Structure-activity relationships of derivatives of fusapyrone, an antifungal metabolite of Fusarium semitectum

Fusapyrone (1) and deoxyfusapyrone (2) are two 3-substituted-4-hydroxy-6-alkyl-2-pyrones isolated from Fusarium semitectum that have considerable antifungal activity against molds. Because of their low zootoxicity and selective action they are potentially utilizable along with biocontrol yeasts for control of postharvest crop diseases. Seven derivatives of 1 (3 and 5-10) and one derivative of 2 (4) were obtained by chemical modifications of the glycosyl residue, the 2-pyrone ring, the aliphatic chain, or a combination thereof, and a structure-activity correlation study was carried out with regard to their zootoxicity and antifungal activity. Derivatives 7-10, as well as 1, were slightly zootoxic in Artemia salina (brine shrimp) bioassays, whereas pentaacetylation of 1 into 3, 5, and 6 resulted in a strong increase in toxicity. Compound 4, the tetraacetyl derivative of 2, was as toxic as 2. Because the structural changes of 1 that resulted in an increase of biological activity in A. salina bioassay were those that affected mainly the water solubility of the molecule, it appears that toxicity is related to hydrophobicity. Compounds 1 and 2 showed strong antifungal activity toward Botrytis cinerea, Aspergillus parasiticus, and Penicilliun brevi-compactum (minimum inhibitory concentration at 24 h = 0.78-6.25 microg/mL). Among derivatives 3-10, only compounds 7, 9, and 10 retained some activity, limited to B. cinerea and at high concentration (25-50 microg/mL). None of the compounds 1-10 inhibited the growth of the biocontrol yeasts Pichia guilliermondii and Rhodotorula glutinis at the highest concentration tested (50 microg/mL).     

Metabolite profiling of grape: Flavonols and anthocyanins

Flavonols are products of the flavonoid biosynthetic pathway, which also give rise to anthocyanins and condensed tannins in grapes. We investigated their presence in the berry skins of 91 grape varieties (Vitis vinifera L.), in order to produce a classification based on the flavonol profile. The presence of laricitrin 3-O-galactoside and syringetin 3-O-galactoside in red grapes is reported here for the first time. In red grapes, the main flavonol was quercetin (mean = 43.99%), followed by myricetin (36.81%), kaempferol (6.43%), laricitrin (5.65%), isorhamnetin (3.89%), and syringetin (3.22%). In white grapes, the main flavonol was quercetin (mean = 81.35%), followed by kaempferol (16.91%) and isorhamnetin (1.74%). The delphinidin-like flavonols myricetin, laricitrin, and syringetin were missing in all white varieties, indicating that the enzyme flavonoid 3',5'-hydroxylase is not expressed in white grape varieties. The pattern of expression of flavonols and anthocyanins in red grapes was compared, in order to gain information on the substrate specificity of enzymes involved in flavonoid biosynthesis.     

Performance,Capability and Costs of Small-Scale Cable Yarding Technology

The authors tested two mini-yarders, one for uphill and the other for downhill extraction. The two machines were modern commercial models, offering state-of-the-art yarding technology on a miniature scale and at a much lower cost than required for purchasing a full-size tower yarder. The two units must not be regarded as alternative, but rather as complementary, since they offer different capabilities and advantages. Both machines were tested while harvesting firewood from the thinning of young beech stands in Central Italy. The tests indicated that both units can reach a productivity between 1.5 and 2.4 m³ SMH⁻¹, including all delays, as well as set-up and dismantle time. Calculated extraction cost ranged between 24 and over 30€ m⁻³. The authors calculated a set of regression equations for estimating machine productivity as a function of the main work conditions. The performance of the studied mini-yarders does not seem much inferior to that achieved by professional light tower yarder under the same work conditions, but the lighter construction of the small-scale units may result in a lower resistance to wear and abuse. In any case, mini-yarders seem ideal for deployment under the typical conditions of small-scale forestry, offering a good solution to wood extraction on steep terrain, competitive with animal and winch logging in terms of productivity, cost and operator comfort.     

Performance and cost of a new mini-forwarder for use in thinning operations

Two tests were conducted with a new model of mini-forwarder, specifically designed for thinning operations. The tested machine resembles a conventional industrial forwarder, with tandem bogies and central articulation, but is much smaller and lighter. The machine was tested on forest plantations established on ex-farm land: such plantations offer favorable and homogeneous work conditions, which allowed reasonably accurate productivity figures to be obtained with a relatively small number of observation hours (about 10.5 h). Despite the relative inexperience of the driver, the tests indicated a productivity of between 3.1 and 3.8 m³ per scheduled machine hour (SMH) over an extraction distance of about 400 m. Extraction costs ranged from 12.4 to 15.1 € m⁻³ at the calculated machine rate of 47.6 € h⁻¹. Compared to older models derived from recreation vehicles or tracked wheelbarrows, the machine tested in this study offers a better performance and a much more comfortable workplace, with the operator sitting inside an enclosed and insulated cab. Fitted with four bogies and provided with a much longer wheelbase, the new forwarder is likely to be safer than tracked machines when surmounting obstacles, and it certainly offers a much smoother ride to the operator. Nevertheless, the tested machine is still much narrower than industrial forwarders and does not enjoy the same lateral stability. Hence, the machine is ideal for sneaking between trees and climbing over obstacles, but once on a slope it must be driven straight along the grade and never across it, unless with much caution. Like all hydrostatically driven vehicles, the tested mini-forwarder is not suited to long-distance extraction (>1 km): if run at high speed for too long, its hydrostatic transmission tends to overheat, forcing the operator to make frequent stops.     

Matrix Production,Pigment Synthesis,and Sporulation in a Marine Isolated Strain of Bacillus pumilus

The ability to produce an extracellular matrix and form multicellular communities is an adaptive behavior shared by many bacteria. In Bacillus subtilis, the model system for spore-forming bacteria, matrix production is one of the possible differentiation pathways that a cell can follow when vegetative growth is no longer feasible. While in B. subtilis the genetic system controlling matrix production has been studied in detail, it is still unclear whether other spore formers utilize similar mechanisms. We report that SF214, a pigmented strain of Bacillus pumilus isolated from the marine environment, can produce an extracellular matrix relying on orthologs of many of the genes known to be important for matrix synthesis in B. subtilis. We also report a characterization of the carbohydrates forming the extracellular matrix of strain SF214. The isolation and characterization of mutants altered in matrix synthesis, pigmentation, and spore formation suggest that in strain SF214 the three processes are strictly interconnected and regulated by a common molecular mechanism.     

Jellyfish as an Alternative Source of Bioactive Antiproliferative Compounds

Jellyfish are commonly considered a nuisance for their negative effects on human activities (e.g., fisheries, power plants and tourism) and human health. However, jellyfish provide several benefits to humans and are commonly eaten in eastern countries. Additionally, recent studies have suggested that jellyfish may become a source of high-value molecules. In this study, we tested the effects of the methanolic extracts and enriched fractions, obtained by solid-phase extraction fractionation, from the scyphomedusae Pelagia noctiluca, Rhizostoma pulmo, Cotylorhiza tuberculata and the cubomedusa Caryddea marsupialis on different human cancer cell lines in order to evaluate a potential antiproliferative activity. Our results indicated that fraction C from Caryddea marsupialis-(CM) and C. tuberculata oral arms (CTOA) were the most active to reduce cell viability in a dose-dependent manner. LC/MS based dereplication analyses highlighted that both bioactive fractions contained mainly fatty acids and derivatives, with CM additionally containing small peptides (0.7–0.8 kDa), which might contribute to its higher biological activity. The mechanism of action behind the most active fraction was investigated using PCR arrays. Results showed that the fraction C of CM can reduce the expression of genes involved in apoptosis inhibition in melanoma-treated cells, which makes jellyfish a potential new source of antiproliferative drugs to be exploited in the future.     

Kisspeptin in the early post–partum of the dairy cow

Recently, a new molecule, kisspeptin (Kp), and in particular Kisspeptin 10 (Kp10), was implicated in stimulating the hypothalamic–pituitary–gonadal axis. The aim of this study was to evaluate circulating Kp10 levels in the early post–partum period of the dairy cow. Blood samples were collected from 40 dairy cows, at 10 (T10), 12 (T12), 14 (T14) and 16 (T16) days after calving. Progesterone (P4) levels were evaluated using ELISA, and levels of oestrogens (E2) and Kp were evaluated using a radio‐immunologic method. After an initial plateau, Kp10 significantly increased at T14 and decreased at T16. The P4 and E2 mean serum values remained in the physiological range. It is likely that Kp10 enhanced hypothalamic GnRH release as well as pituitary gonadotropin secretion, thus promoting follicular growth and the increase in E2 levels, which might have further enhanced Kp10 release through a positive feedback loop. To our best knowledge, this is the first report on the range of Kp10 blood concentration during the early post–partum period in the dairy cow. The results of our study will increase our current understanding of the complex neuro‐endocrine crosstalk underlying the resumption of ovarian cyclicity in the dairy cow.     

Characterization and pathogenicity of Pestalotiopsis uvicola causing black leaf spot on carob (Ceratonia siliqua L.) in Italy

During spring 2013, several carob plants (Ceratonia siliqua L.), showing symptoms of necrotic black lesions on leaves, were observed in Capri Island, Southern Italy. Acervuli, producing conidia with septa and appendages, appeared in the centre of the lesions. In this report, the identification of the causal agent of this disease was made applying Koch’s postulates. Morphological characteristics of colony (colour and mycelium appearance) and conidia (size, shape, number of septa, length and number of apical and basal appendages) were characterized to identify the pathogen. Moreover, for a rapid and unambiguous identification of the fungal species, the internal transcribed spacers, comprising the 5.8 rDNA gene (ITS1-5.8-ITS2), were amplified by PCR, using the genomic DNA extracted from the isolated colonies, and sequenced. The fungus isolated was ascribed to the species Pestalotiopsis uvicola (Speg.) Bissett. Phylogenetic analysis, performed with sequences present in GenBank database, showed that carob isolates clustered with P. uvicola isolates from North America and Italy, separately from Australian, Indian and Chinese isolates. P. uvicola isolates were pathogenic when artificially inoculated on carob leaves. To the best of our knowledge, this is the first report of P. uvicola on carob.     

Analytical discrimination of poisonous and nonpoisonous chemotypes of giant fennel (Ferula communis L.) through their biologically active and volatile fractions

Giant fennel (Ferula communis L.) from Sardinia is characterized by two chemotypes with different biological activities. One chemotype is poisonous, due to prenylcoumarins, and responsible for ferulosis, which mainly affects sheep and goats, cattle, and horses; the other chemotype is nonpoisonous and contains daucane esters. The two chemotypes cannot be distinguished botanically. High-performance liquid chromatography-diode array-ultraviolet detection-mass spectrometry (HPLC-DAD-UV-MS) analysis of the composition of the fractions containing the biologically active metabolites and of the volatile fractions, by gas chromatography-mass spectrometry (GC-MS), of both essential oil and headspace sampled by headspace solid-phase microextraction (HS-SPME) are here shown to be effective in discriminating the poisonous and nonpoisonous chemotypes. HS-SPME with CAR/PDMS/DVB in combination with GC-MS has also been found to be a successful, fully automated one-step method for rapid and unequivocal discrimination of the two chemotypes, using aristolene and allohedycaryol as markers of the poisonous and nonpoisonous chemotypes, respectively.