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

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

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

Design and Characterization of an Ethosomal Gel Encapsulating Rosehip Extract

© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Rising environmental awareness drives green consumers to purchase sustainable cosmetics based on natural bioactive compounds. The aim of this study was to deliver Rosa canina L. extract as a botanical ingredient in an anti-aging gel using an eco-friendly approach. Rosehip extract was first characterized in terms of its antioxidant activity through a DPPH assay and ROS reduction test and then encapsulated in ethosomal vesicles with different percentages of ethanol. All formulations were characterized in terms of size, polydispersity, zeta potential, and entrapment efficiency. Release and skin penetration/permeation data were obtained through in vitro studies, and cell viability was assessed using an MTT assay on WS1 fibroblasts. Finally, ethosomes were incorporated in hyaluronic gels (1% or 2% w/v) to facilitate skin application, and rheological properties were studied. Rosehip extract (1 mg/mL) revealed a high antioxidant activity and was successfully encapsulated in ethosomes containing 30% ethanol, having small sizes (225.4 ± 7.0 nm), low polydispersity (0.26 ± 0.02), and good entrapment efficiency (93.41 ± 5.30%). This formulation incorporated in a hyaluronic gel 1% w/v showed an optimal pH for skin application (5.6 ± 0.2), good spreadability, and stability over 60 days at 4 °C. Considering sustainable ingredients and eco-friendly manufacturing technology, the ethosomal gel of rosehip extract could be an innovative and green anti-aging skincare product.The authors are thankful to Sofia Melo Rocha for her contribution to the work. The authors thank the Fundação para a Ciência e Tecnologia, Portugal (UIDB/04138/2020 and UIDP/04138/2020 for iMed.ULisboa, CEECINST/00145/2018 for J. Marto, and CEEC-IND/03143/2017 for L. M. Gonçalves).info:eu-repo/semantics/publishedVersio

Natural product chemistry and metabolomics: a roadmap through circular economy, sustainable agriculture, and biodiversity valorization

Inspired by the Sustainable Developmental Goals of the Agenda 2030, this work addressed three topics of pivotal importance in the sustainability era, namely: circular economy, sustainable agriculture, and biodiversity valorization. Natural products chemistry and metabolomics were keys to achieve the following aims: 1) the valorization of waste plant material for circular economy, 2) the achievement of deep knowledge of plant-environment interactions in view of sustainable agriculture, 3) the biodiversity valorization through the investigation of local flora. The first aim was accomplished by analyzing the phytochemical profile and the bioactivity of neglected plants matrices. Residues of aromatic plants after distillation resulted active against a plant pathogen suggesting a potential reuse of these matrices in agriculture. In addition, by-products of chestnut cultivation proved endowed with in vitro neuroprotective properties. The second aim was achieved by the development of two case studies. In particular, a work was carried out in field to study Sorghum bicolor subjected to several environmental and anthropic factors, and the other one in greenhouse exploring Taxus baccata responses to different LED lighting. Metabolomics proved successful to identify sorghum biomarkers for crop quality and development and allowed to monitor taxus growth providing useful insights for sustainable agriculture. To achieve the third aim, spontaneous plants collected in Sardinia were investigated for their antiproliferative activities. Five plants resulted endowed with promising bioactivity thus their phytochemical composition was investigated through NMR spectroscopy. Finally, a focus on chemodiversity was placed by studying Solanum dulcamara chemotypes through MS metabolomics which revealed that the chemotypes differed for the leaf steroidal glycoalkaloids. The overall thesis work underlined the importance of plant specialized metabolites in multiple fields and demonstrated that the study of these molecules aids the sustainable development, enhancing circular economy, sustainable agriculture, and biodiversity valorization. In this context, metabolomics approach resulted particularly interesting

Phytochemical Profile and In Vitro Bioactivities of Plant-Based By-Products in View of a Potential Reuse and Valorization

Wastes and by-products of plant origin are of particular interest to develop a circular economy approach, which attempts to turn them into resources. In this work, thirty-seven neglected plant matrices, including agricultural residues, pest plants, and by-products from the herbal and food industry were extracted and tested for their in vitro anti-tyrosinase, antioxidant, and antibacterial activity against the phytopathogens Pseudomonas syringae pv. syringae ATCC 19310 and Clavibacter michiganensis subsp. nebraskense ATCC 27822. Antioxidant activity ranged from 0.3 to 5 mg of Tr. eq/mL of plant extract, and extract of Castanea sativa pericarp (Csp), Rosa damascena buds (post-distillation) (Rod), and Prunus amygdalus exocarp and mesocarp (Pam) were the most powerful ones. Csp was also capable of inhibiting tyrosinase (IC50 = 16.5 µg/mL), as well as three distillation by-products, namely: Cupressus sempervirens (Css) (IC50 = 95.5 µg/mL), Salvia officinalis (Sco) (IC50 = 87.6 µg/mL), and Helichrysum italicum (Hei) (IC50 = 90.1 µg/mL). Five residues from distillation showed antibacterial activity against C. michiganensis (MICs ranging from 0.125 to 1 mg/mL), namely: Salvia sclarea L. (Sas), Salvia rosmarinus Schleid (Sar), Sco, Hei, and Css. The 1H NMR fingerprinting of the bioactive matrices was acquired, detecting primary and secondary metabolites (rosmarinic acid, shikimic acid, sclareol, and hydroxycinnamic acids)

Wound healing and in vitro antiradical activity of five Sedum species grown within two sites of community importance in Emilia-Romagna (Italy)

Sedum genus includes more than 400 different species, many of which having ethnobotany interest. The skin healing is one of the most common therapeutic indication of Sedum spp. In this work, for the first time, we compared five different Sedum species grown in two sites of community importance in Emilia Romagna (Italy): Sedum acre L., Sedum album L., Sedum hispanicum L., Sedum rupestre L. and Sedum sexangulare L., analysing their total phenolic and flavonoid content, their antiradical capacity and the in vitro healing activity on human keratinocytes. Total phenolic content of the five species ranged from 35.41 ± 1.18 to 90.22 ± 1.03 µg gallic acid equivalent/mg of dry extract, being S. rupestre the richest one. Total flavonoid content ranged from 22.39 ± 0.51 to 47.93 ± 2.82 µg rutin equivalent/mg of extract and S. album resulted the species with the highest flavonoid content. Antiradical capacity was found to be related to the phenolic content of the extracts. All the extracts were active in wound healing assay and each one showed different kinetic of action and concentration-activity relationship. This study proposes few investigated Sedum species grown in Italy as promising agents for skin healing and suggests further phytochemical and biological investigations

Metabolomic Study of Sorghum (Sorghum bicolor) to Interpret Plant Behavior under Variable Field Conditions in View of Smart Agriculture Applications

To tackle the urgency of smarter crop management, the complex nature of agricultural ecosystems needs to be better understood, employing and combining different techniques and technologies. In this study, untargeted metabolomics and agro-meteorological survey were coupled to study the variation of Sorghum bicolor (L.) Moench metabolome during crop development, in response to environmental and anthropic factors. Twelve crop fields in the Emilia-Romagna region, Italy, were monitored and sampled at different stages, seedling (Ss), advanced vegetative (Sv), and ripening (Sr), and subjected to 1H NMR-based metabolomics. The analytical method developed resulted to be successful to quickly analyze different sorghum organs. Dhurrin, a cyanogenic glucoside, resulted to be a biomarker of crop quality and development, and several insights into its turnover and functions were obtained. In particular, p-glucosyloxy-2-hydroxyphenylacetic acid was identified, for the first time, as the main metabolite accumulated in sorghum at Sr, after gradual dhurrin neutralization. During plant life, fertilization and biotic and abiotic stress reflected peculiar metabolomic profiles. Water supply and soil features (i.e., clay content) were correlated to metabolomic variations, affecting dhurrin (and related metabolites), amino acids, organic acids, and carbohydrate content. Increase in chlorogenic acid was registered in consequence of predator attacks. Moreover, grain from three fields presented traces of dhurrin and the lowest antioxidant potential, which resulted in poor grain quality. Metabolomics turned out to be a promising tool in view of smart agriculture for monitoring plant growth status and applying appropriate agricultural practices since the early stage of crop development