Valorisation of the Effects of Bioactive Compounds of the Ethanolic Extract of Ramalina Farinacea (Ramalinaceae) on the Development, Eating and Pupation Behavior of Drosophila Melanogaster (Diptera: Drosophilidae)

Plants are rich in bioactive chemical secondary metabolites and have proven insecticidal activity by killing or repelling insects. In this work, we aim to evaluate the direct and delayed effects of ethanolic plant extracts on the vinegar fly (Drosophila melanogaster). The treatment was performed by ingestion on second instar larvae (L2) to evaluate the impact of the ethanolic extract on development for 15 days and subsequently on the feeding behavior of the larvae. The results of this study indicate a slowing down of pupal growth until the adult stage, at the three concentrations (0.25 µg/ml, 0.5 µg/ml, 1.5 µg/ml, 2 µg/ml) used. The results also showed that after three days of treatment, third instar D. melanogster larvae lost the ability to detect the odors of their nutrient environments. Other numbers of larvae (34 %) do not make a choice in the different tests performed. This study indicates that the ethanolic extract of Ramalina farinacea has a neurotoxic property our results confirmed the presence of toxic secondary metabolites which have bioinsecticidal activities in this extract.

Ability of metal trace elements accumulation by Lichens, Xanthoria parietina and Ramalina farinacea, in Megres area (Setif, Algeria)

The accumulating ability of the atmospheric Metal Trace Elements (MTE) of two lichenic species thalli; Xanthoria parietina and Ramalina farinacea were evaluated in the region of Megres. The recorded concentrations of MTE (Fe, Cu, Mn, Cd, and Pb) were determined by atomic absorption spectrophotometry (AASF). The ability to accumulate MTE in X. parietina thalli is considerably greater than that of the fruticulous lichen R. farinacea in all stations studied. The general pattern of the elements accumulated in the thalli of the two species in decreasing order of their concentrations was Fe> Mn> Pb> Cu> Cd. The Fe values are very high in X. parietina thalli with an average of 35237.5 ± 3394.2 mg/kg dry wt. In contrast, the Pb concentrations are high, especially in the southern station of the Megres region. The results showed that X. parietina is a hyper-accumulating species of MTE, compared to R. farinacea. This work highlights the ecological importance of this species as a stable and resistant pioneer in this fragile region.

Lichens and allied fungi of old parks of three museum-reserves in Moscow Region (Russia)

We present the results of lichenological research in the parks of the museum-reserve Abramtsevo, the museum-reserve of A. S. Pushkin and the museum-estate Ostafyevo – Russian Parnassus, for which no previous data were available. The checklist of lichen biota contains 103 species including 98 lichens, a lichenicolous fungus and 4 non-lichenized fungi. 55 species were found in the park of the museum-reserve Abramtsevo, 58 species in the museum-reserve of A. S. Pushkin (estates Vyazemy – 51 and Zakharovo – 29) and 69 species in the museum-estate Ostafyevo – Russian Parnassus. Lichenochora obscuroides (Ostafyevo) is new for Central Russia. Cladonia macilenta, Evernia prunastri and Usnea hirta (Ostafyevo) are listed in the Red Data Book of Moscow. Parmelina tiliacea (Abramtsevo, Vyazemy), Ramalina farinacea, Usnea dasopoga and U. subfloridana (Abramtsevo) are listed in the Red Data Book of the Moscow Oblast. Chaenotheca chrysocephala, Melanelixia subargentifera, Parmelina tiliacea, Physconia perisidiosa and Ramalina europaea (Ostafyevo) are proposed for inclusion in the next edition of the Red Data Book of Moscow.

Inhibition of NO Biosynthetic Activities during Rehydration of Ramalina farinacea Lichen Thalli Provokes Increases in Lipid Peroxidation

Lichens are poikilohydrous symbiotic associations between a fungus, photosynthetic partners, and bacteria. They are tolerant to repeated desiccation/rehydration cycles and adapted to anhydrobiosis. Nitric oxide (NO) is a keystone for stress tolerance of lichens; during lichen rehydration, NO limits free radicals and lipid peroxidation but no data on the mechanisms of its synthesis exist. The aim of this work is to characterize the synthesis of NO in the lichen Ramalina farinacea using inhibitors of nitrate reductase (NR) and nitric oxide synthase (NOS), tungstate, and NG-nitro-L-arginine methyl ester (L-NAME), respectively. Tungstate suppressed the NO level in the lichen and caused an increase in malondialdehyde during rehydration in the hyphae of cortex and in phycobionts, suggesting that a plant-like NR is involved in the NO production. Specific activity of NR in R. farinacea was 91 μU/mg protein, a level comparable to those in the bryophyte Physcomitrella patens and Arabidopsis thaliana. L-NAME treatment did not suppress the NO level in the lichens. On the other hand, NADPH-diaphorase activity cytochemistry showed a possible presence of a NOS-like activity in the microalgae where it is associated with cytoplasmatic vesicles. These data provide initial evidence that NO synthesis in R. farinacea involves NR.