Intraspecific variation in essential oil composition of the medicinal plant Lippia integrifolia (Verbenaceae). Evidence for five chemotypes.

The aerial parts of Lippia integrifolia (incayuyo) are widely used in northwestern and central Argentina for their medicinal and aromatic properties. The essential oil composition of thirty-one wild populations of L. integrifolia covering most of its natural range was analyzed by GC and GC-MS. A total of one hundred and fifty two terpenoids were identified in the essential oils. Sesquiterpenoids were the dominant components in all but one of the collections analyzed, the only exception being a sample collected in San Juan province where monoterpenoids amounted to 51%. Five clearly defined chemotypes were observed. One possessed an exquisite and delicate sweet aroma with trans-davanone as dominant component (usually above 80%). Another with an exotic floral odour was rich in oxygenated sesquiterpenoids based on the rare lippifoliane and africanane skeletons. The trans-davanone chemotype is the first report of an essential oil containing that sesquiterpene ketone as the main constituent. The absolute configuration of trans-davanone from L. integrifolia was established as 6S, 7S, 10S, the enantiomer of trans-davanone from 'davana oil' (Artemisia pallens). Wild plants belonging to trans-davanone and lippifolienone chemotypes were propagated and cultivated in the same parcel of land in Santa Maria, Catamarca. The essential oil compositions of the cultivated plants were essentially identical to the original plants in the wild, indicating that the essential oil composition is largely under genetic control. Specimens collected near the Bolivian border that initially were identified as L. boliviana Rusby yielded an essential oil practically identical to the trans-davanone chemotype of L. integrifolia supporting the recent view that L. integrifolia (Gris.) Hieron. and L. boliviana Rusby are synonymous.

Composition, in vitro antioxidant and antimicrobial activities of essential oil and oleoresins obtained from black cumin seeds (Nigella sativa L.).

Gas chromatography-mass spectrometry (GC-MS) analysis revealed the major components in black cumin essential oils which were thymoquinone (37.6%) followed by p-cymene (31.2%), α-thujene (5.6%), thymohydroquinone (3.4%), and longifolene (2.0%), whereas the oleoresins extracted in different solvents contain linoleic acid as a major component. The antioxidant activity of essential oil and oleoresins was evaluated against linseed oil system at 200 ppm concentration by peroxide value, thiobarbituric acid value, ferric thiocyanate, ferrous ion chelating activity, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging methods. The essential oil and ethyl acetate oleoresin were found to be better than synthetic antioxidants. The total phenol contents (gallic acid equivalents, mg GAE per g) in black cumin essential oil, ethyl acetate, ethanol, and n-hexane oleoresins were calculated as 11.47 ± 0.05, 10.88 ± 0.9, 9.68 ± 0.06, and 8.33 ± 0.01, respectively, by Folin-Ciocalteau method. The essential oil showed up to 90% zone inhibition against Fusarium moniliforme in inverted petri plate method. Using agar well diffusion method for evaluating antibacterial activity, the essential oil was found to be highly effective against Gram-positive bacteria.

Northwestern Argentina: a center of genetic diversity of lemon verbena (Aloysia citriodora PALÁU, Verbenaceae).

The aerial parts of lemon verbena (Aloysia citriodora PALÁU) are worldwide used due to their medicinal and aromatic properties. The essential-oil and acteoside contents have been proposed as the main quality markers for their pharmacological and organoleptic features. The northwestern region of Argentina has been repeatedly proposed as the place of origin for this species. For this reason, the essential-oil yields and chemical compositions of leaves of 25 populations of lemon verbena from both wild collections and experimental crops from this region were studied. Plants from six different collections were subsequently grown on the same experimental parcel located at Cerrillos, Salta province, during more than seven years. In addition, the acteoside contents determined in all the samples collected in 2010 showed significant variations (from 0.5 to 4.0%). Large differences were observed in the essential-oil composition and yields, which ranged from 0.4 to 2.1% (v/w). Nevertheless, most of the samples complied with the European Pharmacopoeia specifications. A remarkable chemical diversity with at least four clearly defined chemotypes was detected in this region. Therefore, it would be urgent to encourage actions to protect these genotypes of lemon verbena in the northwestern Argentina.

Antioxidant, hemolytic and cytotoxic activities of Senecio species used in traditional medicine of northwestern Argentina.

Senecio nutans Sch. Bip., S. viridis var. viridis Phill. and S. spegazzinii Cabrera are native species used in traditional medicine of northwestern Argentina. The total phenolics, flavonoids and caffeoylquinic acids contents, as well as radical scavenging, antioxidant, hemolytic and cytotoxic activities of aqueous extracts (infusion and decoction) of all three species were determined. S. nutans was the most active. The extracts did not show antibacterial activity. Alkaloids were not detected in any of the aqueous extracts of the three studied species.

Chemistry and antioxidant activity of essential oil and oleoresins of black caraway (Carum bulbocastanum) fruits: Part 69.

BACKGROUND: The present study describes the chemical analysis of the essential oil and oleoresins from caraway, which have been studied by using GC-MS. The paper also explains the importance of the extracted oil and oleoresins in the antioxidant activities of target plant species. RESULTS: GC-MS analysis of caraway essential oil showed 51 compounds representing about 96.6% of the total weight. The major components were dillapiole (44.6%), germacrene-beta (14.1%), nothoapiole (8.3%), and beta-selinene (6.8%), along with many other components in minor amounts. Major components in ethyl acetate and iso-octane oleoresins are dillapiole, nothoapiole and germacrene-beta, whereas in ethanol oleoresin contains dillapiole (25%), sitosterol (21.3%) stigmasterol (9.5%) and nothoapiole (8.1%). The antioxidant activity was evaluated by various antioxidant assays such as peroxide, thiobarbituric acid and p-anisidine values. These experiments were further supported by other complementary antioxidant assays such as ferric thiocyanate method in linoleic acid system, reducing power, and scavenging effects on 1,1'-diphenyl-2-picrylhydrazyl (DPPH). Both the caraway volatile oil and its oleoresins showed strong antioxidant activity in comparison with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). CONCLUSION: This study provides additional information about the chemistry and antioxidant activity of caraway. Hence, caraway may be used as natural food preservatives.

Comparative study of chemical composition and antioxidant activity of fresh and dry rhizomes of turmeric (Curcuma longa Linn.).

The phytoconstituents of essential oil and ethanol oleoresin of fresh and dry rhizomes of turmeric (Curcuma longa Linn.) were analyzed by GC-MS. The major constituents were aromatic-turmerone (24.4%), alpha-turmerone (20.5%) and beta-turmerone (11.1%) in fresh rhizome and aromatic-turmerone (21.4%), alpha-santalene (7.2%) and aromatic-curcumene (6.6%) in dry rhizome oil. Whereas, in oleoresins, the major components were alpha-turmerone (53.4%), beta-turmerone (18.1%) and aromatic-turmerone (6.2%) in fresh and aromatic-turmerone (9.6%), alpha-santalene (7.8%) and alpha-turmerone (6.5%) in dry rhizome. Results showed that alpha-turmerone, a major component in fresh rhizomes is only minor one in dry rhizomes. Also, the content of beta-turmerone in dry rhizomes is less than a half amount found in fresh rhizomes. The antioxidant properties have been assessed by various lipid peroxidation assays as well as DPPH radical scavenging and metal chelating methods. The essential oil and ethanol oleoresin of fresh rhizomes have higher antioxidant properties as compared dry ones.

Chemistry, antioxidant and antimicrobial investigations on essential oil and oleoresins of Zingiber officinale.

The essential oil and oleoresins (ethanol, methanol, CCl(4) and isooctane) of Zingiber officinale were extracted respectively by hydrodistillation and Soxhlet methods and subjected to GC-MS analysis. Geranial (25.9%) was the major component in essential oil; eugenol (49.8%) in ethanol oleoresin, while in the other three oleoresins, zingerone was the major component (33.6%, 33.3% and 30.5% for, methanol, CCl(4) and isooctane oleoresins, respectively). The antioxidant activity of essential oil and oleoresins were evaluated against mustard oil by peroxide, anisidine, thiobarbituric acid (TBA), ferric thiocyanate (FTC) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging methods. They were found to be better antioxidants than butylated hydroxyanisole (BHA). The antimicrobial properties were also studied using various food-borne pathogenic fungal and bacterial species. The essential oil and CCl(4) oleoresin showed 100% zone inhibition against Fusarium moniliforme. For other tested fungi and bacteriae, the essential oil and all oleoresins showed good to moderate inhibitory effects. Though, both essential oil and oleoresins were found to be effective, essential oil was found to be better than the oleoresins.

Evaluation of chemical and antiviral properties of essential oils from South American plants.

The essential oils of seven aromatic plants from Córdoba, San Luis and San Juan Provinces (Argentina) were isolated by steam distillation and analysed by a gas chromatography/mass spectrometry technique. The oils were screened for cytotoxicity and in vitro inhibitory activity against herpes simplex virus type 1 (HSV-1), dengue virus type 2 (DENV-2) and Junin virus (JUNV) by a virucidal test. The oils showed a variable virucidal action according to the virus. The better relationship between cytotoxicity and antivirus action was observed with the essential oils of Heterothalamus alienus and Buddleja cordobensis against JUNV, with virucidal concentration 50% (VC50) values of 44.2 and 39.0 ppm and therapeutic indices (cytotoxicity to virucidal activity ratio) of 3.3 and 4.0, respectively. The inhibitory action was exerted by a direct interaction of virions with the oils. Virions inactivated with B. cordobensis and H. alienus essential oil were not affected in their ability to bind to the host cell. The therapeutic indices shown by these essential oils in toto were very modest, but given the complexity of their chemical composition the future identification of the precise active principle may allow the elimination of cytotoxic components and increase the selectivity of the effective compound.