Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The concentration of seventeen mineral elements was analyzed in 130 commercial samples of Chilean wines, using flame atomic absorption spectroscopy and inductively coupled plasma–mass spectrometry. The elements analyzed were within the usual concentration ranges previously reported in other wine regions; for instance: Fe, 2.08±0.99 mg L-1; Zn, 0.71±0.44 mg L-1; K, 788.10±219.66 mg L-1; Na, 14.62±8.61 mg L-1. When the mineral content of the samples was compared among wine areas, significant differences in the concentration of K, Na, Mn, Mg, Zn, and Cr were observed (p ≤ 0.05). Moreover, principal component and linear discriminant analyses were used to discriminate wines according to provenance, obtaining adjustments above 90 % for white wines and over 70 % for red wines.

Mechanized operations on soils with inadequate moisture cause compaction and are deleterious to soil quality. The aim of this study was to evaluate the influence of different oilseed crop successions on the structural quality of a clayey Rhodic Hapludox. Sunflower (Helianthus annuus L.), canola (Brassica napus L. and Brassica rapa), safflower (Carthamus tinctorius L.), crambe (Crambe abyssinica Hochst.), and niger (Guizotia abyssinica) were sown in autumn/winter in a no-tillage system in succession to corn grown in the summer and soybean/corn grown in summer/autumn-winter. When the autumn-winter crops began to grow, soil samples were collected in metallic cylinders at 0.0–0.05 m and 0.05–0.10 m depths. Analyses of the optimal water interval in each crop succession at the 0.0–0.05 m layer indicated that the corn/safflower and corn/crambe successions reduced the structural quality of the soil. The autumn-winter niger crop in succession to summer corn improved the soil structure at 0.0–0.05 m and 0.05–0.10 m when compared with the soil cultivated with the soybean/corn succession. The niger crop is an effective crop rotation alternative that improves the physical quality of the soil under no-tillage systems.

Canes obtained from one-year-old stems of the grapevine cultivars Cabernet Franc,Malbec, Merlot, Sauvignon Blanc and Syrah (all non-grafted) were used as models to test their susceptibility to Diplodia seriata and Diplodia mutila. The results showed that the mean length of lesions caused by D. mutila was 3.2 times larger than that produced by D. seriata. In addition, the Cabernet Franc and Syrah cultivars were the most susceptible to D. mutila, while Merlot and Malbec were the least susceptible. No significant differences were observed between cultivars inoculated with D. seriata. The results are discussed in terms of the susceptibility of the different grapevine cultivars to both pathogens. 

Nothofagus pumilio (lenga) is the most important native species for timber production in southern Patagonia both in Chile and Argentina. Thinning application to second-growth N. pumilio forests has been limited in Patagonia, probably because of the long time necessary for the investment to be recovered. In addition, experimental trials have focused mostly on thinnings from below, leaving a high residual stand density, which has led to a modest growth response. Using measurements (1995–2014) obtained from a thinning trial carried out in a second-growth N. pumilio forest located in Tierra del Fuego (Chile), the objective of this case study was to analyze whether selective thinnings with future crop trees (in the sense of Z-Bäumen thinning) promote greater growth responses than those from a thinning from below. In addition, we explored the associations between climatic factors and age on N. pumilio tree growth. Trial treatments comprised a control, a thinning from below and a future crop tree thinning. The growth response after a future crop tree thinning was greater and lasted for a longer period (10 yrs) than did the thinning from below (4 yrs). The tree basal area and diameter at breast height (dbh) growth increased with dbh and annual absolute minimum temperature and decreased with age for the unthinned treatment during the period from 1977–2014 (~70–110 yrs old). Our results suggest that the future crop thinning might be a better alternative than the thinning from below for secondary N. pumilio forests in Patagonia due to the greater growth response while being a less intensive silvicultural method. 

Treating wines with cation exchange resins allows the reduction of pH and contributes to limiting the formation of tartrate salts by exchanging cations such as potassium with hydrogen ions. This manuscript summarizes the results of a series of laboratory and winery-scale trials performed with the aim of evaluating the ion exchange process and its effects on the chemical composition of the treated samples. The laboratory-scale results showed that both the procedure employed for the activation of resins and the chemical composition of the wines affected the extent of the chemical changes occurring during the treatment. As such, the winery-scale trials showed that the resin-treated wines have significantly lower pH, higher total acidity, less tartrate formation (measured by weight), and a reduced amount of most metals analyzed. Wine samples blended with approximately 20% of cation exchange-treated samples (by volume) showed no signs of tartrate instability when assessed by a quick qualitative cold test.

The aim of this work was to determine the antioxidant activity, total phenolic content (TPC) and total flavonoid content (TFC) in the rhizomes and stems of Jatropha dioica and their relation to collection season, collection location, extraction solvent and their interactions to understand the effect of climate conditions on the synthesis of the antioxidant compounds in J. dioica. Plants were collected during different seasons at two locations in Mexico. A 3-factorial experimental design was used for the stems and rhizomes, using the extraction solvent, collection location and season as sources of variation. A Tukey’s test with a P≤0.05 significance level was used to perform the comparison of the means. Significant differences were found when comparing the three sources of variation separately for TPC and antioxidant activity in the stems and rhizomes. In terms of the interactions for the stems, there was a significant difference between the Morelos × 70% ethanol × dry interaction and Tetepango × water × rain interaction for the TPC and the antioxidant activity; however, no significant difference was found for the TFC. In terms of the rhizomes, a significant difference was found among the 4 variables analyzed. These results indicate that collection location, collection season and extraction solvent affect the TPC and antioxidant activity. In addition, the rhizomes presented higher antioxidant activity and TPC than that of the stems.

In this study, we researched the chemical composition and the antifungal and antibacterial activity of volatile oil from Mentha spicata. The Gas chromatography/mass spectrometry (GC/MS) analysis of M. spicata showed that the main component was carvone (56.94%), followed by limonene (11.63%), sabinene hydrate (7.04%) and caryophyllene (4.06%). The antifungal activity of the volatile oil from M. spicata L. was determined with respect to plant pathogenic fungi, such as Fusarium oxysporum f. sp. radicis-lycopersici (Sacc.) W.C. Synder & H.N. Hans (FORL), Rhizoctonia solani J.G. Kühn. (R. solani), Alternaria solani (A. solani), and Verticillium dahliae Kleb (V. dahliae). The volatile oil was shown to have strong antifungal activity against plant pathogenic fungi. The result of the study was that at a dose of 12 μL petri-1, the volatile oil inhibited 100% of mycelium growth in V. dahliae, A. solani FORL and R. solani. Volatile oil exhibited remarkable activity against the selected bacterial strains of Xanthomonas spp. (ZI365, ZI366, ZI368, ZI370, ZI373, ZI375, ZI376, ZI378).

Fire produces changes in vegetation, soil, fauna, and water quality, and it can even modify atmospheric chemical composition. Changes in soil fertility, microorganisms and vegetation were evaluated after a fire in two municipalities in the State of Hidalgo, Mexico. Inside and outside the burned area, four 100 m2 plots were established. In each of the eight plots, soil samples were collected at two depths (0–5 and 5–20 cm) in the following areas: non-burned area (NBA); 15 days after fire (15DAF); and 12 and 24 months after the fire (MAF). Vegetation quantification was carried out at 30, 180 and 540 DAF. The results at 15DAF showed an increase of alkaline and metallic elements as well as pH in the surface layer, and this trend remained the same to 12MAF. There was greater Fe, Mn and Zn content in Zacualtipán and greater K, Ca, Mg and P in Singuilucan. At 24MAF, due to the nutrient requirements of the herbaceous and scrub growth, this effect was reverted. The fire reduced the organic matter (OM) and total nitrogen (TN) contents, without any recovery during the evaluated period. Bacteria showed greater mortality because of the fire: 76% and 50% at the Zacualtipán and Singuilucan sites, respectively. The canopy opening promoted a 50% increase of species in Zacualtipán. In conclusion, the fire temporarily increased soil fertility and the presence of herbaceous vegetation, but it reduced the bacteria and fungi populations.

In recent years, Chile has been the Chinese market’s main supplier of fresh sweet cherries. The aim of this study was to develop a relational model with two working hypotheses to model Chinese consumer satisfaction with sweet cherries as a result of the quality perceived by intrinsic and extrinsic attributes. One hundred and ninety-three buyers in the Sanyuanli Market in the Chaoyang District, Beijing, were surveyed using closed-ended questions on a Likert scale. To develop a model that fulfilled the indicated objective, an exploratory factor analysis and a subsequent system of structural equations were used to confirm the relationships, presenting an adequate goodness-of-fit test to accept the model according to the literature. Among the main results, it was determined that consumer satisfaction with sweet cherries is explained by the perceived intrinsic quality, where medium size and color are the determining attributes, and the product price, Chilean origin and delivery time explain the perceived extrinsic quality (critical ratio of 2.937 and p-value of 0.003). Finally, the intrinsic quality positively and significantly influences Chinese consumer satisfaction with sweet cherries, in contrast to the results for perceived extrinsic quality, which are not statistically significant.

The present study aimed to examine the effects of solid-state fermentation (SSF) using selective A. niger strains on the amino acid, mineral, condensed tannin, and other chemical contents of olive leaves. The dried samples were divided into nonfermented (C) and fermented (F) olive leaves, and the latter were fermented by the following A. niger strains: ATCC® 9142TM (F1), ATCC® 200345TM (F2), ATCC® 52172TM (F3), and ATCC® 201572TM (F4), with three replicates for each treatment. Group F4 presented the best results, although all fermented groups generally presented higher performance than C. The total content of amino acids of the fermented olive leaves increased by 68–209% in comparison to that of C, while the cellulose content of the fermented olive leaves decreased by 7–25%. The ash, crude protein (CP), and ether extract (EE) contents increased after fermentation, but the crude fiber (CF) and nitrogen-free extract (NFE) contents decreased. The content of neutral detergent fiber (NDF) did not change, but acid detergent fiber (ADF) varied among the groups. The starch and sugar contents of all fermented groups except F1 also decreased compared to those of C. The mineral contents increased in all fermented groups, and the condensed tannin content varied according to the A. niger strain used. Thus, olive leaves fermented with different A. niger strains, especially F4, seem to have considerable potential as ruminant feed, as they are enriched with amino acids and minerals and have an improved chemical composition. However, these results should be supported and validated by animal experiments.