Phytochemical composition and bioactive potential of Melissa officinalis L., Salvia officinalis L. and Mentha spicata L. extracts

Plants are rich in bioactive phytochemicals that often display medicinal properties. These can play an important role in the production of health-promoting food additives and the replacement of artificial ones. In this sense, this study aimed to characterise the polyphenolic profile and bioactive properties of the decoctions, infusions and hydroethanolic extracts of three plants: lemon balm (Melissa officinalis L.), sage (Salvia officinalis L.) and spearmint (Mentha spicata L.). Total phenolic content ranged from 38.79 mg/g extract to 84.51 mg/g extract, depending on the extract. The main phenolic compound detected in all cases was rosmarinic acid. The results highlighted that some of these extracts may have the ability to prevent food spoilage (due to antibacterial and antifungal effects) and promote health benefits (due to anti-inflammatory and antioxidant capacities) while not displaying toxicity against healthy cells. Furthermore, although no anti-inflammatory capacity was observed from sage extracts, these stood out for often displaying the best outcomes in terms of other bioactivities. Overall, the results of our research provide insight into the potential of plant extracts as a source of active phytochemicals and as natural food additives. They also support the current trends in the food industry of replacing synthetic additives and developing foods with added beneficial health effects beyond basic nutrition.info:eu-repo/semantics/publishedVersio

By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties

[EN] Opuntia spp. are a tropical and subtropical plant that provides both edible green steams and fruits; however, the processing of this fruits results in the accumulation of enormous amount of by-products that can be a source of bioactive and pigmented compounds. Herein, three cactus pear from the species Opuntia focus-indica var. sanguigna (OS) and gialla (OG) and Opuntia engelmannii (OE) were fully characterized regarding their phenolic and betalain composition and correlated with their antioxidant and antimicrobial activities. The hydroethanolic extracts of OE gave the highest amount of phenolic compounds isorhamentin-O-(deoxyhexosyl-hexoside) and betacianins (betanin); however, no betaxanthins were identified in this sample. This sample also revealed the lowest EC50 values in all the antioxidant activity assays. Regarding antimicrobial activity, the hydroethanolic extracts of all species revealed to be more active than ampicillin. The pivotal objective of this work was to focus on exploring by-product biocompounds and possible outputs, thus, we could suggest the use of these natural colorants with intrinsic antioxidant and antimicrobial activity, which would grant industries to produce cleaner label products with functional benefits.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. This work is funded by the European Structural and Investment Funds (FEEI) through the Regional Operational Program North 2020, within the scope of Project NORTE-01-0145-FEDER-023289 (DeCodE) and ValorNatural (R). B. Melgar (No. 329930) also thanks CONACyT for his grant. The authors are grateful for a grant from the Serbian Ministry of Education, Sciences and Technological Development (no. 173032). The authors would also like to thank Dr. Carlos Aguiar for the botanical identification of these species.Melgar-Castañeda, B.; Dias, MI.; Ciric, A.; Sokovic, M.; Garcia-Castello, EM.; Rodríguez López, AD.; Barros, L.... (2017). By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties. Industrial Crops and Products. 107:353-359. https://doi.org/10.1016/j.indcrop.2017.06.011S35335910

Synthesis of novel methyl 7-[(hetero)arylamino]thieno[2,3-b] pyrazine-6-carboxylates and antitumor activity evaluation: effects in human tumor cells growth, cell cycle analysis, apoptosis and toxicity in non-tumor cells

Several novel methyl 7-[(hetero)arylamino]thieno[2,3-b]pyrazine-6-carboxylates were synthesized by Pd-catalyzed C–N Buchwald–Hartwig cross-coupling of either methyl 7-aminothieno[3,2-b]pyrazine-6-carboxylate with (hetero)arylhalides or 7-bromothieno[2,3-b]pyrazine-6-carboxylate with (hetero)arylamines in good-to-excellent yields (50% quantitative yield), using different reaction conditions, namely ligands and solvents, due to the different electronic character of the substrates. The antitumoral potential of these compounds was evaluated in four human tumor cell lines: gastric adenocarcinoma (AGS), colorectal adenocarcinoma (CaCo-2), breast carcinoma (MCF7), and non-small-cell lung carcinoma (NCI-H460) using the SRB assay, and it was possible to establish some structure–activity relationships. Furthermore, they did not show relevant toxicity against a non-tumor cell line culture from the African green monkey kidney (Vero). The most promising compounds (GI50 ≤ 11 µM), showed some selectivity either against AGS or CaCo-2 cell lines without toxicity at their GI50 values. The effects of the methoxylated compounds 2b (2-OMeC6H4), 2f and 2g (3,4- or 3,5-diOMeC6H3, respectively) on the cell cycle profile and induction of apoptosis were further studied in the AGS cell line. Nevertheless, even for the most active (GI50 = 7.8 µM) and selective compound (2g) against this cell line, it was observed that a huge number of dead cells gave rise to an atypical distribution on the cell cycle profile and that these cells were not apoptotic, which points to a different mechanism of action for the AGS cell growth inhibition.This research was funded by Fundação para a Ciência e Tecnologia (FCT)—Portugal, which financially supports CQUM (UID/QUI/686/2019), and also financed by the European Regional Develop- ment Fund (ERDF), COMPETE2020 and Portugal2020, and the PTNMR network also supported by Portugal2020. J.M.R. PhD grant (SFRH/BD/115844/2016) was financed by FCT, ESF (European Social Fund—North Portugal Regional Operational Program) and HCOP (Human Capital Operational Program). The authors are grateful to FCT, Portugal, for financial support through national funds FCT/MCTES to the CIMO (UIDB/00690/2020). L.B. and R.C.C. thank the national funding by FCT, Portugal, through the institutional scientific employment program-contract for their contracts

Pineapple by-products as a source of bioactive compounds with potential for industrial food application

Pineapple is a tropical fruit consumed fresh or processed into various food products. However, the peel and crown of this fruit are not industrially exploited, thus generating tons of by-products that represent an economic and environmental concern. In order to promote the upcycling of these by-products, this work aimed to characterize the phenolic profile of its hydroethanolic extracts obtained from pineapple peel and crown leaves and to evaluate their in vitro bioactivity. The HPLC-DAD-ESI/MS analysis allowed the identification of 25 phenolic compounds, including phenolic acids and flavonoids. The antioxidant, cytotoxic, and antimicrobial activity assays highlighted the peel extract as the most promising and, therefore, it was incorporated into a traditional Portuguese pastry cake as a functional ingredient. The nutritional parameters of the developed food were not affected by the incorporation of the extract, but it promoted the antioxidant activity during its shelf-life. Overall, pineapple peel and crown appeared as promising by-products to be exploited by the food industry, which can be achieved through a circular economy approach.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). R. C. Calhelha and L. Barros acknowledge the national funding by FCT, P. I., through the institutional scientific employment program-contract, and J. Pinela and M. Carocho through the individual scientific employment program-contract (CEECIND/01011/2018 and CEECIND/00831/2018, respectively). C. Caleja is thankful for her contract through the project Healthy- PETFOOD (POCI-01-0247-FEDER-047073). Conducted under the project “BIOMA – Bioeconomy integrated solutions for the mobilization of the Agro-food market” (POCI-01-0247- FEDER-046112), by “BIOMA” Consortium, and financed by European Regional Development Fund (ERDF), through the Incentive System to Research and Technological development, within the Portugal2020 Competitiveness and Internationalization Operational Program. This work has been supported by the Ministry of Education, Science and Technological Development of Republic of Serbia (451-03-9/ 2021-14/200007).info:eu-repo/semantics/publishedVersio

Evaluation of plant extracts as an efficient source of additives for active food packaging

Natural extracts have been used in several traditional medicine applications and culinary purposes. Their biological properties (antioxidant and antimicrobial) are due to the presence of several active aromatic compounds. Herein, different natural extracts were evaluated, namely structural and thermal characterization and biological activity, in its natural form and incorporated into a polymeric matrix, to assess their effective potential as additives for active food packaging. While rosemary presented the highest thermal stability with a degradation starting at 327°C, lemon balm extract was the less stable (180°C). Regarding the thiobarbituric acid assay, all extracts presented antioxidant activity, in oxidative hemolysis inhibition; anise, cinnamon, and clove extract did not present any action. Overall, the results demonstrated that leaves (rosemary and green tea) and the rhizome (curcumin) are the plant parts with the best performance. Therefore, extracts from aromatic plants are promising natural additives that can be incorporated into polymeric matrices to produce active food packaging film, increasing products shelf-life.The authors acknowledge the financial support by Portugal 2020, and Fundo Social Europeu (FSE) through Programa Operacional Regional do NORTE (NORTE-08-5369–FSE-000034), developed under the program “IMPULSE - Polímeros e Compósitos: Drivers da inovação tecnológica e da competitividade industrial”. To the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional scientific employment program-contract for R. Calhelha, C. Pereira, and L. Barros contracts. This work has also been supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-9/2021-14/ 200007).info:eu-repo/semantics/publishedVersio

Apigenin-7-O-glucoside versus apigenin

Bioactive potential of apigenin derivative apigenin-7-O-glucoside related to its antifungal activity on Candida spp. and cytotoxic effect on colon cancer cells was studied and compared with bioactive potential of apigenin. Antifungal activity was tested on 14 different isolates of Candida spp. using membrane permeability assay, measuring inhibition of reactive oxidative species and inhibition of CYP51 C. albicans enzyme. Cytotoxic potential of apigenin-7-O-glucoside was tested on colon cancer HCT116 cells by measuring cell viability, apoptosis rate and apoptosis- and colon cancer-related gene expression. Obtained results indicated considerable antifungal activity of apigenin-7-O-glucoside towards all Candida isolates. Breakdown of C. albicans plasma membrane was achieved upon treatment with apigenin-7-O-glucoside for shorter period of time then with apigenin. Reduction of intra- and extracellular reactive oxidative species was achieved with minimum inhibitory concentrations of both compounds, suggesting that reactive oxidative species inhibition could be a mechanism of antifungal action. None of the compounds exhibited binding affinity to C. albicans CYP51 protein. Besides, apigenin-7-O-glucoside was more effective compared to apigenin in reduction of cell’s viability and induction of cell death of HCT116 cells. Treatment with both compounds resulted in chromatin condensation, apoptotic bodies formation and apoptotic genes expression in HCT116 cells, but the apigenin-7-O-glucoside required a lower concentration to achieve the same effect. Compounds apigenin-7-O-glucoside and apigenin displayed prominent antifungal potential and cytotoxic effect on HCT116 cells. However, our results showed that apigenin-7-O-glucoside has more potent activity compared to apigenin in all assays that we used

A comparative study of chemical composition, antioxidant and antimicrobial properties of Morchella esculenta (L.) Pers. from Portugal and Serbia

A comparative study on chemical composition (nutritional value, primary and secondary metabolites), antioxidant properties (scavenging activity, reducing power and inhibition of lipid peroxidation), and antimicrobial activity (antibacterial and demelanizing properties) of two samples of Morchella esculenta (morel) from different countries (Portugal and Serbia) was performed. This species was chosen for being one of the most highly prized edible mushrooms in the world. Both samples are rich in carbohydrates (including free sugars) and proteins, and contain several bioactive compounds such as organic acids, phenolic compounds and tocopherols. Polyunsaturated fatty acids were the most abundant compounds followed by mono or saturated fatty acids. Sample from Portugal (SP) gave higher radical scavenging activity and reducing power, while sample from Serbia (SS) showed higher lipid peroxidation inhibition. Both samples gave antibacterial activity against five bacteria (in some cases even better than standard antibiotics) and demelanizing activity against four micromycetes, showing SS higher activities. As far as we know, this is the first study reporting chemical compounds and bioactivity of morel samples from Portugal and Serbia. Furthermore, a novel method for evaluation of demelanizing activity was presented.The authors are grateful to Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) and COMPETE/QREN/EU (research project PTDC/AGR-ALI/110062/2009; bilateral cooperation action Portugal/Serbia 2011; strategic projects PEst-OE/AGR/UI0690/2011 and PEst-C/QUI/UI0686/2011), and to Serbian Ministry of Education and Science (grant number 173032) for financial support. S.A. Heleno (BD/70304/2010) and L. Barros (BPD/4609/2008) also thank FCT, POPH-QREN and FSE

Bioactive characterization of Persea americana Mill. by-products: A rich source of inherent antioxidants

[EN] Avocado (Persea americana Mill.) is a worldwide consumed fruit, with great interest for cosmetic and pharmaceutical industries; however, 30% of avocado fruits are bio-wastes (peels and kernels), converting them into a potential source of bioactive compounds, such as phenolic compounds. Therefore, the hydroethanolic extracts of peels and kernels of Persea america Mill. var. Hass were analysed regarding their individual phenolic profile by HPLC-DAD/ESI-MS and correlated with their antioxidant, antimicrobial and cytotoxic activities. Avocado by-products presented a very distinct phenolic profile, presenting higher concentration in peels (227.9 mg/g of extract for total phenolic content), mainly in (epi)catechin derivatives (175 mg/g of extract), followed by chlorogenic derivatives (42.9 mg/g of extract). In this study hydrophilic and lipophilic antioxidant assays were performed together for the first time in P. americana by-products, and although kernels showed a great antioxidant potential (EC50 values ranging from 18.1 to 276 mu g/mL), peels presented the highest potential (EC50 ranging from 11.7 to 152 mu g/mL), mainly due to the presence of phenolic compounds, and an overall better performance in the antibacterial assays. Further studies needs to be conducted to better understand the correlation between the presence of phenolic compounds and bioactivities, however, the main objective is to implement these biocompounds in different products and industries, due to results obtained, P. americana peels could be a great alternative in the substitution of synthetic antioxidants.The authors are grateful to the Foundation for Science and Technology(FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. The authors would like to thank the Interreg Espana-Portugal for financial support through the project 0377_Iberphenol_6_E. B. Melgar thanks CONACyT for his grant (No. 329930). The authors are also grateful to the Serbian Ministry of Education, Science and Technological Development, grant number 173032 for financial support.Melgar-Castañeda, B.; Dias, MI.; Ciric, A.; Sokovic, M.; Garcia-Castello, EM.; Rodríguez López, AD.; Barros, L.... (2018). Bioactive characterization of Persea americana Mill. by-products: A rich source of inherent antioxidants. Industrial Crops and Products. 111:212-218. https://doi.org/10.1016/j.indcrop.2017.10.024S21221811