Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

doi:10.1007/s13659-023-00417-9

Natural Products and Bioprospecting ›› 2024, Vol. 14 ›› Issue (1): 1-1.DOI: 10.1007/s13659-023-00417-9

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Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

Heloísa H. S. Almeida^1,2,3,4, Pedro J. L. Crugeira^1,2, Joana S. Amaral^1,2, Alírio E. Rodrigues^3,4, Maria-Filomena Barreiro^1,2

1. Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-252, Bragança, Portugal;
2. Laboratório Associado Para a Sustentabilidade Em Regiões de Montanha (SusTEC), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-252, Bragança, Portugal;
3. Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal;
4. Associate Laboratory in Chemical Engineering (ALiCE), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal

Received:2023-09-26 Online:2024-02-19 Published:2024-02-24
Contact: Maria-Filomena Barreiro,E-mail:barreiro@ipb.pt
Supported by:
Financial support through national funds FCT/MCTES (PIDDAC) to LSRE-LCM (UIDB/50020/2020 and UIDP/00690/2020), ALiCE (LA/P/0045/2020), CIMO (UIDB/00690/2020 and UIDP/00690/2020), and SusTEC (LA/P/0007/2021). FCT for the SFRH/BD/148124/2019 Heloísa Helena Scorsato de Almeida research grant. Pedro Crugeira thanks OleaChain (NORTE-06-3559-FSE14 000188) for his research contract. GreenHealth project (Norte-01-0145-FEDER-000042). Deifil Technology Lda (www.deifil.pt) for supplying the studied plants.

Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

Heloísa H. S. Almeida^1,2,3,4, Pedro J. L. Crugeira^1,2, Joana S. Amaral^1,2, Alírio E. Rodrigues^3,4, Maria-Filomena Barreiro^1,2

1. Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-252, Bragança, Portugal;
2. Laboratório Associado Para a Sustentabilidade Em Regiões de Montanha (SusTEC), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-252, Bragança, Portugal;
3. Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal;
4. Associate Laboratory in Chemical Engineering (ALiCE), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal

通讯作者: Maria-Filomena Barreiro,E-mail:barreiro@ipb.pt
基金资助:
Financial support through national funds FCT/MCTES (PIDDAC) to LSRE-LCM (UIDB/50020/2020 and UIDP/00690/2020), ALiCE (LA/P/0045/2020), CIMO (UIDB/00690/2020 and UIDP/00690/2020), and SusTEC (LA/P/0007/2021). FCT for the SFRH/BD/148124/2019 Heloísa Helena Scorsato de Almeida research grant. Pedro Crugeira thanks OleaChain (NORTE-06-3559-FSE14 000188) for his research contract. GreenHealth project (Norte-01-0145-FEDER-000042). Deifil Technology Lda (www.deifil.pt) for supplying the studied plants.

Abstract

Abstract: Antimicrobial resistance is a major global health concern, threatening the effective prevention and treatment of infections caused by microorganisms. These factors boosted the study of safe and green alternatives, with hydrosols, the by-products of essential oils extraction, emerging as promising natural antimicrobial agents. In this context, four hydrosols obtained from Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu and Melissa officinalis L. were studied. Their chemical composition comprises neral, geranial, 1,8-cineole, terpinen-4-ol, and oplopanonyl acetate, compounds with recognised antimicrobial activity. Concerning antimicrobial activity, significant differences were found using different hydrosol concentrations (10–20% v/v) in comparison to a control (without hydrosol), showing the potential of the tested hydrosols to inhibit the microbial growth of Escherichia coli, Staphylococcus aureus, and Candida albicans. A. citrodora hydrosol was the most effective one, inhibiting 90% of E. coli growth and 80% of C. albicans growth, for both hydrosol concentrations (p < 0.0001). With hydrosol concentration increase, it was possible to observe an improved antimicrobial activity with significant reductions (p < 0.0001). The findings of this work indicate the viability of reusing and valuing the hydrosols, encouraging the development of green applications for different fields (e.g., food, agriculture, pharmaceuticals, and cosmetics).

Key words: Hydrosols, Essential oil by-products, Chemical composition, Antimicrobial activity, Natural preservatives, Waste valorisation

摘要： Antimicrobial resistance is a major global health concern, threatening the effective prevention and treatment of infections caused by microorganisms. These factors boosted the study of safe and green alternatives, with hydrosols, the by-products of essential oils extraction, emerging as promising natural antimicrobial agents. In this context, four hydrosols obtained from Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu and Melissa officinalis L. were studied. Their chemical composition comprises neral, geranial, 1,8-cineole, terpinen-4-ol, and oplopanonyl acetate, compounds with recognised antimicrobial activity. Concerning antimicrobial activity, significant differences were found using different hydrosol concentrations (10–20% v/v) in comparison to a control (without hydrosol), showing the potential of the tested hydrosols to inhibit the microbial growth of Escherichia coli, Staphylococcus aureus, and Candida albicans. A. citrodora hydrosol was the most effective one, inhibiting 90% of E. coli growth and 80% of C. albicans growth, for both hydrosol concentrations (p < 0.0001). With hydrosol concentration increase, it was possible to observe an improved antimicrobial activity with significant reductions (p < 0.0001). The findings of this work indicate the viability of reusing and valuing the hydrosols, encouraging the development of green applications for different fields (e.g., food, agriculture, pharmaceuticals, and cosmetics).

关键词: Hydrosols, Essential oil by-products, Chemical composition, Antimicrobial activity, Natural preservatives, Waste valorisation

Heloísa H. S. Almeida, Pedro J. L. Crugeira, Joana S. Amaral, Alírio E. Rodrigues, Maria-Filomena Barreiro. Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents[J]. Natural Products and Bioprospecting, 2024, 14(1): 1-1.

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Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

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