Antimutagenic and Antioxidant Potentials of Teucrium ramosissimum Essential Oil

A Review of the Phytochemistry, Traditional Uses and Biological Activities of the Essential Oils of Genus Teucrium

The genus Teucrium is a large and polymorphic genus of the Lamiaceae family distributed in mild climate zones, particularly in the Mediterranean basin and Central Asia. Studies of nonvolatile constituents of Teucrium species showed that they are a rich source of neo-clerodane diterpenoids, considered as chemotaxonomic markers of the genus. In addition to the nonvolatile metabolites, there has been a large interest in the essential oils of this genus. In this review, a complete survey of the chemical composition and biological properties of the essential oils isolated from Teucrium taxa is provided. In traditional medicine, since ancient times, species of this genus have been widely implemented for their biological properties, including antimicrobial, anti-inflammatory, antispasmodic, insecticidal, anti-malaria, etc. Therefore, a complete review of all of the traditional uses of Teucrium taxa are also reported.

In vitro toxicological evaluation of essential oils and their main compounds used in active food packaging: A review

Essential oils (EOs) and their main constituent compounds have been extensively investigated due to their application in the food industry for improving the shelf life of perishable products. Although they are still not available for use in food packaging in the market in Europe, considerable research in this field has been carried out recently. The safety of these EOs should be guaranteed before being commercialized. The aim of this work was to review the scientific publications, with a primary focus on the last 10 years, with respect to different in vitro toxicological aspects, mainly focussed on mutagenicity/genotoxicity. In general, fewer genotoxic studies have been reported on EOs in comparison to their main components, and most of them did not show mutagenic activity. However, more studies are needed in this field since the guidelines of the European Food Safety Authority have not always been followed accurately. The mutagenic/genotoxic activities of these substances have been related to metabolic activation. Therefore, in vivo tests are required to confirm the absence of genotoxic effects. Considering the great variability of the EOs and their main compounds, a case-by-case evaluation is needed to assure their safe use in food packaging.

Cytogenetic, cytotoxic and GC-MS studies on concrete and absolute oils from Taif rose, Saudi Arabia

Taif rose (Rosa damascena trigintipetala Dieck) is a sort of damask rose, which is considered as one of the most important economic products of Taif. In this study, the authors investigated the possible cytotoxic, genotoxic, antimutagenic and anticancer effect of concrete and absolute rose oils. The results showed that both concrete and absolute rose oils were cytotoxically and genotoxically safe at a dose of 10 μg/ml when tested on cultures of normal human blood lymphocytes. Also, the results showed significant antimutagenic activity at p < 0.001 for absolute rose oil at the same dose level when tested on cultures of normal human blood lymphocytes supplemented with 300 ng/ml mitomycin C (MMC). On the other hand, concrete and absolute oils exerted a cytotoxic activity against two kinds of human cancer cell lines: HepG2 and MCF7. Concrete oil showed cytotoxic activity against HepG2 and MCF7 with a half maximal inhibitory concentration (IC50) of 16.28 and 18.09 μg/ml, respectively, whereas absolute rose oil showed its cytotoxic activity against HepG2 and MCF7 with an IC50 of 24.94 and 19.69, respectively. From this study, it is concluded that concrete and absolute rose oils are cytotoxically and genotoxically safe at a dose of 10 μg/ml when tested on cultures of normal human blood lymphocytes. In addition, absolute oil has an antimutagenic activity at the same dose. Further investigations are needed to study the activity of higher doses of both oils in vitro and in vivo in experimental animals in order to evaluate the capability of using these oils as therapeutic for treatment of some kinds of cancers.

Differences in the hydroxylation pattern of flavonoids alter their chemoprotective effect against direct- and indirect-acting mutagens

The antimutagenicity of ten flavonoids, differing in their hydroxylation patterns against direct-acting and indirect-acting mutagens, namely 4-nitro-o-phenylenediamine, sodium azide, mitomycin C, benzo[a]pyrene, aflatoxin B1 and 2-aminofluorene, were compared with the aim of investigating how the hydroxyl groups in their structures govern the biological activity of flavonoids, by the Ames test, with Salmonella typhimurium strains TA98, TA100 and TA102. The flavonoids tested were: quercetin, kaempferol, luteolin, fisetin, chrysin, galangin, flavone, 3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone. In these tests, all compounds were shown to be antimutagenic in more than one strain and various mechanisms of action were demonstrated. The results suggested that the number and position of hydroxyl groups may increase or decrease the protective effect, depending on the type and concentration of flavonoids and mutagen used. These studies contribute to clarifying the mechanisms by which these flavonoids act in protecting DNA from damage. This is required before they can be widely used.

Mutagenicity and antimutagenicity of (-)-hinokinin a trypanosomicidal compound measured by Salmonella microsome and comet assays

Background

The dibenzylbutyrolactone lignan (−)-hinokinin (HK) was derived by partial synthesis from (−)-cubebin, isolated from the dry seeds of the pepper, Piper cubeba. Considering the good trypanosomicidal activity of HK and recalling that natural products are promising starting points for the discovery of novel potentially therapeutic agents, the aim of the present study was to investigate the (anti) mutagenic∕ genotoxic activities of HK.

Methods

The mutagenic∕ genotoxic activities were evaluated by the Ames test on Salmonella typhimurium strains TA98, TA97a, TA100 and TA102, and the comet assay, so as to assess the safe use of HK in the treatment of Chagas’ disease. The antimutagenic ∕antigenotoxic potential of HK were also tested against the mutagenicity of a variety of direct and indirect acting mutagens, such as 4- nitro-o-phenylenediamine (NOPD), sodium azide (SA), mitomycin C (MMC), benzo[a]pyrene (B[a]P), aflatoxin B₁ (AFB₁), 2-aminoanthracene (2-AA) and 2-aminofluorene (2-AF), by the Ames test, and doxorubicin (DXR) by the comet assay.

Results

The mutagenicity∕genotoxicity tests showed that HK did not induce any increase in the number of revertants or extent of DNA damage, demonstrating the absence of mutagenic and genotoxic activities. On the other hand, the results on the antimutagenic potential of HK showed a strong inhibitory effect against some direct and indirect-acting mutagens.

Conclusions

Regarding the use of HK as an antichagasic drug, the absence of mutagenic effects in animal cell and bacterial systems is encouraging. In addition, HK may be a new potential antigenotoxic ∕ antimutagenic agent from natural sources. However, the protective activity of HK is not general and varies with the type of DNA damage-inducing agent used.

Comparative Studies of the (Anti) Mutagenicity of Baccharis dracunculifolia and Artepillin C by the Bacterial Reverse Mutation Test

Baccharis dracunculifolia is a plant native from Brazil, commonly known as ‘Alecrim-do-campo’ and ‘Vassoura’ and used in alternative medicine for the treatment of inflammation, hepatic disorders and stomach ulcers. Previous studies reported that artepillin C (ArtC, 3-{4-hydroxy-3,5-di(3-methyl-2-butenyl)phenyl}-2(E)-propenoic acid), is the main compound of interest in the leaves. This study was undertaken to assess the mutagenic effect of the ethyl acetate extract of B. dracunculifolia leaves (Bd-EAE: 11.4–182.8 µg/plate) and ArtC (0.69–10.99 µg/plate) by the Ames test using Salmonella typhimurium strains TA98, TA97a, TA100 and TA102, and to compare the protective effects of Bd-EAE and ArtC against the mutagenicity of a variety of direct and indirect acting mutagens such as 4-nitro-O-phenylenediamine, sodium azide, mitomycin C, benzo[a]pyrene, aflatoxin B1, 2-aminoanthracene and 2-aminofluorene.The mutagenicity test showed that Bd-EAE and ArtC did not induce an increase in the number of revertant colonies indicating absence of mutagenic activity. ArtC showed a similar antimutagenic effect to that of Bd-EAE in some strains of S. typhimurium, demonstrating that the antimutagenic activity of Bd-EAE can be partially attributed to ArtC. The present results showed that the protective effect of whole plant extracts is due to the combined and synergistic effects of a complex mixture of phytochemicals, the total activity of which may result in health benefits.

Antimutagenic and free radical scavenger effects of leaf extracts from Accacia salicina

Background

Three extracts were prepared from the leaves of Accacia salicina; ethyl acetate (EA), chloroform (Chl) and petroleum ether (PE) extracts and was designed to examine antimutagenic, antioxidant potenty and oxidative DNA damage protecting activity.

Methods

Antioxidant activity of A. salicina extracts was determined by the ability of each extract to protect against plasmid DNA strand scission induced by hydroxyl radicals. An assay for the ability of these extracts to prevent mutations induced by various oxidants in Salmonella typhimurium TA102 and TA 104 strains was conducted. In addition, nonenzymatic methods were employed to evaluate anti-oxidative effects of tested extracts.

Results

These extracts from leaf parts of A. salicina showed no mutagenicity either with or without the metabolic enzyme preparation (S9). The highest protections against methylmethanesulfonate induced mutagenicity were observed with all extracts and especially chloroform extract. This extract exhibited the highest inhibitiory level of the Ames response induced by the indirect mutagen 2- aminoanthracene. All extracts exhibited the highest ability to protect plasmid DNA against hydroxyl radicals induced DNA damages. The ethyl acetate (EA) and chloroform (Chl) extracts showed with high TEAC values radical of 0.95 and 0.81 mM respectively, against the ABTS^.+.

Conclusion

The present study revealed the antimutagenic and antioxidant potenty of plant extract from Accacia salicina leaves.