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Antonio Seguracarretero - One of the best experts on this subject based on the ideXlab platform.

  • design of sonotrode ultrasound assisted extraction of phenolic compounds from psidium guajava l leaves
    Food Analytical Methods, 2017
    Co-Authors: Elixabet Diazdecerio, Urszula Tylewicz, Alberto Fernandezgutierrez, Antonio Seguracarretero, Vito Verardo, Santina Romani
    Abstract:

    Psidium guajava L. has gained a special attention as health plant due to the presence of phenolic compounds. Box-Behnken design (BBD) has been applied for the extraction of target compounds from guava leaves via sonotrode ultrasound-assisted extraction (UAE). Different extraction times (5, 30, and 55 min), ratios of ethanol/water (50, 75, and 100% (v/v)), and ultrasound (US) power (80, 240, and 400 W) were tested to find their effect on the sum of phenolic compound (SPC), flavonols and flavan-3-ols via HPLC-ESI-QqQ-MS, and antioxidant activity (DPPH and TEAC assays). The best process conditions were as follows: 40 min, 60% ethanol/water (v/v), and 200 W. Established method has been used to extract phenolic compounds in two guava leaves varieties (pyrifera and pomifera). Pyrifera var. showed greater values of the SPC via HPLC-ESI-QqQ-MS (49.7 mg/g leaf dry weight (d.w.)), flavonols (12.51 mg/g d.w.), flavan-3-ols (7.20 mg/g d.w.), individual phenolic compounds, and antioxidant activity (8970 ± 5 and 465 ± 6 μmol Trolox/g leaf d.w, respectively) than pomifera var. Conventional extraction showed lower amounts of phenolic compounds (7.81 ± 0.03 and 4.64 ± 0.01 mg/g leaf d.w. for flavonols and flavan-3ols, respectively) in comparison to the ultrasound-assisted ones.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.

Olga Tzakou - One of the best experts on this subject based on the ideXlab platform.

  • chemical composition and larvicidal evaluation of mentha salvia and melissa essential oils against the west nile virus mosquito culex pipiens
    Parasitology Research, 2010
    Co-Authors: George Koliopoulos, E Kioulos, Antonios Michaelakis, Danae Pitarokili, Olga Tzakou
    Abstract:

    The volatile metabolites of wild-growing Mentha spicata, M. longifolia, M. suaveolens, Melissa officinalis, Salvia fruticosa, S. pomifera subsp. calycina, and S. pomifera subsp. pomifera from Greece were determined by gas chromatography and gas chromatography–mass spectrometry. The insecticidal properties of the analyzed essential oils were screened on Culex pipiens larvae. Additionally two of the main components of the essential oils, piperitenone oxide and 1,8-cineole were assayed against C. pipiens in order to define the affiliation between them and the larvicidal properties of the oils. The most effective oils were M. suaveolens (major constituent piperitenone oxide, 62.4%), M. spicata (piperitenone oxide, 35.7% and 1,8-cineole, 14.5%) and M. longifolia—Central Greece (piperitenone oxide, 33.4%; 1,8-cineole, 24.5% and trans-piperitone epoxide, 17.4%), which exhibited LC50 values ranging from 47.88 to 59.33 mg l−1. Medium activity revealed the oils of M. officinalis (terpin-4-ol, 15.8%; caryophyllene oxide, 13.2%; sabinene, 12.9%; β-pinene, 12.1%; and trans-caryophyllene, 10.2%), M. longifolia—Southern Greece (carvone, 54.7% and limonene 20.0%), S. pomifera subsp. pomifera (trans-caryophyllene, 22.5% and trans-thujone, 21.0%), S. pomifera subsp. calycina—West Southern Greece (trans-thujone, 56.1% and 1,8-cineole, 10.4%), and S. fruticosa—population 2 (camphor, 23.1%; α-pinene, 12.7%; and borneol, 12.6%), with LC50 values ranging from 78.28 to 91.45 mg l−1. S. pomifera subsp. calycina (Central Greece) essential oil (trans-thujone, 26.5% and cis-thujone, 12.0%) presented rather low activity (LC50 values 140.42 mg l−1), while S. fruticosa—population 1 (1,8-cineole, 31.4% and camphor, 22.6%) was the only inactive oil. Additionally, the constituent piperitenone oxide was found to be highly active (LC50 values 9.95 mg l−1), whereas 1,8-cineole revealed no toxicity.

  • Chemical composition and larvicidal evaluation of Mentha, Salvia, and Melissa essential oils against the West Nile virus mosquito Culex pipiens
    Parasitology research, 2010
    Co-Authors: George Koliopoulos, E Kioulos, Antonios Michaelakis, Danae Pitarokili, Olga Tzakou
    Abstract:

    The volatile metabolites of wild-growing Mentha spicata, M. longifolia, M. suaveolens, Melissa officinalis, Salvia fruticosa, S. pomifera subsp. calycina, and S. pomifera subsp. pomifera from Greece were determined by gas chromatography and gas chromatography-mass spectrometry. The insecticidal properties of the analyzed essential oils were screened on Culex pipiens larvae. Additionally two of the main components of the essential oils, piperitenone oxide and 1,8-cineole were assayed against C. pipiens in order to define the affiliation between them and the larvicidal properties of the oils. The most effective oils were M. suaveolens (major constituent piperitenone oxide, 62.4%), M. spicata (piperitenone oxide, 35.7% and 1,8-cineole, 14.5%) and M. longifolia--Central Greece (piperitenone oxide, 33.4%; 1,8-cineole, 24.5% and trans-piperitone epoxide, 17.4%), which exhibited LC(50) values ranging from 47.88 to 59.33 mg l(-1). Medium activity revealed the oils of M. officinalis (terpin-4-ol, 15.8%; caryophyllene oxide, 13.2%; sabinene, 12.9%; beta-pinene, 12.1%; and trans-caryophyllene, 10.2%), M. longifolia--Southern Greece (carvone, 54.7% and limonene 20.0%), S. pomifera subsp. pomifera (trans-caryophyllene, 22.5% and trans-thujone, 21.0%), S. pomifera subsp. calycina--West Southern Greece (trans-thujone, 56.1% and 1,8-cineole, 10.4%), and S. fruticosa--population 2 (camphor, 23.1%; alpha-pinene, 12.7%; and borneol, 12.6%), with LC(50) values ranging from 78.28 to 91.45 mg l(-1). S. pomifera subsp. calycina (Central Greece) essential oil (trans-thujone, 26.5% and cis-thujone, 12.0%) presented rather low activity (LC(50) values 140.42 mg l(-1)), while S. fruticosa--population 1 (1,8-cineole, 31.4% and camphor, 22.6%) was the only inactive oil. Additionally, the constituent piperitenone oxide was found to be highly active (LC(50) values 9.95 mg l(-1)), whereas 1,8-cineole revealed no toxicity.

Elixabet Diazdecerio - One of the best experts on this subject based on the ideXlab platform.

  • design of sonotrode ultrasound assisted extraction of phenolic compounds from psidium guajava l leaves
    Food Analytical Methods, 2017
    Co-Authors: Elixabet Diazdecerio, Urszula Tylewicz, Alberto Fernandezgutierrez, Antonio Seguracarretero, Vito Verardo, Santina Romani
    Abstract:

    Psidium guajava L. has gained a special attention as health plant due to the presence of phenolic compounds. Box-Behnken design (BBD) has been applied for the extraction of target compounds from guava leaves via sonotrode ultrasound-assisted extraction (UAE). Different extraction times (5, 30, and 55 min), ratios of ethanol/water (50, 75, and 100% (v/v)), and ultrasound (US) power (80, 240, and 400 W) were tested to find their effect on the sum of phenolic compound (SPC), flavonols and flavan-3-ols via HPLC-ESI-QqQ-MS, and antioxidant activity (DPPH and TEAC assays). The best process conditions were as follows: 40 min, 60% ethanol/water (v/v), and 200 W. Established method has been used to extract phenolic compounds in two guava leaves varieties (pyrifera and pomifera). Pyrifera var. showed greater values of the SPC via HPLC-ESI-QqQ-MS (49.7 mg/g leaf dry weight (d.w.)), flavonols (12.51 mg/g d.w.), flavan-3-ols (7.20 mg/g d.w.), individual phenolic compounds, and antioxidant activity (8970 ± 5 and 465 ± 6 μmol Trolox/g leaf d.w, respectively) than pomifera var. Conventional extraction showed lower amounts of phenolic compounds (7.81 ± 0.03 and 4.64 ± 0.01 mg/g leaf d.w. for flavonols and flavan-3ols, respectively) in comparison to the ultrasound-assisted ones.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.

George Koliopoulos - One of the best experts on this subject based on the ideXlab platform.

  • chemical composition and larvicidal evaluation of mentha salvia and melissa essential oils against the west nile virus mosquito culex pipiens
    Parasitology Research, 2010
    Co-Authors: George Koliopoulos, E Kioulos, Antonios Michaelakis, Danae Pitarokili, Olga Tzakou
    Abstract:

    The volatile metabolites of wild-growing Mentha spicata, M. longifolia, M. suaveolens, Melissa officinalis, Salvia fruticosa, S. pomifera subsp. calycina, and S. pomifera subsp. pomifera from Greece were determined by gas chromatography and gas chromatography–mass spectrometry. The insecticidal properties of the analyzed essential oils were screened on Culex pipiens larvae. Additionally two of the main components of the essential oils, piperitenone oxide and 1,8-cineole were assayed against C. pipiens in order to define the affiliation between them and the larvicidal properties of the oils. The most effective oils were M. suaveolens (major constituent piperitenone oxide, 62.4%), M. spicata (piperitenone oxide, 35.7% and 1,8-cineole, 14.5%) and M. longifolia—Central Greece (piperitenone oxide, 33.4%; 1,8-cineole, 24.5% and trans-piperitone epoxide, 17.4%), which exhibited LC50 values ranging from 47.88 to 59.33 mg l−1. Medium activity revealed the oils of M. officinalis (terpin-4-ol, 15.8%; caryophyllene oxide, 13.2%; sabinene, 12.9%; β-pinene, 12.1%; and trans-caryophyllene, 10.2%), M. longifolia—Southern Greece (carvone, 54.7% and limonene 20.0%), S. pomifera subsp. pomifera (trans-caryophyllene, 22.5% and trans-thujone, 21.0%), S. pomifera subsp. calycina—West Southern Greece (trans-thujone, 56.1% and 1,8-cineole, 10.4%), and S. fruticosa—population 2 (camphor, 23.1%; α-pinene, 12.7%; and borneol, 12.6%), with LC50 values ranging from 78.28 to 91.45 mg l−1. S. pomifera subsp. calycina (Central Greece) essential oil (trans-thujone, 26.5% and cis-thujone, 12.0%) presented rather low activity (LC50 values 140.42 mg l−1), while S. fruticosa—population 1 (1,8-cineole, 31.4% and camphor, 22.6%) was the only inactive oil. Additionally, the constituent piperitenone oxide was found to be highly active (LC50 values 9.95 mg l−1), whereas 1,8-cineole revealed no toxicity.

  • Chemical composition and larvicidal evaluation of Mentha, Salvia, and Melissa essential oils against the West Nile virus mosquito Culex pipiens
    Parasitology research, 2010
    Co-Authors: George Koliopoulos, E Kioulos, Antonios Michaelakis, Danae Pitarokili, Olga Tzakou
    Abstract:

    The volatile metabolites of wild-growing Mentha spicata, M. longifolia, M. suaveolens, Melissa officinalis, Salvia fruticosa, S. pomifera subsp. calycina, and S. pomifera subsp. pomifera from Greece were determined by gas chromatography and gas chromatography-mass spectrometry. The insecticidal properties of the analyzed essential oils were screened on Culex pipiens larvae. Additionally two of the main components of the essential oils, piperitenone oxide and 1,8-cineole were assayed against C. pipiens in order to define the affiliation between them and the larvicidal properties of the oils. The most effective oils were M. suaveolens (major constituent piperitenone oxide, 62.4%), M. spicata (piperitenone oxide, 35.7% and 1,8-cineole, 14.5%) and M. longifolia--Central Greece (piperitenone oxide, 33.4%; 1,8-cineole, 24.5% and trans-piperitone epoxide, 17.4%), which exhibited LC(50) values ranging from 47.88 to 59.33 mg l(-1). Medium activity revealed the oils of M. officinalis (terpin-4-ol, 15.8%; caryophyllene oxide, 13.2%; sabinene, 12.9%; beta-pinene, 12.1%; and trans-caryophyllene, 10.2%), M. longifolia--Southern Greece (carvone, 54.7% and limonene 20.0%), S. pomifera subsp. pomifera (trans-caryophyllene, 22.5% and trans-thujone, 21.0%), S. pomifera subsp. calycina--West Southern Greece (trans-thujone, 56.1% and 1,8-cineole, 10.4%), and S. fruticosa--population 2 (camphor, 23.1%; alpha-pinene, 12.7%; and borneol, 12.6%), with LC(50) values ranging from 78.28 to 91.45 mg l(-1). S. pomifera subsp. calycina (Central Greece) essential oil (trans-thujone, 26.5% and cis-thujone, 12.0%) presented rather low activity (LC(50) values 140.42 mg l(-1)), while S. fruticosa--population 1 (1,8-cineole, 31.4% and camphor, 22.6%) was the only inactive oil. Additionally, the constituent piperitenone oxide was found to be highly active (LC(50) values 9.95 mg l(-1)), whereas 1,8-cineole revealed no toxicity.

Vito Verardo - One of the best experts on this subject based on the ideXlab platform.

  • design of sonotrode ultrasound assisted extraction of phenolic compounds from psidium guajava l leaves
    Food Analytical Methods, 2017
    Co-Authors: Elixabet Diazdecerio, Urszula Tylewicz, Alberto Fernandezgutierrez, Antonio Seguracarretero, Vito Verardo, Santina Romani
    Abstract:

    Psidium guajava L. has gained a special attention as health plant due to the presence of phenolic compounds. Box-Behnken design (BBD) has been applied for the extraction of target compounds from guava leaves via sonotrode ultrasound-assisted extraction (UAE). Different extraction times (5, 30, and 55 min), ratios of ethanol/water (50, 75, and 100% (v/v)), and ultrasound (US) power (80, 240, and 400 W) were tested to find their effect on the sum of phenolic compound (SPC), flavonols and flavan-3-ols via HPLC-ESI-QqQ-MS, and antioxidant activity (DPPH and TEAC assays). The best process conditions were as follows: 40 min, 60% ethanol/water (v/v), and 200 W. Established method has been used to extract phenolic compounds in two guava leaves varieties (pyrifera and pomifera). Pyrifera var. showed greater values of the SPC via HPLC-ESI-QqQ-MS (49.7 mg/g leaf dry weight (d.w.)), flavonols (12.51 mg/g d.w.), flavan-3-ols (7.20 mg/g d.w.), individual phenolic compounds, and antioxidant activity (8970 ± 5 and 465 ± 6 μmol Trolox/g leaf d.w, respectively) than pomifera var. Conventional extraction showed lower amounts of phenolic compounds (7.81 ± 0.03 and 4.64 ± 0.01 mg/g leaf d.w. for flavonols and flavan-3ols, respectively) in comparison to the ultrasound-assisted ones.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.

  • determination of guava psidium guajava l leaf phenolic compounds using hplc dad qtof ms
    Journal of Functional Foods, 2016
    Co-Authors: Elixabet Diazdecerio, Ana Maria Gomezcaravaca, Alberto Fernandezgutierrez, Vito Verardo, Antonio Seguracarretero
    Abstract:

    Abstract Markets of different countries have proposed guava tea infusions as a drink that can modulate the glycaemic index in blood. This property has been attributed to the phenolic compounds contained in guava leaves. However, phenolic profile of guava leaves is still not well-known. Based on this information, different ethanol/water mixtures were used to extract the phenolic compounds in guava leaves. Phenolic identification was carried out by HPLC-ESI-QTOF-MS in guava leaves from pomifera and pyrifera varieties; moreover, the antioxidant activities of the ethanolic extracts were determined by TEAC and FRAP methods. To sum up, seventy-two phenolic compounds were identified. To our knowledge, twelve of them were determined for the first time in guava leaves. The highest amount of phenolic compounds was found in EtOH/H2O 80:20 (v/v) mixture. Furthermore, pyrifera var. showed higher concentration of phenolic compounds than pomifera var. (113.34 vs. 86.12 mg/g leaf d.w.) and also greater antioxidant capacity.