Composition and antifungal activity on soil-borne pathogens of the essential oil of Salvia sclarea from Greece

The hydrodistilled essential oils of the aerial parts of wild-growing Salvia sclarea originated from two localities in Greece were analyzed by GC-MS. Sixty-six compounds, representing 93.26-98.19% of the oils, were identified. Linalyl acetate (19.75-31.05%), linalool (18.46-30.43%), geranyl acetate (4.45-12.1%), and alpha-terpineol (5.08-7.56%) were the main components. The antifungal activity of the oil of one locality and of the main components, linalyl acetate and linalool, was evaluated in vitro against three soil-borne pathogens.     

Volatile Compounds and Antioxidative Activity of <Emphasis Type="Italic">Porophyllum tagetoides</Emphasis> Extracts

Porophyllum tagetoides is an annual warm-weather herb that has an intense typical smell. Its leaves are commonly used in soup preparation and traditional medicine for treatment of inflammatory diseases. Its volatile compounds and antioxidant properties were evaluated in crude, aqueous and ethanol leaf extract and an oil emulsion using different antioxidant assays in vitro, such as: DPPH radical scavenging activity, redox potential, polyphenol content, reducing power and optical density. A high antioxidative activity was found when comparing leaves with stems. The crude extract from leaves showed a very high reducing power (2.88 ± 0.20 O.D.) and DPPH radical-scavenging activity (54.63 ± 4.80%), in concordance with a major concentration of vitamin C (23.97 ± 0.36 mg/100 g). Instead, the highest polyphenol content (264.54 ± 2.17 mg GAE/g of sample) and redox potential (561.23 ± 0.15 mV) were found by the ethanol and aqueous extract, respectively. Aldehydes and terpenes such as nonanal, decanal, trans-pineno, β-myrcene and D-limonene were the major volatiles found. This study suggests that Porophyllum tagetoides extracts could be used as antioxidants.     

Characterisation of Nanoestructured Potato Starch Powders with Blackberry (<Emphasis Type="Italic">Rubus fruticosus</Emphasis> Var. Brazos) Juice

Potato starch has been used in the protection of antioxidants, but its use is limited due to its physicochemical properties. The objective of this work was to evaluate the effect of physical modification of potato starch by gelatinization, spray-freezing on liquid nitrogen and freezing in liquid nitrogen on the physicochemical properties and stability of powders added with blackberry juice. Frozen potato starch with liquid nitrogen exhibited higher colour retention and anthocyanins during processing, as well as adequate physicochemical and flow properties. While the spray-frozen starch on liquid nitrogen had a higher retention of anthocyanins, polyphenols and antioxidant activity during storage under controlled conditions. Atomic force microscopy revealed the modification in the microstructure of the developed powders. These results demonstrated that the microstructure of the powders was modified by conferring changes in the water adsorption capacity affecting their physicochemical properties and their stability during storage.     

Sex matters: Modeling male and female habitat differences for jaguar conservation

Competition for mates, cub rearing, and other behaviors differ between males and females in large carnivores. Although these differences can be reflected in patterns of habitat use, gender has rarely been incorporated into habitat models. We evaluated differences in habitat use between male and female jaguars in the Mayan Forest of the Yucatan Peninsula by modeling occupancy as a function of land cover type, distance to roads, and sex. Nested models were fitted to high-spatiotemporal resolution satellite (GPS) telemetry, controlled for temporal autocorrelation, and eliminated selection bias of pseudo-absences using a semi-non-parametric bootstrap. Although both male and female jaguars prefer tall forest, short forest was also preferred by females but avoided by males. Whereas females significantly avoided roads, males didn’t and ventured into low-intensity cattle ranching and agriculture. Females’ preference for intact forests and against roads led to their habitat being fragmented to a greater degree than that of males. Models that ignored sexual differences failed to capture the effect of roads and agriculture on jaguar habitat use, blurred the distinction of use between short and tall forest, and underestimated fragmentation of female jaguar habitat; but incorporating these differences increased precision of habitat maps and allowed the identification of potential jaguar-human conflict areas associated with male’s use of cattle and agricultural lands. Specifying sex differences increases the power of habitat models to understand landscape occupancy by large carnivores, and so greater attention should be paid to these differences in their modeling and conservation.     

Volatile metabolites from Salvia fruticosa as antifungal agents in soilborne pathogens

The volatile metabolites of Salvia fruticosa plants, growing wild in 15 localities scattered across Greece, were analyzed by means of GC and GC-MS. The essential oil content ranged from 0.69 to 4.68%, and the results of the analyses showed a noticeable variation in the amounts of the five main components [1,8-cineole, alpha-thujone, beta-thujone, camphor, and (E)-caryophyllene]. The antifungal activities of the essential oils from two localities, belonging in two different groups of cluster and principal component analysis, and their main components (1,8-cineole and camphor) were evaluated in vitro against five phytopathogenic fungi. Both oils were slightly effective against Fusarium oxysporum f. sp. dianthi and Fusarium proliferatum, whereas against Rhizoctonia solani, Sclerotinia sclerotiorum, and Fusarium solani f. sp. cucurbitae the oils exhibited high antifungal activities.     

The effect of light intensity on the concentration of bioelements in the sap of the tomato plant (Lycopersicon esculentum L.)

The subject of the study was the effect of light intensity on the concentration of bioelements in the sap of the tomato plant (Lycopersicon esculentum L.), cultivated hydroponically with a normal nutrient solution. The greenhouse experiment took place under controlled parameters.

The results show that the concentration of bioelements in the sap varies least during the first two hours of light. It is also interesting to note that the interval between the fourth and sixth hour offers possibilities for the study of the content of reducing sugars in the sap.     

Effect of balanced solutions with different osmotic pressure on tomato plant

A study has been made of the effect of osmotic pressures (O.P.), 0.6, 2.0, 3.5 and 5.0 atm. produced by balanced nutritional solutions in tomato plants. With the maximum O.P. there is a 40% decrease, approximately, in the fresh weight. The increas ed O.P. also produces a decrease in the water content of the plant and an increase in the cation and anion content, not maintaining the ratios between ions, which produces an unbalance in the metabolism in order to increase the concentration of compounds which raise the internal O.P. of the plant.     

Variations in the composition of the sap of zea mays with the increase in osmotic pressure of the nutritive solution

The alterations are studied which are produced in the content of mineral elements and organic fractions of sap with the increase in the osmotic pressure of the nutritive solution at levels of 2.0; 3.5 and 5.0 atm., obtained through the addition to the nutritive solution either of magnesium sulphate or PEG‐4000.

Through the effect of the osmotic pressure, the transformations are modified of the nitrogen and mineral phosphorus at organic fractions experience a series of modifications which produce different values in the Nm%TSN and Pm%TSP ratios with respect to control. Through action of the specific effect of magnesium sulphate, the reducing sugars concentrations in sap having an important increase.