Plant Secondary Metabolites: An Opportunity for Circular Economy

Moving toward a more sustainable development, a pivotal role is played by circular economy and a smarter waste management. Industrial wastes from plants offer a wide spectrum of possibilities for their valorization, still being enriched in high added-value molecules, such as secondary metabolites (SMs). The current review provides an overview of the most common SM classes (chemical structures, classification, biological activities) present in different plant waste/by-products and their potential use in various fields. A bibliographic survey was carried out, taking into account 99 research articles (from 2006 to 2020), summarizing all the information about waste type, its plant source, industrial sector of provenience, contained SMs, reported bioactivities, and proposals for its valorization. This survey highlighted that a great deal of the current publications are focused on the exploitation of plant wastes in human healthcare and food (including cosmetic, pharmaceutical, nutraceutical and food additives). However, as summarized in this review, plant SMs also possess an enormous potential for further uses. Accordingly, an increasing number of investigations on neglected plant matrices and their use in areas such as veterinary science or agriculture are expected, considering also the need to implement "greener" practices in the latter sector

Potential use in the treatment of inflammatory disorders and obesity of selected wild edible plants from Calabria region (Southern Italy)

Abstract The potential role of plants and their metabolites has been recently considered in the search for new well-tolerated anti-arthritic and anti-obesity drugs. This study was designed to assess the potential effectiveness of the methanolic extracts from four wild edible species from Southern Italy, Asparagus officinalis L., Bellis perennis L., Daucus carota L. and Sambucus nigra L. All these plants have a history as anti-rheumatic or anti-arthritic remedies. The chemical constituents were identified through GC–MS and HPTLC analyses and the in vitro antioxidant activity was determined by means of DPPH, ABTS, FRAP-Ferrozine and β-carotene bleaching tests. To assess the anti-inflammatory and anti-arthritic potentials, the capacity to inhibit nitric oxide production in murine macrophage RAW 264.7 cells and protein denaturation was measured. The anti-obesity potential was determined by evaluating the ability of the sample to inhibit pancreatic lipase, a key enzyme for dietary fats absorption. The raw extract of D. carota showed the best inhibitory activity on NO production (IC50 = 45.1 ± 1.0 μg/mL), followed by B. perennis and A. officinalis (IC50 equal to 193.1 ± 3.2 μg/mL and 506.3 ± 5.1 μg/mL, respectively). D. carota induced also inhibitory effects against the heat-induced denaturation of bovine serum albumin (IC50 = 878.7 ± 19.09 μg/mL) and the best lipase inhibitory potential (IC50 = 1.63 ± 0.07 mg/mL). Our findings suggest that this species could be a potential effective therapeutic agent to treat inflammation and arthritis, supporting the traditional popular use of this plant

Extracţia fenolilor şi flavonoidelor din specia Centaurea CyanuS L

Obiectivul prezentei lucrări a fost de a obţine extracte polifenolice din Centaurea cyanus L. În vederea optimizării condiţiilor extracţiei s-au analizat parametrii care pot influenţa procesul: tipul şi concentraţia solventului (etanol 60 şi 80%), produsul vegetal, perioada de colectare a produsului vegetal, numărul extracţiilor. S-a demonstrat că totalul compuşilor fenolici şi flavonoidelor este maximum în extractul hidroalcoolic 60% (350.91 mgGAE/g şi 274.28 mg rutozidă/g masă uscată, respectiv), obţinut din părţi aeriene colectate la începutul înfloririi

Metabolomic analysis and bioactivities of Arbutus unedo leaves harvested across the seasons in different natural habitats of Sardinia (Italy)

Background: Arbutus unedo L. is a wild tree of Mediterranean regions used as food and in traditional medicine and important for afforestation programs. There is no detailed information available on the variation of A. unedo leaves metabolome across the seasons. The leaves were analyzed by Proton nuclear magnetic resonance (1 H NMR)-based metabolomics, comparing samples harvested across the seasons and in ten different natural habitats of Sardinia (Italy). Results: Multivariate analysis showed the impact of seasonal variation on the metabolome: glucose and quinic acid increased in summer, while in spring sucrose was accumulated. β-Arbutin, the main known active principle of A. unedo, generally reached the highest concentration in autumn. In winter, O-β-methylglucose, γ-aminobutyric acid (GABA), flavonols (quercetin-3-O-α-rhamnoside, myricetin-3-O-α-rhamnoside, kaempferol-3-O-α-rhamnoside), catechin, and gallocatechin increased. Characteristic metabolomic features were found also for samples collected in different locations. For instance, trees growing at the highest altitude and exposed to lower temperatures produced less flavonols and catechins. The only sample collected on trees growing on limestones, dolomites, and dolomitic limestones type of soil showed generally the highest content of arbutin. The highest phenolics content was found during spring, while samples collected on flowering branches in winter were the ones with the highest flavonoid content. The antioxidant activity was also variated, ranging from 1.3 to 10.1 mg of Trolox equivalents (TE)/mL of extract, and it was positively correlated to both total phenolics and flavonoid content. Winter samples showed the lowest antibacterial activity, while summer and autumn ones exhibited the highest activity (IC50 values ranging from 17.3 to 42.3 µg/mL against Staphylococcal species). Conclusion: This work provides 1 H-NMR fingerprinting of A. unedo leaves, elucidating the main metabolites and their variations during seasons. On the basis of arbutin content, autumn could be considered the balsamic period of this taxon. Samples collected in this season were also the most active ones as antibacterial. Moreover, an interesting metabolomic profile enriched in catechins and flavonols was observed in leaves collected in winter on flowering branches which were endowed with high antioxidant potential

Berberine and Tinospora cordifolia exert a potential anticancer effect on colon cancer cells by acting on specific pathways

Berberine (BBR) is a natural active principle with potential antitumor activity. The compound targets multiple cell signaling pathways, including proliferation, differentiation, and epithelial-mesenchymal transition. The aim of this study was to elucidate the mechanisms behind the anticancer activity of BBR by comparing the effects of purified BBR with those of the extract of Tinospora cordifolia, a medicinal plant that produces this metabolite. The expression levels of a panel of 44 selected genes in human colon adenocarcinoma (HCA-7) cell line were quantified by real-time polymerase chain reaction (PCR). BBR treatment resulted in a time- and dose-dependent down regulation of 33 genes differently involved in cell cycle, differentiation, and epithelial-mesenchymal transition. The trend was confirmed across the two types of treatment, the two time points, and the different absolute dosage of BBR. These findings suggest that the presence of BBR in T. cordifolia extract significantly contributes to its antiproliferative activity

Metabolomics and genetics of reproductive bud development in Ficus carica var. sativa (edible fig) and in Ficus carica var. caprificus (caprifig): similarities and differences

In figs, reproductive biology comprises cultivars requiring or not pollination, with female trees (edible fig) and male trees (caprifig) bearing different types of fruits. Metabolomic and genetic studies may clarify bud differentiation mechanisms behind the different fruits. We used a targeted metabolomic analysis and genetic investigation through RNA sequence and candidate gene investigation to perform a deep analysis of buds of two fig cultivars, ‘Petrelli’ (San Pedro type) and ‘Dottato’ (Common type), and one caprifig. In this work, proton nuclear magnetic resonance (1H NMR-based metabolomics) has been used to analyze and compare buds of the caprifig and the two fig cultivars collected at different times of the season. Metabolomic data of buds collected on the caprifig, ‘Petrelli’, and ‘Dottato’ were treated individually, building three separate orthogonal partial least squared (OPLS) models, using the “y” variable as the sampling time to allow the identification of the correlations among metabolomic profiles of buds. The sampling times revealed different patterns between caprifig and the two edible fig cultivars. A significant amount of glucose and fructose was found in ‘Petrelli’, differently from ‘Dottato’, in the buds in June, suggesting that these sugars not only are used by the ripening brebas of ‘Petrelli’ but also are directed toward the developing buds on the current year shoot for either a main crop (fruit in the current season) or a breba (fruit in the successive season). Genetic characterization through the RNA-seq of buds and comparison with the literature allowed the identification of 473 downregulated genes, with 22 only in profichi, and 391 upregulated genes, with 21 only in mammoni

Supporting Material for: "NMR-based metabolomics for frauds detection and quality control of oregano samples"

Table S1. Summary of NMR experiments performed in order to elucidate the structure of salvianolic acid B. Sample was solubilized in CD3OD. Fig. S1 1H NMR spectrum obtained for apigenin (in fraction 114) solubilized in CD3OD. Fig. S2. 1H NMR spectrum obtained for rosmarinic acid (found in EtOAc fraction from Oregano vulgare) solubilized in CD3OD. Fig. S3 1H NMR spectrum obtained for thymol, and p-cymene (found in CHCl3 fraction from Oregano onites) solubilized in CD3OD. Fig. S4 1H NMR spectrum of salvianolic acid B solubilized in CD3OD. Fig. S5 NMR COSY spectrum of salvianolic acid B solubilized in CD3OD. Fig. S6 NMR HSQC spectrum of salvianolic acid B solubilized in CD3OD. Fig. S7 NMR HMBC spectrum of salvianolic acid B solubilized in CD3OD. Fig. S8 NMR J-res spectrum of salvianolic acid B solubilized in CD3OD. Fig. S9 A) S-plot from OPLS-DA model showing the most important spectral bins for the discrimination between the two commercial species of oregano. B) Result of the permutation test of the OPLS-DA model. C) Loading column plot from OPLS-DA model. Fig. S10 Main biomarkers found in this work. Fig. S11. PCA score scatter plot where unknown species (green dots) are distinguished from marketable oregano and placed as outliers by the model. Fig. S12 Extended regions of observed vs predicted plots from OPLS models (y = % of total impurity) of A) Origanum vulgare B) Origanum onites. Fig. S13 Graphic obtained by permutation test of the OPLS model built using as y variable the % of cistus contamination. Fig. S14 J-res spectra of Oregano contaminated with cistus (A) and pure oregano (B). The contaminated sample presents a singlet at δ 3.57.Supplementary material for: Mandrone, M., Marincich, L., Chiocchio, I., Petroli, A., Gođevac, D., Maresca, I.,& Poli, F. (2021). NMR-based metabolomics for frauds detection and quality control of oregano samples. Food Control, Elsevier., 127, 108141. [https://doi.org/10.1016/j.foodcont.2021.108141]Published version of the manuscript: [https://cer.ihtm.bg.ac.rs/handle/123456789/4550]The peer-reviewed version: [https://cer.ihtm.bg.ac.rs/handle/123456789/4577

Arbutus unedo L. Fractions Exhibit Chemotherapeutic Properties for the Treatment of Gastrointestinal Stromal Tumors

Novel treatments in gastrointestinal stromal tumors (GISTs) are essential due to imatinib resistance and the modest results obtained with multi-target tyrosine kinase inhibitors. We investigated the possibility that the hydroalcoholic extract from the leaves of Arbutus unedo L. (AUN) could harbor novel chemotherapeutics. The bio-guided fractionation of AUN led to a subfraction, FR2-A, that affected the viability of both imatinib-sensitive and -resistant GIST cells. Cells treated with FR2-A were positive for Annexin V staining, a marker of apoptosis. A rapid PARP-1 downregulation was observed, although without the traditional caspase-dependent cleavage. The fractionation of FR2-A produced nine further active subfractions (FRs), indicating that different molecules contributed to the effect promoted by FR2-A. NMR analysis revealed that pyrogallol-bearing compounds, such as gallic acid, gallic acid hexoside, gallocatechin, myricetin hexoside, and trigalloyl-glucose, are the main components of active FRs. Notably, FRs similarly impaired the viability of GIST cells and peripheral blood mononuclear cells (PBMCs), suggesting a non-specific mechanism of action. Nevertheless, despite the lack of specificity, the established FRs showed promising chemotherapeutic properties to broadly affect the viability of GIST cells, including those that are imatinib-resistant, encouraging further studies to investigate whether pyrogallol-bearing compounds could represent an alternative avenue in GISTs

Isolation, absolute configuration and cytotoxic activities of alkaloids from Hippeastrum goianum (Ravenna) Meerow (Amaryllidaceae)

The phytochemical study of Hippeastrum goianum led to the identification of 13 compounds by means of gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). Compounds 7-demethoxy-9-O-methylhostasine (1) and 7-deoxi-trans-dihydronarciclasine (2) had their absolute configurations determined by vibrational circular dichroism (VCD). This is the first time that compound 1 is described in the Amaryllidaceae family. The cytotoxicity of all isolated compounds was tested against colorectal carcinoma (HCT 116), breast carcinoma (MCF-7), and non-tumor human retinal pigment epithelium (RPE) cell lines. The half-maximum inhibitory concentration (IC50) of compound 2 against each cell line was equivalent to the positive control (doxorubicin), indicating a considerable cytotoxic activity. Keywords: narciclasine; galasine; cytotoxic activity; absolute configuration; vibrational circular dichrois