The present study aimed to chemically characterize 31 accessions and seven cultivars of basil. The percentage composition of the essential oils of the accessions and cultivars was based on the 14 most abundant constituents: 1,8-cineole, linalool, methyl chavicol, neral, nerol, geraniol, geranial, methyl cinnamate,
The genus
Basil (
Basil has a complicated taxonomy due to the numerous varieties of cultivars within the species that do not differ significantly in morphology. Thus, the classification of genotypes only by morphological features becomes difficult due to anthropogenic interference with selection, cultivation, and hybridization [
Genotype characterization based on the chemical constitution of the essential oil has been used in several cultures such as
A total of 27 basil cultivars were characterized according to the chemical composition of their essential oils, and the cultivars were grouped into five different types: eugenol/linalool (30–35% linalool and 12–20% eugenol); linalool (52–66%); estragole/linalool (22–38% estragole and 21–37% linalool);
The chemical characterization of 38 basil genotypes resulted in seven groups: linalool (19–73%); linalool/eugenol (28–66% linalool and 5–29% eugenol); methyl chavicol (20–72% methyl chavicol); methyl chavicol/linalool (8–29% methyl chavicol and 8–53% linalool); methyl eugenol/linalool (two accessions with 37% and 91% methyl eugenol and 60% and 15% linalool); methyl cinnamate/linalool (9.7% methyl cinnamate and 31% linalool); and bergamotene (one accession with bergamotene as the major constituent) [
Morphological and agronomic characterization of 55 basil accessions showed genetic variability in
These comparative studies show a high variation in the chemical composition of basil essential oil and how important it is to conduct research investigating these chemical characterizations because the identification of types of basil helps in pharmacological, medicinal, and phytopathological studies. Thus, the present study aimed to chemically characterize the volatile constituents of accessions and cultivars of
The experiment was conducted at the Experimental Farm “Rural Campus of the UFS.” A randomized complete block design with two repetitions was used to evaluate 38 genotypes of
Identification and origin of analysed basil accessions and cultivars.
Accession | Species | Origin |
---|---|---|
NSL 6421 |
|
North Central Regional PI Station |
PI 170579 |
|
North Central Regional PI Station |
PI 170581 |
|
North Central Regional PI Station |
PI 172996 |
|
North Central Regional PI Station |
PI 172997 |
|
North Central Regional PI Station |
PI 174285 |
|
North Central Regional PI Station |
PI 176646 |
|
North Central Regional PI Station |
PI 182246 |
|
North Central Regional PI Station |
PI 197442 |
|
North Central Regional PI Station |
PI 207498 |
|
North Central Regional PI Station |
PI 211586 |
|
North Central Regional PI Station |
PI 253157 |
|
North Central Regional PI Station |
PI 296390 |
|
North Central Regional PI Station |
PI 296391 |
|
North Central Regional PI Station |
PI 358464 |
|
North Central Regional PI Station |
PI 358466 |
|
North Central Regional PI Station |
PI 358467 |
|
North Central Regional PI Station |
PI 358471 |
|
North Central Regional PI Station |
PI 358472 |
|
North Central Regional PI Station |
PI 368697 |
|
North Central Regional PI Station |
PI 368698 |
|
North Central Regional PI Station |
PI 368699 |
|
North Central Regional PI Station |
PI 368700 |
|
North Central Regional PI Station |
PI 379414 |
|
North Central Regional PI Station |
PI 414193 |
|
North Central Regional PI Station |
PI 414194 |
|
North Central Regional PI Station |
PI 414196 |
|
North Central Regional PI Station |
PI 414197 |
|
North Central Regional PI Station |
PI 414198 |
|
North Central Regional PI Station |
PI 414199 |
|
North Central Regional PI Station |
PI 414200 |
|
North Central Regional PI Station |
“Genovese” |
|
Topseed (Brazil) |
“Sweet Dani” |
|
Johnny’s Selected Seeds Co |
“Cinnamon” |
|
Johnny’s Selected Seeds Co. |
“Fino Verde” |
|
Johnny’s Selected Seeds Co. |
“Red Rubin” |
|
Johnny’s Selected Seeds Co. |
“Osmin Purple” |
|
Johnny’s Selected Seeds Co. |
“Italian Large Leaf” |
|
Johnny’s Selected Seeds Co. |
The seedlings were grown in a greenhouse with a 50% shading screen in polystyrene trays with 128 alveoli. The substrate mixture used was composed of coconut powder, cattle manure, and carbonized rice husk at a 1 : 1 : 1 ratio, which had been chosen during preliminary tests of the substrates’ composition. Seven days after sowing, 90% of the accessions had emerged, and 30 days after sowing, the seedlings were transplanted to the field. For soil preparation, cleaning and subsequent liming with dolomitic limestone were performed to reach 60% base saturation two months before the establishment of the experiment. Poultry manure was used as a nutrient source at a ratio of 27.5 m3 h−1.
Three months after cultivation, the plants were harvested, and the leaves were placed to dry in an oven with air circulation at a temperature of 40°C for five days.
The extraction of the essential oil from dried leaves was performed by the hydrodistillation method with a Clevenger-type apparatus [
Oil sample analysis was performed on a Shimadzu QP5050A (Shimadzu Corporation, Kyoto, Japan) system comprising a AOC-20i autosampler and gas chromatograph interfaced to a mass spectrometer (GC-MS) instrument employing the following conditions: column J&W Scientific DB-5MS (Folsom, CA, USA) fused silica capillary column (30 m × 0.25 mm i.d. × 0.25
The quantitative analysis of the chemical components was performed by flame ionization detector (FID) gas chromatography using a Shimadzu GC-17A (Shimadzu Corporation, Kyoto, Japan) under the following operating conditions: ZB-5MS capillary column (5% phenyl-arylene-95%-dimethylpolysiloxane) of fused silica (30 m × 0.25 mm i.d. × 0.25
The essential oil components were identified by comparing their mass spectra with spectra available in the database of the equipment (NIST05, NIST21, and WILEY8). These libraries allowed comparisons of the spectral data, which had a similarity index of 80%. Furthermore, the measured retention indices were compared to the indices in the literature [
The chemical composition data were analyzed by two multivariate analysis methods: principal component analysis (PCA) and arrangements analysis (cluster) based on the similarity between individuals and their constituent distribution, using the Statistica software version 7.0 Statsoft company.
The 14 principle compounds were identified from the essential oils of 31 accessions and seven cultivars and are listed according to elution order in Table
Chemical composition of the essential oil of 31 accessions and seven cultivars of basil.
Genotype | Chemical compounds (%) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
C1 | C2 | C3 | C3 | C5 | C6 | C7 | C8 | C9 | C10 | C11 | C12 | C13 | C14 | |
RRI | ||||||||||||||
1033 | 1098 | 1195 | 1228 | 1240 | 1255 | 1270 | 1379 | 1384 | 1401 | 1436 | 1480 | 1513 | 1640 | |
NSL 6421 | 8.76 | 72.15 | 3.00 | 0.00 | 0.00 | 0.51 | 0.00 | 0.00 | 0.00 | 0.00 | 2.37 | 1.12 | 1.02 | 0.00 |
PI 170579 | 8.11 | 38.62 | 0.57 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 30.75 | 0.00 | 0.00 | 0.62 | 1.15 | 5.17 |
PI 170581 | 2.46 | 38.86 | 13.37 | 0.00 | 0.00 | 3.23 | 0.00 | 0.00 | 0.00 | 11.19 | 3.68 | 0.00 | 2.06 | 4.81 |
PI 172996 | 0.00 | 7.28 | 45.82 | 0.00 | 0.00 | 1.79 | 0.00 | 0.00 | 0.00 | 2.72 | 3.79 | 3.58 | 2.73 | 0.00 |
PI 172997 | 0.00 | 9.11 | 28.76 | 0.00 | 0.00 | 0.15 | 0.00 | 0.00 | 0.15 | 8.38 | 0.00 | 10.48 | 2.45 | 14.17 |
PI 174285 | 0.34 | 53.44 | 19.47 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.15 | 0.00 | 3.58 | 2.62 | 2.45 | 5.65 |
PI 176646 | 0.34 | 12.17 | 0.70 | 0.00 | 0.00 | 0.15 | 0.00 | 0.00 | 0.00 | 26.84 | 15.91 | 0.00 | 4.53 | 31.76 |
PI 182246 | 0.34 | 34.15 | 0.70 | 0.00 | 0.00 | 0.15 | 0.00 | 0.00 | 0.00 | 0.10 | 9.91 | 2.62 | 2.45 | 27.35 |
PI 197442 | 8.00 | 61.57 | 0.70 | 0.00 | 0.00 | 19.40 | 0.00 | 0.00 | 0.00 | 0.00 | 2.09 | 2.62 | 2.15 | 1.10 |
PI 207498 | 1.58 | 13.64 | 35.88 | 0.00 | 0.00 | 0.74 | 0.00 | 0.00 | 0.00 | 4.44 | 3.75 | 3.93 | 2.09 | 0.00 |
PI 211586 | 0.00 | 11.27 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 13.52 | 2.62 | 7.99 | 51.22 |
PI 253157 | 0.00 | 19.67 | 21.36 | 6.88 | 4.53 | 6.30 | 0.00 | 0.65 | 0.21 | 1.85 | 3.75 | 2.05 | 0.99 | 0.00 |
PI 296390 | 2.32 | 10.24 | 19.68 | 0.00 | 0.00 | 0.67 | 0.00 | 0.00 | 0.00 | 16.85 | 3.57 | 2.13 | 3.46 | 0.00 |
PI 296391 | 0.00 | 16.54 | 30.78 | 2.71 | 4.87 | 2.63 | 6.30 | 0.00 | 0.00 | 3.55 | 3.03 | 2.74 | 1.68 | 1.29 |
PI 358464 | 10.17 | 70.94 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.92 | 1.26 | 0.69 | 0.00 |
PI 358466 | 0.00 | 17.30 | 3.79 | 1.33 | 0.48 | 46.27 | 0.00 | 1.86 | 0.00 | 1.45 | 4.05 | 1.69 | 1.18 | 0.00 |
PI 358467 | 5.46 | 50.97 | 0.00 | 0.00 | 0.00 | 16.00 | 0.00 | 0.00 | 0.00 | 0.00 | 7.91 | 2.20 | 2.21 | 5.15 |
PI 358471 | 1.31 | 24.58 | 0.00 | 0.00 | 0.00 | 23.46 | 0.00 | 0.00 | 0.00 | 4.29 | 3.27 | 0.85 | 3.56 | 28.41 |
PI 358472 | 0.00 | 59.17 | 0.00 | 0.00 | 0.00 | 20.60 | 0.00 | 0.00 | 0.00 | 0.00 | 9.91 | 2.62 | 2.45 | 5.22 |
PI 368697 | 0.00 | 26.36 | 9.10 | 0.00 | 0.00 | 10.54 | 0.00 | 5.20 | 0.00 | 3.29 | 3.74 | 2.49 | 2.52 | 4.60 |
PI 368698 | 14.19 | 68.65 | 0.00 | 0.00 | 0.00 | 7.57 | 0.00 | 0.00 | 0.00 | 0.00 | 3.75 | 2.62 | 0.00 | 0.00 |
PI 368699 | 0.00 | 24.64 | 0.00 | 0.00 | 0.00 | 17.84 | 0.00 | 0.00 | 0.00 | 5.10 | 13.08 | 5.45 | 2.40 | 20.53 |
PI 368700 | 0.95 | 49.26 | 15.05 | 0.00 | 0.00 | 0.91 | 0.00 | 0.66 | 0.00 | 0.94 | 0.94 | 1.73 | 2.05 | 0.00 |
PI 379414 | 0.34 | 38.22 | 0.70 | 0.24 | 0.00 | 26.78 | 0.00 | 0.00 | 0.00 | 0.00 | 2.90 | 2.62 | 2.45 | 19.38 |
PI 414193 | 5.83 | 44.22 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 9.41 | 2.62 | 5.18 | 32.66 |
PI 414194 | 6.10 | 65.62 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 2.36 | 0.00 | 7.91 | 2.62 | 2.45 | 3.98 |
PI 414196 | 0.34 | 2.93 | 0.70 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 4.06 | 2.62 | 10.68 | 53.60 |
PI 414197 | 7.10 | 44.13 | 5.44 | 0.00 | 0.00 | 0.15 | 0.09 | 0.00 | 0.00 | 0.10 | 5.95 | 2.52 | 2.35 | 29.33 |
PI 414198 | 0.34 | 22.46 | 26.33 | 0.00 | 0.00 | 0.15 | 0.00 | 0.00 | 0.00 | 0.00 | 2.36 | 2.62 | 2.55 | 34.59 |
PI 414199 | 6.66 | 35.98 | 20.70 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 10.91 | 1.62 | 1.45 | 19.83 |
PI 414200 | 1.83 | 38.68 | 14.40 | 0.24 | 0.00 | 0.15 | 0.09 | 0.00 | 0.15 | 0.10 | 2.68 | 2.62 | 2.35 | 17.94 |
Genovese | 11.85 | 75.09 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 3.31 | 0.45 | 0.65 | 1.68 |
Sweet Dani | 0.00 | 0.00 | 0.00 | 5.04 | 33.98 | 1.06 | 43.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Cinnamon | 7.00 | 33.67 | 4.70 | 0.00 | 0.00 | 0.00 | 0.00 | 31.64 | 0.00 | 0.00 | 8.91 | 1.58 | 1.87 | 2.29 |
Fino Verde | 3.30 | 74.84 | 0.00 | 0.00 | 0.00 | 3.45 | 0.00 | 0.00 | 0.00 | 0.00 | 3.20 | 2.62 | 2.25 | 3.50 |
Red Rubin | 13.15 | 65.60 | 0.36 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 5.19 | 0.94 | 0.57 | 1.79 |
Osmin Purple | 0.00 | 63.51 | 0.56 | 0.00 | 0.00 | 0.85 | 0.00 | 0.00 | 3.13 | 0.00 | 0.53 | 3.95 | 0.91 | 2.41 |
Italian Large Leaf | 13.85 | 54.44 | 2.70 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 4.26 | 1.13 | 2.37 | 4.86 |
RRI: Relative Retention Index. Identification of the chemical constituents: C1 = 1,8-cineole, C2 = linalool, C3 = methyl chavicol, C4 = nerol, C5 = neral, C6 = geraniol, C7 = geranial, C8 = methyl cinnamate, C9 =
The cultivar “Cinnamon” stood out for its high concentration of methyl cinnamate, 31%, a chemical constituent with a cinnamon aroma. This constituent was present in only three accessions and always at levels below 6% (Table
The accessions PI 414196, PI 176 646, PI 211586, PI 414193, and PI 414198 showed epi-
The variety “Sweet Dani” contained high levels of neral (33.98%) and geranial (43%) constituents (Table
According to our chemical analyses (Table
Bidimensional dendrogram representing the similarity between 31 accessions and seven cultivars of
Considering the similarities of the chemical constituents of the essential oils of 31 accessions and seven cultivars of basil, the clusters were characterized as follows: Cluster 1 NSL-6421, PI-358 464, “Genovese,” “Fino Verde,” PI-368698, PI-414194, “Red Rubin,” “Osmin Purple,” and “Italian Large Leaf” with linalool and 1,8-cineole as the major compounds; Cluster 2: PI-197442, PI-358472, and PI-358467 with linalool, geraniol, and
Means of the 14 most important chemical constituents of the essential oils of clusters 1 to 8 of
The grouping of cultivars and accessions of basil through the chemical composition of the essential oil provides the market with new groups of plants with similar major active compounds, thus broadening the sources of raw materials for the industries. Various activities of
According to principal component analysis (Figure
Distribution of the chemical constituents of the essential oil of
We observed a correlation greater than 0.50 among some of the chemical constituents of basil essential oil in the accessions and cultivars under study (Table
Correlation coefficients for the most abundant chemical constituents in basil essential oil.
Chemical compound | C2 | C3 | C4 | C5 | C6 | C7 | C8 | C9 | C10 | C11 | C12 | C13 | C14 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
C1 | 0.66 | −0.36 | −0.26 | −0.18 | −0.22 | −0.16 | 0.08 | 0.15 | −0.28 | −0.08 | −0.32 | −0.34 | −0.28 |
C2 | −0.46 | −0.34 | −0.32 | −0.05 | −0.30 | −0.06 | 0.04 | −0.42 | −0.13 | −0.21 | −0.43 | −0.38 | |
C3 | 0.15 | −0.05 | −0.24 | −0.07 | −0.05 | −0.13 | 0.18 | −0.24 | 0.38 | −0.07 | −0.18 | ||
C4 | 0.67 | 0.06 | 0.57 | −0.04 | −0.06 | −0.05 | −0.19 | −0.14 | −0.25 | −0.22 | |||
C5 | −0.07 | 0.99 | −0.04 | −0.04 | −0.07 | −0.22 | −0.21 | −0.23 | −0.16 | ||||
C6 | −0.08 | −0.04 | −0.11 | −0.06 | 0.03 | 0.01 | −0.10 | −0.10 | |||||
C7 | −0.04 | −0.04 | −0.07 | −0.22 | −0.21 | −0.21 | −0.14 | ||||||
C8 | −0.04 | −0.07 | 0.15 | −0.07 | −0.05 | −0.13 | |||||||
C9 | −0.09 | −0.22 | −0.14 | −0.12 | −0.09 | ||||||||
C10 | 0.28 | −0.01 | 0.17 | 0.08 | |||||||||
C11 | −0.06 | 0.38 | 0.48 | ||||||||||
C12 | 0.12 | 0.10 | |||||||||||
C13 | 0.80 | ||||||||||||
C14 | 1.00 |
Identification of the chemical constituents: C1 = 1,8-cineole, C2 = linalool, C3 = methyl chavicol, C4 = nerol, C5 = neral, C6 = geraniol, C7 = geranial, C8 = methyl cinnamate, C9 =
Nerol and neral as well as nerol and geranial, all present in the cultivar “Sweet Dani,” showed a correlation coefficient of 0.67 and 0.57 (moderate), respectively, for each pair. Epi-
Most of the constituents showed correlation coefficients that were classified as weak or very weak, which indicates a low correlation among the variables under study.
The accessions and cultivars were classified according to the chemical composition of their essential oils, forming eight clusters: Cluster 1—mostly linalool and 1,8-cineole; Cluster 2—mostly linalool, geraniol, and
The authors declare that there is no conflict of interests regarding the publication of this paper.
The authors thank ETENE/BNB, CNPq, FAPITEC/SE, and CAPES for their financial support of this work.