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Cited by 6Insect Pest Control StrategiesPhytochemical compounds biological activitiesAgricultural and Biological Research

Optimized microwave-assisted azadirachtin extraction using response surface methodology

Open access
Martínez-Castro, Robinson, Flórez-Santiago, Jiress, Valle-Molinares, Roger, Cabrera-Barraza, Julián, Espitia-Almeida, Fabián·2024·Heliyon
DOI 10.1016/j.heliyon.2024.e31504PMC PMC11145488
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Abstract

The neem tree ( Azadirachta indica A. Juss) is grown mainly for shade, fuel, and numerous non-timber forest products using its leaves, fruit, and bark. It produces an essential oil that is used as a source for obtaining bioinsecticides, with a broad spectrum of action in agricultural production. Its bioinsecticidal activity is due to the presence of triterpenes, such as azadirachtin, a product in continued growth of the global biopesticide market. Optimal conditions for neem oil extraction using response surface methodology (RSM) and microwave-assisted extraction (MAE) methods have been defined. However, the extraction conditions for these methods tend to consume high volumes of organic solvent and long extraction times. The aim of the present study is to determine the optimal conditions for the extraction of azadirachtin from neem seeds in a hydroalcoholic medium using MAE and RSM with a Box-Behnken design (BBD). A BBD was applied to evaluate the effects of the factors, magnetron voltage (X 1 ), extraction time (X 2 ), and pH of the extraction medium (X 3 ), on the yield of the azadirachtin extraction process. The effect of each variable on the extraction yield was studied independently, considering the pure coefficients (linear and quadratic) on the three levels that were studied in the experiments. Moreover, the study experiments were conducted in triplicate, data were presented as mean and standard deviation, homogeneity of variances was estimated using Levene's test, and a two-way ANOVA with Tukey's post hoc analysis was performed to identify the experimental conditions that allowed us to find the highest extraction yield and to analyze whether the response surface model adequately described our data. The most significant effects of the model correspond to quadratic and interaction effects (p < 0.0001); the quadratic terms voltage (X 1 ), extraction time (X 2 ), and pH (X 3 ); and the interaction effects between voltage-pH (X 1 *X 3 ) and time-pH (X 2 *X 3 ), which had a significant influence on the model. Moreover, a canonical analysis was performed. The optimal conditions were as follows: 69.22 V, 6.89 min, and a pH value of 4.35, coinciding with the zones shown in the contour plots. Furthermore, the response obtained at the optimal conditions was 37.5 μg of azadirachtin per gram of pretreated seed.

Verified 2026-10-26 · 1 reference not checked yet

AI snapshot

Written from the paper’s full text.

TL;DR

This study optimized microwave-assisted extraction of azadirachtin from neem seeds in a hydroethanolic medium using response surface methodology with a Box-Behnken design. The predicted optimal conditions were 69.22 V, 6.89 min, and pH 4.35, yielding 37.5 μg azadirachtin per gram of pretreated seed.

Key findings

  • The optimal extraction conditions were 69.22 V, 6.89 min, and pH 4.35, with a response of 37.5 μg azadirachtin per gram of pretreated seed.
  • Quadratic and interaction effects were the most significant model effects (p < 0.0001); significant terms included voltage² (X1²), time² (X2²), pH² (X3²), voltage–pH (X1*X3), and time–pH (X2*X3).
  • The model had R² = 0.8375 and adjusted R² = 0.7957, with lack of fit p = 0.032.
  • Yield increased at 60–70 V to approximately 31–37.05 μg/g, decreased above 70 V to a minimum of 30.9 μg/g, peaked at 10 min extraction time, and decreased at pH above 5.

Methods

  • Neem fruits were collected in Puerto Colombia, Atlántico, Colombia, in October 2022 during the rainy season from 20 marked trees; seeds were dried, ground, and extracted using 10 g seed with 50 mL of 70% hydroethanolic solution at a 0.2 g/mL solid–liquid ratio, with pH adjusted to 4, 5, or 6 using 0.10 M HCl.
  • Microwave-assisted extraction was tested with magnetron voltage (60, 70, 80 V), extraction time (5, 10, 15 min), and pH (4, 5, 6) using a Box-Behnken design with 15 experimental combinations, conducted in triplicate.
  • Azadirachtin was quantified by UV-VIS spectrophotometry against a 95% azadirachtin standard; data were analyzed with a second-order regression model in RStudio using the “rms” package, with Levene’s test, two-way ANOVA, Tukey post hoc analysis, and canonical analysis at α = 0.05.

Limitations

  • The paper states that the model was not validated and that further studies are needed to understand the system and improve extraction efficiency for possible industrial application.
  • The paper states that the sample size was small because the study aimed to use material from the same tree, and that seasonal/exogenous factors such as rainy-season harvesting may have affected metabolite composition and yields.
  • Evident from the text: the study used a single collection location and season, did not perform independent model validation, and did not conduct range analysis because the optimum fell within the experimental region.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.heliyon.2024.e31504

Cites

48 of 49 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

8 of 48 cited sources checked · 1 supported · 0 flagged · accuracy not yet measured

  • Findingown data

    In the analysis of the linear and quadratic effects of extraction time, azadirachtin recovery increases with extraction time until a maximum at 10 min, then subsequently decreases.

    “Based on the analysis of the linear and quadratic effect of the extraction time as shown in Fig. 4, the results revealed that the recovery of azadirachtin increases when the extraction time increases until it reaches a maximum value (10 min) and then subsequently decreases.”
    Quote in the paperSubstantial claim
  • Findingown data

    In comparison with the experimental results, the amount of azadirachtin in the percentage of seed weight is equivalent to an approximate value of 0.04%.

    “In comparison with the results obtained experimentally, the amount of azadirachtin in the percentage of seed weight is equivalent to an approximate value of 0.04 %.”
    Quote in the paperNot a substantial claim
  • Findingown data

    At pH above 5, the extraction yield of azadirachtin decreases.

    “wherein it was observed that at a pH above 5, the extraction yield of azadirachtin decreases.”
    Quote in the paperSubstantial claim
  • Findingown data

    The optimal conditions found were 69.22 V, 6.89 min, and pH 4.35.

    “The optimal conditions found were as follows: 69.22 V, 6.89 min, and pH value of 4.35.”
    Quote in the paperSubstantial claim
  • Findingown data

    The interactions shown in Fig. 2 (B and E) and Fig. 2 (C and F) were more significant than those in Fig. 2 (A and D).

    “through the interaction between the study variables, it was shown that the existing interactions of Fig. 2 (B and E), and Fig. 2 (C and F) were more significant than that observed in Fig. 2 (A and D).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 16
  • May combine two claims. 12

  • Classified as probably not a substantial claim.

    Premisecitation

    Most studies conducted on metabolite and oil extraction processes conform to second-order models.

    “Most studies conducted on metabolite and oil extraction processes conform to second-order models [26,32,33].”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [26] Suttiarporn, 2020, Microwave-assisted improved extraction and purification of anticancer nimbolide from Azadirachta indica (neem) leaves, Molecules source

      Section 2.3 (page unavailable) reports that this study fitted nimbolide extraction data with a second-order polynomial model. That supports one metabolite-extraction example, but the paper does not establish that most metabolite and oil extraction studies conform to such models. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [32] Olufemi Awolu, 2013, Optimization of two-step transesterification production of biodiesel from neem (Azadirachta indica) oil, Int. J. Energy Environ. Eng. source
    • cites [33] Azaroual, 2021, Optimization of the microwave-assisted extraction of simple phenolic compounds from grape skins and seeds, Agronomy source

      Section 2.5 (Experimental Design; page unavailable) says this study of phenolic-compound extraction used a second-order mathematical model. It does not establish that most metabolite and oil extraction studies conform to such models; the oil-extraction and prevalence parts of the claim are unsupported by this source. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Interpretationcitation

    At voltages above 70 V, the extraction temperature is high enough and azadirachtin is thermally degraded, because azadirachtin is a thermolabile compound.

    “Therefore, it is expected that under these conditions, the extraction temperature is high enough and the metabolite is thermally degraded, since azadirachtin is a thermolabile chemical compound [26,38,39].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [26] Suttiarporn, 2020, Microwave-assisted improved extraction and purification of anticancer nimbolide from Azadirachta indica (neem) leaves, Molecules source

      Results and Discussion §2.2 reports that higher microwave power raised extraction temperature and that high temperature might degrade thermally labile nimbolide. It does not establish that azadirachtin degrades under the citing paper’s conditions or at voltages above 70 V; the compound and operating parameter differ. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [38] Prakash Maran, 2013, Optimization of microwave assisted extraction of pectin from orange peel, Carbohydr. Polym. source
    • cites [39] Chemat, 2013 source

  • Classified as probably not a substantial claim.

    Premisecitation

    Depending on the nature of the components, pH is a critical factor influencing the solubility of the compounds of interest.

    “Depending on the nature of the components, pH is a critical factor influencing the solubility of the compounds of interest [47].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [47] Oancea, 2012, Effects of extraction conditions on bioactive anthocyanin content of Vaccinium corymbosum in the perspective of food applications source

      The Results and discussions section says acids affect anthocyanin stability and that higher temperature increases analyte solubility. It does not say that pH influences solubility. Searches for pH and solubility found no passage establishing the claimed relationship. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Azadirachtin was quantified using UV-VIS in accordance with the protocol published by Haq et al. (2017).

    “The quantification of azadirachtin was performed using the UV-VIS technique in accordance with the protocol published by Haq et al. (2017), [29].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Haq et al. (2017), [29] source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In microwave-assisted extraction, typical extraction times range from a few minutes to half an hour depending on the plant matrix, to avoid thermal degradation and oxidation during extraction.

    “the usual times in MAE are between a few minutes to half an hour depending on the plant matrix to avoid thermal degradation and oxidation during extraction [43].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [43] Tatke, 2011, An overview of microwave assisted extraction and its applications in herbal drug research, Res. J. Med. Plant source

      The paper’s overview passage (p. 21; page not separately labeled in the indexed copy) describes MAE as fast and says it protects thermolabile constituents. It does not give a usual extraction-time range of a few minutes to half an hour, tie that range to the plant matrix, or mention avoiding oxidation; searches for the time range and oxidation found no supporting passage. (LLM, conf=0.77)

      Experimental — accuracy not yet measured

  • Classified as probably not a substantial claim.

    Premisecitation

    For MAE-assisted extractions in hydroethanolic systems, it is essential to evaluate the effect of pH, extraction time, and voltage of the equipment used during extraction.

    “For MAE-assisted extractions in hydroethanolic systems, it is essential to evaluate the effect of pH, extraction time, and voltage of the equipment used during extraction [36,37]”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [36] González-Hernández, 2024, Factors that influence the extraction methods of terpenes from natural sources, Chem. Pap. source

      The Microwave-assisted extraction (MAE) section recommends optimizing power, temperature, and time, and discusses MAE using aqueous ethanol. It does not recommend evaluating pH or equipment voltage for hydroethanolic MAE: its discussion of pH concerns liquid-liquid extraction, while electrical potential concerns pulsed electric fields. Page numbers were not available in our copy. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [37] Belwal, 2020, Optimized microwave assisted extraction (MAE) of alkaloids and polyphenols from Berberis roots using multiple-component analysis, Sci. Rep. source

      The Multiple-component analysis and MAE methods sections show that the study evaluated solvent pH, irradiation time, and microwave power. However, it used methanol rather than a hydroethanolic solvent and varied microwave power, not equipment voltage. The paper therefore supports evaluating related extraction conditions, but not the claim as stated. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Lynn et al. (2015) reported that azadirachtin concentration during the first 14 days of the stability test was approximately 55.9% at pH 4 and 54.3% at pH 6.

    “The data reported by Lynn et al. (2015) [50], revealed that the azadirachtin concentration during the first 14 days of the stability test was approximately 55.9 % at pH 4 and 54.3 % at pH 6.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [50] Lynn, 2015, The analysis of azadirachtin in two commercial formulations and study on their degradation under different temperature and pH condition by using high performance liquid chromatographic method, J. Agric. Res.

  • May combine two claims.

    Premisecitation

    RSM can generate a robust mathematical model that accounts for interrelationships among variables and minimizes the number of experiments.

    “the advantages of RSM are based on the ability to generate a robust mathematical model that takes into account the possible interrelationships of the variables to be evaluated and minimizes the number of experiments [4,5].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [4] Liyana-Pathirana, 2005, Optimization of extraction of phenolic compounds from wheat using response surface methodology, Food Chem. source
    • cites [5] Song, 2011, Optimized microwave-assisted extraction of total phenolics (TP) from Ipomoea batatas leaves and its antioxidant activity, Innovat. Food Sci. Emerg. Technol. source

  • May combine two claims.

    Premisecitation

    Azadirachtin is unstable in slightly alkaline and strongly acidic solutions.

    “Azadirachtin is unstable in slightly alkaline and strongly acidic solutions”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [49] Ujváry, 2010 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Longer irradiation time generally increases the extraction of essential oil and/or secondary metabolite and thus increases yield.

    “It is expected that the longer the irradiation time, the higher the extraction of the essential oil and/or secondary metabolite and thus the higher the yield”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [45] Alara, 2018, Vernonia cinerea leaves as the source of phenolic compounds, antioxidants, and anti-diabetic activity using microwave-assisted extraction technique, Ind. Crops Prod. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    Homogeneity of variances was estimated using Levene's test.

    “The study experiments were conducted in triplicate, data were presented as mean and standard deviation, homogeneity of variances was estimated with Levene's test, and a two-way ANOVA with Tukey's pot hoc analysis was performed to identify the experimental conditions that allowed us to find the highest extraction yield and to analyze whether the response surface model adequately describes our data.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    The R2 and R2 adj obtained (0.836 and 0.794, respectively) support the acceptability of the model and allow its use for optimization purposes.

    “The R2 and R2 adj obtained (0.836 and 0.794, respectively) support the acceptability of the model and allow its use for optimization purposes since the mathematical model fits above 70 % of the response behavior in terms of the R2 adj as established by Cheok et al. (2012), [6].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Cheok et al. (2012), [6] source

  • May combine two claims.

    Premisecitation

    Applying a higher voltage raises the temperature of the system because of higher microwave transmission, thus accelerating the heating process.

    “The application of a higher voltage will raise the temperature of the system because of the higher microwave transmission, thus accelerating the heating process [38,39].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [38] Prakash Maran, 2013, Optimization of microwave assisted extraction of pectin from orange peel, Carbohydr. Polym. source
    • cites [39] Chemat, 2013 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    MAE is known for reduced use of organic solvents compared with conventional extraction methods.

    “is known for its reduced use of organic solvents compared with conventional extraction methods [11].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [11] Rubio García, 2018, Extracción de compuestos bioactivos mediante pretratamiento con microondas de subproductos vitivinícolas. Valorización del raspón de la uva, Tesis, Universidad de Valladolid

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Premisecitation

    Response surface is a set of techniques whose purpose is to optimize the response surface influenced by different variables that can affect a process.

    “being the response surface a set of techniques whose purpose is to optimize the response surface that is influenced by different variables that can affect a process [52].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [52] Martínez, 2009, Application of response surface methodology for the optimization of welding parameters as a function of the resulting thermal distribution

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    MAE combined with RSM has advantages compared with other advanced extraction technologies, including higher extraction yield, improved selectivity, better handling, and low solvent consumption.

    “MAE combined with RSM has several advantages compared with other advanced extraction technologies, such as higher extraction yield, improved selectivity, better handling, and low solvent consumption [12].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [12] Mirzadeh, 2020, Antioxidant, antiradical, and antimicrobial activities of polysaccharides obtained by microwave-assisted extraction method: a review, Carbohydr. Polym. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    Since the fruits were harvested during the rainy season, it was presumed that the conditions affected the composition of neem metabolites and therefore yields were not found.

    “Since the fruits were harvested during the rainy season, it was presumed that the conditions affected the composition of neem metabolites and therefore yields were not found [19,55,56].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [19] Arias, 2009, Determinación del Azadiractina de los aceites esenciales del árbol de Neem (Azadirachta Indica), Revista Ingeniería UC
    • cites [55] Macías Alvarado

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [56] Arango Bedoya, 2012, Efecto del origen, la época de recolección y la edad de las hojas en el rendimiento y el contenido de timol de aceites esenciales de Lippia origanoides H.B.K, Acta Agron.

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data

    A two-way ANOVA with Tukey's post hoc analysis was performed to identify the experimental conditions with the highest extraction yield and to analyze whether the response surface model adequately described the data.

    “The study experiments were conducted in triplicate, data were presented as mean and standard deviation, homogeneity of variances was estimated with Levene's test, and a two-way ANOVA with Tukey's pot hoc analysis was performed to identify the experimental conditions that allowed us to find the highest extraction yield and to analyze whether the response surface model adequately describes our data.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Premisecitation

    The design and analysis of experiments are crucial in engineering to improve the performance of a process or system, especially to establish conditions for higher economic and operational performance.

    “The design and analysis of the experiments are crucial in the field of engineering, since they help to improve the performance of a process or system [51]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [51] Cabrera Castro

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim.

    Study design and conductown data

    The study experiments were conducted in triplicate.

    “The study experiments were conducted in triplicate, data were presented as mean and standard deviation, homogeneity of variances was estimated with Levene's test, and a two-way ANOVA with Tukey's pot hoc analysis was performed to identify the experimental conditions that allowed us to find the highest extraction yield and to analyze whether the response surface model adequately describes our data.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The BBD requires a smaller number of trials and provides reliable information in a shorter operation time.

    “the BBD was applied because it requires a smaller number of trials and provides reliable information in a shorter operation time [8].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [8] Dahmoune, 2014, Pistacia lentiscus leaves as a source of phenolic compounds: microwave-assisted extraction optimized and compared with ultrasound-assisted and conventional solvent extraction, Ind. Crops Prod. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Dai (1999) found a growth trend in microwave-assisted extraction of azadirachtin from minute 3 to minute 10 and a subsequent decrease.

    “His research on the optimization of the microwave-assisted extraction of azadirachtin found a growth trend from minute 3 to minute 10 and a subsequent decrease.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [46] Dai, 1999, Extraction and colorimetric determination of azadirachtin-related limonoids in neem seed kernel, J. Agric. Food Chem. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The extraction efficiency of secondary metabolites depends on multiple factors, the most relevant being the nature of the plant material, polarity of the solvent, temperature, particle size generated during grinding, and extraction technique used.

    “In general, the extraction efficiency of secondary metabolites depends on multiple factors, the most relevant being the nature of the plant material, polarity of the solvent, temperature, particle size generated during grinding, and extraction technique used, among others. These effects can be manifested independently or in combination [26,[34], [35], [36]].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [26,[34], [35], [36]]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Solvents with high dielectric constants can heat up quickly, making short extraction times convenient.

    “Since solvents with high dielectric constants can heat up quickly, it was convenient to use short extraction times [44]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [44] Chan, 2011, Microwave-assisted extractions of active ingredients from plants, J. Chromatogr. A source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    These findings are consistent with those of the present study and strengthen the hypothesis of low yields.

    “Furthermore, these findings are consistent with those of the present study and strengthen the hypothesis of low yields.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The sample size used for the experiments is one of the reasons why a good recovery was not obtained.
25 of 25

  • The authors state this as an assumption.

    Conditions for extracting neem seed oil in hydroethanolic media by MAE-assisted RSM with a BBD have not been reported.

    “but, to our knowledge, the conditions for extracting neem seed oil in hydroethanolic media by MAE-assisted RSM with a BBD have not been reported.”

  • The authors state this as an assumption.

    The effect of pH, extraction time, and voltage have not been reported for RSM optimization processes using a BBD.

    “since to date they have not been reported for RSM optimization processes using a BBD.”

  • The paper relies on this without support.

    Existing extraction conditions for RSM and MAE methods tend to consume high volumes of organic solvent and long extraction times.

    “However, the extraction conditions for these methods tend to consume high volumes of organic solvent and long extraction times.”

  • The paper relies on this without support.

    The sample size used for the experiments is one of the reasons why a good recovery was not obtained.

    “One of the reasons why a good recovery was not obtained is the sample size used for the experiments.”
4 of 4

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Azadirachtin yield is overstated as a percentage of seed weight

    Major

    A yield of 37.5 μg per gram of seed is 0.00375% by weight, not approximately 0.04%. It is also below, rather than above, both cited yields of 0.015% and 0.035%.

  • The voltage-pH interaction F-value does not match the ANOVA mean squares

    Minor

    The listed interaction mean square divided by the listed pure-error mean square is about 13.64, not 3.012. Even using the pooled residual mean square implied by the other regression F-values gives about 9.78, so the reported F-value is inconsistent with the table.

    Reported 3.012 · recomputed 13.636364

2 of 2

Cited works that were retracted

Works this paper cites that were later retracted, from the retraction notices publishers deposit. Major when the notice came out before this paper was published.

  • Cites a retracted work: 10.1155/2022/1790826

    Major

    The cited work was retracted on 2023-10-11 (notice 10.1155/2023/9897156), before this paper was published (2024-05). Its authors could have known.

    Cited work 10.1155/2022/1790826 · retracted 2023-10-11 · notice 10.1155/2023/9897156 · this paper published 2024-05

1 of 1

Cites

1 retracted

Flagged first, then by citations

Research works printed but not linked: 4

  1. Valcárcel Cases, 1988, Técnicas analíticas de separación, Reverté, Barcelona
  2. Rubio García, 2018, Extracción de compuestos bioactivos mediante pretratamiento con microondas de subproductos vitivinícolas. Valorización del raspón de la uva, Tesis, Universidad de Valladolid
  3. Roopashree, 2019, Advanced method of secondary metabolite extraction and quality analysis, J. Pharmacogn. Phytochem., 8, 1829
  4. Ujváry, 2010, vol. 11, 119

Cited by

Sorted by citations

Related

Authors
Martínez-Castro, R., Flórez-Santiago, J., Valle-Molinares, R., Cabrera-Barraza, J., & Espitia-Almeida, F.
Affiliations
  • Universidad del Atlántico (CO)
  • Universidad Simón Bolívar (CO)
Corresponding author
Espitia-Almeida, Fabián
ORCID
Venue
Heliyon
Publisher
Elsevier BV
Published
2024-05
Volume
10
Issue
10
Pages
e31504
ISSN
2405-8440 (ISSN-L)
DOI
10.1016/j.heliyon.2024.e31504
PMC
PMC11145488
OpenAlex
W4397289803
Semantic Scholar
65e793ef8eb52a9aa417c07b73d844d8bec2918f
Cited by
6
References
45
Citations by year
2026: 1 · 2025: 4 · 2024: 1
FWCI
1.32
Type
journal article
Language
en
Open access
Licence
Locations
  • Heliyon (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by-nc)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Universidad Simón Bolívar
  • Universidad del Atlántico
Topics
  • Life Sciences › Agricultural and Biological Sciences › Plant Science › Insect Pest Control Strategies
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Phytochemical compounds biological activities
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Agricultural and Biological Research
Keywords
azadirachtin, microwave-assisted extraction, neem seeds, extraction optimization, response surface methodology, extraction conditions, insecticidal natural products

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Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-26.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-26.

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Statistics and arithmetic are recomputed, not judged.

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