Ziziphus Mistol Research Articles

In Vitro Hypoglycemic and Anti-Inflammatory Potential and Toxicity of Powders from Pulp and by-Products of Ziziphus mistol from Argentina.

Background: The Ziziphus mistol fruit (vulgar name mistol) is used in northwestern Argentina in traditional food and beverage preparations and popular medicines for liver and respiratory disorders. Aims: The aim of this research was to evaluate the hypoglycemic and anti-inflammatory activity in pulp powders and sub-products (skin and seeds) of mistol fruit, along with their toxicity. Methods: Powders from mistol seeds, pulp, and skin were obtained. Antioxidant capacity and inhibitory activity against key enzymes involved in metabolic syndrome were determined by in vitro assays. Results: The mistol powders obtained from the different fruit parts reduced glucose bioaccessibility. Before and after simulated gastroduodenal digestion, the polyphenol-enriched extracts (PEE) obtained from mistol powders increased glucose uptake by yeast cells and inhibited the pivotal enzymes of the inflammatory pathway (cyclooxygenase-2, lipooxygenase-1, and phospholipase A2). The analyzed mistol powders did not show acute toxicity or genotoxicity in model organisms and cell cultures. Conclusions: These results evince the potentiality of both the pulp from Z. mistol fruits and residual biomass (seeds and skin) to obtain biofunctional powders to use as supplements for metabolic disorders associated with chronic diseases.

Potential use of native fruits waste from Argentina as nonconventional sources of cosmetic ingredients.

Collagenase, hyaluronidase, elastase, and tyrosinase enzymes are overexpressed and overactive in the skin aging process and hydrolyze the components of the dermal extracellular matrix (ECM) of the skin; these enzymes produce the clinical framework of aging, which includes skin dryness, hyperpigmentation, wrinkles, and inelasticity. The aim of this study was to explore the potential use of waste from two Argentine native fruits, namely Ziziphus mistol, and red and orange varieties of Solanum betaceum, as sources of bioactive compounds. Phenolic enriched extracts (PEE) from waste of Z.mistol and S.betaceum were obtained, and their total contents of phenolics and flavonoids were evaluated. The bioactive properties of the extracts were analyzed by measuring their antioxidant capacity and the inhibitory activity on collagenase, hyaluronidase, elastase, and tyrosinase enzymes. The increased ability to inhibit the collagenase was demonstrated by the PEE of Z.mistol seeds and peel, while the enzyme elastase was mostly inhibited by extracts of S.betaceum skin. Z.mistol seed extract was the most active to inhibit hyaluronidase, reaching 96% inhibition at a concentration of 100μg GAE/mL. The most active extracts to inhibit the tyrosinase enzyme were obtained from the peel of two varieties of chilto fruits, orange and red, and the mistol seed. The results obtained suggest that Z.mistol and S.betaceum waste may be considered as a source of bioactive phenolics. Here, Argentine native fruits waste is presented as a most promising alternative in cosmetic products, with future uses such as hydrogels, creams, or lotions.

Assessment of pollen and honey diet of Tetragonisca angustula fiebrigi Schwarz in the Chaco dry forest by using pollen analysis

Pollen and honey resources composing the diet of Tetragonisca angustula fiebrigi Schwarz were assessed using pollen analysis of wild colonies sampled in two kinds of native dry forests of the Chaco region. Different measurements: direct pollen count, relative volume, diversity and evenness indices, value of importance of species (SI), and index of relative importance (IRI) were compared. The IRI identified the most important pollen resources as Prosopis (IRI = 1619), Schinopsis type (IRI = 1578), Trithrinax schizophylla (IRI = 972) and Capparicordis/Sarcotoxicum (IRI = 587), and according to SI the honey resources were Schinopsis type (SI = 117.41), Maytenus type (SI = 101.89), Prosopis (SI = 86.47) and Ziziphus mistol (SI = 50.93). The absolute pollen analysis of honey revealed that all samples were rich in pollen grains. Floral resources were most homogeneously foraged during spring and summer when a high number of flowerings were available and the highest temperatures were recorded. These optimal conditions for bee foraging activity also allowed for the highest diversity indices in these seasons. However, heterogeneous foraging and low diversity were detected during winter and autumn. Most pollen and honey resources belonged to generalised small flowers of diverse plant lineages. The IRI was more comprehensive to identify the most important pollen resources than the commonly used direct pollen count, as it also includes relative volume and frequency of occurrence, and SI was the most thorough for studying the honey resources. This study provides helpful information for sustainable meliponiculture and forest conservation.

Nutritional and nutraceutical compounds of fruits from native trees (Ziziphus mistol and Geoffroea decorticans) of the dry chaco forest

Mistol (Ziziphus mistol) and chañar (Geoffroea decorticans) fruits are traditionally used for both edible and medicinal purposes. The objective of the current study was to assess lipid, protein and phenolic composition from mistol and chañar fruits to provide better insights into their nutritional and nutraceutical properties. The total lipid content of whole fruits was found to be 9.8 % (mistol) and 21 % (chañar), and the contribution of essential polyunsaturated fatty acids (PUFA) was about 3.9 g PUFA/100 g and 11.5 g/100 g fruit, respectively. Lipids from mistol contained high amounts of total tocopherols (about 830 mg/kg). Fruits from both species showed relatively low protein contents (8 % mistol, 5 % chañar) with similar amino acids (AA) patterns. Essential AA represented about 28.3 % (mistol) and 31.5 % (chañar) of the total AA contents. The phenolic compounds from mistol fruits were dominated by flavonoids whereas those from chañar fruits comprised mainly phenolic acids, in particular hydroxycinnamic acid derivatives. Overall, findings from this study reinforce the value of mistol and chañar fruits as a source of nutritional and functional components.

Pollen diet assessment and flower association in Melipona orbignyi and recommendations on management and conservation of stingless bees in the Chaco dry forest of South America

Management and conservation of wild pollinators in forests of the Chaco region of South America is of great interest nowadays as they are pollen vectors that improve the reproductive success of many forest species which are at risk due mainly to forest patch isolation and degradation by human activities. The assessment of the diet of the stingless bee Melipona orbignyi was carried out by comparing different calculations from palynological data being the index of relative importance (IRI) the most complete, objective, and here recommended. This index showed that the order of the four most important pollen resources was Prosopis (IRI = 3354), Albizia inundata (1999), Cynophalla retusa (921), and Solanum type 2 (693), and the value of importance of species (SI) calculated for honey resources showed that they were type Maytenus (SI = 20.79), Prosopis (18.73), Cynophalla retusa (6.72), and Ziziphus mistol (3.32). Three flower types predominated in pollen and nectar provisions: brush flowers, solanoid flowers with poricidal anthers, and generalized small pale flowers, being the former two associated to buzzing. The abundance of the nectarless Solanum in honey samples is discussed. Good forest management practices for pollinator conservation native to the Chaco forest should include the keeping of undisturbed forest patches for nesting and foraging while the surrounding forest resources are managed in a sustainable way. Furthermore, because some threatened plants important for the M. orbignyi diet require gene flow to maintain healthy populations, short distances among the forest patches are needed, a fact that also helps to avoid genetic drift in Melipona colonies. The rational rearing of Melipona orbignyi would be a good practice to be implemented to promote pollination of threatened tree and shrub individuals isolated by forest fragmentation.

Chemical and functional characterization of skin, pulp and seed powder from the Argentine native fruit mistol (Ziziphus mistol). Effects of phenolic fractions on key enzymes involved in metabolic syndrome and oxidative stress

The mistol (Ziziphus mistol) is a native food tree occurring in dry areas of Northwestern and Central Argentina. Studies on its functional properties and bioactive compounds are scarce so far. In this work we assess the nutritional and functional components of lyophilized powder of mistol skin, pulp and seed. The powder from the different fruit parts have moderate carbohydrate content and are an important source of flavonoids, fiber, potassium, magnesium and calcium. The HPLC–ESI-MS/MS analysis of the polyphenols enriched extracts (PEE) of the samples allowed the identification of 17 compounds including 16 flavonoids and a procyanidin. The PEE showed antioxidant capacity and were able to inhibit α-glucosidase, α-amylase and pancreatic lipase, enzymes related to metabolic syndrome. The results suggest potential of the lyophilized skin, pulp and seed powder from mistol as functional food or dietary supplement in the prevention or treatment of diseases associated with metabolic syndrome.

Pollen analysis of honeys from the northwest of Argentina: Province of Jujuy

The palynological characterisation of 157 honey samples from three northwest regions of Argentina (Prepuna, Yungas and Chaco) are presented to determine their botanical origin and species associations to be able to define their geographic origin. Samples were harvested during 2003–2011 and processed by means of melissopalynological conventional techniques. One-hundred and nine pollen types were identified. Representative pollen types with a frequency of occurrence greater than 50% in descending order of importance are: Salix humboldtiana, Allophylus edulis, Baccharis, Solanaceae, Eucalyptus, Schinus, Brassicaceae, Papilionoideae, Celtis, Scutia/Condalia-type and Parapiptadenia excelsa. The most important monofloral honeys are from the following: Salix humboldtiana, Scutia/Condalia-type, Allophylus edulis, Baccharis, Blepharocalyx salicifolius, Gleditsia amorphoides, Myrtaceae, Sicyos, Ziziphus mistol, Schinopsis-type, Agonandra excelsa, Anadenathera colubrina, Mimosa, all of them native species, and among introduced species are Eucalyptus, Citrus and Tithonia. Three apicultural zones and their corresponding pollen association indicators were determined: Zone I, Prepuna: Arquita trichocarpa, Prosopis ferox, Schinus areira, Baccharis, Buddleja and Mutisieae; Zone II, Yungas: Myrtaceae, Parapiptadenia excelsa, Baccharis, Salix humboldtiana, Allophylus edulis, Scutia/Condalia-type and Zanthoxylum coco; Zone III, transitional area Yungas-Chaco: Prosopis, Salix humboldtiana, Schinus, Anadenanthera colubrina and Allophylus edulis.

RECURSOS VEGETALES Y PRÁCTICAS ALIMENTARIAS ENTRE INDÍGENAS TAPIETE DEL NORESTE DE LA PROVINCIA DE SALTA, ARGENTINA

Edible plant species and their parts used by indigenous tapiete people in northeastern Salta province, Argentina are identified, as well as their gathering, elaboration, consumption and storage practices. The ultimate aim of this work is to contribute to the recording and appreciation of tapiete people knowledge about this matter. Five fieldworks were made to the semiarid northern Chaco and to Tartagal city, where ethnobotanical data were obtained from 75 interviews with a total of 32 qualified and occasional tapiete collaborators. Each of the edible plants was collected and identified by the authors and deposited at the Ruiz Leal Herbarium (MERL). A total of 54 native plants, belonging to 23 botanical families used as food by the tapiete, are recorded as forming part of 106 preparations, or consumption forms, and 13 forms of conservation. The main edible species are Anisocapparis speciosa, Prosopis aff. elata and Prosopis alba with six applications each, and Ziziphus mistol, Geoffroea decorticans and Funastrum clausum with four applications each. Most of these applications (55%; 59) do not include any preparation –they are consumed raw-, the 21% (22) are eaten cooked (boiled or roasted), while their use in beverages, condiment and flours represent a minority of their applications (24%; 25). Consumption of the leaves of Passiflora mooreana and P. cincinatta is registered here for the first time by ethnic groups from the Gran Chaco.

Selection of Plants for Sap Feeding by the White-Fronted WoodpeckerMelanerpes cactorumin Chaco Dry Forest, Argentina

Abstract. Woodpeckers feed primarily on insects, larvae and other arthropods; however, several members of this family include plant products in their diets, such as sap. Among them, the genera Sphyrapicus and Melanerpes include the most species that specialize in sap consumption. In semiarid forests of Argentina, sap is an important food item in the diet of the White-fronted Woodpecker, Melanerpes cactorum. The aim of this study is to investigate why White-fronted Woodpeckers only consume sap from certain plants while avoiding other available plants of the same species and explore seasonality of their plant selection. We expected that combinations of plant traits (i.e. sugars concentration of sap, sap flow intensity, plant size, plant health and plant microhabitat), rather than one particular trait, determine which tree they select for sap feeding in different seasons. We examined five plant species: Sarcotoxicum salicifolium, Prosopis ruscifolia, Ziziphus mistol, Aspidosperma quebracho-blanco and Stetson...

ANTINOCICEPTIVE, ANTI-INFLAMMATORY EFFECTS AND SAFETY OF ZIZIPHUS MISTOL FRUITS

Ziziphus mistol Griseb. (Rhamnaceae), popularly known as “mistol,” is widely distributed throughout Perú, Bolivia, Paraguay and Argentina. Its fruit is consumed in different forms in several argentinean communities and used against biliary colic, dysentery, cold stomach and diseases of the respiratory system characterized by pain and inflammation. The present study was carried out to investigate the medicinal properties and safety of Ziziphus mistol (mistol) fruits ethanol and aqueous extracts and arrope. Antinociceptive activity was assessed using the formalin, acetic acid-induced writhing and tail-flick tests in rats. Anti-inflammatory effects were determined through carrageenan induced edema test and cotton pellet-induced granuloma formation, in rats. The safety was evaluated with test of acute toxicity (48 hours) and sub-chronic toxicity (91 days). All extracts (1,000 mg/kg b.w.) showed significant inhibition (P <0.05) in the three model of pain experimentally induced in comparison to control. In a combination test using naloxone, diminished analgesic activity of aqueous extract and arrope were observed, indicating that their antinociceptive activity is connected with the opioid receptors. At dose 1000 mg/kg bw, the aqueous extract and arrope showed higher anti-inflammatory activity than the ethanol extract, in carrageenan and cotton pellet granuloma model used. In the acute toxicity study, a single dose of 4000 and 8000 mg/kg b.w., produced no mortality and no clinical signs of disease were observed after 48 hours. In the sub-chronic toxicity study the extracts no caused significant visible signs of toxicity, nor mortality for 91 consecutive days of treatment. Extracts and arrope of Z. mistol fruits could be good source of antinociceptive and anti-inflammatory agents because of its good activity and safety.

Reproductive biology of Ziziphus mistol Griseb. (Rhamnaceae), a wild fruit tree of saline environments

Ziziphus comprises important fruit trees that inhabit arid environments of tropical and subtropical regions of the world and are able to adapt to drought and salt stress. Species of this genus are characterized by synchronous protandrous dichogamy and self-incompatibility; however, reduced seed set after hand self-pollination indicates that self-fertilization is possible and that it causes a strong inbreeding depression. We characterize the reproductive biology of Ziziphus mistol, a species typical of saline environments of Chaco American forests. For this purpose, we studied floral biology, observed foraging behavior and pollen load of captured floral visitors, and tested the breeding system through the assessment of fruit and seed set and pollen tube growth following self-, cross-, and open pollinations treatments. In addition, the dependence of a pollinator and autonomous self-pollination were evaluated by excluding floral visitors and airborne pollen. Cross-compatibility between individuals was tested through controlled hand pollinations. Results indicate that Z. mistol is predominantly outcrossing and depends on its pollinators to produce fruits and seeds. We observed high synchrony of flowering between individuals, as well as in floral anthesis between/within inflorescences within individuals. The flowers exhibit complete intrafloral dichogamy that fully prevents autonomous self-pollination, while sexual phases overlap within inflorescence; thus geitonogamy can easily occur. Manipulative experiments show that Z. mistol can set fruits and seeds after self- as well as cross-pollinations. However, reduction in fruit set and seed set after selfing and/or cessation of pollen tube growth in the style suggest a self-incompatible system. From reciprocal crosses tested (N=95), we have identified only 32.6% compatible crosses via fruit and seed trials. We suggest that in Z. mistol, as well as in other species of the genus, both synchrony in floral development and partial self-incompatibility would be evolved to reduce the costs of inbreeding.

Characterization of Argentine honeys on the basis of their mineral content and some typical quality parameters.

BackgroundThe levels of 19 elements (As, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Tl, U, V, Zn) from sixteen different Argentine production sites of unifloral [eucalyptus (Eucaliptus rostrata), chilca (Baccharis salicifolia), Algarrobo (Prosopis sp.), mistol (Ziziphus mistol) and citric] and multifloral honeys were measured with the aim to test the quality of the selected samples. Typical quality parameters of honeys were also determined (pH, sugar content, moisture). Mineral elements were determined by using inductively coupled plasma mass spectrometer (ICP-MS DRC). We also evaluated the suitability of honey as a possible biomonitor of environmental pollution. Thus, the sites were classified through cluster analysis (CA) and then pattern recognition methods such as Principal Component Analysis (PCA) and discriminant analysis (DA) were applied.ResultsMean values for quality parameters were: pH, 4.12 and 3.81; sugar 82.1 and 82.0 °brix; moisture, 16.90 and 17.00% for unifloral and multifloral honeys respectively. The water content showed good maturity. Likewise, the other parameters confirmed the good quality of the honeys analysed. Potassium was quantitatively the most abundant metal, accounting for 92,5% of the total metal contents with an average concentration of 832.0 and 816.2 μg g-1 for unifloral and multifloral honeys respectively. Sodium was the second most abundant major metal in honeys with a mean value of 32.16 and 33.19 μg g-1 for unifloral and multifloral honeys respectively. Mg, Ca, Fe, Mn, Zn and Cu were present at low-intermediate concentrations. For the other 11 trace elements determined in this study (As, Be, Cd, Co, Cr, Ni, Pb, Se, Tl, U and V), the mean concentrations were very low or below of the LODs. The sites were classified through CA by using elements’ and physicochemical parameters data, then DA on the PCA factors was applied. Dendrograms identified three main groups. PCA explained 52.03% of the total variability with the first two factors.ConclusionsIn general, there are no evidences of pollution for the analysed honeys. The analytical results obtained for the Argentine honeys indicate the products’ high quality. In fact, most of the toxic elements were below LODs. The chemometric analysis combining CA, DA and PCA showed their aptness as useful tools for honey’s classification. Eventually, this study confirms that the use of honey as biomonitor of environmental contamination is not reliable for sites with low levels of contamination.

A chemometric approach: characterization of quality and authenticity of artisanal honeys from Argentina

The demand of honey with defined quality has increased around the world; therefore, an adequate description of the traceability and authenticity of honeys is necessary. The pollen and physicochemical characteristics of 58 honey samples collected from five different environmental units (EUs) of the Jujuy province (Argentine) were determined, in order to differentiate them by geographical origin through the application of chemometric methods. A qualitative pollen analysis was performed by microscopy. The physicochemical characteristics were determined by Association of Official Analytical Chemists methods. Correspondence analysis (CA), principal component analysis (PCA) and linear discriminant analysis (LDA) were performed. Forty‐five per cent of honeys were monofloral; nearly half of them correspond to native species—among which, Salix humboldtiana, Baccharis sp. and Ziziphus mistol stood out. Physicochemical and microbiological analysis showed acceptable quality for honeys. CA characterized significantly honeys from four different EUs using all pollen data. While forward stepwise coupled to LDA identified 14 significant variables to build a discriminatory model with three significant discriminant functions, a cumulative variance of 94% was reached. Thus, 86% of the samples were correctly classified. PCA and LDA applied to physicochemical data allowed to distinguish three different groups with a significant function (p < 0.01) that explained 90% of the total variability. Honey corresponding to EU III Subandean Hills of Santa Bárbara was the most accurately classified by pollen and physicochemical data. The application of chemometric methods to pollen data and physicochemical parameters may be a useful tool to determine honey geographical origin. Copyright © 2014 John Wiley & Sons, Ltd.

Response of hardwood tree regeneration to surface fires, western Chaco region, Argentina

We assessed the response of seedlings and pole-sized individuals of Aspidosperma quebracho-blanco Schlecht., Schinopsis lorentzii (Griseb.) Engler and Ziziphus mistol Griseb. to surface fires. We assessed traits of fire resistance (bark thickness and bark density) and fire tolerance (mortality and sprouting type, basal or epicormic) in each species. Burns were carried out using two fine fuel loads (high, 8000kgha−1; and low 4000kgha−1, respectively) and two dates of fire application (early and late fire season). Field work was performed during 2008 and 2009. Using a randomized design, 120 2m×2m plots were burnt each year. Using ANOVA, we tested the effect of species, fuel load and date of fire on the bark char height of the bole. The resprouting pattern (basal or epicormic) and post-fire mortality (complete or top-kill) were analysed using a logistic regression approach. There were a significant effect of species (p<0.0001), fuel load (p<0.0001) and of the interaction year of burning *date of fire (p<0.0001) on the mean char height. A. quebracho-blanco had greater char height than S. lorentzii and Z. mistol (p<0.05), but differences between the latter two species were no significant. Diameter to breast height (DBH) was significant and positively correlated to char height for A. quebracho-blanco and Z. mistol. High fuel load produced higher char height than the low fuel load fires. A. quebracho-blanco had the greatest total, inner and outer bark thickness, and the lowest bark density among the studied species. It was followed by S. lorentzii, while Z. mistol had the lowest total bark thickness, the highest inner bark proportion and the highest bark density (p<0.05). The likelihood of complete mortality was significantly larger in Z. mistol than in A. quebracho-blanco and S. lorentzii. Mortality and top-kill were lower in the late season burns (p<0.05). Sprouting type was significantly affected by species (p<0.05), DBH, date of fire and by the interactions species×DBH and season of fire×DBH (p<0.0001). A. quebracho-blanco presented only basal resprouts, while the other two species showed both epicormic and basal resprouts. The two species with greater bark thickness had lower mortality than Z. mistol. Epicormic resprouts were not observed at the more severe late burns. The three species studied showed high resistance and tolerance to medium to high severity fires.

Inhibition of cytotoxicity of Shiga toxin of Escherichia coli O157:H7 on vero cells by Prosopis alba Griseb (Fabaceae) and Ziziphus mistol Griseb (Rhamnaceae) extracts.

The capacity of Prosopis alba Griseb. and Ziziphus mistol Griseb. fruit extracts to inhibit the toxic action of Shiga toxin (Stx) was investigated. Purification of Stx from Escherichia coli O157:H7 was performed by saline precipitation and affinity chromatography using a column with globotriaosylceramide, while the fruits were subjected to ethanolic or aqueous extractions. The protective action of both fruits was determined by pre-, co-, and postincubation of one 50% cytotoxic dose per ml of Stx with different concentrations of ethanolic and aqueous extracts in confluent monolayers of Vero cells for 72 h at 37°C (5% CO2). The inhibition of the cytotoxic effect of Stx by fruit extracts was determined by the neutral red vital staining technique. The extraction of the polyphenols and flavonoids was effective, and more polyphenols per milligram of dissolved solids were obtained from P. alba than from Z. mistol. However, there were more flavonoids in Z. mistol than in P. alba. Components of both fruits increased the viability of cells treated with Stx when the extracts were preincubated with Stx for 1 h before being applied to the cell cultures, with the ethanolic extract of P. alba showing 95% cell viability at a concentration of 2.45 mg/ml. The extracts were less effective in protecting cells when Stx, extracts, and cells were coincubated together without a previous incubation of Stx; only the concentrations of 19.46 mg/ml for the P. alba aqueous extract and 3.75 mg/ml for the Z. mistol ethanolic extract resulted in the inhibition of cytotoxicity, with 52 and 56% cell viability occurring, respectively. Investigation into this difference in the protection of cells indicated that the protein molecule of Stx suffered degradation to advanced oxidative protein products during preincubation with extracts, principally with P. alba, which exhibited a greater amount of nonflavonoid polyphenols than Z. mistol. The prooxidant action on Stx favored the cells and enhanced the protective action of both fruits.

Nitrosylation: An adverse factor in Uremic Hemolytic Syndrome. Antitoxin effect of Ziziphus mistol Griseb

Toxins of Escherichia coli (STEC) causing Uremic Hemolytic Syndrome (UHS) generate oxidative stress in human blood with more production of nitric oxide (NO) than reactive oxygen species (ROS). Shiga toxin (Stx) together with the hemolysin (Hly) increased lipid oxidation, as evaluated by malondialdehyde MDA and oxidation of proteins. The addition of Ziziphus mistol Griseb extracts decreased NO, ROS, MDA and simultaneously caused an increase in the degradation of oxidized proteins to advanced oxidation protein products (AOPPs) in controls and samples with toxins. Furthermore, the nitrosylated proteins/AOPP ratio was reduced, due to the increase of AOPP. Z. mistol Griseb extracts exhibited a high proportion of polyphenols and flavonoids, with evident correlation with ferrous reduction antioxidant potential (FRAP). The plasma of eight children with UHS showed oxidative stress and NO stimulus, comparable to the effect of toxins during the assays in vitro. UHS children presented high levels of nitrosylated proteins respect to control children of similar age. Although the degradation of oxidized proteins to AOPP rose in UHS children, the nitrosylated proteins/AOPP rate increased as a consequence of the elevated nitrosative stress observed in these patients.

Antioxidant and anti-inflammatory activity characterization and genotoxicity evaluation of Ziziphus mistol ripe berries, exotic Argentinean fruit

Ziziphus mistol Griseb. (Rhamnaceae), popularly known as “mistol,” is widely distributed throughout Perú, Bolivia, Paraguay and Argentina. Its fruit is consumed in different forms in several Argentinean communities. The aim of this work is to quantify Z. mistol fruit macronutrients and phytochemicals as well as to determine its functional antioxidant and anti-inflammatory properties and toxicity after two different processes: boiling and hydroalcoholic extraction. Phytochemical recovery was variable depending on the extraction method used. All preparations showed antioxidant activity, but the ethanolic one (EME) was significantly more active than the aqueous one (AME) as hydrogen or electron donors with SC50 values between 1.45 to 6.31μgGAE/mL and 7.38 to 64.77μgGAE/mL, respectively. The aqueous extraction was significantly more active than EME on superoxide and hydroxyl radical scavenging. Polyphenols showed a dose–response relationship (R2>0.90) with antioxidant capacity in the decoction and the alcoholic beverage. The maceration showed an inhibitory effect on lipoxygenase (LOX) activity with an inhibitory concentration (IC50) value of 183.80μg gallic acid equivalents (GAE)/mL but the decoction did not. On the other hand, extracts did not show any mutagenic effect. Therefore, mistol fruits consumption could be encouraged not only for its functional properties, but also because of the positive ecological impact of preserving biological diversity through the exploitation of native natural resources in a regional economy.

Floral resources foraged by Geotrigona argentina (Apidae, Meliponini) in the Argentine Dry Chaco forest

This study is the first contribution to knowledge of the relationships between Geotrigona argentina and the plants of the Argentine Dry Chaco forest. A total of 1260 g of honey (corresponding to 146 pots) and 763 g of pollen (63 pots) stored in four underground nests was studied. The honey pots from each nest were homogenised and the four honey samples were analysed by melissopalynological methods, whereas the pollen pots were studied individually. Both classical counts and counts affected by the volume of the pollen types were carried out. Pollen data were statistically analysed. Additional data on both protein and lipid content is also provided. A total of 39 pollen taxa were identified. Pollen collection was focused on a few pollen taxa: Prosopis, Castela coccinea, Maytenus and Capparis; these taxa, together with Ziziphus mistol and Pisonia zapallo, were also important nectar sources. The preliminary results show that pollen collection varied seasonally, being most diverse in the summer when G. argentina incorporates herbaceous plants into its diet. The pollen collection spectrum of G. argentina is similar to that of other Trigonina bees in that the main plant species collected are a few large shrubs or trees, whose flowering consists of small and clustered flowers. Pots with large amounts of monofloral loads with pollen from only a few species suggests an organised foraging behaviour that includes the recruitment of foragers, such as that observed in other eusocial bees.

Seasonal Diet of the Pampas Fox (Lycalopex gymnocercus) in the Chaco Dry Woodland, Northwestern Argentina

The seasonal diet of Pampas foxes (Lycalopex gymnocercus) was examined from 431 scat samples collected during 1 year in the dry Chaco woodland of Salta Province, northwestern Argentina. Fleshy fruits dominated the diet during the dry and wet seasons, representing 69% of the total frequency and comprising 91% of the total volume. Most of the fruit diet was contributed by 5 woody plant species. Mistol (Ziziphus mistol, Rhamnaceae), was the most important fruit resource throughout the year. Arthropods (particularly beetles and scorpions) and small mammals (mainly rodents and marmosets) were the most frequently consumed animal prey. Seasonal shifts in the frequency of the main food items in the diet were not significant, but there was considerable seasonal variation in the frequency of fruit species. Diversity of prey in the diet was highest in the wet season. The Pampas fox is a generalist feeder that can alter its diet to changes in food availability. However, its diet in the Chaco, which is dominated by fruit, differs from its diet in Pampas grassland habitat, where it consumes mostly meat.

Passage time, viability, and germination of seeds ingested by foxes

Seed passage through the gut of vertebrates is critical for endozoochorus seed dispersal because it may influence seed viability and germination capacity. Foxes are important fruit-eaters and presumed seed dispersers in the Chaco ecoregion. We experimentally assessed the seed passage time (SPT) and its effect on seed viability and germination in two fox species ( Pseudalopex gymnocercus and Cerdocyon thous) that occur in the Chaco. Passage time was measured using both artificial seeds of three sizes and wild seeds of four native fleshy-fruit species commonly consumed by foxes ( Ziziphus mistol, Acacia aroma, Celtis tala, and Syagrus romanzoffiana). The average SPT was 6.8 h for the Pampa fox and 7.7 h for the crab-eating fox. Passage time did not differ either among seeds of different sizes or between fox species. Passage through digestive tract of both fox species did not affect seed survival, whereas germination rate was slightly improved. Our data suggest that both fox species are legitimate seed dispersers of the four species studied, having a positive effect on both germination rate and dispersal distance from the parent plant.