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"ABSTRAKThe study was concerned with the effects of the organic loading as food/microbe (F/M) and nitrogen concentration as BOD5: TN on the sequencing batch reactor (SBR) system efficiency and performance with 1:5 diluted-electroplating wastewater (EPWW) solutions. The results showed that chemical oxygen demand (COD) and biological oxygen demand (BOD5) removal efficiencies were almost the same with the organic loadings of 0.125-0.375 kg BOD5/m3.d. The CN- and Zn2+ loadings of 1.2-2.9 and 1.6-4.0 g/m3.d did not show strong repression effects to the COD and BOD5 removal efficiencies. In addition, the high Zn2+ removal efficiency level of 94-96% was detected. Moreover, the system did not show any difference in Zn2+ and COD removal efficiencies at the BOD5: TN ratios of 100:5-100:10. Urea and (NH4)2SO4 could be used as the nitrogen source of 1:5 diluted-electroplating wastewater solution. The highest COD, BOD5, Zn2+, CN-, Total Kjeldahl nitrogen (TKN) and total nitrogen (TN) removal efficiencies of 98.0±0.2, 97.0±0.7, 97.7±0.1, 93.3±1.2, 86.5±1.1 and 80.9±0.5%, respectively, were detected at the BOD5:TN ratio of 100:10 and (NH4)2SO4 was used as the nitrogen source. The system also showed good bio-sludge performance with the Sludge Volume Index (SVI) and Sludge Retention Time (SRT) values of 51±4 mL/g and 29±3 days, respectively."

"Sorbitan ester asam lemak merupakan surfaktan hasil esterifikasi sorbitan dengan asam lemak. Sorbitan stearat dan sorbitan oleat merupakan senyawa non-polar dan memiki gugus hidroksi sehingga berpotensi sebagai pengikat ion logam. Pada penelitian ini, disintesis sorbitan stearat dan sorbitan oleat dari sorbitol menggunakan katalis H2SO4 dan NaOH serta aplikasinya sebagai ligan terhadap ion logam Zn2 dan Pb2 pada sampel sludge Tegal. Sintesis sorbitan ester dilakukan melalui tahap dehidrasi dan tahap esterifikasi. Sorbitan ester hasil sintesis dikarakterisasi dengan FTIR dan ditentukan kadar asam lemak bebasnya. Studi pembentukan kompleks dilakukan dengan metode job menggunakan spektrofotometer UV-Vis. Konsentrasi ion logam yang terikat oleh ligan dianalisis menggunakan AAS. Sorbitan ester hasil sintesis diaplikasikan terhadap hasil destruksi basah sampel sludge Tegal dengan variasi pH dan volume larutan. Melalui penelitian ini berhasil disintesis sorbitan stearat dan sorbitan oleat dengan nilai asam 29,45 mg/g dan 65,92 mg/g serta kadar asam lemak bebas sebesar 14,94 dan 33,19 . Sorbitan stearat hasil sintesis memiliki kemampuan dalam mengikat ion logam yang paling baik dibandingkan sorbitan oleat dan Span 80 yaitu mampu mengikat 30,5 ion Zn2 dan 42 ion Pb2 dari larutan destruksi sampel sludge Tegal dengan waktu kontak 2 s, pH 1 dan perbandingan volume logam : ligan sebesar 2 : 1.

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Sorbitan fatty acid ester is a surfactant made from esterification reaction of sorbitan and fatty acid. Sorbitan stearate and sorbitan oleate have a potential as metal ligand due to their hydroxyl groups and because of their non polar properties. In this research, synthesis of sorbitan stearate and sorbitan oleate were carried out using sorbitol and catalyzed by H2SO4 and NaOH. Synthesis of both sorbitan esters were done in two steps, the first step was dehydration of sorbitol and then esterification. The products of the reaction were characterized using FTIR and the acid values were also evaluated. Later on, the sorbitan esters ability to bind with metal ions was studied using AAS to analyze the concentration of metal ion solution. The complex formation study was done with Job`s Method using UV Vis spectrophotometers. We also studied the use of sorbitan esters as ligand for metal ions in solution of industrial sludge from Tegal. The sorbitan ester products has acid values of 25,45 mg g and 65,9 mg g for sorbitan stearate and sorbitan oleate respectfully, with 14,94 and 33,19 free fatty acids. Compared to sorbitan oleate and Span 80, the sorbitan stearate product has the best potential to be use as ligand, as it can bind up to 30,5 of Zn2 ion and 42 of Pb2 ion from destruction solution of Tegal`s industrial sludge with the optimum condition contact time 2 s, pH 1, and metal ligand volume ratio is 2 1."

"Hipertensi merupakan masalah kesehatan yang prevalensinya masih tinggi di Indonesia. Mayoritas pengidap hipertensi mengandalkan obat golongan penghambat ACE (angiotensin-converting enzyme) sebagai terapi obat hipertensi mereka. ACE dapat dihambat dengan cara mengikat ion Zn2 atau asam amino pada situs aktif ACE. Penelitian sebelumnya menunjukkan bahwa ekstrak biji melinjo memiliki aktivitas penghambatan ACE secara in vitro. Dalam penelitian ini, dilakukan penambatan molekuler pada beberapa senyawa dalam ekstrak biji melinjo terhadap makromolekul ACE guna menganalisis senyawa mana dari dalam ekstrak biji melinjo tersebut yang memiliki aktivitas penghambatan ACE. Hasil penambatan molekuler dengan AutoDock4Zn menunjukkan bahwa resveratrol, gnetol, isorhapontigenin, gnetin c, trans-?-viniferin, gnemonol K, gnemonol M, dan aglikon gnemonosida B berpotensi memiliki aktivitas penghambat ACE. Beberapa ligan tersebut mampu berikatan dengan ion Zn2 melalui ikatan kation-phi. Selanjutnya, dilakukan simulasi dinamika molekuler pada ligan-ligan tersebut dalam rentang waktu 20 ns untuk menganalisis kestabilan ikatan ligan terhadap ion Zn2 dan ikatan ligan terhadap residu asam amino pada sisi aktif ACE. Berdasarkan hasil perhitungan nilai energi bebas ikatan dengan metode MM-GBSA dan MM-PBSA, gnetin C memiliki afinitas tertinggi terhadap ACE daripada ligan uji lain pada suhu 300 K, sedangkan pada suhu 310 K afinitas tertinggi dimiliki oleh gnemonol K.

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Hypertension is a health problem, in which the prevalence remains high in Indonesia. The majority of hypertensive patients rely on ACE angiotensin converting enzyme inhibitors as their drug therapy of hypertension. ACE catalytic mechanism can be inhibited by ligands via the zinc ion or amino acids interactions in the active site of ACE. Recent study demonstrated that melinjo seed extracts have ACE inhibitory activity in vitro. In this study, we conducted molecular docking of several substances extracted from melinjo seeds to analyze which substances have ACE inhibitory activity.

Molecular docking results using AutoDock4Zn indicated that resveratrol, gnetol, isorhapontigenin, gnetin C, trans viniferin, gnemonol K, gnemonol M and aglycone of gnemonosida B potentially have ACE inhibitory activity. Some of these ligands are able to bind zinc ion via cation pi interactions. We also conducted molecular dynamics simulations involving these ligands within 20 ns to analyze the stability of the interactions between zinc ligand and ligand amino acids in the active site. According to the binding free energy calculations using MM GBSA and MM PBSA methods, gnetin C showed the highest affinity for ACE among other ligands at a temperature of 300 K, while at a temperature of 310 K the highest affinity belongs to gnemonol K."