27 research outputs found
The Relationships between Phenolic Content, Pollen Diversity,Physicochemical Information and Radical Scavenging Activity in Honey
Honey is rich in different secondary plant metabolites acting as natural antioxidants and contributing to human health. Radical scavenging activity (RSA) is related to antioxidant activity, while the correlation between the phenolic content and RSA is often weak. Consequently, exclusive information on phenolics is often insufficient to qualify the RSA and the health promoting effects of honey. The paper deals with a case study of honey samples originating from the alpine areas of Italy\u2019s Lombardia and Veneto regions and realized by standard physicochemical and statistical analytical methods. In pure honey, the total phenolic content and the RSA were measured in spectrophotometric tests with the 2,2-diphenyl-1-picrylhydrazyl (DPPH\ub7) free radical and Folin-Ciocalteu assays, respectively. Melissopalynological data was used to qualify pollen diversity through rank-frequency curves separating the samples into two groups. On the basis of physicochemical data, the samples were analyzed through multivariate classification and ranking procedures resulting in the identification of an outlier. Elimination of the outlier produced a high correlation between the total phenolic content and RSA in the two pollen diversity groups. The case study suggests that, after disregarding outliers, the RSA activity can be satisfactorily qualified on the basis of phenolics with pollen diversity as a covariate
The bacterial community associated to an Italian population of Psacothea hilaris: a preliminary study
The yellow
-
spotted longicorn beetle,
Psacothea hilaris
(Pascoe)
(Coleoptera Cerambycidae), native to eastern Asia, is an invasive
species for Europe, where it is present since 2005 as a pest of
Morus
and
Ficus
spp. Up to
date, no study on the bacterial comm
u-
nity associated with
P. hilaris
has been carried out. The aim of the present work is to characterize the bacterial community ass
o-
ciated to an Italian population of
P. hilaris
collected on
F. carica
L. through a culture
-
independent method (i.e., 454 pyrosequen
c-
ing) targe
t
ing the 16S rRNA gene. The DNA used for bacterial characterization has been extracted from the whole abdomen of 15
adults (seven males and eight females) sampled on the host plant immediately after their
emergence in Alserio (Como, Italy) b
e-
tween August and September 2012. The sequencing strategy led to a total of
≈
2,350
bacterial 16S rRNA gene sequences that
have been clustered into
141 bacterial operational taxonomic units.
Results shown that t
he bacterial community was dominated by
Prote
o
bacteria (86%) belonging to Oxalobacteraceae and Enterobacteriaceae (respec
tively 36.4% and 34.8%).
Pantoea
resulted
the most abundant genus (28.4%), and the other relevant bacterial genera associated with
P. hilaris
are
Ralstonia
(18.6%),
Meth
y-
lobact
e
rium
(3%),
Lactococcus
(2%) and
Propionibacterium
(1.4%)