Chiara Toniolo

Hypericum perforatum: Influences of the habitat on chemical composition, photo-induced cytotoxicity, and antiradical activity.

Abstract Context: Hypericin, isolated from Hypericum perforatum L. and about another 300 Hypericum species (Guttiferae), is one of the most powerful photosensitizers found in nature. Objective: The aim of this study was to assess the variability of chemical composition and biological activities of four H. perforatum samples, collected at different altitudes in the South Apennine of Italy. Materials and methods: MTT assay was used to evaluate the antiproliferative activity of different samples concentrations (0.6–100 µg/mL) after irradiation at 365 nm. The inhibition of nitric oxide production was evaluated after 24 h of incubation using the macrophage cell line RAW 264.7 and sample solutions ranging from 12.5 to 1000 µg/mL. Antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and β-carotene bleaching test (ranges were 12.5–1000 and 1–400 µg/mL, respectively). Chemical composition was evaluated through HPTLC, and different contents of hypericin and rutin have been observed. Results: The most phototoxic sample was collected from Zumpano (no. 1 at 370 m), with IC50 values of 24.61 ± 0.02 μg/mL. Sample no. 1 showed also the best radical scavenging activity (IC50 value of 9.18 ± 0.03 μg/mL) and the best antioxidant activity (IC50 value of 10.04 ± 0.03 μg/mL after 30 min of incubation). Best activity of extract no. 1 was well in accordance with chemical data, including the phenolic total content and particular metabolome profile. Discussion and conclusion: This paper confirms the usefulness in maintaining the exploration of H. perforatum activities, in order to confirm its potentiality as a multipurpose plant.

Neem (Azadirachta indica): towards the ideal insecticide?

Abstract Pesticide resistance is going to change rapidly our antibiotics and insecticides arsenal. In this scenario, plant-derived natural products are considered valuable candidates to reverse this negative trend. Growing research attention is focused on neem (Azadirachta indica, Meliaceae), exploring the utility of its products as insecticides and antibiotics. In this review, we summarised the knowledge on neem oil and neem cake by-products in arthropod pest control, with special reference to mosquito vectors of public health importance. To the best of our knowledge, neem-borne products currently showed effective and eco-friendly features, including little non-target effects, multiple mechanisms of action, low cost, easy production in countries with limited industrial facilities. In particular, the potentiality of neem cake as ideal and affordable source of mosquitocidal compounds in anopheline and aedine control programmes is outlined. Overall, we propose the employ of neem-based products as an advantageous alternative to build newer and safer arthropod control tools.

Traceability in Multi-Ingredient Botanicals by HPTLC Fingerprint Approach

A high-performance thin-layer chromatography (HPTLC) method was developed for simple and rapid chemical analyses of multi-ingredient botanicals. The method was based on comparison of the fingerprint of the marketed multi-ingredient botanical with the fingerprints of the extracts of its component plants and of a handmade mixture of the constituent extracts in a ratio as similar as possible to that of the market product, when labeled. Planar chromatography analysis was completed by a densitometric scansion. The analyses revealed a good correspondence between the market products and the handmade mixture of standard extracts.

HPTLC determination of chemical composition variability in raw materials used in botanicals

Besides the chemotaxonomic value, nowadays determination of biodiversity and chemical variability has a commercial impact. The exact identity of raw material and constituents of botanical products, such as food supplements or herbal remedies, is a very important argument, being the real prerequisite for quality control and traceability, followed by the determination of active components. However, the analytical approach must consider the natural great variability in secondary metabolites and product form, such as in extracts. Against the reductive approach, on the basis of single chemical standards, so far dominant in Pharmacopoeias monographs, we report applications and utility of the high-performance thin-layer chromatography fingerprint in determination of species of the same genus, of populations of the same species and of different drugs of the same plant.

Bluetongue outbreaks: Looking for effective control strategies against Culicoides vectors.

Several arthropod-borne diseases are now rising with increasing impact and risks for public health, due to environmental changes and resistance to pesticides currently marketed. In addition to community surveillance programs and a careful management of herds, a next-generation of effective products is urgently needed to control the spread of these diseases, with special reference to arboviral ones. Natural product research can afford alternative solutions. Recently, a re-emerging of bluetongue disease is ongoing in Italy. Bluetongue is a viral disease that affects ruminants and is spread through the bite of bloodsucking insects, especially Culicoides species. In this review, we focused on the importance of vector control programs for prevention or bluetongue outbreaks, outlining the lack of effective tools in the fight against Culicoides vectors. Then, we analyzed a field case study in Sardinia (Italy) concerning the utilization of the neem cake (Azadirachta indica), to control young instar populations of Culicoides biting midges, the vectors of bluetongue virus. Neem cake is a cheap and eco-friendly by-product obtained from the extraction of neem oil. Overall, we propose that the employ of neem extraction by-products as aqueous formulations in muddy sites close to livestock grazing areas may represent an effective tool in the fight against the spread of bluetongue virus in the Mediterranean areas.

Nutritional composition, bioactive compounds and volatile profile of cocoa beans from different regions of Cameroon

Abstract Analysis of the complex composition of cocoa beans provides fundamental information for evaluating the quality and nutritional aspects of cocoa-based food products, nutraceuticals and supplements. Cameroon, the world’s fourth largest producer of cocoa, has been defined as “Africa in miniature” because of the variety it habitats. In order to evaluate the nutritional characteristics of cocoa beans from five different regions of Cameroon, we studied their polyphenolic content, volatile compounds and fatty acids composition. The High Performance Thin Layer Chromatography (HPTLC) analysis showed that the Mbalmayo sample had the highest content of theobromine (11.6 mg/g) and caffeic acid (2.1 mg/g), while the Sanchou sample had the highest level of (−)-epicatechin (142.9 mg/g). Concerning fatty acids, the lowest level of stearic acid was found in the Mbalmayo sample while the Bertoua sample showed the highest content of oleic acid. Thus, we confirmed that geographical origin influences the quality and nutritional characteristics of cocoa from these regions of Cameroon.

Ecophysiological and phytochemical response to ozone of wine grape cultivars of Vitis vinifera L.

Abstract Vitis vinifera sensitivity to tropospheric ozone (O3) has been evidenced in several studies. In this work, physiological and metabolic effects of O3 on two wine cultivars of V. vinifera (i.e. Maturano and San Giuseppe) have been studied. Moreover, chlorogenic acid (CGA) production, in consideration of its importance in the biosynthetic pathway of polyphenols and as antioxidant, has been investigated. Maturano cultivar resulted more sensitive to O3, as evidenced by the gas exchange reduction at the early stage of treatment, and by the increase in Ci/Ca and the decoupling of net photosynthesis and the stomatal conductance at the end of the treatment. Unexpectedly, O3 did not activate stilbene production. Ozone induced an early CGA decrease, significantly more consistent in cv. Maturano, and an increase after 8 days, more consistent in cv. S. Giuseppe. These results suggest that CGA could be considered a biochemical marker of O3-induced stress in V. vinifera.

Sisymbrium Officinale (L.) Scop. and its Polyphenolic Fractions Inhibit the Mutagenicity of Tert-Butylhydroperoxide in Escherichia Coli WP2uvrAR Strain.

One Sisymbrium officinale (L.) Scop. aqueous dry extract (SOE) and its polyphenolic fractions (Fb, Fc, Fd and Fe) were evaluated for their ability to inhibit the oxidative mutagenicity of tert‐butylhydroperoxide in the Ames test. The possible involvement of desmutagenic and/or bioantimutagenic mechanisms was evaluated by applying a three‐time based protocol (pre‐treatment, co‐treatment and post‐treatment). Furthermore, some protective antioxidant mechanisms were investigated. The total polyphenol and flavonol amount was also determined, and the fingerprint was outlined by high‐performance thin‐layer chromatography and densitometry. SOE, Fb and Fe exhibited strong antimutagenicity against tert‐butylhydroperoxide in all treatment protocols, this suggesting the involvement of both desmutagenic and bioantimutagenic mechanisms. These samples also showed antioxidant properties, including neutralization of the superoxide anion, lipid peroxidation inhibition and chelation and reduction of iron. Fb and Fe were rich in polyphenols and flavonols, so suggesting a possible role of these compounds in the antimutagenicity. Taking into account that oxidative stress is responsible for the damage of various environmental toxicants, particularly tobacco smoke, present results can support the traditional use of hedge mustard by smokers to restore the vocal cord function affected by the oxidative damage and suggest a possible application of SOE and its fractions as food supplements. Copyright

Antioxidant activity and chemical composition of three Tunisian Cistus: Cistus monspeliensis, Cistus villosus and Cistus libanotis.

The chemical composition of three rockrose Cistus species, Cistus monspeliensis, Cistus libanotis and Cistus villosus, collected in Tunisia, was studied by HPTLC, focusing on the terpenes and phenols constituents. Diterpenes of Cistus are important as the main constituents of the leaf sticky aromatic resin, known as labdanum, which are highly appreciated in perfumery. Polyphenols in the methanolic extracts of each species were identified, quantified as total and as flavonoids and tannins, and tested for antioxidant activity. Diterpenes were evident in C. libanotis and C. monspeliensis, whereas they were practically absent in C. villosus; C. libanotis had higher phenolic amount, whereas antioxidant activities were important, but different according to the following tests: DPPH radical scavenging, conversion of the Fe3+/ferricyanide complex and inhibition of β-carotene bleaching. The reported data confirm the validity of utilisation of Cistus sp. in marketed herbal products, as well as the relevant presence of diterpenes in species actually not used for labdanum production.

A new problem. Contamination of botanicals by phthalates. Rapid detection tests

The purity of solvents used in medical, herbal and food products is an essential prerequisite. This communication is focused on the possible occurrence of phthalates contaminant derived from the utilisation of plastic containers for solvents instead of glass containers. The contamination must be detected also in the derived marketed extracts, like botanical food supplements.