Epoxidized Jatropha curcas-based trimethylolpropane triester (ETMPJO) was prepared by the in-situ epoxidation reaction of trimethylolpropane ester (TMPJO) catalyzed by hydrogen peroxide (H2O2) in the presence of formic acid. The epoxidation process was optimized through the variable parameters such as hydrogen peroxide to tmpjo molar ratio, formic acid to TMPJO molar ratio, temperature and time of the epoxidation reaction. The results showed the epoxidation optimal condition was achieved at the molar ratio of TMPJO to H2O2 and formic acid of 1 : 2.0 and 1 : 2.5, temperature of 50 °C for 2 h, respectively. The resultant ETMPJO was characterized by using fourier transformation infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopies and gas chromatography analysis. The FTIR spectrum of ETMPJO showed the appearance of peaks at 825 and 908 cm–1 for the epoxy functional group. ¹H NMR spectrum showed a chemical shift at 2.88 ppm of the epoxide group protons. 13C NMR spectrum showed the chemical signal of carbon epoxide group at 54–57 ppm. At the optimal condition, the resultant ETMPJO obtained was at 91% yield with comparatively high relative conversion oxirane (RCO) of 87%. With high oxygen oxirane content (OOC) of 4.38, ETMPJO owns a good characteristic for an intermediate compound for possible further conversion to produce high-end products. Moreover, its physiochemical and lubrication characteristics indicated that ETMPJO is plausible to be used as biolubricants for industrial application.

Synthesis of new lubricants nowadays is increasing to improve the lubricity properties

Plant oil derived compounds have been used as the raw material for the synthesis of green biolubricant. Azelaic acid derived from oleic acid is one of the interesting compounds. The synthesis of azelate esters oil based synthetic green biolubricants was carried out. The esterification process of azelaic acid with variety type of alcohols was catalyzed by concentrated H2SO4. The yields percentages of azelate esters oil produced were varied depending their overall molecular structure. The azelate esters oil properties were evaluated for their suitability as a biolubricant. The results showed that the linear azelate esters oil showed high pour point values in a range of 15 to 5 ºC for di-decyl azelate, di-octyl azelate and di-hexyl azelate respectively. On the other hands, the branch azelate esters oil showed very low pour point of -70, -58 and -50 ºC for di-2-butyloctyl azelate, di-2-ethylhexanol azelate and di-2-ethylbutyl azelate, respectively. Moreover, the linear azelate esters oil gave high values of flash point, viscosity index and oxidative stability, and they were slightly affected by branching molecule structure. The tribological and rheological properties of high molecular azelate esters oil were also performed. Subsequently, most of them were classified as non-Newtonian fluids and having boundary lubrication properties with low friction coefficient. The branch azelate esters oil is plausible to be used as green biolubricants in many applications including automotive, marine engine oils, compressor oils, hydraulic fluids, gear oils and industrial biolubricants.

Monoepoxidation linoleic acid (MEOA) has advantages for industrial applications. MEOA was synthesized using immobilized Candida antarctica lipase (Novozym 435 ® ). At optimum conditions, higher yield (82.14 %) and medium oxirane oxygen content, OOC (4.91 %) of MEOA were predicted at 15 µL of H 2 O 2 , 120 mg of Novozym 435 ® and 7 hours of reaction time. Fourier Transform Infrared Spectroscopy (FTIR) spectra of the MEOA showed monoepoxide group at 820 cm -1 . 1 H NMR analysis confirmed the monoepoxide group at 2.92 -3.12 ppm while the monoepoxide signals of 13 C NMR appear at 54.59 -57.29 ppm. LC-MS analysis shows that of MEOA gives m/z at 296.22 as final product. MEOA exhibited good pour point (PP) of -41 ºC. Flash point (FP) of MEOA increased to 128 ºC comparing with 115 ºC of linoleic acid (LA). In a similar fashion, viscosity index (VI) for LA was 224 generally several hundred centistokes (cSt) more viscous than MEOA 130.8. MEOA was screened to measure their oxidative stability (OT) which was observed at 168 ºC. It is evident that increasing the hydrogen peroxide amount has a strong effect on the reaction kinetics; however, a large excess of hydrogen peroxide results in accumulation of peracid in the final product. Keywords: linoleic acid, Novozym 435® , self-epoxidation, renewable energy Abstrak Mono-pengepoksidaan asid linoleik (MEOA) mempunyai kelebihan untuk aplikasi industri. MEOA telah disintesis menggunakan Candida Antartika lipase (Novozym 435 ®) pegun. Pada keadaan yang optimum, peratus hasil MEOA sebanyak 82.1 % dengan kandungan oksigen oksirana (OOC) sebanyak 4.91 % diperolehi dengan menggunakan 15 µL H 2 O 2 , 120 mg Novozym 435 ® dan 7 jam tindak balas. Analisis 1 H NMR mengesahkan kumpulan terepoksida pada 2.92 -3.12 ppm manakala isyarat 13 C NMR menunjukkan bacaan pada 54.59 -57.29 ppm. Analisis LC-MS menunjukkan bahawa MEOA memberikan m/z 296.22 sebagai produk akhir. MEOA menunjukkan takat tuang yang baik pada suhu -41 ºC. Takat kilat MEOA meningkat pada suhu 128 ºC berbanding pada suhu 115ºC oleh asid linoleik (LA). Dalam keadaan yang sama, kebiasaanya VI untuk LA pada 224 beberapa ratus sentistok (cSt) lebih likat daripada MEOA 130.8. MEOA mempunyai kestabilan oksidatif pada suhu 168 ºC. MEOA berpotensi untuk dijadikan sebagai produk pertengahan dalam aplikasi tenaga keterbaharuan.

Objective: Present study aim for the purification of quantitative phytochemical compounds from roots of  Caralluma quadrangula belongs to the family Asclepiadaceae. This type of plants can be use as folk medicine  to take care of wide diversity of health  and diseases situation. Methods: Preliminary phytochemical analysis for different type of chemical compounds by using various  chromatographic techniques. The phytochemical characterizations were evaluated by nuclear magnetic resonance and mass spectrometry. Results: The quantitative phytochemical analysis of this species exhibited the presence four pure compounds,  hydroxyoplopan-4-one (4.5 mg), dihydroxyeudesm-4(15)-ene (5.0 mg), and quercetin- rhamnopyranosyl-D-glucopyranose (Rutin) (7.0 mg). Conclusion: From this study, it can be concluded that the species found four pure compounds from C. quadrangula. Peer Review History: Received 25 July 2020; Revised 10 August; Accepted 28 August, Available online 15 September 2020 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.5/10 Reviewer(s) detail: Name: Marwa  A. A. Fayed Affiliation: Faculty of Pharmacy, University of Sadat City, Egypt E-mail: maafayed@gmail.com   Name: Dr. Ali Gamal Ahmed Al-kaf Affiliation: Sana'a university, Yemen E-mail: alialkaf21@gmail.com   Name: Ahmad Najib Affiliation: Department of Pharmacognosy-Phytochemystry Universitas Muslim Indonesia-Indonesia E-mail: ahmad.najib@umi.ac.id   Comments of reviewer(s): Similar Articles: A STUDY OF PHYTOCHEMICAL CONSTITUENTS IN CARALLUMA QUADRANGULA PHARMACOGNOSTIC EVALUATION OF GOMPHRENA SERRATA ROOT

The current study aimed to evaluate the effect of long-chain and branch alcohol on lubricity of sebacic acid based ester. Since currently synthesis of a new lubricant to improve the lubricity properties and quality of lubricant is increasing, in this study, sebacic acid esters were synthesized by the conventional esterification method with some modification using sulfuric acid (SA) as catalyst. Twelve samples of sebacic acid esters with different chemical structures were synthesized including di-2-octyl sebacate, didecyl sebacate, di-2 ethylhexanol sebacate, di-2-ethylbutyl sebacate and dioleyl sebacate. These diesters were tested in terms of their suitability as lubricant. The results showed that the pour point, flash point and oxidation stability were affected by liner and branch of the alcohol used. Di-2-ethylbutyl sebacate (D2EBS) and di-2-ethylhexanol sebacate (D2EHS) showed very low pour point at -44°C and -60°C respectively, while the same carbon number of dihexyl sebacate (DHS) and dioctyl sebacate (DOS) recorded high pour point at 8°C and 15 °C respectively. These differences were due to the presence of the branching. DOS recorded the highest oxidative stability at 290°C. However, there was a slight negative effect of the branching on the flash point.

The physicochemical properties of Jatropha curcas (JC) seed oils are related to the plant varieties and affect the biodiesel quality when it is used as feedstock. This work investigates the physicochemical properties and feasibility of mutated JC seed oil for biodiesel feedstock. Three mutated JC seed oils, from JC-150, JC-226 and JC-300, were successfully evaluated. The oil contents were determined by using gravimetry methods. The AV, FFA, IV and PV were determined by using titrimetric methods. Types of fatty acids were analyzed by using a GC-FID. The triacylglycerol (TAG) and PE compositions were determined by using a HPLC-ELSD. The results show that the oil contents of JC-150, JC-226 and JC-300 seeds were 48.3%, 45.8%, and 51.7%, respectively. The PE contents in JC-150, JC-226 and JC-300 were lower (approximately 33.4%, 46.9% and 96.4%) compared to the control. The oleic and linoleic acids were two main components of all samples, with compositions in the range 41.82-42.45% and 36.68-37.45%, respectively. The compositions of polyunsaturated and monounsaturated TAG were obtained in the range 71.60-76.22% and 19.62-24.53%, respectively. These results show that the properties of mutated JC seed oils meet with the requirements for biodiesel production. JC-0 JC-150 JC-226 JC-300 Percentage of PE reduction (%) 0 20 40 60 80 100 FIGURE 3. The reduction of PE composition in the mutated jatropha oil and control.TABLE 1. Summary of physicochemical properties of the mutated JC seed oils and control. Parameter JC -0 JC-150 JC-226 JC-300 Seed moisture (%) 9.63 ± 0.06 8.30 ± 0.01 9.40 ± 0.01 8.80 ± 0.01 Oil content (%) 45.5 ± 0.1 48.3 ± 0.1 45.8 ± 0.1 51.7 ± 0.1 Oil moisture (%) 0.24 ± 0.01 0.20 ± 0.01 0.24 ± 0.01 0.23 ± 0.01 Acid value (mg KOH/g) 7.0 ± 0.2 2.5 ± 0.1 4.4 ± 0.2 2.7 ± 0.3 % FFA as oleic acid 3.5 ± 0.1 1.2 ± 0.1 2.2 ± 0.1 1.4 ± 0.1 Density (g/ml) 0.90 ± 0.01 0.89 ± 0.01 0.90 ± 0.01 0.89 ± 0.01 Viscosity (cSt) 23.9 ± 0.1 23.6 ± 0.1 24.9 ± 0.1 23.5 ± 0.1 Iodine (mg I2/g) 95.7 ± 0.1 94.2 ± 0.1 95.4 ± 0.1 94.2 ± 0.8 Saponification value (mg KOH/g) 213.7 ± 0.8 207.1 ± 3.2 208.5 ± 0.8 206.0 ±2.2 Un-saponification material (%) 0.

Thirteen samples of esters based on dodecanedioic acid with different chemical structures were synthesized. Among these were di-2-octyl dodecanedioate, didecyl dodecanedioate, di-2-ethylhexanol dodecanedioate, di-2-ethylbutyl dodecanedioate, dioctyl dodecanedioate, dihexyl dodecanedioate, and dioleyl dodecanedioate. Diesters were synthesized through the esterification of dodecanedioic acid with selected long-chain and branched alcohols with acid catalyst of H<sub>2</sub>SO<sub>4</sub>. These esters were tested in terms of their suitability for application as lubricants. The results showed that the lubricity properties, based on their pour point, flash point, and oxidation stability of the esters were significantly affected by the linear and branched alcohols used. An excellent pour point property of di-2-ethylbutyl dodecanedioate and di-2-ethylhexanol dodecanedioate at −55 °C and −50 °C was observed compared to their respective same linear carbon number esters of dihexyl dodecanedioate at 10 °C and dioctyl dodecanedioate at 20 °C. These are due to the presence of the branched group in their molecule vicinity structure. However, the esters flash points were insignificantly affected by the presence of branched structure. The selected esters could be used for biolubricants or engine oil.