Ilaria Bruni

Identification of poisonous plants by DNA barcoding approach

The plant exposures are one of the most frequent poisonings reported to poison control centres. The diagnosis of intoxicated patients is usually based on the morphological analysis of ingested plant portions; this procedure requires experience in systematic botany, because the plant identification is based on few evident traits. The objective of this research is to test DNA barcoding approach as a new universal tool to identify toxic plants univocally and rapidly. Five DNA barcode regions were evaluated: three cpDNA sequences (trnH-psbA, rpoB and matK) and two nuclear regions (At103 and sqd1). The performance of these markers was evaluated in three plant groups: (1) a large collection of angiosperms containing different toxic substances, (2) congeneric species showing different degrees of toxicity and (3) congeneric edible and poisonous plants. Based on assessments of PCR, sequence quality and resolution power in species discrimination, we recommend the combination of plastidial and nuclear markers to identify toxic plants. Concerning plastidial markers, matK and trnH-psbA showed consistent genetic variability. However, in agreement with CBOL Plant Working Group, we selected matK as the best marker, because trnH-psbA showed some problems in sequences sizes and alignments. As a final and relevant observation, we also propose the combination of matK with a nuclear marker such as At103 to distinguish toxic hybrids form parental species. In conclusion, our data support the claim that DNA barcoding is a powerful tool for poisonous plant identifications.

A DNA barcoding approach to identify plant species in multiflower honey

The purpose of this study was to test the ability of DNA barcoding to identify the plant origins of processed honey. Four multifloral honeys produced at different sites in a floristically rich area in the northern Italian Alps were examined by using the rbcL and trnH-psbA plastid regions as barcode markers. An extensive reference database of barcode sequences was generated for the local flora to determine the taxonomic composition of honey. Thirty-nine plant species were identified in the four honey samples, each of which originated from a mix of common plants belonging to Castanea, Quercus, Fagus and several herbaceous taxa. Interestingly, at least one endemic plant was found in all four honey samples, providing a clear signature for the geographic identity of these products. DNA of the toxic plant Atropa belladonna was detected in one sample, illustrating the usefulness of DNA barcoding for evaluating the safety of honey.

Phytotoxic and genotoxic effects of silver nanoparticles exposure on germinating wheat seedlings

We investigated the effects of 1 and 10 mg L(-1) AgNPs on germinating Triticum aestivum L. seedlings. The exposure to 10 mg L(-1) AgNPs adversely affected the seedling growth and induced morphological modifications in root tip cells. TEM analysis suggests that the observed effects were due primarily to the release of Ag ions from AgNPs. To gain an increased understanding of the molecular response to AgNP exposure, we analyzed the genomic and proteomic changes induced by AgNPs in wheat seedlings. At the DNA level, we applied the AFLP technique and we found that both treatments did not induce any significant DNA polymorphisms. 2DE profiling of roots and shoots treated with 10 mg L(-1) of AgNPs revealed an altered expression of several proteins mainly involved in primary metabolism and cell defense.

A DNA Barcoding Approach to Characterize Pollen Collected by Honeybees

In the present study, we investigated DNA barcoding effectiveness to characterize honeybee pollen pellets, a food supplement largely used for human nutrition due to its therapeutic properties. We collected pollen pellets using modified beehives placed in three zones within an alpine protected area (Grigna Settentrionale Regional Park, Italy). A DNA barcoding reference database, including rbcL and trnH-psbA sequences from 693 plant species (104 sequenced in this study) was assembled. The database was used to identify pollen collected from the hives. Fifty-two plant species were identified at the molecular level. Results suggested rbcL alone could not distinguish among congeneric plants; however, psbA-trnH identified most of the pollen samples at the species level. Substantial variability in pollen composition was observed between the highest elevation locality (Alpe Moconodeno), characterized by arid grasslands and a rocky substrate, and the other two sites (Cornisella and Ortanella) at lower altitudes. Pollen from Ortanella and Cornisella showed the presence of typical deciduous forest species; however in samples collected at Ortanella, pollen of the invasive Lonicera japonica, and the ornamental Pelargonium x hortorum were observed. Our results indicated pollen composition was largely influenced by floristic local biodiversity, plant phenology, and the presence of alien flowering species. Therefore, pollen molecular characterization based on DNA barcoding might serve useful to beekeepers in obtaining honeybee products with specific nutritional or therapeutic characteristics desired by food market demands.

DNA Barcoding as an Effective Tool in Improving a Digital Plant Identification System: A Case Study for the Area of Mt. Valerio, Trieste (NE Italy)

Background Identification keys are decision trees which require the observation of one or more morphological characters of an organism at each step of the process. While modern digital keys can overcome several constraints of classical paper-printed keys, their performance is not error-free. Moreover, identification cannot be always achieved when a specimen lacks some morphological features (i.e. because of season, incomplete development or miss-collecting). DNA barcoding was proven to have great potential in plant identification, while it can be ineffective with some closely related taxa, in which the relatively brief evolutionary distance did not produce differences in the core-barcode sequences. Methodology/Principal Findings In this paper, we investigated how the DNA barcoding can support the modern digital approaches to the identification of organisms, using as a case study a local flora, that of Mt. Valerio, a small hill near the centre of Trieste (NE Italy). The core barcode markers (plastidial rbcL and matK), plus the additional trnH-psbA region, were used to identify vascular plants specimens. The usefulness of DNA barcoding data in enhancing the performance of a digital identification key was tested on three independent simulated scenarios. Conclusions/Significance Our results show that the core barcode markers univocally identify most species of our local flora (96%). The trnH-psbA data improve the discriminating power of DNA barcoding among closely related plant taxa. In the multiparametric digital key, DNA barcoding data improves the identification success rate; in our simulation, DNA data overcame the absence of some morphological features, reaching a correct identification for 100% of the species. FRIDA, the software used to generate the digital key, has the potential to combine different data sources: we propose to use this feature to include molecular data as well, creating an integrated identification system for plant biodiversity surveys.

A rapid diagnostic approach to identify poisonous plants using DNA barcoding data

Among plants, several groups have toxicities that are dangerous for humans. Plant exposures are indeed one of the most frequent cases reported to poison control centers. A rapid and easy screening test is required for accurate medical treatment. However, it is usually based on the morphological analysis of ingested plant portions that is expensive in terms of time and resources requiring experience in systematic botany which could also be biased by the absence of clear diagnostic traits in stomach contents. In this study, we designed specific primer pairs for the amplification of a sequence-characterized amplified region within standard barcode regions (i.e., rbcL and trnH–psbA) to detect toxic plants belonging to the genera Atropa and Colchicum. Allied edible species were also included in our data-set to exclude the cross-amplification with the toxic ones when the detection system is applied. Using real-time polymerase chain reaction, we tested the specificity of the selected primer pairs in order to develop a fast and reliable tool to be used in poison centers.

Lamyropsis genus in the Mediterranean area: phylogenetic position of L. microcephala (Asteraceae: Cardueae)

The aim of this study was to give results about position of Lamyropsis microcephala within an already existing phylogeny of Lamyropsis genus on the Mediterranean area, by analyzing external transcribed spacer/internal transcribed spacer sequence data. The four Lamyropsis species considered in the model can be recognized as distinct taxa originated from successive migration/speciation events.

Genetic variability of the first-generation of Ribes sardoum, a threatened relic plant requiring translocation measures

Abstract The genetic variability of the ex situ cultivated plants of Ribes sardoum, obtained from seeds collected from the unique natural population, was investigated. Our results revealed that plants cultivated ex situ captured a higher amount of genetic diversity and this will be useful in future translocation of this threatened species.

Valorizing coffee pulp by-products as anti-inflammatory ingredient of food supplements acting on IL-8 release

Coffee is the second traded food commodity in the world. Beyond roasted seeds, the most part of the original fruit -and in particular pulp- is discarded as waste, with severe environmental and economic consequences in many developing countries. Our research focused on developing an eco-friendly extraction protocol of phytocomplexes from coffee pulp and evaluating their bioactivity and beneficial effects to human health as food supplements. Antioxidant activity assays (Folin-Ciocalteu and DPPH assays) were adopted to select the most effective extraction technique and results show antioxidant activity of coffee pulp extracts. After analysis of cytotoxicity on human epithelial gastric cells, measurements of IL-8 release of treated or pre-treated cells were performed. Results showed that the use of soft technical equipment and sustainable solvents (i.e. maceration process, aqueous extraction) can extract phytocomplexes with antioxidant properties. Moreover, IL-8 measurements showed impairment of this chemokine release at concentrations that may be reached in vivo in the gastrointestinal tract, following consumption of reasonable amount of extract. Pre-treatments analysis demonstrated the ability of coffee pulp extracts to prevent IL-8 release by gastric epithelial cells. Chemical evaluation performed by liquid chromatography mass spectrometry showed that quinic acid derivatives are abundant in coffee pulp extract together with procyanidins derivatives: those compounds might be responsible for the high biological activity. This evidence supports future applications of coffee pulp extracts as food supplement with high added value, starting from a waste that can be valorized through simple yet efficient extraction methods.