Composition and Antioxidant Properties of Pigments of Mediterranean Herbs and Spices as Affected by Different Extraction Methods

Naturally-derived phenethyl isothiocyanate modulates apoptotic induction through regulation of the intrinsic cascade and resulting apoptosome formation in human malignant melanoma cells

Malignant melanoma is the most aggressive type of skin cancer with increasing incidence rates worldwide. On the other hand, watercress is a rich source of phenethyl isothiocyanate (PEITC), among others, which has been widely investigated for its anticancer properties against various cancers. In the present study, we evaluated the role of a watercress extract in modulating apoptotic induction in an in vitro model of human malignant melanoma consisting of melanoma (A375, COLO-679, COLO-800), non-melanoma epidermoid carcinoma (A431) and immortalized, non-tumorigenic keratinocyte (HaCaT) cells. Moreover, the chemical composition of the watercress extract was characterized through UPLC MS/MS and other analytical methodologies. In addition, cytotoxicity was assessed by the alamar blue assay whereas apoptosis was determined, initially, by a multiplex activity assay kit (measuring levels of activated caspases -3, -8 and -9) as well as by qRT-PCR for the identification of major genes regulating apoptosis. In addition, protein expression levels were evaluated by western immunoblotting. Our data indicate that the extract contains various phytochemicals (e.g. phenolics, flavonoids, pigments, etc.) while isothiocyanates (ITCs; especially PEITC) were the most abundant. In addition, the extract was shown to exert a significant time- and dose-dependent cytotoxicity against all malignant melanoma cell lines while non-melanoma and non-tumorigenic cells exhibited significant resistance. Finally, expression profiling revealed a number of genes (and corresponding proteins) being implicated in regulating apoptotic induction through activation of the intrinsic apoptotic cascade. Overall, our data indicate the potential of PEITC as a promising anti-cancer agent in the clinical management of human malignant melanoma.

Investigating the Mechanism of Cadmium-Tolerant Bacterium Cellulosimicrobium and Ryegrass Combined Remediation of Cadmium-Contaminated Soil

Cadmium (Cd) pollution has been rapidly increasing due to the global rise in industries. Cd not only harms the ecological environment but also endangers human health through the food chain and drinking water. Therefore, the remediation of Cd-polluted soil is an imminent issue. In this work, ryegrass and a strain of Cd-tolerant bacterium were used to investigate the impact of inoculated bacteria on the physiology and biochemistry of ryegrass and the Cd enrichment of ryegrass in soil contaminated with different concentrations of Cd (4 and 20 mg/kg). The results showed that chlorophyll content increased by 24.7% and 41.0%, while peroxidase activity decreased by 56.7% and 3.9%. In addition, ascorbic acid content increased by 16.7% and 6.3%, whereas glutathione content decreased by 54.2% and 6.9%. The total Cd concentration in ryegrass increased by 21.5% and 10.3%, and the soil's residual Cd decreased by 86.0% and 44.1%. Thus, the inoculation of Cd-tolerant bacteria can improve the antioxidant stress ability of ryegrass in Cd-contaminated soil and change the soil's Cd form. As a result, the Cd enrichment in under-ground and above-ground parts of ryegrass, as well as the biomass of ryegrass, is increased, and the ability of ryegrass to remediate Cd-contaminated soil is significantly improved.

An Update on Recent Studies Focusing on the Antioxidant Properties of Salvia Species

Nutrition has crucial effects and a significant role in disease prevention. Recently, nutraceuticals have attracted much attention in scientific research due to their pleiotropic effects and relatively non-toxic behavior. Among the biological effects displayed by plants belonging to the Lamiaceae family, such as antibacterial, anticancer, anti-inflammatory, and anticholinesterase, sage is well known for its antioxidant properties and is a rich source of numerous compounds that are biologically active, amongst them polyphenols, with more than 160 types identified. In this review we summarized some of the significant studies published in the last decade reporting the most employed extraction methods and the different assays that are useful for establishing the antioxidant properties of some sage species. Even though the scientific literature contains plenty of data regarding the antioxidant properties of many sage species, further studies are needed in order to gain a deeper understanding of the mechanism of action and the compounds responsible for their antioxidant activity. Finally, it should be taken into account that the data on the antioxidant properties of sage extracts are often difficult to compare with each other, since a series of variables in the extraction procedures, the type of assay used, and standardization may affect the final result.

Optimisation of Almond-Based Dairy-Free Milk Alternative Formulation Fortified with Myrtle, Bay Leaf and Fennel Extracts§

Research background

Herbs and spices used in traditional medicine are nowadays increasingly used in combinations to create functional food formulations aimed at treating specific symptoms and disorders. Among herbs originating from the Mediterranean region, extracts of myrtle (Myrtus communis L.), bay leaf (Laurel nobilis L.) and fennel (Foeniculum vulgare Mill.) are traditionally used for gastrointestinal disorders. When considering how to incorporate these extracts into products, dairy-free milk alternatives provide an excellent base with almond-based drinks being among the most popular within this group.

Experimental approach

The aim of this study is therefore to optimise the formulation of an almond drink fortified with a 25 % (on dry mass basis) aqueous herbal extract containing myrtle, bay leaf (25 % each) and fennel seed (50 %) extracts. A central composite design with 20 formulations varied the content of φ(aqueous herbal extract)=2-6 %, lecithin as emulsifier 0.15-0.45 and xylitol as sweetener 2-5 % (m/V), while antioxidant activity, total phenolic content and sensory properties were determined as dependent variables.

Results and conclusions

The antioxidant activity and total phenolic content of the prepared almond drink formulations increased with the amount of added concentrated aqueous herbal extracts, as did the colour, herbal odour and flavour, bitterness and aftertaste. The addition of lecithin resulted in a darker colour and the sweetness was increased by the xylitol content. All formulations had good overall attractiveness, which increased with higher xylitol content.

Novelty and scientific contribution

The current work offers new insights into the optimisation of fortified dairy-free alternatives. The addition of myrtle, bay leaf and fennel seed extracts to almond drink-based formulations resulted in a 12-fold increase in antioxidant activity. Xylitol masks the potential bitterness of the phenolic compounds so that higher amounts of extracts can be added.

Effects of biochar on the physiology and heavy metal enrichment of Vetiveria zizanioides in contaminated soil in mining areas

The effects of biochar addition on the physiological and biochemical characteristics of Vetiveria zizanioides, and the enrichment of heavy metals, were studied herein. The aim was to provide a theoretical reference for biochar to regulate the growth of V. zizanioides in the heavy metal-contaminated soil of mining areas and the enrichment capacity of Cu, Cd, and Pb. The results showed that the addition of biochar significantly increased the contents of various pigments in the middle and late growth stages of V. zizanioides, reduced the contents of malondialdehyde (MDA) and proline (Pro) in each growth period, weakened the peroxidase (POD) activity during the entire growth period; superoxide dismutase (SOD) activity decreased in the initial stages and substantially increased in the middle and late stages. The addition of biochar reduced the enrichment of Cu in the roots and leaves of V. zizanioides, while the enrichment of Cd and Pb increased. In conclusion, it was found that biochar could reduce the toxicity of heavy metals in contaminated soil in the mining area, affect the growth of V. zizanioides and its accumulation of Cd and Pb, and is, therefore, beneficial to the restoration of contaminated soil and the overall ecological restoration of the mining area.

Herbal Leaves Can Suppress Oxidation of Perilla Oil

Perilla oil is a valuable food source of α-linolenic acids. However, its high reactivity with oxygen shortens its shelf-life after opening. This study investigated the antioxidative profiles of 15 plant materials, including herbs, and examined methods to suppress the oxidation of perilla oil using these plant materials. These plant materials had wide ranges of phenolic, carotenoid, and chlorophyll contents. They exhibit radical scavenging activities and suppress lipid peroxidation, which show highly positive correlations with the phenolic contents. Dipping most of the plant materials examined in perilla oil suppressed its oxidation, and the peroxide values of the oil mixtures indicated a negative correlation with the carotenoid and chlorophyll contents of the plant materials. The leaves of Angelica, Astragalus, and Thyme herbs exhibited the same effect as that of ascorbyl palmitate, which was used as a positive control after 8 wk of incubation in the dark. The suppression of lipid peroxidation was found to be related to the herbal contents of carotenoids and chlorophylls, rather than phenols. Hence, herbal leaves can suppress the oxidation of perilla oil in the dark. The oxidation of n-3 polyunsaturated fatty acids could be suppressed effectively by utilizing plant materials with abundant carotenoids and chlorophylls.

The Influence of Cryogrinding on Essential Oil, Phenolic Compounds and Pigments Extraction from Myrtle (Myrtus communis L.) Leaves

The aim of this study was to investigate the influence of cryogrinding pretreatment on the recovery of essential oil, phenolics and pigments from myrtle leaves. The duration of cryogrinding (3, 6 and 9 min) in combination with the duration of hydrodistillation (30, 60 and 90 min) for the isolation of essential oils and the duration of hydroethanolic extraction (5, 10 and 15 min) for the isolation of phenols and pigments were studied as independent factors in a full factorial design. The major volatile components detected in myrtle leaf essential oil were myrtenyl acetate, 1,8-cineole, α-pinene and linalool. The most abundant phenols detected were myricetin derivatives (myricetin 3-O-galactoside and myricetin 3-O-rhamnoside), galloylquinic acid, myricetin and digalloylquinic acid, while the major pigments were chlorophyll b, pheophytin a and lutein. A 3 min cryogrinding pretreatment significantly increased the yield and concentrations of essential oil volatile compounds and reduced the distillation time to 30 min. A 9 min cryogrinding pretreatment and 15 min extraction resulted in at least 40% higher concentrations of phenolic compounds and pigments in the extracts when compared to the untreated control. According to the results obtained, cryogrinding can significantly increase the yield of myrtle EO and extracts and also modulate their composition.

The Changes in Bioactive Compounds and Antioxidant Activity of Chia (Salvia hispanica L.) Herb under Storage and Different Drying Conditions: A Comparison with Other Species of Sage

Studies on herb chia (Salvia hispanica L.) are very limited. Therefore, the aim of this study was to assess how different drying methods and periods of storage affect the bioactive properties of the herb Salvia hispanica and to compare it with other species of sage (Salvia officinalis L. and Salvia sclarea L.). In fresh herbs, directly after drying (freeze-drying, natural drying, and drying at 30, 40, and 50 °C), and after storage (3, 6, and 12 months), the following analyses were performed: content of total carotenoids and total polyphenols, polyphenol profile (including 25 compounds), and antioxidant activity. Additionally, the basic chemical compositions of the herbs were analyzed. To the best of our knowledge, the content of total carotenoids and the quantitative polyphenol profile in Salvia hispanica and Salvia sclarea were evaluated for the first time. The obtained results showed that the barely investigated herb Salvia hispanica is rich in polyphenolic compounds and shows high antioxidant activity. In all the tested species, rosmarinic acid was the most abundant polyphenolic compound. The use of different drying methods allowed us to determine that freeze-drying was the most effective for preserving polyphenols and carotenoids. Long-term storage up to 12 months resulted in a gradual reduction in antioxidant activity and in the content of polyphenols and carotenoids.