Browsing by Author "Montenegro, Gloria"

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    Aplicación de la Norma Chilena Oficial de denominación de origen botánico de la miel para la caracterización de la producción apícola.
    (2008) Montenegro, Gloria; Gómez, Miguel; Díaz-Forestier, Javiera; Pizarro, Rodrigo
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    Changes in the antibacterial capacity of Ulmo honey in relation to the contribution of Eucryphia cordifolia pollen
    (VUP FOOD RESEARCH INST, BRATISLAVA, 2021) Montenegro, Gloria; Velasquez, Patricia; Viteri, Rafael; Giordano, Ady
    Ulmo honey is known for its antibacterial characteristics. However, the importance of the content from Eucryphia cordifolia in the honey regarding its non-peroxidic antibacterial capacity is unknown. The present work evaluated the antibacterial activity of Ulmo honey with various percentages of pollen from E. cordifolia against various bacteria, determine the non-peroxidic capacity of Ulmo honey and, finally, compare that capacity with Manuka and Jarrah honeys. The antibacterial activity was evaluated by agar diffusion test and the non-peroxide capacity was evaluated by the reactivity with the catalase enzyme. The tests were carried out against Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes. The results showed a relationship between the percentage of floral pollen from E. cordifolia and the antibacterial activity of Ulmo honey. It was also observed than the antibacterial activity of Ulmo honey can have values similar to Manuka and Jarrah honeys.
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    Characterisation of seed dormancy of 12 Chilean species of Nolana (Solanaceae) from the coastal Atacama Desert
    (CAMBRIDGE UNIV PRESS, 2021) Hepp, Josefina; Gomez, Miguel; Leon Lobos, Pedro; Montenegro, Gloria; Vilalobos, Luis; Contreras, Samuel
    The genus Nolana (Solanaceae) comprises numerous species endemic to the coastal Atacama Desert of Chile and Peru of high ornamental potential and conservation value. The environments in which these species have evolved and are present today correspond to particular conditions in the midst of a hyper-arid habitat, so the study of their germination requirements and characterisation of seed dormancy becomes important in terms of conservation but also for ecological and evolutionary purposes. Different treatments were performed on mericarps of 12 species of Nolana: control (intact seeds imbibed in distilled water), scarification in funicular plug and distilled water and scarification in funicular plug and addition of GA(3) (500 ppm); their permeability to water was also tested. It was determined that the species did not present physical dormancy, as had been previously reported, but rather physiological dormancy (PD). Germination results after treatments were not homogeneous among all 12 species, indicating differences in their dormancy levels. Also, the important role of the endosperm in the prevention of germination for the studied Nolana species was highlighted. Regarding the relationship between the level of PD (expressed as the percentage of germination for the most successful treatment) and the latitudinal distribution of the species or their phylogenetic closeness, it was determined that, for the studied species, their proximity in terms of clades was more relevant than their latitudinal distribution.
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    Chilean native species as source of natural polyphenols
    (CABI, 2013) Fredes, Carolina; Montenegro, Gloria; Céspedes, Carlos L.; Sampietro, Diego A.; Sigler, David; Rai, Mahendra
    This chapter discusses the traditional uses of native medicinal plants from Chile and provides tabulated data on Chilean medicinal plants, including the parts used and their effects, in order to analyse compounds that could be responsible for these medicinal effects. It presents scientific evidence supporting biological activity associated with the presence of polyphenols in Chilean plants. The determination of polyphenols in Chilean plants and their antioxidant capacity are described. The main factors affecting polyphenol content in plants are also mentioned, i.e. genotype, environment, storage and processing, and stage of harvest.
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    Eucryphia cordifolia extracts: Phytochemical screening, antibacterial and antioxidant activities
    (2021) Viteri, Rafael; Giordano, Ady; Montenegro, Gloria; Zacconi, Flavia C. M.
    Eucryphia cordifolia is a native and dominant species from the Temperate Forest in the southern region of Chile. It is a crucial melliferous species producing unifloral honey with outstanding antibacterial properties with great commercial value at international markets. A phytochemical screening was developed by colorimetric and gravimetric methods. Antioxidant activities were assessed by using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric ion reducing antioxidant power (FRAP) method. The minimum bactericidal concentration (MBC) was the method used to determine the antibacterial activity. The results revealed the highest antioxidant activity for the methanolic extracts of branches (IC50 35.7 mu g/mL for DPPH, IC50 11.0 mu g/mL for ABTS, and 4.6 mM FeSO4 center dot 7H(2)O/g in FRAP), attributed to its high content of total phenols (332.8 mg GAE/g). The quantification of the MBC led to values in the range of 0.78-12.5 mg/mL for S. aureus and S. pyogenes, and 6.25-50 mg/mL for E. coli and P. aeruginosa, respectively. The presented work provides valuable first in vitro evidence regarding the potential application of E. cordifolia extracts as antioxidants and antibacterial agents in the nutraceutical and phytopharmaceutical industry.
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    Floral Pollen Bioactive Properties and Their Synergy in Honeybee Pollen
    (2023) Velásquez, Patricia; Muñoz-Carvajal, Eduardo; Grimau, Lissette; Bustos, Daniela; Montenegro, Gloria; Giordano, AdyVelásquez, Patricia; Muñoz-Carvajal, Eduardo; Grimau, Lissette; Bustos, Daniela; Montenegro, Gloria; Giordano, Ady
    Honeybee pollen (HBP) is a mixture of floral pollen collected by honeybees near the hive. It is characterized by a composition rich in phenolic compounds, carotenoids and vitamins that act as free radicals scavengers, conferring antioxidant and antibacterial capacity to the matrix. These bioactive properties are related to the botanical origin of the honeybee pollen. Honeybee pollen samples were collected from different geographical locations in central Chile, and their total carotenoid content, polyphenols profile by HPLC/MS/MS, DPPH radical scavenging capacity, and antimicrobial capacity against S. pyogenes, E. coli, S. aureus, and P. auriginosa strains were evaluated. Our results showed a good carotenoids content and polyphenols composition, while antioxidant capacity presented values between 0–95 % for the scavenging effect related to the botanical origin of the samples. Inhibition diameter for the different strains presented less variability among the samples, Furthermore, binary mixtures representing the two most abundant species in each HBP were prepared to assess the synergy effect of the floral pollen (FP) present in the samples. Data shows an antagonist effect was observed when assessing the carotenoid content, and a synergy effect often presents for antimicrobial and antioxidant capacity for bee pollen samples. The bioactive capacities of the honeybee pollen and their synergy effect could apply to develop new functional ingredients for the food industry.
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    Nutritional and antioxidant potential of Chilean native fruits: lleuque (Prumnopitys andina) and copihue (Lapageria rosea)
    (VUP FOOD RESEARCH INST, BRATISLAVA, 2021) Giovagnoli vicuna, Claudia; Velasquez, Patricia; Montenegro, Gloria; Espejo, Jaime; Gomez, Miguel; Cabrera barjas, Gustavo; Giordano, Ady
    Nutritional and antioxidant properties of pulp and seeds of lleuque (Prumnopitys andina) and copihue (Lapageria rosea) were investigated. Proximal analysis revealed that the pulps are rich in carbohydrates, whereas the seeds are a good source of fibre. Both pulps exhibited higher phenolics content (PC) and flavonoids content (FC), as well as antioxidant capacities, compared to seeds. The data showed that PC correlated with antioxidant capacity the strongest, followed by FC and anthocyanins content. It was observed that global antioxidant score and relative antioxidant capacity index represented the antioxidant capacity behaviour of the extracts. According to the polyphenol antioxidant coefficients calculation, PC was an important contributor to antioxidant capacity of all extracts. The results of this study confirmed that the native Chilean fruits lleuque and copihue are an excellent source of antioxidants.
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    Phenolic profiles of nectar and honey of Quillaja saponaria Mol. (Quillajaceae) as potential chemical markers
    (2013) Montenegro, Gloria; Rodríguez, Sharon; Fredes, Carolina; Díaz-Forestier, Javiera
    Quillaja saponaria Mol. (Quillajaceae) is one of the most important melliferous species in Chile, mainly as a source of monofloral honey. Honey made by A. mellifera presents biological activity against pathogens and antioxidant capacity associated with the presence of phenolic compounds deriving from the nectar, as a result of bee honey foraging. The aim of this study was to identify and quantify the phenolic compounds from the floral nectar of Q. saponaria and the honey made in apiaries in the central zone, and compare the composition of the chromatographic profiles of nectar and honey to known phenolic compounds. The results obtained by HPLC-DAD (high-performance liquid chromatography with diode-array detection) showed a similar profile of phenolic compounds, in which gallic acid, myricetin, rutin, quercetin and naringenin were identified. The phenolic compounds detected could be used as a reference for future studies for determining potential chemical markers of this honey, complementing the present identification of honeys by determining their botanical origin. The identification of bioindicators of the floral origins for honey of this species could provide added value to honey commercialization by certifying the botanical origin of their chemical features and biological attributes.
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    The antifungal effect of six commercial extracts of Chilean propolis on Candida spp..
    (2010) Herrera, Christian L.; Alvear, Marysol; Barrientos, Leticia; Montenegro, Gloria; Salazar, Luis A.