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2012) Composition and antioxidant activity of honey from Africanized and stingless bees in Alagoas (Brazil): a multivariate analysis, Journal of Apicultural Research, 51:1, 23-35 To link to this article: http://dx. SummaryThe purpose of this study was to evaluate the antioxidant activity of honey from different entomological sources which were harvested in the dry season of 2008-2009 from distinct mesoregions of the State of Alagoas in the North East of Brazil. Honey produced by five different species of bees, even from the same region and season, showed a statistically significant difference (p <0.05) in the content of phenols, flavonoids and antioxidants, with higher levels of these compounds found in honey produced by Plebeia spp. and A. mellifera. Honey from stingless bees was quite different from that of A. mellifera, especially from the Plebeia spp. A dendrogram of the five species of bees showed the formation of 3 groups, one being formed by Apis mellifera, one by the genus Melipona (M. subnitida, M. quadrifasciata and M. scutellaris) and another formed by Plebeia spp.Composición y actividad antioxidante de la miel de abejas africanizadas y sin aguijón en Alagoas (Brasil): un análisis multivariante Resumen El propósito de este estudio fue evaluar la actividad antioxidante de la miel de diferentes fuentes entomológicas que se recogieron en la estación seca de 2008-2009 de distintas mesorregiones del Estado de Alagoas en el noreste de Brasil. La miel producida por cinco especies distintas de abejas, incluso de la misma región y de temporada, mostró una diferencia estadísticamente significativa (p < 0,05) en el contenido de fenoles, flavonoides y antioxidantes, con mayores niveles de estos compuestos se encuentran en la miel producida por Plebeia spp y A. mellifera. La miel de las abejas sin aguijón era muy diferente de la de A. mellifera, especialmente de las especies de Plebeia. Un dendrograma de las cinco especies de abejas mostró la formación de tres grupos, uno de ellos formado por Apis mellifera, uno por el género Melipona (M. subnitida, M. quadrifasciata y M. scutellaris) y otro formado por Plebeia spp.M. scutellaris, this parameter varied from 4.67-52.56 mg GA equivalent / 100 g (mean 18.45 ± 11.41 mg. GA equivalent / 100 g), being lower than in honey from Apis, Fig. 1.In honey from M. quadrifasciata, M. subnitida and Plebeia spp., the antioxidants averages, according to this method were 32.96 ± 30.67, 16.19 ± 5.76 and 49.91 ± 21.36 mg GA equivalent / 100 g, respectively. Statistically significant correlations (p < 0.01) were observed between the content of total phenolics and FRAP (r = 0.814) and between the total flavonoid content and FRAP (0.795), demonstrating, again, the contribution of these compounds in the antioxidant activity of honey. There was also a statistically significant correlation between the content expressed by FRAP and the antioxidant content by DPPH expressed as GA (r = 0.584) and Q (r = 0.568), Table 2. Detection of antioxidant compounds by TLCRegarding the identification of ant...

(Dnline) 2 Materials and methods 2.1 Samples of honey and bee pollen from meliponini species Different samples of honey (n = 31) and bee pollen (n = 25), respectively from seven stingless bees species: Melipona asilvai Moure (1971); M. quadrifasciata anthidioides Lepeletier (1836); M. scutellaris Latreille (1811); M. subnitida Ducke (1910); Frieseomelitta varia Lepeletier (1836); Tetragona clavipes Fabricius (1804) and Plebeia sp., and six of such species (all the above mentioned less F. varia) were collected in four private

Extraction temperature, extraction time and liquid (water) to solid ratio were optimized in order to extract antioxidant phenolic compounds from brewers’ spent grain (BSG). The extracts were analysed for their total phenol content (TPC) and antioxidant activity was measured using three different methods: 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical, 2,2′-azino-bis(3-ethylbenothiazoline-6-sulphonic acid) (ABTS), and reducing power (RP) assays. All the parameters except extraction time promoted different efficiencies for the extraction of antioxidant phenolic compounds. TPC extraction was higher at lower temperatures and lower liquid/solid ratios up to a certain point. In this sense, a decrease in TPC with increasing liquid/solid ratios took place until a 16:1 ratio and a plateau was reached beyond that ratio. The highest DPPH activity was reported for 30–35 °C and 60–90 min extraction and 60–90 min extraction with a 25 mL/g ratio. ABTS values increased as the liquid to solid ratio decreased, being positively correlated with TPC (R = 0.788; p < 0.01). The highest RP was achieved at 30–33 °C extraction temperature and 10–14 mg/mL v/w ratio and at 116–120 min extraction and 16–17 mg/mL ratio. Gallic acid accounted for the majority of the phenolic compounds found, followed by hydroxyphenylacetic acid, epicatechin, and protocatechuic acid. Sinapic, 4-hydroxy benzoic, and syringic acids were also found in lower quantities. Coumaric, vanillic, ferulic, and caffeic acids were present in very small amounts. All the extracts contained phenolics and showed in vitro antioxidant activity, but the extracts obtained by using 30 °C, 121.9 min, and 10 mL/g liquid/solid ratio exhibited the highest content in TPC and antioxidant potential. The aqueous extraction of a potentially bioactive extract from BSG was demonstrated to be an efficient and simple method to recover these value-added compounds.

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Sorghum mesocotyls upon mechanical injury with an abrasive (carborundum) or inoculation with the fungi Helminthosporium carbonum (non‐pathogen) or Colletotrichum graminicola (pathogen) accumulate a methanol‐soluble pigment complex with an absorption maximum around 480–490 nm. Spectral and thin‐layer chromatographic analyses showed that the complexes which accumulated either in response to wounding or inoculation are similar. Thus, it is suggested that the accumulation of the pigmented phytoalexins in sorghum mesocotyls is a non‐specific response of the tissues towards mechanical injury or fungal infection.

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Article Info Fungus/Allergen Size (kD) Biological Activity Sequence access number Penicillium brevicompactum Pen b 13 33 Alkaline serine protease * Pen b 26 11 Ribosomal acid protein 60S AY786077 Penicillium chrysogenum Pen ch 13 34 Alkaline serine protease AF193420 Pen ch 18 32 Vacuolar serine protease AF264027 Pen ch 20 68 N-acetyl-glucosaminidase S77837 Pen ch 31 Calreticulin AY850367 Pen ch 33 16 unknown EF206657.1 Pen ch 35 36.5 Transaldolase GQ925430 Penicillium citrinum Pen c 3 18 Peroxisomal membrane protein AF144753 Pen c 13 33 Alkaline serine protease * Pen c 19 70 Heat shock protein P70 U64207 Pen c 22 46 Enolase AF254643 Pen c 24 Elongation factor 1β AY363911 Pen c 30 97 Catalase DQ288844 Pen c 32 40 Pectate lyase EF159713 Penicillium crustosum Pen cr 26 11 Acid ribosomal phosphoprotein P1 60s JN791438 Penicillium oxalicum