Mitochondrial genome from the lichenized fungus Peltigera rufescens (Weiss) Humb, 1793 (Ascomycota: Peltigeraceae)

Known colloquially as ‘dog-lichens’ or ‘pelt-lichens’, most species of Peltigera grow on soil and mosses. Some species contribute a significant amount of nitrogen to the environment and have been used as traditional medicines. We analyzed the complete mitochondrial genome of P. rufescens, which is a circular genome 65,199 bp in size and its CG content is 26.7%. It contains 15 protein-coding genes (PCGs), 27 transport RNAs (tRNAs), and 3 ribosomal RNAs (rRNAs). Also, the atp9 gene is present in the genome. We used the complete mitochondrial genome to construct a phylogenetic tree by the Bayesian method, which was consistent with the phylogenetic relationship published for P. membranacea which is closely related to P. rufescens.

Sub-lethal effects of the pesticide imazalil on the earthworm Eisenia andrei: reproduction, cytotoxicity, and oxidative stress

Although considered an emerging contaminant and detected in the environment, the systematic and penetration fungicide imazalil ((RS)-1-(β-allyloxy-2,4-dichlorophenylethyl) imidazole) has received relatively little scientific attention with regard to its possible negative effects in the environment. Only a few toxicological studies have assessed the potential environmental effect of imazalil and its impact on organisms. In this context, the aim of the present study is to evaluate the effects of different concentrations of the pesticide imazalil on the earthworm Eisenia andrei in acute contact and chronic tests in natural soil. Moreover, several endpoints, such as biomass loss or gain, reproduction, behavior, effects on immune system cells, and oxidative stress were also evaluated. Imazalil toxicity to E. andrei was determined by three approaches: a filter paper contact test (0, 0.16, 1.66, 16.6, 166 μg.cm-2), an avoidance (0, 0.1, 1, and 10 mg.kg-1), and a chronic test for 45 days (0, 0.01, 0.1, 1, and 10 mg.kg-1). All organisms exposed to the filter paper contact and chronic tests were submitted to two endpoint analyses: first, coelomic fluid collection by the extrusion method to determine density, viability, and cell type; second, oxidative stress assessments by determining GST and CAT enzymatic activities. This study allows for the conclusion that imazalil does not cause immediate earthworm death after exposure (LC50 > 166 μg.cm-1). However, due to several complementary factors, this compound may compromise earthworm health and lead to death, as E. andrei individuals did not avoid the contaminated soil, thus contributing to longer exposure periods and consequent cumulative damage to their systems. Decreased immunocompetent cellular viability (p < 0.05) and density (p < 0.05) in the chronic test are noteworthy, leading to susceptibility to exogenous factors, as well as irreversible cellular damage provoked by oxidative stress, such as cellular membrane rupture.

Lasallia pustulata lichen as possible natural antigenotoxic, antioxidant, antimicrobial and anticancer agent

The methanol extract of the lichen Lasallia pustulata was tested for genotoxic, antioxidant, antimicrobial and anticancer activities. We did this using a cytokinesis block micronucleus (MN) assay on peripheral blood lymphocytes, by measuring free radical and superoxide anion scavenging activity, reducing power, determining of total phenolic compounds and determining the total flavonoid content, measuring the minimal inhibitory concentration by the broth microdilution method against five species of bacteria and five species of fungi and by using the microculture tetrazolium test on FemX (human melanoma) and LS174 (human colon carcinoma) cell lines. As a result of this study, we found that the methanol extract of L. pustulata did not modify the frequency of the MN and nuclear division index in comparison to untreated cells (p > 0.05). These results revealed that the methanol extract had moderate free radical scavenging activity with IC50 values of 395.56 μg/mL. Moreover, the extract tested had effective reducing power and superoxide anion radical scavenging. The values of the minimum inhibitory concentration against the tested microorganisms ranged from 0.625 to 20 mg/mL. In addition, the extract tested had strong anticancer activity against both cell lines with IC50 values of 46.67 and 71.71 μg/mL.

Investigation of cytotoxic, genotoxic and oxidative properties of carvacrol in human blood cells

Carvacrol (CVC), a major constituent of genera Origanum and Thymus, is such a substance that has attracted attention because of its wide variety of beneficial biological activities such as antibacterial, antifungal, and anticancer effects. However, there are limited data on the cytogenetic and antioxidant effects of CVC in cultured human blood cells. The aim of this study was to investigate for the first time the genetic, oxidative, and cytotoxic effects of CVC in cultured human blood cells ( n = 5). Human blood cells were treated with CVC (0–200 mg/L) for 24 and 48 h and then cytotoxicity detected by lactate dehydrogenase (LDH) release and (3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide) (MTT) assay, while DNA damage was also analyzed by micronucleus (MN) assay, chromosomal aberration (CA) assay and 8-oxo-2-deoxyguanosine (8-OH-dG) level. In addition, biochemical parameters (total antioxidant capacity [TAC] and total oxidative stress [TOS]) were examined to determine the oxidative effects. The results of LDH and MTT assays showed that CVC (at concentrations above 100 mg/L) decreased cell viability. In our in vitro test systems, it was observed that CVC had no mutagenic effects on human lymphocytes. On the other hand, CVC (at 50, 75, and 100 mg/L) treatment caused statistically important ( p < 0.05) increases in TAC and TOS levels (at 150 and 200 mg/L) on human lymphocytes. In conclusion, CVC can be a new resource of therapeutics as recognized in this study with their nonmutagenic and antioxidant features.

In vitro risk assessment of usnic acid

Lichens are symbiotic organisms composed of fungi and algae and are very common in Turkey. Lichen secondary metabolites are mainly phenolic compounds produced by fungal partner of lichen symbiosis. Usnic acid (UA) is one of the most common lichen metabolites, and it was reported that to be effective for a wide range of pharmacological purposes including antiviral, antitumor, and antiprotozoal. However, there are limited data on the genotoxic and antioxidant effects of UA in cultured human peripheral blood cells. Therefore, the aim of this thesis study was to investigate the genetic and oxidative effects of UA in cultured human blood cells ( n = 5). The UA was added into culture tubes at various concentrations (0–200 μg/ml). Chromosomal aberrations (CA) and micronuclei (MN) tests were performed for genotoxic damage influences estimation. In addition, biochemical parameters (total antioxidant capacity (TAC) and total oxidative status (TOS)) were examined to determine oxidative effects. In our in vitro test systems, it was observed that UA had no mutagenic effects on human lymphocytes. Furthermore, our results indicated that low concentrations (1 and 5 μg/ml) of UA caused increases of TAC levels in cultured human blood cells. And, the TOS levels were not changed ( p > 0.05) when all the concentrations (except for 200 μg/ml) of UA were applied. In conclusion, UA can be a new resource of therapeutics as recognized in this study with their nonmutagenic and antioxidant features.

The biochemical and histological effects of lichens in normal and diabetic rats

Oxidative stress plays an important role in causing diabetes; however, no studies have thoroughly reported on the toxic and beneficial effects of lichen extracts in patients with diabetes mellitus (DM). This study covers a previously unrecognized effect of two well-known lichen species Cetraria islandica and Pseudevernia furfuracae in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250–500 mg/kg /day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anaesthetized, and metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of liver was examined using three different staining methods: hematoxylin–eosin (H&E), periodic acid Schiff (PAS), and reticulin and Sudan Black B. Our experimental data showed that increasing doses of C. islandica and P. furfuracae alone did not have any detrimental effects on studied parameters and the malondialdehyde level of liver. C. islandica extract showed positive results for antioxidant capacity compared to doses of P. furfuracae extract. However, the protective effect of C. islandica extract on diabetes-induced disorders and hepatic damages is still unclear. Moreover, unfortunately, animals subjected to DM therapy did not benefit from the usage of increasing lichen doses due to their unchanged antioxidant activity in tissues. The results obtained in present study suggested that C. islandica and P. furfuracae is safe but the power of these is limited because of intensive oxidative stress in liver of type 1 diabetic rats. It is also implied that C. islandica extract is especially suitable for different administration routes in DM animals.

In vitro assessment of cytogenetic and oxidative effects of α-pinene

α-Pinene (α-pinene), a bicyclic monoterpene, is present in the oils of many species of coniferous trees, most notably the pine, and is known for its diverse biological properties such as antimicrobial, anti-inflammatory, antiproliferative and antioxidant. However, there are limited data on the cytogenetic and antioxidant effects of α-pinene in cultured human blood cells (n = 5) for the first time. The purpose of this study was to investigate the genetic, oxidative, and cytotoxic effects of α-pinene in cultured human blood cells (n = 5) for the first time. Human blood cells were treated with α-pinene (0 to 200 mg/L) for 24 and 48 h, and then cytotoxicity was detected by lactate dehydrogenase (LDH) release and (3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide) (MTT) assay, while DNA damage was also analyzed by micronucleus (MN) assay, chromosomal aberration (CA) assay and 8-oxo-2-deoxyguanosine (8-OH-dG). In addition, biochemical parameters (total antioxidant capacity (TAC) and total oxidative stress (TOS)) were examined to determine oxidative effects. The results of LDH and MTT assays showed that α-pinene (at 200 mg/L) decreased cell viability. In our in vitro test systems, it was observed that α-pinene did not cause any statistically important changes in the rates of studied genotoxicity endpoints but dose-dependent alterations were observed in TAC and TOS levels. α-Pinene treatment caused increases in TAC levels (at 25 and 50 mg/L) and decreases in TOS levels (only at 200 mg/L) on human lymphocytes. In conclusion, the findings of the present study confirm for the first time that α-pinene could be a significant source of natural antioxidant compound that may have beneficial health effects.

The effects of Cetraria islandica and Pseudevernia furfuracea extracts in normal and diabetic rats

Lichens are symbiotic organisms composed of a fungus joined to a photosynthesizing partner that can be either an alga or a cyanobacterium. They can be used as a novel bioresource for natural antioxidants. However, there is also a need for further studies to validate the lichens used in medicinal remedies. This study covers a previously unrecognized effects of Cetraria islandica (CIAE) and Pseudevernia furfuracea (PFAE) in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250–500 mg/kg/day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anesthetized, metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of kidney was examined using four different staining methods: hematoxylin–eosin (H&E), periodic acid-Schiff (PAS), Masson trichrome and Congo red. Our experimental data showed that increasing doses of CIAE and PFAE did not have any detrimental effects on the studied parameters and the malondialdehyde level of kidney. CIAE extract showed prominent results compared to doses of PFAE extract for antioxidant capacity. However, the protective effect of CIAE extract was inadequate on diabetes-induced disorders and kidney damages. Moreover, animals subjected to diabetes mellitus (DM) therapy did not benefit unfortunately from the usage of increasing lichen doses due to their unchanged antioxidant activity to tissue. The results obtained in present study suggested that CIAE and PFAE are safe but the power of these is limited because of the intensive oxidative stress in kidney of type 1 diabetic rats. It is also implied that CIAE extract is especially suitable for different administration routes in DM.

Potential anticancer activity of carvone in N2a neuroblastoma cell line

Carvone (CVN) is a monocyclic monoterpene found in the essential oils of Mentha spicata var. crispa (Lamiaceae) and Carum carvi L. (Apiaceae) plants and has been reported to have antioxidant, antimicrobial, anticonvulsant, and antitumor activities. The beneficial health properties of CVN have encouraged us to look into its anticancer activity. To the best of our knowledge, reports are not available on the anticancer activity of CVN in cultured primary rat neuron and N2a neuroblastoma (NB) cells. Therefore, the present study is an attempt toward exploring the potential anticancer activity of CVN, if any, in cultured primary rat neuron and N2a NB cells. Our results indicated that CVN (only at 25 mg/L) treatment led to an increase in the total antioxidant capacity levels in cultured primary rat neuron cells compared with control cells. Also, CVN (at concentrations higher than 100 mg/L) treatment led to an increase in the total oxidative stress levels in both cell types. The mean values of the total scores of cells showing DNA damage (for comet assay) were not found to be significantly different from the control values in both cells (p > 0.05). On the other hand, after 24 h treatment with CVN, 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay showed that CVN application significantly reduced the cell viability rates in both cell types at concentrations higher than 100 mg/L. Summarizing, our data suggest that CVN represents little potential for promising anticancer agent to improve brain tumors therapy.

Role of aqueous Bryoria capillaris (Ach.) extract as a genoprotective agent on imazalil-induced genotoxicity in vitro

In recent years, a number of studies have suggested that lichens might be the easily accessible sources of natural drugs that could be used as a possible food supplement. Extensive research is being carried out to explore the importance of lichen species, which are known to contain a variety of pharmacological active compounds. On the other hand, imazalil (IMA), a commonly used fungicide in both agricultural and clinical domains, is suspected to produce very serious toxic effects in vertebrates. In this context, the antigenotoxic effect of aqueous Bryoria capillaris (Ach.) extract (BCE) was studied against the genotoxic damage induced by IMA on cultured human lymphocytes using chromosomal aberrations (CA) and micronucleus (MN) as cytogenetic parameters. Human peripheral lymphocytes were treated in vitro with varying concentrations of BCE (5, 10, 25, 50 and 100 µg/mL), tested in combination with IMA (336 µg/mL). BCE alone was not genotoxic, and when combined with IMA treatment, it reduced the frequency of CAs and the rates of MN. A clear dose-dependent decrease in the genotoxic damage of IMA was observed, suggesting a genoprotective role of BCE. The results of the present study suggest that this plant extract per se do not have genotoxic potential, but can modulate the genotoxicity of IMA on peripheral human lymphocytes in vitro. In conclusion, our findings may have an important application in the protection of cultured human lymphocyte from the genetic damage and side effects induced by agricultural and medical chemicals that are hazardous to people.

Xanthoria elegans (Link) (lichen) extract counteracts DNA damage and oxidative stress of mitomycin C in human lymphocytes

Several lichen species have been used for medicinal purposes throughout the ages, and they are reported to be effective in the treatment of different disorders including ulcer and cancer. It is revealed that lichens may be easily accessible sources of natural drugs and possible food supplements after their safety evaluations. The main objective in this study was to evaluate the roles of aqueous extracts of Xanthoria elegans (at 25, 50 and 100 μg/ml) upon mitomycin C (MMC; at 10(-7) M) induced genotoxic and oxidative damages in cultured human lymphocytes. X. elegans were collected from the Erzurum and Artvin provinces (in Turkey) during August 2010. After the application of MMC and X. elegans extract (XEE), separate and together, human whole blood cultures were assessed by four genotoxicity end-points including chromosomal aberration, micronucleus, sister chromatid exchange (SCE) and 8-oxo-2-deoxyguanosine (8-OH-dG) assays. In addition, biochemical parameters [total antioxidant capacity (TAC) and total oxidative stress (TOS)] were examined to determine oxidative effects. According to our results, the frequencies of cytogenetic endpoints and 8-OH-dG levels were significantly increased by MMC compared with controls in human peripheral lymphocytes. MMC caused oxidative stress by altering TAC and TOS levels. On the contrary, XEE led to increases of TAC level without changing TOS level. XEE had no genotoxic effect. Furthermore, our findings revealed that MMC induced increases in the mean frequencies of four genotoxic indices were diminished by XEE in dose dependent manner, indicating its protective role towards cells from MMC exerted injury. In conclusion, the results obtained in the present study indicate for the first time that XEE is a potential source of natural antigenotoxicants.