Alginate-Assisted Lemongrass (Cymbopogon nardus) Essential Oil Dispersions for Antifungal Activity

Abstract

The use of natural compounds as food preservatives is becoming increasingly popular as it is perceived positively by consumers. Among these substances, essential oils have attracted great interest owing to their antioxidant and antimicrobial properties. However, several challenges impair the use of essential oils in food products, such as their degradation or loss during food processing and storage, the strong aroma, even at low concentrations, which may negatively affect the sensory characteristics of food. In this context, the development of nanoformulations able to stabilize essential oils may represent a smart solution to this issue. The aim of the study was to evaluate the efficiency of alginate-based nanoformulations enriched with lemongrass (Cymbopogon nardus) essential oil (LEO) and Tween 80 against several fungi namely Penicillium expansus, Aspergillus niger and Rhizopus spp. Firstly, the flow behavior of systems at different concentrations of alginate (1%, 2% and 3% w/w) were studied. Then, emulsion-based nanoformulations at different concentrations of lemongrass essential oil in the range of 0–2% w/w were stabilized by a fixed amount of Tween 80, characterized and tested for their antifungal activity. Our results showed that the best nanoformulation able to inhibit Rhizopus spp., Penicillium expansum and Aspergillus niger, for at least 10 days, was constituted by 1% alginate/1.5% LEO/1% Tween 80. Hence, the incorporation of essential oil into nanoformulation systems may represent a valid alternative to overcome the disadvantages that limit the commercial application of essential oils.

Essential Oil Composition Analysis of Cymbopogon Species from Eastern Nepal by GC-MS and Chiral GC-MS, and Antimicrobial Activity of Some Major Compounds

“…This study showed that the assayed root and leaves of C. winterianus EOs have variable microbial inhibitory activities, as presented in Table 6 . Plants having secondary metabolites and the EOs of C. winterianus have demonstrated a broad range of antimicrobial activities against different pathogens [ 11 , 12 , 49 , 50 ]. The leaf part of C. winterianus EO showed effectiveness against Pseudomonas aeruginosa , with an MIC of 78.1 μg/mL and noticeable activity against Staphylococcus aureus , Staphylococcus epidermidis , and Streptococcus pyogenes , with an MIC of 156.3 μg/mL, while other panels of bacterial strains had no surprising results.…”

Antifungal features and properties of Pickering emulsion coating from alginate/lemongrass oil/cellulose nanofibers

“…In this study, LGO‐containing samples demonstrated significant potential with antifungal action in active Alg coating, by inhibiting the spore germination of undesirable fungi. Similar results have been documented when LGO was entrapped in Alg matrix (Riquelme et al ., 2017; Gago et al ., 2019; Cofelice et al ., 2021; Kawhena et al ., 2021) and other matrices including chitosan (Shao et al ., 2015; Kawhena et al ., 2021) and starch (Perdana et al ., 2021). The active components, α‐citral (geranial) and β‐citral (neral), are believed to be potent antifungal agents contained in LGO (Lal et al ., 2016; Lal et al ., 2018).…”

“…Previous studies reported the antifungal ability of Alg/LGO emulsion composite against Penicillium spp (Cofelice et al ., 2021; Kawhena et al ., 2021), Botrytis cinerea (Riquelme et al ., 2017; Gago et al ., 2019; Kawhena et al ., 2021), Rhizopus spp. (Cofelice et al ., 2021) and Aspergillus niger (Cofelice et al ., 2021). Furthermore, Alg/LGO permitted as a generally recognised as safe (GRAS) compound with acceptable daily intake (ADI) value for geraniol of 0.5 mg kg −1 body weight day −1 (Commission Implementing Regulation (EU) No 570/, 2013).…”

“…LGO, a lemon‐like aroma, is characterised by potential active compounds comprising monoterpenes, among which citral exists as the major component at a level of 65%–85% as a mixture of isomeric forms including geranial (α‐citral) and neral (β‐citral) (da Silva Cde et al ., 2008; Tajidin, 2012; Dutta et al ., 2017; Munda et al ., 2019). Previous studies reported the antifungal ability of Alg/LGO emulsion composite against Penicillium spp (Cofelice et al ., 2021; Kawhena et al ., 2021), Botrytis cinerea (Riquelme et al ., 2017; Gago et al ., 2019; Kawhena et al ., 2021), Rhizopus spp. (Cofelice et al ., 2021) and Aspergillus niger (Cofelice et al ., 2021).…”

Essential Oils from Indigenous Iranian Plants: A Natural Weapon vs. Multidrug-Resistant Escherichia coli

“…In recent years, many researches have increasingly demonstrated the antimicrobial effect of different essential oils (such as cilantro, coriander, oregano, cinnamon, rosemary, sage, clove, thyme, etc.) against pathogenic bacteria and food spoilage agents [14][15][16][17] and have proposed new solutions to deliver these compounds [18,19]. Wang et al (2020) showed that ginger essential oil, where zingiberene and α-curcumene were identified as the main chemical constituents, has excellent antibacterial activity against E. coli and S. aureus [20].…”