Comparative assessment of volatiles in juices and essential oils from minor Citrus fruits (Rutaceae)

Abstract

Citrus Essential Oils (CEOs) from the peel of six minor Citrus fruits (C. bergamia 'Castagnaro,' 'Fantastico,' and 'Femminello,' C. × myrtifolia, C. mitis, and C. japonica) were obtained by hydrodistillation and cold hand pressing of the flavedo to investigate their volatile constituents and antimycotic activities. The volatile compounds present in the juices of the same fruits, obtained by manual squeezing of the endocarps, were evaluated by direct immersion and Solid Phase Micro Extraction. Monoterpenes were identified as the main class of components in all the six CEOs. Limonene was the most abundant compound, while BEOs (Bergamot Essential Oils) changed its composition according to the different extraction method and the fruit varieties. Non-metric Multidimensional Scaling (NMDS) of the matrix taxa x chemical compounds showed that five chemical compounds had a significant discriminative function among the samples: high amounts of limonene characterized the cluster of C japonica, C. × myrtifolia, and C mitis, while the group of three cultivars of C bergamia differed in its predominance of linalool and linalyl acetate. Furfural and 4-terpineol were identified in the highest amounts in the Citrus juices analyzed by direct immersion. BEO obtained by hydrodistillation of C bergamia 'Fantastico' was the most active in the antifungal tests. The antimycotic activity of C japonica EOs against dermatophytic species was also demonstrated. Based on our results, the use of these products would appear an interesting alternative in producing topical herbal products for the treatment of affected animals or for the purpose of environmental fungal control.

Use of Essential Oils in Veterinary Medicine to Combat Bacterial and Fungal Infections

“…In detail, Citrus limon EO was proven neither effective against M. canis [ 98 ] nor other dermatophytes [ 99 ], as well as its variety Pompia [ 114 ] and Citrus medica and Citrus bergamia [ 100 ]. Only one out of three cultivars of C. bergamia ( C. bergamia v. fantastico ), and Citrus japonica EOs would show a moderate activity (0.5%) versus M. canis , M. gypseum, and T. mentagrophytes , while Citrus × myrtifolia did not exert any antimycotic effect when tested at 10% [ 115 ]. Citrus spp.…”

“…O. majorana [ 198 ] and C. flexuosus [ 195 , 198 ] appeared quite effective, and the same MICs were obtained also by L. cubeba and C. bergamia EOs [ 198 ]. However, this latter EO exerted a stronger anti- Saprolegnia efficacy (0.5% versus 2.5%) in another study [ 115 ]. The most inhibiting effect was probably due to the higher contents of linalool.…”

Flavedo and albedo of five citrus fruits from Southern Italy: physicochemical characteristics and enzyme-assisted extraction of phenolic compounds

“…Most likely, albedo being highly porous materials [23,24] were made of less dense and lighter particles. On the contrary, flavedo being rich in oils [25] delivered particles that aggregated and formed bigger complexes. Regardless of the specific tissue, SA provided the fractions with the highest BD, whereas LE tissues performed conversely.…”

A Compositional Perspective of Sour Orange (Citrus aurantium L.) Flowers Essential Oil under Different Storage Conditions

“…The impact of light on the EO content was noticeable during three months of storage at room temperature, while a lower quantity was obtained in the presence of light than darkness (4.8% lesser), but higher quantities were observed at six and nine months in the presence of light, compared to darkness (27.8 and 21.6% more, respectively) (Table 1). β-pinene is responsible for the green odor in aromatic note assessments of citrus EOs [49]. Both optical antipodes of α-pinene are natural products, and they may co-occur with either isomer predominant.…”