Phytochemical and Biological Profile of Essential Oils of Elionurus muticus (Spreng.) Growing in Northeastern Argentina.

The purpose of this study was to investigate essential oils (EOs) from leaves of Elionurus muticus growing in Northeastern Argentina regarding their physicochemical profiles as well as their biological potential. Roots of a selected E. muticus population were investigated too. For this purpose, EOs of fresh materials were obtained by steam distillation and the chemical composition was characterized by gas chromatography GC/MS-FID. Antibacterial, antioxidant and eco-toxicity activities of the essential oils (EOs) were tested by in vitro assays. The EOs showed three E. muticus chemotypes: citral (neral+geranial), acorenone+bisabolone, acorenone+geranial. EO of roots of citral population contains mainly acorenone derivatives. EOs have high antibacterial effect against Staphylococcus aureus, being found minor antibacterial effect against Gram-negative bacteria. The half-maximal inhibitory concentration of EOs against DPPH⋅ were 7.1-30.0 mg/mL and the eco-toxicity was high with LD50 <39 µg/mL. Based on the findings, given the high variability in their chemical composition and biological activity of E. muticus EO and the promising yields, it could be potentially chosen for industrial applications.

Bioactive phenolic compounds and organic acids in the decoction of fruits and leaves of Schinus areira L / Compuestos fenólicos bioactivos y ácidos orgánicos en la decocción de frutos y hojas de Schinus areira L

Leaf and fruit decoctions of Schinus areira L. from northwest Argentina were investigated here. Phenolic compounds and organic acids were analyzed by HPLC. Antioxidant capacity and α-glucosidase inhibition were determined by using in vitro tests. The general toxicity was assessed against Artemia salina nauplii. Hyperoside and 3 O-caffeoylquinic acid in leaf decoctions; gallic acid and catechin in fruit decoction were the major phenolic compounds. Malic and citric acids were the main organic acid quantified in the leaf and fruit decoctions, respectively. Fruit decoction had a relatively important content of shikimic acid, precursor of Tamiflu. Leaf decoction presents a greater richness in bioactive compounds with antiradical activity against DPPH●, O2●-and ●NO radicals. S. areira leaves and fruits had α-glucosidase inhibitory activity comparable to hyperoside and acarbose. Fruit decoction was not eco-toxic; leaf decoction showed significant eco-toxic activity and could be chosen for the search of other bioactive compounds with pharmacological activity.

Se investigaron decocciones de hojas y frutos de Schinus areira L. del noroeste de Argentina. Compuestos fenólicos y ácidos orgánicos se analizaron mediante HPLC. Capacidad antioxidante e inhibición de α-glucosidasa se determinaron in vitro. Se evaluó toxicidad general con Artemia salina. Los principales compuestos fenólicos fueron hiperósido y ácido 3 O-cafeoilquínico en hojas y ácido gálico y catequina en frutos. Los principales ácidos orgánicos cuantificados fueron málico en hojas y cítrico en frutos. Ácido shikímico, precursor del Tamiflu está presente en decocción de frutos con un contenido relativamente importante. La de hojas presenta una mayor riqueza en compuestos bioactivos con actividad antirradicalaria frente a DPPH●, O2●-y ●NO. Las hojas y frutos de S. areira tenían una actividad inhibidora de la α-glucosidasa comparable a la de hiperósido y acarbosa. La decocción de frutas no fue eco-tóxica, pero sí la de hojas que podría ser fuente de compuestos bioactivos con actividad farmacológica.

Optimized formulation of a Physalis peruviana L. fruit nectar: physicochemical characterization, sensorial traits and antioxidant properties.

The aim of this research was to develop and characterize an innovative nectar formulation of Physalis peruviana fruits from the Argentinean Northern Andean region with optimized proportions of pulp and sucrose that maximizes the antioxidant activity and with good sensorial acceptance, using the response surface methodology as optimization strategy. Physicochemical characteristics (total soluble solids, titratable acidity and pH), antioxidant activity (measured as the free radical scavenging activity against DPPH·) and sensorial attributes (color, acidity, sweetness, texture, aroma and overall acceptance) were evaluated in a series of nectar formulations. A significant correlation between overall acceptance and antioxidant activity contributed to achieve the objective outlined. The mathematical modelling defined a nectar with 65% fruit juice and pulp and 8% sucrose; this nectar presented absence of indicator microorganisms (aerobic mesophilic microorganisms, molds and yeasts, Salmonella spp., total coliforms, and Staphylococcus aureus coagulase positive) despite having no added preservatives. ß-carotene and vitamin C contents (1.13 ± 0.02 and 16.56 ± 0.52 mg/100 mL respectively) and antioxidant activity towards DPPH· (EC50: 2.43 ± 0.07 mg/mL), ABTS·+ (3.48 ± 0.07 µmol Trolox/mL) and FRAP (10.16 ± 0.10 µmol Trolox/mL), make this nectar a functional food with potential for the food industry.

Nutritional and Antioxidant Properties of Physalis peruviana L. Fruits from the Argentinean Northern Andean Region.

Physalis peruviana L. fruits have gained great interest in different producing countries because they are good source of nutrients and bioactive compounds. However, the nutritional characterization and bioactive properties of both cultivated and wild fruits of P. peruviana growing in Argentina have not been conducted so far. The results provided clear difference in physicochemical, nutritional and bioactive characteristics of cultivated and wild fruits of P. peruviana from Argentinean Northern Andean region. Cultivated fruits showed a higher content of K, Mg and Cu and bioactive compounds as vitamin C than wild fruits. Besides, cultivated fruits displayed a high antiradical activity towards ABTS●+ and FRAP. In addition, both cultivated and wild fruits exhibited a great antioxidant activity measured as the free radical scavenging activity against DPPH● (effective concentration that scavenged 50% of the radicals is 0.64 and 1.65 mg/mL, respectively). The findings point out that the nutritional properties and bioactive compounds (vitamin C and ß-carotene) of cultivated and wild fruits were comparable to those from countries with a production tradition. Outstandingly, the antioxidant performance of fruits growing in Argentinean Northern Andean region is remarkable in comparison with those reported in other producing zones, which can be ascribed to suitable ecological conditions.

Chemical Composition and Biological Prospects of Essential Oils and Extracts of Aphyllocladus spartioides Growing in Northwest Argentina.

Aphyllocladus spartioides Wedd. is a native and aromatic herb used in traditional medicine, however it is still poorly investigated. In this work, the volatile profile of A. spartioides growing in Hornillos-Northwest Argentina was determined by GC/MS/FID and the phenolic compounds of hydroethanolic and decoction extracts were analyzed by HPLC-DAD. The antibacterial potential, antioxidant activity and α-glucosidase inhibition activity were checked by in vitro assays. The volatile profile allowed the identification of 68 compounds, being α-pinene and cadinene the main ones. Eighteen phenolics were identified, isorhamnetin derivatives and different phenolic acid derivatives were found in higher amounts, mainly in the hydroethanolic extract. A concentration-dependent activity was noticed against DPPH· , O2·-, ·NO and α-glucosidase, these activities being reported for the first time. Hydroethanolic extract was most active against DPPH· , · NO and α-glucosidase (IC50 = 79, 206 and 181 µg/ml). Decoction extract proved to be better against O2·- (IC50 = 20 µg/ml). Regarding the antibacterial activity, hydroethanolic extract was more active compared with decoction and essential oil. MICs of 0.3 - 0.6 mg/ml were obtained against Staphylococcus aureus, Bacillus cereus, and Micrococcus luteus. Results suggest that the extracts of A. spartioides from Northwest Argentina may be interesting to use as a source of natural antioxidants/antimicrobials for pharmaceutical incorporations or food supplementation.

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.

The inhibition of methicillin-resistant Staphylococcus aureus by essential oils isolated from leaves and fruits of Schinus areira depending on their chemical compositions.

Schinus areira L. is a native plant from South America used for centuries in traditional medicine. Here, we investigate the antimicrobial activity of four essential oils extracted from leaves and fruits of S. areira exhibiting different chemical profiles. The antibacterial activity against the human pathogenic bacteria Staphylococcus aureus susceptible as well as methicillin resistant strain was assessed by the broth microdilution assay. The results showed that the limonene-rich oil extracted from the leaves and fruits have potent antibacterial effect on S. aureus ATCC 25923, while the α-phellandrene-rich fruit oil having a lower content of limonene showed the lowest antibacterial efficacy. In this work, for the first time, we demonstrated the bactericidal activity of essential oils isolated from fruits and leaves of S. areira against susceptible and methicillin resistant S. aureus strains. All results point out the potential use of the S. areira oils as antimicrobial agents to be used, at least against Staphylococcal infections.

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.

Influencia de la temperatura sobre la biodegradación de polietileno

Se estudió la influencia de la temperatura sobre la biodegradación de polietileno de alta y baja densidad, con microorganismos de lombricompost. Los resultados obtenidos permitiran definir, para cada una de los plásticos estudiados, la mejor temperatura de trabajo a aplicar en un tratamiento a escala real de los mismos

Influencia de la temperatura sobre la biodegradación de polietileno

Se estudió la influencia de la temperatura sobre la biodegradación de polietileno de alta y baja densidad, con microorganismos de lombricompost. Los resultados obtenidos permitiran definir, para cada una de los plásticos estudiados, la mejor temperatura de trabajo a aplicar en un tratamiento a escala real de los mismos

Biodegradación de polipropileno: evaluación gravimétrica y por espectroscopía infrarroja

Considerando las importantes cantidades de residuos de polipropileno y con el fin de conocer si objetos de este plástico pueden ser biodegradados, a qué velocidad y con qué mecanismo, se estudia la evolución de la pérdida de peso, durante 14 meses, de trozos de bandejas de polipropileno, enterradas en humus de lombricultura, a 25ºC y 40-50 porciento de humedad, analizándose, además, al final de los ensayos, los espectros infrarrojo de muestra y testigo. Se verificó la biodegradación del plástico estudiado por gravimentría y por espectrofotometría, y se encontró que la degradación ocurre por ruptura de las uniones del carbono metínico del polipropileno

5-methylcoumaranones from Mutisia friesiana and their bioactivity.

In addition to the known mutisicoumaranones A (1) and B (2), the methanolic extract of the aerial parts of the shrub Mutisia friesiana afforded two new 5-methylcoumaranones, mutisicoumaranones C (3) and D (4). Their structures were elucidated by spectroscopic methods. (13)C NMR data for mutisicoumaranones A and B are reported for the first time. All compounds showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum and bactericidal activity against Staphylococcus aureus. The presence of 5-methylcoumaranones A-D is biosynthetically related to 5-methylcoumarins and phenolic derivatives previously isolated from M. friesiana.

Antifungal methylphenone derivatives and 5-methylcoumarins from Mutisia friesiana.

In addition to the known mutisicoumarin A, the aerial parts of the shrub Mutisia friesiana afforded five new methylphenones, two new 5-methylcoumarins and a new related chromone. Their structures were elucidated by spectroscopic methods 13C NMR data for mutisicoumarin A are reported for the first time. Mutisiphenones A and B and mutisicoumarin A showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum.