Extraction of phenolics and essential oil from dried sage (Salvia officinalis) using ethanol–water mixtures

Effects of particle size, temperature, contact time, solvent-to-sage ratio and the ethanol–water ratio on the extraction of the active compounds rosmarinic acid, carnosic compounds and essential oil from dried sage (Salvia officinalis) were studied. Optimal extraction conditions giving highest yield of all three active compounds were particle diameter 1 mm, extraction temperature 40 °C, solvent-to-sage ratio of 6:1 and 55–75 wt% ethanol for up to 3 h. This gave an extract equivalent to 14.9% of dry sage, containing 6.9% rosmarinic acid (55% recovery), 10.6% carnosic compounds (75% recovery) and 7.3% essential oil (42% recovery). Scale up of the process by a factor of 100 demonstrated that the optimised laboratory scale process can be carried out without any loss of efficiency at an industrial scale.     

Changes in fatty acid and essential oil composition of sage (Salvia officinalis L.) leaves under NaCl stress

Fatty acids and essential oils from hydroponically cultivated Salvia officinalis leaves were analyzed by GC and GC–MS. Four different levels of NaCl (25, 50, 75 and 100 mM) were applied. The first results showed that salt treatment reduced significantly the plant growth by 61% and the total fatty acids (TFA) content by 32% at 100 mM NaCl. Alpha-linolenic, gadoleic, palmitic and oleic acids were the major fatty acids. Moreover, the polyunsaturated fatty acids decreased, while the monounsaturated ones increased with respect to increasing salinity. Regarding the essential oil composition, the main compounds were α-and β-thujone, 1,8-cineole, camphor, α-humulene, viridiflorol and manool at all salt treatments. The yield had a maximum increase at 75 mM NaCl. Hence, sage can be considered as moderately salt sensitive.     

Antibacterial activity of the essential oils of Salvia officinalis L. and Salvia triloba L. cultivated in South Brazil

The essential oils of Salvia officinalis and Salvia triloba cultivated in South Brazil were analyzed by GC–MS. The major constituents of the oil of S. officinalis were α-thujone, 1,8-cineole, camphor, borneol and β-pinene, whereas those of S. triloba were α-thujone, 1,8-cineole, camphor, and β-caryophyllene. The essential oils of both species exhibited remarkable bacteriostatic and bactericidal activities against Bacillus cereus, Bacillus megatherium, Bacillus subtilis, Aeromonas hydrophila, Aeromonas sobria, and Klebsiella oxytoca. Moreover, the essential oil of S. triloba efficiently inhibited the growth of Staphylococcus aureus. S. aureus and A. hydrophila growth were drastically reduced even in the presence of 0.05 mg/ml of the essential oil of S. triloba.     

Effect of ionising radiation on polyphenolic content and antioxidant potential of parathion-treated sage (Salvia officinalis) leaves

The γ-irradiation effects on polyphenolic content and antioxidant capacity of parathion-pretreated leaves of Salvia officinalis plant were investigated. The analysis of phenolic extracts of sage without parathion showed that irradiation decreased polyphenolic content significantly (p < 0.05) by 30% and 45% at 2 and 4 kGy, respectively, compared to non-irradiated samples. The same trend was observed for the Trolox equivalent antioxidant capacity (TEAC), as assessed by the anionic DPPH and cationic ABTS radical-scavenging assays. The antioxidant potential decreased significantly (p < 0.01) at 2 and 4 kGy, by 11–20% and 40–44%, respectively. The results obtained with a pure chlorogenic acid solution confirmed the degradation of phenols; however, its TEAC was significantly (p < 0.01) increased following irradiation. Degradation products of parathion formed by irradiation seem to protect against a decline of antioxidant capacity and reduce polyphenolic loss. Ionising radiation was found to be useful in breaking down pesticide residues without inducing significant losses in polyphenols.     

Phytochemical profile of Rosmarinus officinalis and Salvia officinalis extracts and correlation to their antioxidant and anti-proliferative activity

The goal of this study was to monitor the anti-proliferative activity of Rosmarinus officinalis and Salvia officinalis extracts against cancer cells and to correlate this activity with their phytochemical profiles using liquid chromatography/diode array detection/electrospray ion trap tandem mass spectrometry (LC/DAD/ESI-MSⁿ). For the quantitative estimation of triterpenic acids in the crude extracts an NMR based methodology was used and compared with the HPLC measurements, both applied for the first time, for the case of betulinic acid. Both extracts exerted cytotoxic activity through dose-dependent impairment of viability and mitochondrial activity of rat insulinoma m5F (RINm5F) cells. Decrease of RINm5F viability was mediated by nitric oxide (NO)-induced apoptosis. Importantly, these extracts potentiated NO and TNF-α release from macrophages therefore enhancing their cytocidal action. The rosemary extract developed more pronounced antioxidant, cytotoxic and immunomodifying activities, probably due to the presence of betulinic acid and a higher concentration of carnosic acid in its phytochemical profile.     

Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells

Salvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4-naphthoquinone-induced DNA damage, and levels of enzymatic and non-enzymatic antioxidants (superoxide dismutase, glutathione peroxidase, glutathione) in human HepG2 cells. To measure antioxidative activity of plant extracts we used three assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The results showed that the oxidant-induced DNA lesions were significantly reduced in cells pre-treated with the plant extracts studied. The observed DNA-protective activity could be explained by both elevation of GPx activity in cells pre-treated with SO and TV and antioxidant activity of SO and TV.     

Antioxidant potentials and rosmarinic acid levels of the methanolic extracts of Salvia verticillata (L.) subsp. verticillata and S. verticillata (L.) subsp. amasiaca (Freyn & Bornm.) Bornm

This study was designed to examine the in vitro antioxidant activities and rosmarinic acid levels of the methanol extracts of Salvia verticillata subsp. verticillata and S. verticillata subsp. amasiaca. The extracts were screened for their possible antioxidant activity by two complementary test systems, namely DPPH free radical-scavenging and β-carotene/linoleic acid systems. In the first case, S. verticillata subsp. verticillata was superior to the subsp. amasiaca with an IC₅₀ value of 14.5 ± 1.21 μg mg⁻¹. In the β-carotene/linoleic acid test system, inhibition capacity of S. verticillata subsp. verticillata was 74.4 ± 1.29%. Antioxidant activities of BHT, ascorbic acid, curcumin and α-tocopherol were determined in parallel experiments. Activity of rosmarinic acid was also screened for better establishing the relationship between rosmarinic acid level and antioxidant activity for the plant extracts. S. verticillata subsp. verticillata had the highest rosmarinic acid level with a value of 28.7 ± 0.89 μg mg⁻¹. There is a strong correlation between the rosmarinic acid level and antioxidant activity potential. Our results showed that rosmarinic acid and its derivatives are more likely to be responsible for most of the observed antioxidant activities of Salvia species.     

Physicochemical properties of a fibrous fraction from chia (Salvia hispanica L.)

An evaluation was done of some physicochemical properties of a fiber-rich fraction (FRF) obtained by dry processing of defatted chia (Salvia hispanica) flour. The fiber-rich fraction (FRF) had 29.56 g/100 g crude fiber content and 56.46 g/100 g total dietary fiber (TDF) content, of which 53.45 g/100 g was insoluble dietary fiber (IDF) and 3.01 g/100 g was soluble dietary fiber (SDF). The FRF water-holding capacity was 15.41 g/g, its water absorption capacity 11.73 g/g, and its organic molecule absorption capacity 1.09 g/g. The FRF also had low oil-holding (2.02 g/g) and water adsorption (0.3 g/g) capacities. Emulsifying activity in this fraction was 53.26% and emulsion stability was 94.84%. Its evaluated antioxidant activity was 488.8 μmol/L Trolox equivalents/g FRF, which is higher than for many cereals and similar to drinks such as wine, tea, coffee and orange juice. The chia FRF values for the evaluated properties, particularly for water-holding, oil-holding and organic molecule absorption capacity, suggest it could be a useful ingredient in dietetic products such as baked and fried foods, among others.     

Phenolic profiles of cultivated, in vitro cultured and commercial samples of Melissa officinalis L. infusions

Melissa officinalis L. (lemon balm) is normally consumed as an infusion and presents therapeutic properties, such as sedative, carminative and antispasmodic, also being included in some pharmaceutical preparations. The phenolic profiles of different samples of lemon balm, prepared as infusions, were evaluated by HPLC-DAD-ESI/MS. The profiles were compared in order to understand the differences between cultivated, in vitro cultured and commercial (bags and granulated) samples. All the samples showed a similar phenolic profile, presenting differences only in the quantities found of each compound. Rosmarinic acid was the most abundant compound, being higher in commercial samples, especially in tea bag sample (55.68 mg/g of infusion) and lower in in vitro cultured sample (15.46 mg/g). Moreover, dimers, trimers and tetramers of caffeic acid were identified and quantified for the first time in lemon balm. Only one flavonoid, luteolin-3′-O-glucuronide was found in all the samples, ranging from 8.43 mg/g in commercial granulate sample to 1.22 mg/g in in vitro cultured sample. Overall, cultivated and in vitro cultured samples presented the lowest amounts of phenolic compounds (59.59 and 30.21 mg/g, respectively); otherwise, commercial samples showed the highest contents (109.24 mg/g for tea bag and 101.03 mg/g for granulate sample). The present study shows that infusion of lemon balm can be a source of phenolic compounds, known for their bioactive effects.     

Chemical composition and in vitro antioxidative activity of a lemon balm (Melissa officinalis L.) extract

The leaf material of lemon balm (Melissa officinalis L.) was extracted with 450 ml/l aqueous ethanol by medium pressure liquid-solid extraction. The total phenolic content of the extract was estimated as gallic acid equivalents by Folin-Ciocalteu reagent method and a qualitative-quantitative compositional analysis was carried out using high performance liquid chromatography coupled with photodiode array detection. The lemon balm extract contained hydroxycinnamic acid derivatives and flavonoids with caffeic acid, m-coumaric acid, eriodictyol-7-O-glucoside, naringin, hesperidin, rosmarinic acid, naringenin, hesperetin being identified based on their chromatographic behaviour and spectral characteristics. The extract was also investigated for potential in vitro antioxidant properties in iron(III) reduction, iron(II) chelation, 1,1-diphenyl-2-picrylhydrazyl, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonate), superoxide anion and nitric oxide free-radical scavenging, and inhibition of β-carotene-linoleic acid bleaching assays. The extract demonstrated antioxidant activity in all the assays. However, it was not as potent as the positive controls except in the β-carotene-linoleic acid bleaching assay, where its activity was superior to that of gallic and caffeic acids and statistically indistinguishable from quercetin and BHA. The exceptionally high antioxidant activity and the fact that this assay is of biological relevance warrants further investigation of lemon balm extract in ex vivo and in vivo models of oxidative stress.     

Influence of the phenophase on the phenolic profile and antioxidant properties of Dalmatian sage

This study aimed to research the influence of phenophase on the phenolic profile (phenolic acids, flavonoids and stilbenes) and related antioxidant properties of sage, one of the most characteristic plants of Dalmatian karst. The total phenol and flavonoid contents in sage leaves were determined spectrophotometrically, while the principal phenolics were determined using HPLC-RP-DAD. Antioxidant properties of this well known medicinal plant were determined as free radical scavenging activity (DPPH), ferric reducing/antioxidant power (FRAP) and by Briggs-Rauscher oscillating reaction (BR). The results strongly indicate that Dalmatian sage leaves are rich source of valuable phenolics, mainly phenolic acids, with extremely good antioxidant properties. The presence of resveratrol or its derivatives was confirmed in all extracts. The best results for total phenols and flavonoids, as well as the best antioxidant properties were obtained for May sage, while the highest amounts of catechin monomers and compounds from group of stilbenes were found in February extract.     

Antifungal activity of the honey flavonoid extract against Candida albicans

Candida albicans is the most prevalent dimorphic pathogen in humans. We investigated the potential protective effect of honey flavonoid extract (HFE) on Candida dimorphism induced by RPMI 1640 medium. Yeast to hyphal transition was dose dependently prevented when Candida cultures were treated with HFE for 6 h (germ-tube formation) and 18 h (hypha elongation). Since during hyphal growth remarkable amounts of reactive oxygen species (ROS) are generated, we investigated whether HFE affects the generation of ROS, the glutathione level and the activity of glutathione-dependent enzymes. Treatment of Candida cells with 48 μg/ml (MIC₅₀) of HFE for 6 or 18 h inhibited the dimorphic conversion by supporting of the intracellular glutathione level. HFE exerts a dual protective effect inhibiting both ROS generation during germ-tube formation and γ-glutamyltranspeptidase activity, responsible for GSH degradation, during hypha elongation. These results show that HFE confers a significant protection against yeast to hyphal transition of C. albicans.     

Effect of sage (Salvia officinalis) on the oxidative stability of Chinese-style sausage during refrigerated storage

The objective of this study was to assess the effect of sage, at levels of 0.05%, 0.1% and 0.15% (w/w), on the oxidative stability of Chinese-style sausage stored at 4 °C for 21 days. The results showed that inclusion of sage in sausages resulted in lower L* values (P < 0.05) and higher a* values (P < 0.05) compared to the control. During refrigerated storage, sausages containing sage showed significantly retarded increases in TBARS values, and in the formation of protein carbonyls (P < 0.05), but showed accelerated losses of thiol groups (P < 0.05). Addition of sage to the sausages at levels of 0.1% and 0.15% reduced textural deterioration during refrigerated storage (P < 0.05). Sage used in this study had no negative effects on the sensory properties of sausages.     

Changes in valerenic acids content of valerian root (Valeriana officinalis L. s.l.) during long-term storage

Dried valerian (Valeriana officinalis) root powder was stored at 5, 14 and 30 °C under low, moderate and high humidity conditions for 6 months, and the level of the valerenic acids monitored on a monthly basis. From an initial moisture content of 5 g/kg, the moisture level during storage decreased in root powder stored at low humidity and increased during storage at high humidity, with the effect greatest at 30 °C.     

Determination of carnosic acid and rosmarinic acid in sage by capillary electrophoresis

A simple and rapid capillary electrophoresis method was developed for the identification and quantitative determination of two antioxidative compounds – carnosic acid and rosmarinic acid – in the extracts of commercial Sage (Salvia officinalis) tea-bags. Capillary zone electrophoretic separation of carnosic and rosmarinic acids was performed using 40 mmol/l borate, at pH 9.6 as the running buffer. Weighed sage samples were extracted from tea-bags by sonification and the extracts were directly injected without any purification and pre-separation process. Coumarin was used as internal standard for quantitation and the limits of detection for carnosic acid and rosmarinic acid were obtained as 2.79 and 3.18 μg/ml, respectively using UV detection at 210 nm.     

Phenolic composition and biological activities of Salvia halophila and Salvia virgata from Turkey

The aerial parts of Salvia halophila and Salvia virgata were subjected to Soxhlet extraction with different solvents such as n-hexane, ethyl acetate, methanol, and aqueous methanol (50%). Plants were also extracted with water under reflux. The effects of the extracts were studied in p-benzoquinone-induced abdominal constriction test for the assessment of antinociceptive activity and carrageenan-induced hind paw edema and 12-O-tetradecanoyl-13-acetate (TPA)-induced ear edema models in mice for the anti-inflammatory activity. The extracts were analysed using a HPLC–PDA method. Results showed that methanol extract of S. virgata significantly inhibited carrageenan-induced paw edema and p-benzoquinone-induced abdominal constriction at 100 mg/kg dose, while it showed no effect in the TPA-induced ear edema. On the other hand, the other extracts did not show any inhibitory antinociceptive and anti-inflammatory activities in these in vivo models. Rosmarinic acid was found as main constituent in the extracts, while caffeic acid and luteolin derivatives were also detected.     

Inhibitory effects of Lemon balm (Melissa officinalis, L.) extract on the formation of advanced glycation end products

Lemon balm (Melissa officinalis) is a medicinal herb possessing functional compounds with unexplored anti-glycative action. The anti-glycative activity of Lemon balm extract was evaluated in the bovine serum albumin (BSA)/glucose system. The level of glycation, conformational alterations and protein binding to RAGE receptors were assessed by specific fluorescence, Congo red binding assay, circular dichroism, ligand and Western blotting. Ethanol fractions of Melissa leaf exhibited the highest inhibitory effects on the formation of advanced glycation end products (AGEs) and the late stage of glycation process. Significant alteration in the secondary structure of albumin was observed upon glycation, which was mitigated by applying the herb extract. Moreover, upon treatment with balm extract, glycated albumin adopts a secondary structure impeding its detection by RAGE receptors of microglial cells. Our results represent the anti-glycative properties of Melissa extract and its application for possible treatment of AGE-associated diseases.     

Steady shear flow properties of wild sage (Salvia macrosiphon) seed gum as a function of concentration and temperature

The steady shear flow properties of dispersions of a new potential hydrocolloid, sage seed gum (SSG), were determined as a function of concentration (0.5–2% w/w), and temperature (20–50 °C). SSG dispersions exhibited strong shear-thinning behavior at all conditions tested, which was even more pronounced than commercial hydrocolloids like xanthan, guar gum and locust bean gum. Different time-independent rheological models were used to fit the experimental data, although the Herschel–Bulkley model (H–B) was found the best model to describe steady shear flow behavior of SSG. An increase in gum concentration led to a large increase in yield stress and consistency coefficient values, whereas there was no definite trend with an increase in temperature. On the other hand, the above-mentioned increases in concentration and temperature did not yield a clear evolution of the shear-thinning characteristics of SSG dispersions. An Arrhenius-type model was also used to describe the effect of temperature. The activation energy (E_a) appeared in the range of 3949–16384 J/mol, as concentration increased from 0.5 to 2%, at a shear rate of 100 s⁻¹. The yield stress values estimated by viscoplastic rheological models were much higher than the data determined by stress ramp method. Apparent viscosity of SSG surpassed many commercial hydrocolloids such as guar gum, locust bean gum, Tara gum, fenugreek gum and konjac gum at the same conditions, which suggest it as a very good stabilizer in food formulations.     

The importance of almond (Prunus amygdalus L.) and its by-products

Almond fruit consists of three or correctly four portions: kernel or meat, middle shell, outer green shell cover or almond hull and a thin leathery layer known as brown skin of meat or seedcoat. The nutritional importance of almond fruit is related to its kernel. Other parts of fruit such as shells and hulls were used as livestock feed and burned as fuel. In the past decades, different phenolic compounds were characterised and identified in almond seed extract and its skin, shell and hull as almond by-products. In addition, polyphenols are abundant micronutrients in the human diet, and evidence for their role in the prevention of degenerative diseases such as cancer and cardiovascular diseases is emerging. The health effects of polyphenols depend on the amount consumed and on their bioavailability. In this contribution, various phenolic compounds present in almond and its by-products, their antioxidant properties and potential use as natural dietary antioxidant, as well as their other beneficial compounds and applications are reviewed.