applied to biofilms for food packaging. Lignin was obtained from the black liquor isolation process using dilute acid through six washings. The isolated lignin was tested for physical characteristics, such as moisture content, ash content, lignin purity, FTIR, DSC, TGA, and antimicrobial activity. Lignin biofilms were tested for physical, mechanical, and antimicrobial activity characteristics. The results showed that the lignin isolate yield was 34.45%. The lignin water content is 10.28%, and the ash content is about 1.06%, with a lignin purity level of 103.49%. Thermal degradation of lignin
Keyword: antimicrobial, biofilm, black liquor, lignin, starch

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: Implementation of Spatio-Temporal Change Query in Relational Database.
Abstrak: Geographic object changes in various views. Object changes are recorded using a model of static storage. No historical connection between old version data and new version data has been built. For that, a storage model of spatio-temporal queries that can analyze spatio-temporal changes has been developed. The object changes the geometry are grouped according to the taxonomy of Spatio-Temporal Pattern Change. This research has been able to apply the query patterns change including born, expand, merge, contract, split, normal and die. This query based on geometric (area) changes. The implementation of spatio-temporal change queries represents an object changes continuously with easy, change detection is done by comparing two versions of data. Keyword: spatio-temporal change query, spatio-temporal change pattern.
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