Successive Transesterification Research Articles

Harnessing a thermo-active and alkaline lipase from novel strain of Brevibacillus borstelensis gp-1, for application in biodiesel synthesis

A novel thermo-active and alkaliphilic strain of Gp-1, isolated from hot water springs of Ganeshpuri, Maharashtra, India, identified as Brevibacillus borstelensis based on 16SrDNA characterization, with accession no. MT292327, at NCBI database. Statistical optimization of lipase production was done using Plackett-Burman algorithm and response surface methodology. Fermentative production of Gp-1 lipase was followed by partial purification, with 24.10 fold purification. Gp-1 lipase has molecular mass of 31 kDa, as determined by SDS-PAGE. Gp-1 lipase exhibited maximal specific activity at pH 10 and 55 °C, with stability up to 70 °C. Kinetic parameters analysis revealed Gp-1 lipase has Km and Vmax values of 1.544 mM and 31.25 μM/mg. min, and specificity constant of 281.13 sec-1, with pNP caprylate as the base suited substrate. Gp-1 lipase was found to be retain more than 90% activity in presence of various organic solvents, and various commercial detergent formulations. The Gp-1 lipase was also tested for transesterification reactions, which revealed successful transesterification of coconut oil, olive oil and waste cooking oil, and conversion in esters. Hence, Gp-1 lipase stands out as a prospective candidate in biodiesel synthesis, a green energy alternative.

Advancing biorefinery technologies through transesterification and hydrothermal liquefaction for biodiesel and bioproducts production

BackgroundThe multicriteria assessment of advancing biorefinery to produce biodiesel (fatty acid methyl ester), glycerol, and torrefied pellets is a strategic approach towards sustainable development. MethodsA successive transesterification process was applied to separate lipids with alcohol, with a 1:7 mass-to-mass ratio in the presence of a heterogeneous catalyst of chitosan/polyvinyl alcohol-sodium hydroxide (CS/PVA-NaOH), to produce biodiesel and glycerol. Moreover, the remaining biomass is extracted to produce torrefied pellets by applying torrefaction through hydrothermal liquefication at 200–300 ℃ temperature. The biorefinery system using 613 kg organic fraction of municipal solid waste (OFMSW) produced 127.3 L of biodiesel, 14.5 kg of glycerol, and 387.5 kg of torrefied pellets. The whole systematic approach revealed two distinct areas with required characterized equipment such as dryer (A = 721.28m2), suspended in tank (V = 751.56m3), reactor (V = 721.56m3), cyclone (A = 743.48 m2), grinder (Q = 1352.31 m3/h), compactor (Q = 1367.31 m3/h), correspondingly. A gate-to-gate life cycle assessment (LCA) was performed for life cycle impact assessment (LCIA) through GaBi by using the ReCiPe 2016 Mid-point (H) and Endpoint (H) approach with a functional unit of 1000 kg municipal solid waste (MSW). Significant findingsThe economic assessment reveals the economic feasibility of the biorefinery project. The annual revenue determined the profitability index, which is $ 1.59 million annually, with a payback period of 1.8 years. The environmental analysis determined an eco-friendly production unit which can save 13.6% of carbon emissions by alternate use of photovoltaic energy. Conclusively, the calculated values and findings prove that biorefinery development using OFMSW is scientifically a win-win situation and notably assists in achieving circular bioeconomy and sustainable development goals (SDGs).

A Green Nanocatalyst for Fatty Acid Methyl Ester Conversion from Waste Cooking Oil

This study used a novel combination of cellulose nanocrystals (CNCs) and calcium oxide (CaO) nanocomposite (CaO/CNCs) for the production of biodiesel from waste cooking oil. The filter paper was used as a raw cellulose source to produce the CNCs from the acid hydrolysis of cellulose with sulfuric acid. The as-synthesized CaO/CNC nanocomposite is recyclable and environmentally friendly and was characterized using Fourier transform infrared spectroscopy, energy dispersive X-ray, scanning electron microscopy, and X-ray diffraction. The optimum process parameters investigated are a 20:1 methanol-to-oil molar ratio, 3-weight percent catalyst concentration, 60 °C temperature, and 90 min of reaction time. Under the optimum conditions, a biodiesel yield of 84% was obtained. The CaO/CNC nanocomposite achieved five times reusability, indicating its effectiveness and reusability in the transesterification reaction. The synthesized biodiesel chemical composition was examined using FTIR, GCMS, 1H-NMR, and 13C-NMR, and its properties, including specific gravity, color, flash point, cloud point, pour point, viscosity, sulfur content, sediments, water content, total acid number, cetane number, and corrosion test, were ascertained using ASTM standard practices. The outcomes were determined to fulfill global biodiesel standards (ASTM 951, 6751). Five successive transesterification processes were used to test the regeneration of the catalyst; the first three showed no distinct change, while the fifth cycle showed a reduction of up to 79%. The innovative composite CaO/CNC and used cooking oil are stable, affordable, and extremely successful for long-term biodiesel generation.

Polyethyleneimine-immobilized CoCl2 nanoparticles: Synthesis, characterization, application as a new efficient and reusable nanocomposite catalyst for one-step transesterification reaction

Polyethyleneimine-supported cobalt (II) chloride as a novel polymeric nanocomposite acidic catalyst for the one-stage transesterification reaction of ethyl acetate with various alcohols is reported. The catalyst was characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, dynamic light scattering technique, and thermal gravimetric analysis. Furthermore, inductively coupled plasma and atomic absorption spectroscopy were used to determine the quantity of Cobalt nanoparticles in the catalyst. By adding the catalyst (0.10 g, 0.20 mol%) and n-hexane/chloroform (5.0 cm3) as solvent under reflux conditions, the studies demonstrated successful transesterification reactions with excellent yields (80–98%) and short reaction times (0.50–1.30 h) using various substrates on the scale of 1.0 mmol. Seven consecutive reactions could be performed on the catalyst without significantly decreasing its activity. The most noteworthy aspects of this process are its low cost, safety, and environmental friendliness due to the catalyst’s non-toxicity, straightforward operation, and effective outcomes.

Development of bio lubricant from castor oil via chemical softening: An ease towards sustainable substitute

In the 21st century, Environment sustainability is considered to be the superficial,coherent vision in the development of a societal goal. At the moment, the prices of crude oil have been skyrocketing which results into the depletion of petroleum reservoirs contributing to environmental pollution cum hazards. This has inspired researchers globally in the development of non-toxic, renewable, and sustainable. ecologically sound alternative i.e., Bio-lubricant which will aim to replace conventional petroleum-based lubricants towards a green and clean society deliberately. The proposed work introduces the design and development of biodegradable bio-lubricant from commercially available, non-edible castor oil via chemical softening by the virtue of two successive transesterification stages. The presented study, explores the chemical modification process of vegetable oil to intensify the yield, grade, and physicochemical vis-a-vis tribological properties of the produced lubricant. The proposed method of production of castor oil-based bio-lubricant via chemical softening is made to achieve a high yield i.e., exceeding 97.4 % with a kinetic investigation for optimized parameters including catalyst concentration, alcohol/oil ratio, temperature, additives calibrated to be 1% w/w NaOH, 6:1, 65 °C and 15% SLS (Sodium lauryl sulfate) respectively for the maximum conversion with minimum costs associated with the production of ecologically viable castor oil-based bio-lubricant. The peaks observed at 1730 cm−1 and 3025 cm−1 are associated with the stretching vibration of the carbonyl group (C = O) in the ester bond and the stretching of the C–H bond vibration in the fatty acid chains, respectively. This has been confirmed through Fourier-transform infrared spectroscopy (FTIR) and evaluated through ASTM analyses.

One-Pot Production of Sugarcane Bagasse Polysaccharide-Based Thermoplastics via Pretreatment and Successive Transesterification Using 1-Ethyl-3-methylimidazolium Acetate

One-Pot Production of Sugarcane Bagasse Polysaccharide-Based Thermoplastics via Pretreatment and Successive Transesterification Using 1-Ethyl-3-methylimidazolium Acetate

Transformation of waste seed biomass of Cordia myxa into valuable bioenergy through membrane bioreactor using green nanoparticles of indium oxide

Depletion of non-renewable fuel has obliged researchers to seek out sustainable and environmentally friendly alternatives. Membranes have proven to be an effective technique in biofuel production for reaction, purification, and separation, with the ability to use both porous and non-porous membranes. It is demonstrated that a membrane-based sustainable and green production can result in a high degree of process intensification, whereas the recovery and repurposing of catalysts and alcohol are anticipated to increase the process economics. Therefore, in this study sustainable biodiesel was synthesized from inedible seed oil (37 wt%) of Cordia myxa using a membrane reactor. Transesterification was catalyzed by heterogenous nano-catalyst of indium oxide prepared with leaf extract of Boerhavia diffusa. Highest biodiesel yield of 95 wt% was achieved at methanol to oil molar ratio of 7:1, catalyst load 0.8 wt%, temperature 82.5 °C and time 180 min In2O3 nanoparticles exhibited reusability up to five successive transesterification rounds. The production of methyl esters was confirmed using Fourier-transform infrared spectroscopy and Nuclear Magnetic Resonance. The predominant fatty acid methyl ester detected in the biodiesel was 5, 8-octadecenoic acid. Biodiesel fuel qualities were determined to be comparable to worldwide ASTM D-6571 and EN-14214 standards. Finally, it was concluded that membrane technology can result in a highly intensified reaction process while efficient recovery of both nano catalysts and methanol increases the economics of transesterification and lead to sustainable production.

Effects of Water Removal from Palm Oil Reactant by Electrolysis on the Fuel Properties of Biodiesel

Biodiesel, which is composed of mono-alkyl esters of long carbon-chained fatty acids, is used as an alternative fuel to petro-diesel. The water content of the reactant mixture of feedstock oil influences the extent of transesterification and thus the fuel characteristics. Lower water content in feedstock oil is generally suggested for successful transesterification. This experimental study removed water from the reactant mixture of feedstock palm oil and methanol during transesterification using various systems composed of either electrodes or molecular sieves with rotary vibration. The effect of input electrical energy, number of electrodes, vibration modes, and operating time on the amount of water removed from the reactant mixture and the fuel properties of the final biodiesel product were analyzed and compared with those achieved using molecular sieves. The results show that the biodiesel—after water was removed during transesterification—appeared to have increased kinematic viscosity, cetane index, distillation temperature, and acid value, while the heating value, flash point, ignition point, and water content decreased with an increase in the input electrical energy of the electrodes responsible for electrolyzing water away. Electrolysis by the double-pair electrodes was more effective at reducing acid value and water content than that performed by the single-pair electrodes under the same input electrical energy. The biodiesel was found to have the lowest water content (0.0304 wt.%) and the highest water-removal rate (0.011 wt.%) when water was removed during transesterification by the double-pair electrodes with an input electrical energy of 9 J/(g palm oil). The water-removal rate of the rotary-vibrating molecular sieves was 11.24 times that of the single-pair electrodes. The biodiesel was found to have increased kinematic viscosity with higher input electrical energy, reaching 5.15 mm2/s when the double-pair electrodes with an input electrical energy of 11 J/(g palm oil) were used. Longer carbon-chained fatty acids, ranging from C20 to C24, amounted to 0.74 wt.% of the biodiesel produced using the double-pair electrodes, which was greater than that seen for the single-pair electrodes. However, the molecular sieve method consumed more energy than the double-pair electrodes did to remove the same amount of water from the palm oil reactant mixture via transesterification.

Influence of Biodegradable Refrigeration Oil in Household Refrigerator Compressor: An Experimental and Tribological Investigation

The present investigation is aimed at finding the suitability of using vegetable oil-based polyol ester as biodegradable refrigeration oil. Rapeseed oil-based pentaerythritol ester was synthesized via successive trans-esterification route. The formulation was blended with synthetic refrigeration oil (POE68) in the fractions of 25%, 50% and 75% by volume. The tribological investigation involving various refrigeration oils was done using the four-ball tribometer. This study further quantifies the influence of biodegradable refrigeration oils on the performance of domestic refrigerator compressor using vapour compression refrigeration test setup. The process of tribological analysis brought to light the comparable anti-friction and excellent wear reduction behaviour with the blended refrigeration oil sample (BIO50—i.e., 50% by vol. of pentaerythritol ester of rapeseed oil and 50% by vol. of POE68). It was noticed that the BIO50 had considerable rise in coefficient of performance (COP) of about 41.7% and prime impact on the performance of refrigeration compressor. The outcome of the experimental study is supportive in finding vegetable oil-based refrigeration oil to substitute partially the synthetic grade for the domestic refrigerator compressor.

Animal bone affluence in environmental reclamation: Biodiesel production, petro‐diesel biodesulfurization and wastewater photo‐treatment

AbstractThis study provides a new emphasis for research on the valorization of biowastes into nanocatalyst and biorefineries to be integrated with petroleum bioupgrading and polluted water treatment. The response surface optimized batch transesterification of waste‐frying oil using methanol and sustainable animal bone valorized fluorapatite nanocatalyst (FAP) yielded approximately 97% biodiesel via a pseudo‐second‐order reaction with an efficient rate of 0.48 (mol L−1)−1min−1 and activation energy of 13.11 kJ mol−1. In a pioneering step, by‐products of the starch industry and the biodiesel transesterification process; corn‐steep liquor (CSL 0.2 g L−1) and bioglycerol (6.24 g L−1) as nitrogen and carbon sources, increased the dibenzothiophene biodesulfurization (BDS) efficiency of a novel biodesulfurizing Rhodococcus jialingiae strain HN3 (NCBI Gene Bank Accession No. MN173539) sixfold. Further, upon the application of such bioproducts in a batch BDS process (1/3 petro‐diesel/water) of 96 h; HN3 desulfurized 82.26% of 0.62 wt.% sulfur without affecting the petro‐diesel calorific value. In an attempt to reach zero waste, an auxiliary pioneering step was performed, where the spent waste FAP, after being efficiently used for four successive transesterification cycles, was applied to photo‐remediate 4‐nitrophenol polluted water under UV‐irradiation. Advantageously, the fresh and spent waste FAP recorded the same photodegradation capabilities. Where they obeyed the Langmuir–Hinshelwood kinetic model (R2 ≥ 0.966) recording the same rate constants (kapp 0.032 min−1) and were efficiently reused for four successive polluted‐water treatment cycles. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Synthesis, Characterization, and Evaluation of Solution Properties of Sesame Fatty Methyl Ester Sulfonate Surfactant.

The search for alternative, biodegradable, and sustainable raw materials to replace finite petrochemicals is an area of great interest. Triglycerides obtained from oilseed crops are such potential raw materials. In this study, sesame oil was trans-esterified to sesame fatty methyl esters (SEFAMEs) that were used as precursors in the synthesis of sesame fatty methyl esters sulfonate (SEFAMESO) surfactant. SEFAME and SEFAMESO surfactants were characterized by high-performance liquid chromatography–mass spectrometry (HPLC-MS), 1H NMR, and Fourier transform infrared (FTIR) spectra. HPLC-MS, 1H NMR, and FTIR spectra indicated successful trans-esterification and conversion of SEFAMEs to SEFAMESO. Solution properties of the SEFAMESO surfactant including hydrophilic–lipophilic balance (HLB) value, Krafft point, foam-ability, critical micelle concentration (CMC), counterion degree of binding and thermodynamic parameters such as ΔG°mic, ΔH°mic, ΔS°mic, ΔH°mic,* and TC were evaluated. The CMC values of SEFAMESO at 298.15 K were relatively lower than that of the sodium dodecyl sulfate (SDS) standard, and these values decreased to a minimum at 303.15 K and then increased with an increase in temperature. ΔG°mic values were negative indicating a spontaneous micellization process. ΔH°mic and ΔS°mic values revealed that micellization was entropy-driven at low temperatures and both entropy- and enthalpy-driven at high temperatures. ΔH°mic,* values were negative suggesting formation of stable micelles. The evaluated properties revealed the potential application of the synthesized surfactant as a cleansing agent.

Biodiesel production from Vitex doniana (black plum) seed oil via a two-step catalyzed transesterification

Increasing global energy demands have led to increased search for alternative sources of fuel. Due to its similarities with petroleum-based diesel, biodiesel arose as a potential replacement for diesel. In this study, biodiesel was produced from the seed oil of Vitex doniana (black plum) using a two-step catalyzed transesterification method. The biodiesel produced was also characterized. Physico-chemical analyses carried out on the produced biodiesel gave strong indication that it can serve as an alternative feedstock, having recorded a comparable flash point of 110 °C to American Society of Testing Materials and European Committee for Standardization standards; though kinematic viscosity measurements showed biodiesel products of relatively high viscosity which has the tendency to leave deposits on combustion. Spectroscopic analyses indicated successful transesterification with 95-98% biodiesel yield.
 
 Bull. Chem. Soc. Ethiop. 2020, 34(1), 75-82. 
 DOI: https://dx.doi.org/10.4314/bcse.v34i1.7

Acid-Base Catalyzed Transesterification of <i>Archontopheonix cunninghamiana</i> (Bangalow Palm) Seed Oil

Currently, majority of global energy is sourced from petrochemicals which comes with its attendant environmental challenges. Efforts are therefore focused on developing renewable sources for energy and biofuel is in the front burner for these alternatives. In this paper, we explored Archontopheonix cunninghamiana seed; an inedible and waste material, as an opportunity for alternative feedstock for biodiesel production. The oil extraction recorded a low yield which may not be economically viable; the transesterification of extracted oil gave 94.56% yield of biodiesel. Physicochemical analyses of the produced biodiesel showed viscosity of biodiesel to be 2.64 mm2 /s, which is within American Society for Testing Materials (ASTM) and EN590:1999 petrol diesel specifications. It also has a pour point value of 8 °C which is within acceptable range of European Committee for Standardization EN590:2008 for petrol diesel. The flashpoint was found to be 110 °C which make for easy handling and transportation and agrees with EN14214:2008 minimum value of 101 °C. Spectroscopic studies done on the extracted oil and the produced biodiesel showed successful transesterification of the oil and good biodiesel quality.Keywords: Archontopheonix cunninghamiana, bangalow palm, transesterification, biodiesel

Functional packaging films originating from hemicelluloses laurate by direct transesterification in ionic liquid

An alternative transesterification with vinyl laurate (VL) was applied for chemical modification of hemicelluloses (HC) to prepare functional packaging films. Successful transesterification was confirmed by FT-IR and NMR. Semitransparent laurated HC (LHs) films were prepared by solvent casting method. SEM indicated the ordered honeycomb-patterned surface and the dense cross section of LHs films. The LHs films exhibited excellent hydrophobicity with water contact angle about 120° and the enhanced mechanical properties with tensile strength and elongation at break as 33.94 ± 3.09 MPa and 22.41 ± 2.87%, respectively. The water vapor permeability (WVP) and oxygen permeability (OP) values of LHs films ranged from 1.59 ± 0.07 to 2.23 ± 0.11 (10−10·g/m·s·Pa) and 1.21 ± 0.04 to 4.24 ± 0.30 (cm3·μm/m2·d·kPa), respectively. Moreover, the films had acceptable antioxidant activity. In terms of these properties, the shelf life of green chilies could be largely extended to 15 days after packing with LHs films.

Gas Chromatography and Fourier Transform Infrared Analysis of Biodiesel from Used and Unused Palm Olein Oil

The need for quality control of biodiesel is important to ensure the development of a clean, trouble free and safe alternative fuel technology to fossil diesel. In this work, the gas chromatography analysis of the biodiesel produced from used frying oil was carried out using PerkinElmer Clarus 500 Gas Chromatograph (GC), fitted with a capillary split injector and Fourier Infrared Detector (FID). Also, the Fourier Transform Infrared Spectroscopy was used to determine and monitor the concentration of biodiesel produced from used and unused palm olein oil. The Fourier Transform Infrared (FTIR) analysis was carried out using the FTIR Spectroscopy (FTIR 1-S Shimadzu, Japan, Model 4100) and Microlab software as well as Attenuated Total Reflectance (ATR) sample interface system. 0.5 ml of samples of the unused palm olein oil and biodiesel were taken in at the interface at a resolution of 4 cm-1 within the region of 4000 cm-1 to 400 cm-1 . The GC-MS analysis did not indicate any soap-like material, indicating that the catalyst was able to handle transesterification reaction without transition to saponification reaction. The results of the interaction between the components of the fuel samples and the radiation as a function of wavelength indicates the functional groups and the type of vibration in the fuel samples. The results obtained indicate the presence of an intense band of C=O stretching of methyl ester and O-CH3 group. It also show concentration of the five main fatty acids that are present in most biodiesel; palmitic, stearic, oleic, linoleic, and linolenic acids indicating the successful transesterification of palm olein oil to biodiesel.

RSM and Crow Search Algorithm-Based Optimization of Ultrasonicated Transesterification Process Parameters on Synthesis of Polyol Ester-Based Biolubricant

This study investigated the optimization of ultrasound-aided transesterification process variables for the synthesis of polyol ester-based biolubricant. A response surface methodology based on Box–Behnken design coupled with crow search algorithm methodology was adopted to optimize the ultrasonicated transesterification process variables such as an ultrasonic pulse, amplitude, catalyst concentration, and reaction temperature in order to maximize the yield percentage of polyol ester. The formation of pentaerythritol ester was confirmed by Fourier transform infrared spectroscopy and gas chromatography. The significant properties of the new formulation were compared with synthetic grade compressor oil. Improved yield of 81.4% of pentaerythritol ester was accomplished with an ultrasonic pulse of 15 s, an ultrasonic amplitude of 60%, a catalyst concentration of 1.5 wt%, and the reaction temperature of 100 °C. This optimization study suggested that ultrasonicated successive transesterification process is an effective method in substituting conventional successive transesterification process for the synthesis of pentaerythritol ester-based biolubricant.

Experimental Investigation on Tribological Characteristics of Biodegradable Refrigeration Oil using Pin on Disc Tribometer

The present study addresses the issue of the tribological behaviour of cylinder liner and piston ring material of a hermetically sealed reciprocating compressor of Vapour Compression Refrigeration system under the influence of pentaerythritol ester based biodegradable refrigeration oil and compare with synthetic refrigeration oil (Polyol ester-ISO 68grade) using the pin on disc tribometer. Synthesis of pentaerythritol ester based biodegradable refrigeration oil for household domestic refrigeration compressors was carried out via successive transesterification of rapeseed oil. The biodegradable refrigeration oil was blended equally with synthetic refrigeration oil to formulate the best biolubricant. Further Energy Dispersive X-ray (EDX) technique was adopted for the chemical characterisation of the pin material surfaces. The wear behaviour of the tested pin materials were evaluated using scanning electron microscope. The results show that under same investigational conditions 50% blend of pentaerythritol ester biodegradable refrigeration oil (PBRO 50) with synthetic refrigeration oil demonstrated superior friction reduction performance and inferior wear reduction performance as compared to synthetic refrigeration oil.

ChemInform Abstract: Efficient Acylation and Transesterification Catalyzed by Dilithium Tetra‐tert‐butylzincate at Low Temperatures.

Abstract The acylation and transesterification of alcohols with vinyl acetate and carboxylic esters were investigated in the presence of a catalytic amount (1–10 mol %) of dilithium tetra- tert -butylzincate (TBZL) as a catalyst. The acylation proceeded quantitatively at 0 °C within 1 h. The transesterification occurred for a wide range of combinations of esters and alcohols at 0 to −40 °C. To the best of our knowledge, this is the first successful transesterification at such low temperatures. The time–conversion plots for the transesterification show that the reaction reached equilibrium within 5 min at 0 °C. The reaction proceeded quantitatively by addition of molecular sieves 4A. In addition, the transesterification proceeded even in the presence of H 2 O and amines.

Efficient acylation and transesterification catalyzed by dilithium tetra-tert-butylzincate at low temperatures

The acylation and transesterification of alcohols with vinyl acetate and carboxylic esters were investigated in the presence of a catalytic amount (1–10mol%) of dilithium tetra-tert-butylzincate (TBZL) as a catalyst. The acylation proceeded quantitatively at 0°C within 1h. The transesterification occurred for a wide range of combinations of esters and alcohols at 0 to −40°C. To the best of our knowledge, this is the first successful transesterification at such low temperatures. The time–conversion plots for the transesterification show that the reaction reached equilibrium within 5min at 0°C. The reaction proceeded quantitatively by addition of molecular sieves 4A. In addition, the transesterification proceeded even in the presence of H2O and amines.

Assessing the Enzyme Activity of Different Plant Extracts of Biomasses from Sub-Saharan Africa for Ethyl Biodiesel Production

This work focused on identifying plant biomasses as potential sources of lipases and their use as biocatalysts for ethyl biodiesel production. To that end, plant extracts prepared from dormant and germinated seeds of eight local (Burkina Faso) oil-bearing biomasses were tested as a biocatalyst for the hydrolysis and ethanol transesterification of sunflower oil. The optimum transesterification conditions with the most active extracts were then determined. The results of the hydrolysis and transesterification tests showed that the plant extracts from germinated Jatropha curcas (JG) and Moringa oleifera (MG) seeds contained lipases whose catalytic activity could be utilized without prior purification. The highest hydrolysis yield obtained was 88% using the JG extracts and 62% with the MG extracts after 24 h of reaction at 40 °C and at pH 7. For transesterification, the highest ethyl ester yield obtained was 94% with the JG extracts and 48% with the MG extracts after 144 h at 37 °C, following two successive transesterification reactions. Using the plant extracts in transesterification called for the stepwise addition of ethanol in a TAG:ethanol molar ratio of 1:0.3 at 6 h intervals to overcome the inhibiting effect of high ethanol concentrations on the catalytic activity of the plant extracts. In addition, a study on the influence of the reaction conditions showed that water had a negligible effect on transesterification yield when its content in the ethanol was lower than or equal to 5% (v/v) and that adding silica to the reaction medium led to an increase in transesterification yield.