The genus Psychotria is well known as a source of alkaloids and has contributed several novel indole-type alkaloids with quite a broad spectrum of bioactivities. This study was focused on identifying the alkaloids from the leaves of P. malayana Jack from Lombok island on the basis of Gas Chromatography-Mass Spectroscopy (GC-MS) data and the sample preparation followed acid-base extraction. The study showed that the major alkaloid contained by the leaves was hodgkinsine and other minor compounds, namely calycanthine, chimonantine, 2-ethyl-6-methylpyrazine, and 3-methyl-1,2,3,4-tetrahydrogamma-carboline. Bioactivities of the compounds were also discussed.

Small protein tyrosine phosphatase (PtpA) of Mycobacterium tuberculosis is attributed to the development of latent tuberculosis infection, and hence bocomes an interesting target for drug development. In this communication, inhibition of PtpA by naturally occurring fatty acids cis-2 and trans-2-eicosenoic acid is investigated. Mtb PtpA was heterologously expressed in Escherichia coli, and the activity of PtpA was inhibited by cis-2 and trans-2 eicosenoic fatty acids. Both compunds showed strong inhibition of PtpA activity with IC50 at low micromolar concentration. As comparison, trans-11-eicosenoic acid only slightly inhibit PtpA. In silico analysis confirmed the inhibition of PtpB by cis-2-eicosenoic acid by formation of several hydrogen bonds. These findings show that cis-2 and trans-2 eicosenoic fatty acids are potential candidates for latent tuberculosis inhibitors.

This study aims to determine the the efficiency of corrosion inhibition of imidazole derivatives in carbon steel based on quantum chemical parameters. Density functional theory method was applied in this study. Corrosion inhibition efficiency values ​​are strongly influenced by substituent groups. Corrosion inhibition efficiency values ​​have a linear correlation with quantum chemical parameters. The amine substituent increased the value of corrosion inhibition efficiency, in contrast nitro group reduced the efficiency of corrosion inhibition. The predicted corrosion inhibition efficiency data of imidazole does agree with the experimental data.

Epoxidation is a reaction of a carbon double bond with active oxygen, which results in the addition of an oxygen atom, converting the original double bond into a three-membered epoxide (oxirane) ring. Generally, the raw material for making epoxy comes from petroleum. Nyamplung kernel oil is a non-edible oil that can be used as an alternative raw material for making epoxy derivatives. The purpose of this study was to determine the optimum conditions and characterization of epoxy materials. The fatty acids of Nyamplung kernel oil were reacted formic acid and hydrogen peroxide with sulfuric acid as a catalyst. The optimum condition of the following parameters on the study of this process was investigated: the epoxidation time, temperature, and the mole ratio of formic acid and hydrogen peroxide. The results showed that the optimum reaction conditions with the temperature was 65 oC, the mole ratio of formic acid and hydrogen peroxide was 1:6, and the reaction time was 75 minutes. The results of the characterization under optimum conditions showed the oxirane value of 1.69, the iodine number of 9.63 mg iod/100 g, and the epoxy conversion of 67.6 %. The results of FTIR characterization showed absorption at a wavenumber of 820.03 cm-1 which is a specific absorption from the oxirane ring of the epoxy compound.

Abstrak: Peningkatan Sumber Daya Manusia dalam pelaksanaannya menghadapi banyak kendala terutama dalam hal sarana dan prasarana terutama bagi sekolah-sekolah swasta di pedesaan Lombok Barat. Salah satunya adalah SMA IT Al Kamal NW Narmada yang terletak di Desa Golong Kecamatan Narmada, Lombok Barat. Sekolah yang berdiri tahun 2008 ini belum memiliki fasilitas ruang dan alat laboratorium. Hal ini sangat menyulitkan siswa untuk dapat memahami konsep-konsep IPA secara lebih mendalam tanpa disertai praktikum. Sehingga perlu dilakukan inovasi dengan memanfaatkan barang-barang bekas yang mudah diperoleh untuk dijadikan alat peraga sederhana. Salah satu inovasi yang telah dilakukan adalah perancangan dan pembuatan sendiri alat praktikum destilasi sederhana, untuk membantu siswa memahami konsep destilasi serta penerapannya dalam industri. Diharapkan pengabdian ini akan meningkatkan kreatifitas dan minat para siswa/siswi SMA IT Al Kamal untuk mengembangkan penggunaan alat destilasi sederhana tersebut dalam bidang praktis seperti pertanian sehingga dapat juga menigkatkan jiwa kewirausahaan siswa.Kata kunci : alat destilasi sederhana, praktikum, wirausaha Abstract: Improvement of human resources faces many challenges, especially in terms of facilities and infrastructure, especially for private schools in rural, West Lombok. One of the high schools that face the same problem is the High School IT Al Kamal NW Narmada located in the village ofGolong District of Narmada, Lombok Barat. School was established in 2008 but have no adequate classroom facilities and laboratory equipment. It is very difficult for students to understand science concepts in more depth without laboratory work activity. Therefore it needs innovation for simple laboratory work activity by utilizing second-hand goods that readilyavailable. The simple innovation that has been introduced is to design and manufacture simple distillation apparatus in order to help students understand the concept of distillation and its application in the industry. This approach is expected to increase creativity and interest of the student especially from SMA IT Al Kamal to develop simple destilation apparatus for practical purposes (e.g in agriculture) so that it is espected that student has entrepreneurs skills.

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The corrosion inhibition efficiency of copper was tested by the weight loss method in 1 M H2SO4 medium in the presence of pinostrobin as inhibitor. It shows that the addition of pinostrobin inhibitor reduce the corrosion rate. The nature of thermodynamic of pinostrobin adsorption on copper surfaces follows the Freundlich isotherm. The process of inhibition is endothermic, spontaneous and physisorption. It is proved by the Ea, ΔH and ΔS and ΔG values in which the thermodynamic studies show that the values of Ea < 80 kJ.mol-1, ∆H positive, ∆S positive, and ΔG < -20 kJ.mol-1.

Eugenol is a compound with a variety of reactive functional groups such as allyl