Comparative study of stirred and fluidized tank reactor for hydroxyl-kojic acid derivatives synthesis and their biological activities

2017 ◽  
Vol 43 (3) ◽  
pp. 205-219 ◽  
Author(s):  
Ahmad Firdaus B. Lajis ◽  
Muhajir Hamid ◽  
Syahida Ahmad ◽  
Arbakariya B. Ariff

AbstractBackground:Study on the synthesis of kojic acid derivatives (KADs) in solvent-free system using scalable reactors and their biological activities is still lacking.Methods:In this study, two types of KADs, were synthesized using saturated-fatty acid [lauric acid (LA)] and unsaturated-fatty acid [oleic acid (OA)] in stirred tank reactor (STR) and fluidized tank reactor (FTR). The yield and biological activities of the synthesized KADs were evaluated and compared.Results:The highest yield of KADs (42.95%) was obtained in the synthesis using OA, with molar ratio of 1:1, enzyme loading of 5% (w/v), temperature of 70°C, using immobilized lipase N435 in STR. However, FTR may provide biocatalyst protection and reusability with reduced loss of KADs yield up to three cycles. In antioxidant assay, the hydroxyl-unsaturated-fatty acid of kojic acid (HUFA-KA) showed better activity as compared to hydroxyl-saturated-fatty acid of kojic acid (HSFA-KA) at concentrations ranging from 125 to 2000 μg/mL. In contrast, HSFA-KA showed better cytotoxicity effect against G361 melanoma cell as compared to HUFA-KA.Conclusion:The yield of KADs obtained in STR was higher than that obtained in FTR. HUFA-KA could be used as potential lipophilic antioxidant while HSFA-KA has the potential to be used to treat melanoma skin disorder.

2013 ◽  
Vol 724-725 ◽  
pp. 1154-1157 ◽  
Author(s):  
Sawittree Mulalee ◽  
Jiranan Chanprasert ◽  
Piboon Kerdpoksup ◽  
Netnapa Sawangpanya Sawangpanya ◽  
Muenduen K.M. Phisalaphong

Biodiesel has been receiving significant attention as a renewable and nonpolluting fuel. In this study, oleic acid and bioalcohols (ethanol and butanol) were used as substrates for biodiesel production. The reactions were performed in a solvent-free system using immobilized lipase (Novozym 435) as biocatalyst in a batch esterification process. The optimal conditions were 45°C, oleic acid to alcohol molar ratio of 1:2, Novozym 435 loading at 5% based on oleic acid weight and 250 rpm, in which the free fatty acid (FFA) conversion at 91.0% was obtained after 12 hours of the reaction.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Sunil Kumar Narwal ◽  
Nitin Kumar Saun ◽  
Priyanka Dogra ◽  
Ghanshyam Chauhan ◽  
Reena Gupta

A novel thermotolerant lipase fromBacillus aeriuswas immobilized on inexpensive silica gel matrix. The immobilized lipase was used for the synthesis of biodiesel using castor oil as a substrate in a solvent free system at 55°C under shaking in a chemical reactor. Several crucial parameters affecting biodiesel yield such as incubation time, temperature, substrate molar ratio, and amount of lipase were optimized. Under the optimized conditions, the highest biodiesel yield was up to 78.13%. The characterization of synthesized biodiesel was done through FTIR spectroscopy,1H NMR spectra, and gas chromatography.


2008 ◽  
Vol 73 (2) ◽  
pp. 147-156 ◽  
Author(s):  
Nevena Ognjanovic ◽  
Dejan Bezbradica ◽  
Zorica Knezevic

Response surface methodology was used for the evaluation of the effects of various factors on the synthesis of biodiesel catalyzed with immobilized lipase from Rhizomucor miehei in a solvent-free system. The production of biodiesel was optimized and model response equations were obtained, enabling the prediction of biodiesel production from the values of the four main factors. It would seem that the reaction temperature and the amount of water predominantly determined the conversion process while the methanol/oil molar ratio had no significant influence on the reaction rate. The temperature and amount of water showed negative interactive effects on the observed reaction rate per amount of enzyme. However, there were no significant interactions among the other variables according to the test of statistical significance. The highest yield of 10.15 mol kg-1 enzyme was observed at 45?C with a 6:1 methanol to oil molar ratio and with no added water in the system.


2019 ◽  
Vol 8 (1) ◽  
pp. 30-37 ◽  
Author(s):  
Girish S. Nhivekar ◽  
Virendra K. Rathod

Abstract Polyethylene glycol stearate is widely used in pharmaceuticals and cosmetic industries. The current work describes the synthesis and optimization of polyethylene glycol stearate by esterification of polyethylene glycol 600 and stearic acid using Fermase CALBex 10000, a commercial immobilized lipase B in a solvent-free system. The impact of various parameters that include temperature, reaction time, biocatalyst loading, agitation, acid to alcohol molar ratio, and amount of molecular sieves was optimized to achieve maximum conversion. The highest conversion of 86.98% was obtained in 6 h under the following optimized conditions: temperature 70°C, biocatalyst loading 0.5%, acid to alcohol molar ratio 1:4, speed of agitation 300 rpm, and molecular sieves 5% (w/w). The final condensate product was analyzed through Fourier transform infrared spectroscopy to confirm the functional group and also by 1H nuclear magnetic resonance spectroscopy. The immobilized catalyst can be reused up to four cycles, exhibiting more than 60% of its initial activity.


Fuel ◽  
2010 ◽  
Vol 89 (12) ◽  
pp. 3960-3965 ◽  
Author(s):  
Liping Zhang ◽  
Shuzhen Sun ◽  
Zhong Xin ◽  
Boyang Sheng ◽  
Qun Liu

2020 ◽  
Author(s):  
Federico Acciaretti ◽  
Andrea Pasquale

AbstractPlasticisers are commonly incorporated in plastic materials in order to improve their physico-chemicals properties. In particular, Poly-(vinyl chloride) (PVC) is a polymer which has excellent plasticiser compatibility characteristics. The demand for plasticized-PVC is steadily increasing and its synthesis need to be more sustainable, considering the interest in developing a circular economy in the next years. In order to achieve these goals, a bio-based process to synthesize di(2-ethylhexyl) adipate (DEHA), a widely used plasticiser, could be an interesting approach. The most important starting material for the process is adipic acid, but its synthesis from petrochemical sources is not sustainable. An alternative is using waste materials as substrates for fermentation in a totally green process. Among many strategies, the reverse adipate degradation pathway (RADP) in E. coli seems to be the most interesting one, considering the highest titer of 68 g/L and the yield of 93.1%. The next step is the enzyme-catalysed esterification of adipic acid and 2-ethylhexanol to produce DEHA, using an immobilized lipase from Candida antarctica. Applying a solvent-free system under vacuum condition is convenient as it guarantees a conversion to DEHA of 100 mol%.


2021 ◽  
Vol 24 (1) ◽  
pp. 122-130
Author(s):  
M Lamudin Noor ◽  
Andarini Diharmi ◽  
Rahman Karnila

Minyak ikan patin mengandung kadar asam lemak omega-9, tetapi rendah asam lemak omega 3 Minyak hati ikan hiu memiliki kandungan asam lemak omega 3 relatif tinggi. Penelitian ini bertujuan untuk menentukan karakteristik dan sifat kimia minyak ikan patin dan profil asam lemak kombinasi minyak ikan patin dengan hati kan hiu. Metode penelitian eksperimen dengan melakukan ekstraksi lemak perut ikan patin secara dry rendering dihasilkan minyak kasar dan dimurnikan. Minyak ikan patin murni dilakukan pencampuran dengan minyak hati ikan hiu. dengan perbandingan 1:1, 2:1 dan 2:1. Parameter analisis terdiri atas karakteristik kimia (bilangan asam lemak bebas (ALB),bilangan  asam, peroksida, iod,  p-anisidin, penyabunan, total oksida/totox), dan profil asam lemak. Hasil penelitian menunjukkan bahwa kombinasi  minyak patin dan hati ikan hiu dihasilkan karakteristik kimia terdiri atas asam lemak bebas sebesar 1,59-2,19%, bilangan asam 2,86-3,00 mg KOH/g, peroksida 15,50-18,32 meq/kg, iod 63,46-84,42 gI2/100g), p-anisidin 21,53-24,16, penyabunan 142,21-162,28 mg KOH/g dan TOTOX 53,33-69,43. Hasil analisis komposisi asam lemak jenuh (saturated fatty acid/SAFA) dihasilkan  asam palmitat tertinggi,  asam lemak tak jenuh tunggal  (mono unsaturated fatty acid/MUFA)  asam oleat,  dan asam lemak tak jenuh ganda (polyunsaturated fatty acid/PUFA)  asam linoleat. Hasil analisis karakteristik kimia kombinasi  minyak ikan patin dan hati ikan hiu sesuai dengan standar IFOMA. Kombinasi minyak hati ikan hiu dan ikan patin dengan perbandingan (2:1) dihasilkan kandungan omega 3 dan omega 6 sebesar 2,59 % dan 29,75%.


Catalysts ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 338 ◽  
Author(s):  
Shang-Ming Huang ◽  
Ping-Yu Wu ◽  
Jiann-Hwa Chen ◽  
Chia-Hung Kuo ◽  
Chwen-Jen Shieh

Ferulic acid esters have been suggested as a group of natural chemicals that have the function of sunscreen. The study aimed to utilize an environmentally-friendly enzymatic method through the esterification of ferulic acid with octanol, producing octyl ferulate. The Box-Behnken experimental design for response surface methodology (RSM) was performed to determine the synthesis effects of variables, including enzyme amount (1000–2000 propyl laurate units (PLU)), reaction temperature (70–90 °C), and stir speed (50–150 rpm) on the molar conversion of octyl ferulate. According to the joint test, both the enzyme amount and reaction temperature had great impacts on the molar conversion. An RSM-developed second-order polynomial equation further showed a data-fitting ability. Using ridge max analysis, the optimal parameters of the biocatalyzed reaction were: 72 h reaction time, 92.2 °C reaction temperature, 1831 PLU enzyme amount, and 92.4 rpm stir speed, respectively. Finally, the molar conversion of octyl ferulate under optimum conditions was verified to be 93.2 ± 1.5%. In conclusion, it has been suggested that a high yield of octyl ferulate should be synthesized under elevated temperature conditions with a commercial immobilized lipase. Our findings could broaden the utilization of the lipase and provide a biocatalytic approach, instead of the chemical method, for ferulic acid ester synthesis.


Sign in / Sign up

Export Citation Format

Share Document