Pear Seeds Research Articles

Pour Point Depression of Waxy Crude Oil Using Unmodified African Pear (Dacryodes edulis) Seed Oil

The pour point depression of a Nigeria waxy crude oil was investigated using unmodified African pear seed oil. Crude oil sample collected from a marginal field in Delta state was analyzed for its physiochemical parameters such as; specific gravity, API, kinematic viscosity, pour point and wax content. African pear seeds sourced from choba Port Harcourt were extracted of their oil content and the oil was analyzed for some oil quality parameters such as; free fatty acid (FFA), acid value, saponification value and iodine value. The results showed a crude oil of high wax content and extracted oil of low FFA and high saponification and iodine values. The waxy crude oil was dosed with the unmodified African pear seed oil of concentrations 0.1ml, 0.2ml and 0.3 ml. The result showed no reduction in the pour point of the crude oil at all concentrations. Therefore the African pear seed oil cannot be used as a pour point depressant in its pure state.

Optimization of torrefaction conditions on antioxidant activity of prickly pear seeds extract using response surface methodology and chemometric analysis

The prickly pear (Opuntia ficus-indica L., Cactaceae) seeds can be used as an alternative food product by the torrefaction process. Torrefaction is a pre-treatment process of biomass into solid fuel within a temperature range of 60-200°C. This study aimed to investigate the effect of torrefaction parameters on the antioxidant potential of prickly pear seeds, which is considered a food by-product, by using the Central Composite Design approach (CCD).The best torrefaction parameters found to have the optimal phytochemical contents were: 200°C and 50 min with 104.86±1.94 GAE/g extract for Total Phenolic Content (TPC), 200°C and 50 min with 81.23±0.90mg QE/g extract for Total Flavonoid Content (TFC), 200°C and 50 min with IC50=90.66±2.09 μg/ml for free radical scavenging activity (DPPH assay), 200°C and 50 min with IC50=124.9±4 μg/ml for radical cation total antioxidant capacity (ABTS assay). Our results demonstrated an increase of antioxidant activities with the increase of torrefaction parameters. Therefore, torrefaction has proven to be a value-added process to exploit prickly pear seed biomass and use it as a source of antioxidant food additives.

Insights into the adsorption mechanism of chlorpyrifos on activated carbon derived from prickly pear seeds waste: An experimental and DFT modeling study

The removal of chlorpyrifos (CPF) from water was achieved using activated carbon (AC) derived from prickly pear seeds (PPS) wastes, developed through chemical activation with phosphoric acid. Several physico-chemical characterization methods were employed. The determination of surface functions using the Boehm assay indicated that the processed AC predominantly possesses acidic functions. The results obtained from the Boehm assay were corroborated by the pH value of the point of zero charge (pHpzc), which was equal to 2.5. Specific area calculation by the BET (Brunauer Emmett Teller) method revealed a large specific area (SBET) of 1077.66 m2 g⁻1. Adsorption experiments of CPF on AC demonstrated that the pseudo-second order (PSO) model and the Freundlich model were the most suitable for kinetic and isothermal modeling, respectively. The maximum CPF adsorption capacity of the PPS AC was found to be approximately 35 mg g⁻1. A theoretical study employing the density functional theory (DFT) was conducted using the B3LYP/6-311G (d, p) method. The most reliable adsorption energy (Eads) and Gibbs free energy (ΔGads) values between CPF and the functional groups on the AC surface were calculated. Results indicated a strong interaction between the lactone group of AC and CPF (ΔGads = −7.15 kcal mol⁻1, ΔEads = −21.55 kcal mol⁻1) and the hydroxyl group (ΔGads = −6.61 kcal mol⁻1, ΔEads = −20.66 kcal mol⁻1). This study demonstrates that activated carbon possesses significant adsorption power, making it highly effective for depolluting water contaminated by pesticides. The application of the theoretical DFT method enhances the understanding of the adsorption phenomenon of CPF on AC.

The Effect of Boiled African Pear Seed Meal (Dacryodes edulis) on Growth Performance and Nutrient Digestibility of Weaner Rabbits

This study was carried out to determine the effects of boiled African pear seed meal on the performance and nutrient digestibility coefficient of Weaner rabbits. African pear seeds were washed, chopped into pieces, boiled for one hour, sundried and milled to produce a boiled African pear seed meal (BAPSM). Four diets were formulated and designated T1, T2, T3 and T4. T1 contained maize as the main energy source, and T2, T3, and T4 contained BAPSM at 5, 10 and 15% levels, respectively, replacing maize in the diets. Thirty-two Weaner rabbits aged between 6 – 7 weeks were used for the study. The rabbits were divided into four treatments of eight rabbits, and each treatment was allotted one of the diets in a completely randomized design (CRD). Each group was further divided into four replicates of two rabbits per replicate. The experiment lasted 12 weeks, and the data obtained were statistically analyzed. There were significant differences (p<0.05) in feed intake, final body weight, body weight gain and feed conversion ratio values. All investigated nutrient digestibility coefficient parameters were significantly affected (p<0.05) by the diets. It was concluded that boiled African pear seed meal could be included in Weaner rabbits' diets up to 15% level to enhance the performance and nutrient digestibility coefficient of the animals.

Algerian Prickly Pear Seed By-Products: Fatty Acids Composition, Antioxidant, Enzyme Inhibitory Activities towards Tyrosinase, Urease, α-Amylase, and Cholinesterase, along with the Ability to Protect from Thermal Protein Denaturation.

Prickly pear seed is a source of the most expensive oil in the world, which is rich in vitamins and polyunsaturated fatty acids. Its extraction generates a large quantity of press cake. These two by-products need to be valued. The current study aimed to assess the fatty acid composition of oil and the phytochemical composition of press cake. In addition, the antioxidant and the inhibition of thermal protein denaturation effects of both Algerian seed by-products were evaluated with their inhibitory action against the activities of urease, tyrosinase, α-amylase, and cholinesterase enzymes. The GC MS analysis result revealed the richness of our oil in linoleic (74%) and palmitic (13%) acids methyl esters, respectively. The chemical composition of press cake was characterized by a high value of dry matter (94.94 ± 0.05%), especially the carbohydrates (85.13 ± 0.94%). The results of antioxidant activity presented by IC50 and A0.5 ranged from 7.51 ± 0.03 to 88.10 ± 0.92 µg/mL. Furthermore, the IC50 values were 40.19 ± 1.21 and 61.18 ± 0.03 µg/mL in thermal protein denaturation assay, and ranging from 22.97 ± 0.72 to 385.99 ± 0.27 µg/mL for the inhibition of enzymatic activities. These results indicate that the studied oil can be one of the strongest oils for its impressive effects and also encourage us to reuse its press cake in feed livestock.

Protective Effects of Pear Extract on Skin from In Vitro and In Vivo UVA-Induced Damage.

The ancient Chinese medical book "Compendium of Materia Medica" records that pears can relieve symptoms of respiratory-related diseases. Previous research has shown that pear Pyrus Pyrifolia (Burm.f.) Nakai has antioxidant and anti-inflammatory properties. However, the anti-inflammatory, antioxidant, and anti-photoaging protective effects of Pyrus pyrifolia (Burm.f.) Nakai seed components have not been studied. Ultraviolet light (UV) causes skin inflammation, damages the skin barrier, and is an important cause of skin photoaging. Therefore, UV light with a wavelength of 365 nm was used to irradiate HaCaT and mice. Western blot, real-time quantitative polymerase chain reaction, and fluorescence imaging system were used to explore its anti-UVA mechanism. Dialysis membrane and nuclear magnetic resonance were used for the chemical constituent analysis of pear seed water extract (PSWE). We found that PSWE can significantly reduce UVA-induced skin cell death and mitogen-activated protein kinase phosphorylation and can inhibit the mRNA expression of UVA-induced cytokines (including IL-1β, IL-6, and TNF-α). In addition, PSWE can also reduce the generation of oxidative stress within skin cells. In vivo experimental studies found that PSWE pretreatment effectively reduced transepidermal water loss, inflammation, redness, and dryness in hairless mice. The molecular weight of the active part of pear water extract is approximately 384. Based on the above results, we first found that pear seeds can effectively inhibit oxidative stress and damage caused by UVA. It is a natural extract with antioxidant properties and anti-aging activity that protects skin cells and strengthens the skin barrier.

Purification of Pesticide-Contaminated Water Using Activated Carbon from Prickly Pear Seeds for Environmentally Friendly Reuse in a Circular Economy

This study proposes an innovative approach based on the concept of the circular economy. It involves treating deltamethrin-contaminated water using an activated carbon (AC) adsorption technique based on a highly adsorbent plant waste derived from prickly pear seeds (PPSs). Activated carbon was prepared from PPS via a simple pyrolysis process preceded by chemical impregnation with phosphoric acid. Thus, a whole range of physicochemical tests were carried out, including iodine number (QI2), methylene blue number (QMB), Bohem dosage, pHZC, Brunauer–Emmett–Teller analysis (BET), and scanning electron microscopy (SEM). The QI2 and QMB were, respectively, 963.5 (mg g−1) and 8.3 (mg g−1). The pHzc of activated carbon was 2.5, and the surface area BET was 1161.3 m2 g−1. Adsorption kinetics, isotherms, and thermodynamic studies of pesticides using activated carbon were established. The obtained results revealed that the adsorption of the pesticide by the activated carbon appeared to be chemisorption with an adsorption capacity of 1.13 mg g−1. The adsorption capacity increased with increasing temperature, which explains an endothermic adsorption interaction. These results are in agreement with the results found using the density functional theory (DFT) and showed that activated carbon has an interesting adsorption power, which makes it as efficient as commercial activated carbon and predisposes it to the depollution of aqueous solutions contaminated with pesticides.

Betanin dye extracted from ayrampo (Opuntia soehrensii) seeds to develop dye-sensitized solar cells.

Pigments extracted from ayrampo seeds of the Peruvian-native prickly pear (Opuntia soehrensii) were used in dye-sensitized solar cells with promising efficiencies. The performance of the solar cells was then improved via the addition of citric acid to stabilise the photosensitive dye, and an efficiency of 1.41% was achieved with current output remaining stable after 7 days. Upon testing in low-light conditions, the solar conversion efficiency of devices increased to 4%. This paper not only highlights the potential of natural sensitizers in DSSCs but also shows that simple extraction and gentle handling methods can contribute to the device performance.

Seed Germination and Growth Improvement for Early Maturing Pear Breeding.

Breeding early maturing cultivars is one of the most important objectives in pear breeding. Very early maturing pears provide an excellent parental material for crossing, but the immature embryo and low seed germination of their hybrid progenies often limit the selection and breeding of new early maturing pear cultivars. In this study, we choose a very early maturing pear cultivar 'Pearl Pear' as the study object and investigate the effects of cold stratification, the culture medium, and the seed coat on the germination and growth of early maturing pear seeds. Our results show that cold stratification (4 °C) treatment could significantly improve the germination rates of early maturing pear seeds. A total of 100 days of cold-temperature treatment in 4 °C and in vitro germination on White medium increased the germination rate to 84.54%. We also observed that seed coat removal improved the germination of early maturing pear seeds, with middle seed coat removal representing the optimal method, with a high germination rate and low contamination. The results of our study led to the establishment of an improved protocol for the germination of early maturing pear, which will greatly facilitate the breeding of new very early maturing pear cultivars.

Synergistic Effect, and Therapeutic Potential of Aqueous Prickly Pear Extract. In vivo Neuroleptic, Catatonic, and Hypoglycemic Activity

Background: Prickly pear "Opuntia ficus indica (L.) Mill. "otherwise known as the Indian fig tree, belongs to the family Cactaceae, and was known as a medicinal plant for its rich source of bioactive substances. Objective: The present work aims to promote prickly pear seeds for traditional therapy by phenolic profiling and pharmacological tests of aqueous extract. Method: An analytical quantification was performed by UV-Visible, and the identification of different bioactive compounds was done by HPLC-DAD. For pharmacological screening, an in vivo evaluation of the various tests, neuroleptic activity which consists of testing the recovery reflex; catatonic activity which is a test to detect catalepsy that can be characterized in animals by the administration of neuroleptic drugs; and for hypoglycemic activity a test was performed to assess glucose tolerance. Results: The administration of aqueous extract of the prickly pear seeds at a dose (400 mg/kg) allows a reduction in blood sugar with a maximum decrease of one and a half hours compared to the control group. Conclusion: This work makes it possible to postulate that the extract of prickly pear seeds is associated with a very interesting antihyperglycemic activity given its high content of phenolic compounds.

Physicochemical and Biological Characterization of Opuntia ficus-indica (L.) Mill. Seed Oil Collected from The Bordj Bou Arreridj Region, Algerian Highlands

Background: The prickly pear is well adapted to arid and semi-arid areas. It occupies an important part in the human diet and it is also used as fodder for livestock. It is an interesting plant due to the environmental conditions in which it grows and its resistance to extreme climatic conditions. The objectives of our study were to determine the biological effects of oil extracted from prickly pear seeds (Opuntia ficus-indica L. Mill.). Methods: The organoleptic characteristics and the physicochemical parameters of this oil were done. The antibacterial and antifungal effects of the oil were tested in vitro against certain numbers of pathogenic bacteria and fungi by the aromatogram method. The antioxydante activity and the GC-MS analysis were proceeded also in this study. Result: The results show that the bacterial strains Klebsiella pneumoniae and Enterococcus faecalis are the most sensitive to the acid oil of Opuntia ficus-indica (L.) Mill. with an inhibition diameter varying between 23 mm and 25 mm, respectively. On the other hand, prickly pear seed oil exhibits an antifungal effect mainly against Candida albicans (25 mm). The oil extracted was strongest active (IC50 = 0.55 mg/ml). This indicates that our oil exhibited high reducing activity. 18 components were found in prickly pear seeds oil after analysis by GC-MS, which are presented mainly by phthalic acid (45.04%), monounsaturated fatty acid (18.56%), polyunsaturated fatty acid (16.69%) and other components (19.71%). The oil of Opuntia ficus-indica (L.) Mill. seeds showed good biological activity grace to its richness in components.

Effect of Time and Temperature Storage on the Quality of unpasteurized Prickly Pear Juice Enriched with Hydro-soluble Opuntia ficus indica seeds Extract

This study aimed to evaluate the effect of incorporating hydrosoluble Opuntia ficus indica seeds extract in unpasteurized prickly pear juice and monitoring its stability. For this purpose, titratable acidity (TA), total soluble solids (TSS), browning index (BI), total phenolic compounds (TPC), total flavonoids (TF), antiradical activity (DPPH), ferric reducing antioxidant power (FRAP) and microbial analysis were monitored for both enriched and controlled juices during different time and temperature storage. Before storage, the enriched juice values were respectively 0.096±0.001%, 14.1±0.01%, 0.756±0.01, 133.3±3.4mgGAE/100ml, 5.58±0.07mgQE/100ml, 95.89±14.27mgGAE/100ml and 59.34±5.52mgGAE/100ml for TA, TSS, BI, TPC, TF, DPPH and FRAP; while 0.16±0%, 14.1 ±0.001%, 1.2±0.01, 88.39±4.2mgGAE/100ml, 3.98±1.003mgQE/100ml, 51.08±14.27 mgGAE/100ml and 50.33±5.16mgGAE/100ml for the control juice. The microbial analysis revealed the absence of microorganisms even the juices were unpasteurized. Moreover, the results revealed that the enrichment attenuated significantly the effect of storage; indeed, the use of the prickly pear seeds extract in combination with the juices can be a good alternative to enhance the shelf life of unpasteurized prickly pear juice, and improve their quality attributes as well as to minimize the unwanted changes in the nutritional and organoleptic properties.

Rapid and non-destructive prediction of adulterated chilli powder by employing pocket-sized NIR spectrometer and chemometrics

Chilli pepper is an economically important vegetable. This study aims to develop a non-destructive and rapid technique to detect the adulteration of chilli pepper powder with avocado pear seed and cola nut powder using handheld near-infrared spectroscopy (NIRS) in the range of 740–1070 nm. A clear cluster trend was achieved for chilli pepper and the adulterated samples by using principal component analysis (PCA). Classification models such as random forest (RF), support vector machine (SVM) and partial least square discriminant analysis (PLS-DA) together with various pre-processing methods were used to predict adulteration of chilli pepper samples. The optimum classification rate of 91.25 % was found for chilli pepper adulterated with pear seeds using MC-SVM while MC-PLSDA had 86.25 % for chilli pepper adulterated with cola nuts. The partial least square (PLS) regression model had a coefficient of determinant (R2) and root mean square error of prediction (RMSEP) values of 0.9853 and 5.06 % for pear seed and 0.9724 and 6.91 % for cola nut, respectively. The current study shows that NIR spectroscopy can classify and determine chilli pepper authenticity and adulteration levels of pear seed and cola nuts.

Comparative Study of the Solvent Extraction and Characterization of Oil from the Seeds of Avocado, Bush Pear and Cashew

Due to their many purposes and functions for mankind, oils from fruits and seeds are given a lot of importance today. As a result, there is a higher demand for cashew, avocado, and bush pear oils. The Soxhlet extractor and petroleum ether as the extracting solvent are used in this work to extract and characterize the oils from the seeds of Cashew, Avocado, and Bush pear. Physical and chemical studies of the extracted oil were performed alongside with the identification of any trace metals. The findings assessed the yield, color, relative density, refractive index, acid value, peroxide value, iodine value, and saponification value free fatty acid for Bush pear, Avocado pear, and Cashew seeds. The yield (%) of the oil produced from the various seeds of cashew, avocado, and bush pear oils is of specific significance. This finding reveals highest oil yield of 38.2% in Avocado pear oil, compared to 34.4% and 27.4% oil yield in Bush pear seed, and Cashew seed, respectively. In addition to being edible, Bush pear and Cashew oil's low acid value of 6.4 mg KOH/g and 7.7 mg KOH/g, respectively compared to Avocado oil's low acid value of 14.6 mg KOH/g avocado suggests that Bush pear and Cashew oils finds good applications in the paint industry. The study also showed that potassium had the highest concentration of any metal, with 45.8 mg/100g in avocado oil, compared 24.9 mg/100g and 1.68 mg/100g for Cashew seed oil and Bush pear, respectively. Zinc had the lowest concentration, with a value of 0.38 mg/100g observed in Cashew compared with 1.32 mg/100g and 2.06 mg/100g for Bush pear and Avocado, respectively. Hence, this reveals that Oils extracted from Cashew finds good applications in the production of hydraulic oil with exceptional lubrication properties. The FTIR study shows that functional groups including alkanes, alkenes, carbonyls, etc. are present in the seed oils of Bush pear, Avocado pear, and Cashew seeds.

Effect of Processing Temperature on the Yield of Oil from African Pear Seed

Effect of Processing Temperature on the Yield of Oil from African Pear Seed

Valorization of Prickly Pear Seed and Olive Husk Agricultural Wastes for Plastic Reinforcement: The Influence on the Mechanical and Thermal Properties

AbstractCurrently, food waste is a major concern for businesses, governments, and consumers. Fruit processing creates many of by‐products, from undesirables to fruit skins, seeds, and fleshy parts. These by‐products make up to 30% of the initial mass of processed fruit. This goal can be achieved by transforming fruit waste into reinforcement and integrating it into polymeric materials. In this work, olive husk flours (OHF) and prickly pear seed flours (PPSF) are used as reinforcements of poly (lactic acid) (PLA) matrix. Initially, the physico‐chemical, particle size, spectroscopy (FTIR), and thermal characterization of its fibers are studied and compared. Then, the composite materials studied are manufactured with a twin‐screw extruder having a fiber content of 10%, 20%, and 30% by weight; its properties have been studied and compared. The characterization of these two fibers shows that the quantity of cellulose is greater in the OHF and that the latter is more thermally stable. For the composite material, the PLA /OHF are the most responsive in thermal and mechanical behaviors since their degradation temperatures are closer to pure PLA and the tensile modulus is higher compared to the PLA/PPSF composites. The equilibrium water uptake value is higher for composites reinforced with OHF than systems with PPSF.

Determination of Bioactive Constituents and Mineral Contents of Avocado Pear Seed Oil

Edible oils of plant origins are fundamental components of human diet, and are essential for various industrial applications, such as in food, cosmetics, and pharmaceutical industries. Of increasing interest is the utilization of edible oils obtained from plant parts such as peels, seeds, rinds, leaves, flowers, and fruits, which are usually regarded as wastes. This study investigated the usability of edible oil extracted from avocado pear seed by assaying its bioactive constituents and mineral composition. The bioactive compounds in the oil were determined by Gas Chromatography Mass Spectroscopy (GC-MS), while the mineral content was assayed using Atomic Absorption Spectrometry (AAS). Results of the GC-MS analysis showed the presence of twenty nine compounds, with 18-Nonadecen-1-ol (13.20%) being the most predominant, and 3,7,7-Trimethyl-1,3,5-cycloheptatriene (0.24%) the least. Compounds such as 10-Undecyn-1-ol, 7-Hexadecenoic acid methyl ester, 14-methyl Pentadecanoic acid methyl ester, and Linolelaidic acid, methyl ester, identified in the avocado seed oil, have previously been reported to possess various biological activities, including antifungal, antioxidant, antimicrobial, hypocholesterolemic, antiandrogenic, hemolytic, anti-cancer and anti-inflammatory activities. Results of the mineral analysis showed that potassium (13.09 ± 0.22 mg/100 g) was the major element, while copper (0.06 ± 0.11 mg/ 100 g) was the least; cadmium and lead were not detected in the oil. The presence of pharmacologically important phytochemicals and essential minerals in avocado seed oil suggests its potential as a nutraceutical substance, with applications in food and drug preparations.

Adsorptive Evaluation of Activated Carbonized Avocado Pear Seed (Persea Americana) and Activated Carbonized orange peels (Citrus Sinensis) in Taking out Ni2+ ion in Contaminated Water

Grave and complicated pollution problems are posed by the existence of heavy metals trendy environment and this has been a focus of study all over the world. The Activated carbonized avocado pear seed (ACAPS) and activated carbonized orange peel (ACOP) were each soaked with potassium hydroxide (KOH) solution at a 1:1 ratio, for 48 hours, the outcome was washed, air-dried and separately oven dried at 105℃ for 6 hours and further heated in a muffle furnace (Carbolite AAF1100) at 2500C for 1 hour. The ACAPS and ACOP obtained were physicochemical characterized with scanning electron microscope (SEM) and Fourier-transform infrared (FT-IR) spectrophotometer. Ni2+ ions adsorption route on ACAPS as well as ACOP was considered by means of batch adsorption isotherm investigation. Adsorption forms was assessed by Freundlich, Langmuir, DRK, Tempkin as well as Flory-Huggin isotherm models. SEM picture, show that ACAPS posessed an enormous amount of different dimension pores and the ACOP had smaller amount of pores of smaller sizes. The R2 obtained varies from 0.92 to 1.00 and it points to the fact that all the isotherm simulation was competent to clarify the correlation in the data we got. ACAPS had more adsorption site, however, ACOP took up more Ni2+ ion per adsorption site on comparing Flory-Huggins isotherm model nFH values vis-a-vis Langmuir isotherm model qm values. In conclusion, ACAPS was a superior adsorbent when matched with ACOP, it was more than twice as effective for taking out Ni2+ ions from contaminated water owing to a blend of its enormous amount of different size openings and the functional groups on its surface, with a qm value of 18.18 and 8.70 mg/g in that order.

Physical and Chemical Treatment Effects on the Germination of Pear Seeds (Pyrus Communis L.)

Pear (Pyrus communis L.) is one of the important species of fruits that are widely cultivated in Syria. Seed propagation of the pear is an important way to obtain seedlings to be used as grafting assets, but the method of seed propagation is difficult due to the effect of dormancy factors in germination. The research was carried out during 2020 and 2021 to study the effects of stratification for three periods (30–60–90 days) using ascorbic acid at a concentration of 100 mg/L, and potassium nitrate at a concentration of 0.3% for breaking the dormancy of pear seeds. The results showed that the best averages were at stratification for 60 days and gave the percentage of germination as 31%, and the speed of germination at 1.28 seeds/day. Additionally, treatments of seed soaking with ascorbic acid or potassium nitrate (without stratification) contributed to improving the germination percentage to 7.67% and 3.67%, respectively, with significant differences compared with the control (1%). The best results were with stratification treatment for 60 days with ascorbic acid, where the percentage of germination reached 49.67% and the germination speed increased to 3.91 seeds/day, in addition to reducing the period required for germination to 21 days.

Yield optimization and fuel properties evaluation of the biodiesel derived from avocado pear waste

This work used a solvent extraction technique to obtain oil from avocado pear seeds and peels. Next, this extracted oil was pre-treated with methanol and H 2 SO 4 to decrease its free fatty acids below 1.0 wt%. A central composite design was employed to optimize biodiesel production via trans-esterification between the pre-treated extracted oil and methanol catalyzed by NaOH. The optimum biodiesel yield recorded was 91 wt% at a CH 3 OH/pre-treated extracted oil molar ratio of 8:1, catalyst dosage of 0.7 wt%, temperature of 65 °C, time of 60 min, and agitation speed of 400 rpm. The biodiesel was mixed with the fossil diesel at different mass ratios, and the diesel engine tests were carried out. Engine torque, speed, fuel consumption rate, thermal efficiency, brake power, and emissions were assessed. The results showed that the engine used less than 20 % biodiesel mixture to generate the same amount of useful work compared to fossil diesel. Overall, the 20 % biodiesel mixture exhibited the best engine performance among all biodiesel/fossil diesel ratios at a torque of 70 N m, speed of 1900 rpm, brake thermal efficiency of 0.631, brake specific fuel consumption of 0.129 kg/kW h, brake power of 13.9 kW and very low emissions. • Avocado pear waste was used as the feedstock for the production of biodiesel. • Response surface methodology was employed to evaluate and optimize the biodiesel production. • The adjusted model suggests a maximum biodiesel yield of 91 wt%. • The biodiesel yield predicted by the adjusted model is consistent with the experimental results. • B20 generates the same amount of useful work as that fossil diesel.