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The phytotoxic effect of some tree species could act as an ecological filter through chemical production that influences plant growth of other species. Despite this widespread interest, few studies have investigated the allelopathic effect of some Moraceae species, while this mechanism has not been studied in Ficus carica. To address this research, we attempted to identify the allelopathic mechanisms of thirteen local preserved fig cultivars on the germination and seedling growth of common weeds and standard target species. The results stated that all fig extracts displayed significant phytotoxic impact, and the degree of inhibition was appeared to be dependent on the cultivars and target species. In general, leaf extracts were more toxic and significantly influenced the seedling elongations, as compared to twig extracts. It was clearly marked that the germination and growth of weed species were totally affected by leaf aqueous and methanol extracts of cultivars Kahli and Bouhouli, respectively, at 40 g/L and 6 g/L. The phytochemical analysis through high performance liquid chromatography detected similar profile among cultivars but with a significant disparity in phenolic composition. Among the identified compounds, rutin is the major flavonoid compound recorded in cv. Zidi and was highly accumulated in leaf rather than in twig. It was obvious that the different fig cultivars or even their tissues can be characterized and clustered in three groups based on their allelopathic potential and phenolic compounds.

The metabolic processes involved in fig production are influenced by macro- and micronutrients supply to the trees during the growing season. Potassium is an essential plant nutrient that influences growth and fruit quality. In this study, the effect of foliar potassium sulphate (K2SO4) application on biochemical composition and antioxidant activity of fig was assessed in cv. Bouhouli, a commonly cultivated cultivar in Djebba (Northwest of Tunisia). Foliar potassium sulphate supply at 2% on Bouhouli trees were applied twice during the fruit growth. Results exhibited that potassium fertilization induces a significant change in total phenolic, flavonoid contents and radical scavenging activity in total fruit and achenes compared to the control. A strong correlation was observed between antioxidant activity and different phenolic compounds. The total fruit and achenes methanol extracts possess, respectively, the highest values of polyphenol by 29.3 and 25.1 mg GAE/g DW compared to the control. Similarly, the flavonoids content was increased in methanol extracts, respectively, by 36 and 48%. HPLC analyses revealed the influence of potassium on concentrations of phenolic compounds in fig sprayed with K2SO4. Among the polyphenols, the chlorogenic acid, cyanidin 3-rutinoside and cyanidin 3,5-diglucoside contents increased from 0.87 to 1.70 mg/g DW under potassium spray, whereas those compounds were not detected in fig achenes. The present study provides clear evidence that potassium sulphate can be used to manipulate total phenolic concentrations in fig with strong antioxidant potential that could be benefits to human health. Thus, potassium sulphate application at 2% could improve nutritional and qualitative attributes of fig.

To integrate the understanding of mycological biodeterioration on artistic-historical heritage, we cultivated Alternaria tenuissima on Neapolitan Yellow Tuff (NYT) tiles for 20 d in a low-carbon environment. The fungus, collected within the UNESCO site of ancient Oplontis ruins (Naples, Italy), was monitored during its early colonization both for the epilithic and the cryptoendolithic growth by using photomicrography-based image analyses. The data were integrated with the count of conidia and the analysis of biochemical proxies in order to evaluate the biological status of the fungus during growth. Additionally, we provided novel and synthetic insights on A. tenuissima 3D growth dynamics, suggesting that visible fungal spots on stone monuments could represent the “iceberg tip” for advanced stone decay. Our results confirm that in vitro tests, coupled with microscopical observations and computer image analysis, are useful tools to evaluate and quantify fungal biomass on a stone substratum, especially in the early steps of fungal colonization.

Plant cover and microclimatic conditions can profoundly alter the balance between productivity and decay, with relevant effects on soil carbon (C) and nitrogen (N) pools. Despite their importance, the combined effects of plant cover and microclimatic conditions on soil C and N pools have been poorly assessed, especially in the Mediterranean environment. Therefore, the aims of the present study were to assess how, in Mediterranean areas, C and N pools differ between afforested pine forests and natural shrublands and to highlight the different impacts of plant cover on C and N sequestration at low and high elevations Along a forest floor-mineral soil continuum, plant cover and elevation effects were evaluated through measurements of C and N pools and water-soluble fractions, molecular characterization by 13C and 1H NMR, and microbial and fungal amounts and activities. Our data show that C accumulated more in afforested pine forest soils than in shrubland soils, especially at low elevations. In pine forests, the higher content of aromatic and O alkyl compounds in the upper organic layers and the abundance of aromatic and carboxylic components in the soluble fraction suggest a greater stability of soil organic matter than in shrublands. Additionally, the high concentration of N in the upper organic layer and its reduction in the fermentative layer stimulate soil C accumulation mainly in pine forests at low elevations. The abundant organic mass at high elevations in pine forests improves microbial growth, whereas the greater recalcitrance of organic residues at low elevations in pine forests leads to a decrease in the bacterial component compared with the fungal component. In conclusion, the plant cover effect appears to be strongly conditioned by elevation, and afforestation with pine at low elevations could favour long-term soil C storage.

Sartans are chemical compounds with antagonistic action towards the AT1 receptors of angiotensin II, a multifunctional peptide with vasoconstrictor action and one of the main peptides responsible for regulating blood pressure. Losartan (progenitor of the group), valsartan, irbesartan, candesartan, eprosartan, telmisartan and a few other compounds belong to this class. The use of sartans, introduced in the mid-90s of the last century, has quickly spread mainly due to the alleged reduction in the incidence of certain adverse effects of varying severity (cough, angioedema) associated with the intake of ACE inhibitors. Their very strong commercial success together with their low metabolic degradation and high environmental persistence has consecrated them as emerging pollutants in just 20 years. This review presents a complete picture of sartans in relation to their chemical structure, chemical-physical properties and by-products in aqueous solutions as well as under oxidative and photodegradative conditions, their environmental presence and knowledge known to date and their fate in wastewater treatment plants.

5,5- and 3,5-Diarylfuranones have been obtained in a three-step one-pot manner. The procedure starts from photooxygenation of easily accessible arylfurans followed by in situ base treatment and finally by triflic anhydride mediated acylation of activated aromatic substrates. The regioselectivity of the acylation reaction depends on the reaction conditions and/or activation of both acid and aromatic reagents. The 5,5-diarylfuranone products have the same carbon skeleton as some rearranged tetrahydrofuran lignans.

Careful 2D-NMR analyses of phenylphenalenes and dimeric phenylphenalenes isolated from Eichhornia crassipes allowed to revise the structure of five of them.

Examination of the hydroalcoholic extract of the leaves of Aptenia cordifolia has afforded three cinnamic acid amides and two lignanamides. Structures were established on the basis of spectroscopic data, including 2D-NMR analyses.

Investigation of the ethyl acetate extract of Juncus acutus rhizomes revealed seven benzocoumarins, probably derived from oxidation of phenanthrenes already isolated from the plant. The structures were determined by means of spectroscopic methods. The anti- algal activity of the isolated compounds tested on the green alga Pseudokirchneriella subcapitata are reported here. q 2003 Elsevier Science Ltd. All rights reserved.

Two new compounds identified as methyl derivatives of phenyl naphthalenedicarboxylic acid and phenyl naphthalenecarboxylic acid linked to a phenylphenalene unit were isolated from the extract of Eichhornia crassipes (water hyacinth). The structures have been determined on the basis of spectroscopic analyses, mainly using 2D NMR techniques.