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Julbernardia paniculata and Pterocarpus angolensis are two plant species with important application in African traditional medicine, particularly in Angola, in the treatment of several diseases. However, scientific studies concerning these species are scarce. The goal of this work was to know better which medicinal approaches are used by the Huíla population in Angola by means of ethnobotanical surveys. Furthermore, extracts of both plants were phytochemically characterized. Antioxidant, anti-inflammatory, wound-healing activities, and potential cytotoxicity were also studied. With this study it was possible to verify that 67% of the individuals that use medicinal plants are women, and their main therapeutic uses are the treatment of problems of the digestive system and skin disorders. Barks of J. paniculata and leaves of P. angolensis are the most often used plant parts. Through high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD) and GC-MS it was possible to characterize the chemical composition of the two species, which are rich in phenolic compounds, terpenes, terpenoids, sesquiterpenoids and fatty acids. Both plants showed to possess antioxidant, anti-inflammatory proprieties, and wound-healing activity. To the best of our knowledge, this is the most comprehensive study of these two species and the first ethnobotanical and ethnopharmacological study of medicinal plants from this region of Angola.

Alkylresorcinols are compounds which belong to the family of phenolic lipids, and are usually found in numerous biological species. In the particular case of higher plants, alkylresorcinols have been found in various counterparts with chains of thirteen to twenty-seven carbon atoms containing several saturations. Due to the demonstrated antimicrobial properties of many naturally occurring members of the alkylresorcinols family, it is possible to conclude that these compounds act as defensive agents in plants. Previous studies led to the isolation and identification of 5-alkylresorcinols that cleave DNA. Additionally, in the literature, there are several other biological effects attributed to some resorcinol derivatives, namely, cytotoxic, anticarcinogenic, antiproliferative, antileishmanial and antioxidant properties. This mini-review intends to outline the biological activities of the most relevant alkylresorcinols isolated from plants and to propose future directions for subsequent studies regarding the effective biological effects of this class of compounds.

These past years have seen an enormous development of the area of natural antioxidants and antimicrobials. Eucalyptus globulus is widely cultivated in subtropical and Mediterranean regions in intensive short rotation coppice plantations. In the Portuguese context, E. globulus is the third species in terms of forest area. The stump is the basal part of the tree, including the near-the-ground stem portion and the woody roots that remain after stem felling. The purpose of this work was to study the phytochemical profile and to evaluate the antioxidant and antimicrobial properties of several crude stump wood and stump bark extracts of E. globulus, comparing it with similar extracts of E. globulus wood (industrial chips). The results showed the presence of high concentrations of total phenolic compounds (>200 mg GAE/g extract) and flavonoids (>10 mg QE/g extract) in E. globulus stump extracts. Generally the stump wood extracts stands out from the other ones, presenting the highest percentages of inhibition of linoleic acid oxidation. It was also possible to conclude that the extracts were more active against Gram-positive bacteria, presenting low MIC values. This study thus provides information supporting the economic valorization of E. globulus stump wood.

In the ecosystem of Serra Da Estrela, some plant species have the potential to be used as raw material for extraction of bioactive products. The goal of this work was to determine the phenolic, flavonoid, tannin and alkaloid contents of the methanolic extracts of some shrubs (Echinospartum ibericum, Pterospartum tridentatum, Juniperus communis, Ruscus aculeatus, Rubus ulmifolius, Hakea sericea, Cytisus multiflorus, Crataegus monogyna, Erica arborea and Ipomoea acuminata), and then to correlate the phenolic compounds and flavonoids with the antioxidant activity of each extract. The Folin-Ciocalteu's method was used for the determination of total phenols, and tannins were then precipitated with polyvinylpolypyrrolidone (PVPP); a colorimetric method with aluminum chloride was used for the determination of flavonoids, and a Dragendorff's reagent method was used for total alkaloid estimation. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and beta-carotene bleaching tests were used to assess the antioxidant activity of extracts. The identification of phenolic compounds present in extracts was performed using RP-HPLC. A positive linear correlation between antioxidant activity index and total phenolic content of methanolic extracts was observed. The RP-HPLC procedure showed that the most common compounds were ferulic and ellagic acids and quercetin. Most of the studied shrubs have significant antioxidant properties that are probably due to the existence of phenolic compounds in the extracts. It is noteworthy to emphasize that for Echinospartum ibericum, Hakea sericea and Ipomoea acuminata, to the best of our knowledge, no phytochemical studies have been undertaken nor their use in traditional medicine been described.

The antioxidant activity of the phenolic compounds present in industrial black liquors obtained from the two cooking processes (kraft and sulphite) used in Portugal to produce Eucalyptus globulus pulp was evaluated. The black liquors treated at several pH values were extracted with ethyl acetate. Phenolic fractions were further separated by liquid chromatography of the crude extracts of kraft liquor at pH = 6 and sulphite liquor at the original pH. Total phenolic content was determined in terms of gallic acid equivalents (Folin-Ciocalteu colorimetric method), and the antioxidant activity in the crude extracts at several pH values and in the separated fractions was measured using the DPPH test for radical scavenging capacity. The total phenolic content of crude extracts and separated fractions ranged from 92.7 to 181.6 and from 91.6 to 1,099.6 mg GAE/g, respectively, while the antioxidant activity index (AAI) ranged from 2.20 to 3.41 and from 2.21 to 11.47 respectively, showing very strong antioxidant activity in all studied cases. The fractions separated by column chromatography were submitted to mass spectrometry analysis and the results were compared to others in the literature of natural products, mainly from Eucalyptus, and the characteristic bands of functional groups were identified by ¹H-NMR and FTIR. These methods allowed the identification of 17 phenolic compounds.

Essential oils (EOs) and their components extracted from medicinal and aromatic plants are used in several areas, such as perfumery and chemical, cosmetic, food, and pharmaceutical industries. Considering the different applications of EOs, this work aimed to screen the composition and the bioactivities properties of the EOs of Foeniculum vulgare, Helichrysum stoechas, Mentha pulegium, Pinus pinaster, Ruta graveolens , and Thymus mastichina. Gas chromatography–mass spectrometry revealed the presence of different compounds in EOs F. vulgare (12), H. stoechas (27), M. pulegium (8), P. pinaster (24), R. graveolens (8), and T. mastichina (16). All the EOs showed antioxidant activity acting through inhibition of lipid peroxidation, while only two EOs (H. stoechas and M. pulegium) scavenged the free radicals of DPPH. Mentha pulegium and T. mastichina EOs showed the strongest antimicrobial activity. Also, the effect on the fibroblast's viability was directly proportional to the EOs concentration, and the highest cytotoxic effect was registered with R. graveolens EO. The present study revealed significant bioactive properties of different EOs, highlighting M. pulegium and T. mastichina EOs to be considered in further studies for potential use in the food and pharmaceutical industries, due to their antioxidant and antimicrobial properties. [ABSTRACT FROM AUTHOR]

Berries possess structurally diverse polyphenols that may have different effects on their antioxidant properties; a combination of various berries may exhibit additive, synergistic, or antagonistic interactions between their different bioactive compounds. Even if this kind of interactions between the antioxidant properties of green tea polyphenols and other plant-derived foods has already been studied, in what concerns berries and their major polyphenols, such study has not yet been undertaken. Therefore, the goal of this work was to study the individual antioxidant activity of 19 selected major polyphenols from the most consumed berries as well as the activity of the mixtures resulting from the 171 possible combinations between them using 2 in vitro model systems. It was observed that 2.92% of the mixtures presenting synergistic effects in scavenging DPPH free radicals were composed by cyanidin, and 2.34% composed by cyanidin-3- O-glucoside. These results indicate that cyanidin, a common anthocyanin present in berries, is responsible for the enhancement of the radical scavenging properties of other berries' polyphenols. [ABSTRACT FROM AUTHOR]

The consumption of berries and their contribution to improving the human health is a subject of considerable interest, have already resulted in several research projects and numerous clinical trials in humans. The main goal of this study was to evaluate the phytochemical composition (total reducing sugars, total phenolics, flavonoids, and anthocyanins) of some commercially-available juices of berries and associating it to their physicochemical (pH, density, and total solids), rheological and antioxidant properties. It was observed that in general, the juices analysed presented great concentrations of polyphenols and anthocyanins; and, in what concerns to their rheological properties, non-Newtonian pseudoplastic fluid characteristics (n < 1) were observed. The antioxidant properties of the juices were evaluated using both the DPPH free radical scavenging assay and the β-carotene bleaching test. Overall, the results of the % Inhibition of DPPH free radical by the tested juices indicate that they possess considerable capacity to scavenge free radicals, resulting in good antioxidant properties. This study demonstrated that the physicochemical properties of the juices influence their rheological behavior; and the phytochemical composition impacts their antioxidant properties. Due to their antioxidant capacities, juices of berries could be considered functional foods. [ABSTRACT FROM AUTHOR]

Artemisia jordanica (AJ) is one of the folkloric medicinal plants and grows in the arid condition used by Palestinian Bedouins in the Al-Naqab desert for the treatment of diabetes and gastrointestinal infections. The current investigation aimed, for the first time, to characterize the (AJ) essential oil (EO) components and evaluate EO's antioxidant, anti-obesity, antidiabetic, antimicrobial, anti-inflammatory, and cytotoxic activities. The gas chromatography-mass spectrometer (GC-MS) technique was utilized to characterize the chemical ingredients of (AJ) EO, while validated biochemical approaches were utilized to evaluate the antioxidant, anti-obesity and antidiabetic. The microbicidal efficacy of (AJ) EO was measured utilizing the broth microdilution assay. Besides, the cytotoxic activity was estimated utilizing the (MTS) procedure. Finally, the anti-inflammatory activity was measured utilizing a COX inhibitory screening test kit. The analytical investigation revealed the presence of 19 molecules in the (AJ) EO. Oxygenated terpenoids, including bornyl acetate (63.40%) and endo-borneol (17.75%) presented as major components of the (AJ) EO. The EO exhibited potent antioxidant activity compared with Trolox, while it showed a weak anti-lipase effect compared with orlistat. In addition, the tested EO displayed a potent α-amylase suppressing effect compared with the positive control acarbose. Notably, the (AJ) EO exhibited strong α-glucosidase inhibitory potential compared with the positive control acarbose. The EO had has a cytotoxic effect against all the screened tumor cells. In fact, (AJ) EO showed potent antimicrobial properties. Besides, the EO inhibited the enzymes COX-1 and COX-2, compared with the anti-inflammatory drug ketoprofen. The (AJ) EO has strong antioxidant, antibacterial, antifungal, anti-α-amylase, anti-α-glucosidase, and COX inhibitory effects which could be a favorite candidate for the treatment of various neurodegenerative diseases caused by harmful free radicals, microbial resistance, diabetes, and inflammations. Further in-depth investigations are urgently crucial to explore the importance of such medicinal plants in pharmaceutical production. [ABSTRACT FROM AUTHOR]

Blood pressure control in hypertensive subjects calls for changes in lifestyle, especially diet. Tomato is widely consumed and rich in healthy components (i.e., carotenoids, vitamins and polyphenols). The aim of this study was to evaluate the chemical composition and antihypertensive effects of locular gel reconstituted in serum of green tomatoes of "Camone" variety. Tomato serum and locular gel were chemically characterised. The antihypertensive effects of the locular gel in serum, pure tomatine, and captopril, administered by oral gavage, were investigated for 4 weeks in male spontaneously hypertensive and normotensive rats. Systolic blood pressure and heart rate were monitored using the tail cuff method. Body and heart weight, serum glucose, triglycerides and inflammatory cytokines, aorta thickness and liver metabolising activity were also assessed. Locular gel and serum showed good tomatine and polyphenols content. Significant reductions in blood pressure and heart rate, as well as in inflammatory blood cytokines and aorta thickness, were observed in spontaneously hypertensive rats treated both with locular gel in serum and captopril. No significant effects were observed in normotensive rats. Green tomatoes locular gel and serum, usually discarded during tomato industrial processing, are rich in bioactive compounds (i.e., chlorogenic acid, caffeic acid and rutin, as well as the glycoalkaloids, α-tomatine and dehydrotomatine) that can lower in vivo blood pressure towards healthier values, as observed in spontaneously hypertensive rats. [ABSTRACT FROM AUTHOR]

The interest in plant polyphenol antioxidants has increased remarkably over the last decade mostly because of their protective effects against different diseases, including cardiovascular, inflammatory and neurological diseases, cancer as well as for retarding aging. Many naturally occurring polyphenols found in plants and spices have also been shown to possess antimicrobial properties and could serve as a source of antimicrobial agents. Eucalyptus globulus and Eucalyptus radiata are well known species that provide essential oils. These oils are in great demand in the market, since they find a vast array of applications. The present study was performed to evaluate some bioactivities of the essential oils from E. globulus and E. radiata , namely their antioxidant, antibacterial and anti-quorum sensing properties. Moreover, its chemical composition was assessed and the potential synergistic activity with conventional antibiotics against Acinetobacter baumannii strains was also evaluated. The major component of the E. globulus oil was 1,8-cineole, also known as eucalyptol (63.81%), and in the E. radiata oil, the principal component was limonene (68.51%). It was possible to conclude that both eucalypt essential oils presented relevant radical scavenging properties and also had the capacity to inhibit the lipid peroxidation. The E. globulus oil antioxidant properties stand out when compared to the E. radiata oil. The E. radiata oil had a more pronounced antibacterial activity than E. globulus oil. The studied eucalypt essential oils can act as potential improving agents of antibiotics against A. baumannii , considering the synergic effect obtained between these oils and conventional antibiotics. Both eucalypt essential oils now studied can inhibit the quorum sensing phenomena, inhibiting quorum sensing-regulated violacein pigment production in bacteria without interfering with their growth. [ABSTRACT FROM AUTHOR]