3 research outputs found
Variability in Foliar Ellagitannins of <i>Hippophaë rhamnoides</i> L. and Identification of a New Ellagitannin, Hippophaenin C
Berries
of common sea-buckthorn (<i>Hippophaë rhamnoides</i> L.) are well-known and used for their bioactive components, and
while there is a considerable amount of research on the leaves as
well, their ellagitannins (ETs) have not been a prominent focus of
research. We identified and quantified ten major hydrophilic polyphenols,
all ETs, in <i>H. rhamnoides</i> leaves and compared
their abundance between 58 plant individuals. Of these compounds,
hippophaenin C was characterized as a new ellagitannin by various
spectrometric methods. The total concentrations of ETs ranged from
42.5 mg g<sup>–1</sup> dry weight (DW) to 109.1 mg g<sup>–1</sup> DW between individual plants. Among the ETs, hippophaenin C, stachyurin,
and casuarinin were on average the most abundant compounds. Sexes
did not differ significantly, while cultivars showed variation in
some ETs. These results suggest that <i>H. rhamnoides</i> leaves could be a potential and rich source of several ETs
Rapid Qualitative and Quantitative Analyses of Proanthocyanidin Oligomers and Polymers by UPLC-MS/MS
This paper presents the development
of a rapid method with ultraperformance
liquid chromatography–tandem mass spectrometry (UPLC-MS/MS)
for the qualitative and quantitative analyses of plant proanthocyanidins
directly from crude plant extracts. The method utilizes a range of
cone voltages to achieve the depolymerization step in the ion source
of both smaller oligomers and larger polymers. The formed depolymerization
products are further fragmented in the collision cell to enable their
selective detection. This UPLC-MS/MS method is able to separately
quantitate the terminal and extension units of the most common proanthocyanidin
subclasses, that is, procyanidins and prodelphinidins. The resulting
data enable (1) quantitation of the total proanthocyanidin content,
(2) quantitation of total procyanidins and prodelphinidins including
the procyanidin/prodelphinidin ratio, (3) estimation of the mean degree
of polymerization for the oligomers and polymers, and (4) estimation
of how the different procyanidin and prodelphinidin types are distributed
along the chromatographic hump typically produced by large proanthocyanidins.
All of this is achieved within the 10 min period of analysis, which
makes the presented method a significant addition to the chemistry
tools currently available for the qualitative and quantitative analyses
of complex proanthocyanidin mixtures from plant extracts
Drought Effects on Proanthocyanidins in Sainfoin (Onobrychis viciifolia Scop.) Are Dependent on the Plant’s Ontogenetic Stage
Sainfoin
(Onobrychis viciifolia Scop.)
is a forage legume, which improves animal health and the environmental
impact of livestock farming due to its proanthocyanidin content. To
identify the impact of drought on acetone/water-extractable proanthocyanidin
(PA) concentration and composition in the generative and vegetative
stages, a rain exclosure experiment was established. Leaves of 120
plants from 5 different sainfoin accessions were sampled repeatedly
and analyzed by UPLC-ESI-MS/MS. The results showed distinct differences
in response to drought between vegetative and generative plants. Whereas
vegetative plants showed a strong response to drought in growth (−56%)
and leaf PA concentration (+46%), generative plants showed no response
in growth (−2%) or PA concentration (−9%). The PA composition
was stable across environments. The five accessions varied in PA concentrations
and composition but showed the same pattern of response to the experimental
treatments. These results show that the ontogenetic stage at which
drought occurs significantly affects the plant’s response