Judul: Literature Study on the Synthesis of Fatty Acid Ester of Hydroxy Fatty Acid (FAHFA) and Their Characterizations
Abstrak: Senyawa fatty acid ester of hydroxy fatty acid (FAHFA) merupakan senyawa turunan lipid yang ditemukan pada tahun 2014 dalam jaringan adiposa mencit. Struktur dari senyawa yang diketahui memiliki aktivitas antidiabetes dan antiinflamasi tersebut terdiri atas rantai asam lemak dan hidroksi asam lemak. Sintesis berbagai kelompok senyawa FAHFA telah banyak diupayakan. Material awal yang dapat digunakan dalam jalur sintesis senyawa tersebut antara lain senyawa aldehida, epiklorohidrin, bentuk enol dan alkuna, α,ω-diol, dan metil ester asam lemak. Material awal perlu dipilih berdasarkan kelompok dan jenis regioisomer dari senyawa FAHFA yang akan disintesis. Hasil karakterisasi senyawa menggunakan spektroskopi inframerah dan resonans magnetik inti menunjukkan sinyal khas dari gugus karboksilat serta ikatan ester yang menghubungkan dua rantai asam lemak penyusun. Sinyal khas lain yang berasal dari gugus olefin terdapat pada senyawa FAHFA dengan rantai takjenuh., The fatty acid ester of hydroxy fatty acid (FAHFA) compound is a lipid derivative compound that was discovered in 2014 in the adipose tissue of mice. The structure of the compound which is known to have antidiabetic and anti-inflammatory activity consists of fatty acid and hydroxy fatty acid chains. Many attempts have been made to synthesize various groups of FAHFA compounds. The starting materials that can be used in the synthesis pathway of these compounds include aldehydes, epichlorohydrin, enol, and alkyne forms, diols, and fatty acid methyl esters. The starting material needs to be selected based on the group and type of regioisomer of the FAHFA compound to be synthesized. The results of the characterization of compounds using infrared spectroscopy and nuclear magnetic resonance showed a typical signal from the carboxylate group and the ester bond connecting the two constituent fatty acid chains. Another characteristic signal from the olefin group is found in FAHFA compounds with unsaturated chains
Keyword: FAHFA, fatty acid ester of hydroxy fatty acid, lipid, synthesis

Judul: Sintesis Surfaktan Alkanolamida (FADEA) dari Minyak Kelapa dan Dietanolamina Berbantuan Mikrogelombang
Abstrak: Surfaktan FADEA (Fatty Acid Diethanolamide) merupakan surfaktan nonionik yang diperoleh dari reaksi amidasi dengan proses pemanasan konvensional. Dalam penelitian ini, FADEA diperoleh dari minyak kelapa serta dietanolamina dengan perlakuan mikrogelombang sebab dinilai lebih aman, memiliki homogenitas suhu tinggi, pemanasan selektif, dan mempercepat waktu reaksi. Surfaktan FADEA berhasil terbentuk pada perbandingan 1:1, 1:2, dan 1:3 (b/b) waktu reaksi 15–25 menit dengan daya medium (60%P). Hasil spektrum FTIR menunjukkan FADEA telah terbentuk, namun masih belum terkonversi secara optimal karena masih terdapat puncak trigliserida dan dietanolamina. Karakteristik kimia, seperti nilai pH dan ALB (Asam Lemak Bebas) dari 6 produk FADEA telah memenuhi spesifikasi. Namun, DEA bebas dan total amida tidak memenuhi spesifikasi. Dari penelitian ini, surfaktan FADEA pada perbandingan 1:3 dalam waktu 25 menit memiliki karakteristik dan kinerja terbaik. Surfaktan FADEA mampu menurunkan tegangan permukaan air dari 70,9 dyne/cm menjadi 24–29 dyne/cm. Stabilitas busa semakin tinggi dengan meningkatnya perbandingan massa dan waktu reaksi, sebesar >87%., FADEA surfactant is a non-ionic surfactant obtained from an amidation reaction with a conventional heating process. In this study, FADEA was obtained from coconut oil and diethanolamine with microwaves treatment because it is considered safer, has high-temperature homogeneity, selective heating, and speeds up reaction time. FADEA surfactant was successfully formed at a ratio of 1:1, 1:2, and 1:3 w/w in a reaction time of 15–25 minutes at medium power (60%P). The results of the FTIR spectrum showed that FADEA has been formed, but hadn’t optimally converted because there were still triglyceride and diethanolamine peaks. Chemical characteristics, such as pH and ALB values of 6 products that fulfilled the specifications. However, free DEA and total amide values didn’t fulfil the specifications. From this study, FADEA surfactant at ratio of 1:3 in 25 minutes had the best characteristics and performance. FADEA surfactant is able to reduce the surface tension of water from 70,9 dyne/cm to 24–29 dyne/cm. Foam stability was higher with increasing mass ratio and reaction time, by >87%.
Keyword: coconut oil, FADEA, microwave, surfactant

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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