Synthesis, Production, and Biotechnological Applications of Exopolysaccharides and Polyhydroxyalkanoates by Archaea

Extreme environments, generally characterized by atypical temperatures, pH, pressure, salinity, toxicity, and radiation levels, are inhabited by various microorganisms specifically adapted to these particular conditions, called extremophiles. Among these, the microorganisms belonging to the Archaea domain are of significant biotechnological importance as their biopolymers possess unique properties that offer insights into their biology and evolution. Particular attention has been devoted to two main types of biopolymers produced by such peculiar microorganisms, that is, the extracellular polysaccharides (EPSs), considered as a protection against desiccation and predation, and the endocellular polyhydroxyalkanoates (PHAs) that provide an internal reserve of carbon and energy. Here, we report the composition, biosynthesis, and production of EPSs and PHAs by different archaeal species

Cyclic dipeptides produced by marine sponge-associated bacteria as quorum sensing signals.

Four bacterial strains belonging to the genera Vibrio, Pseudoalteromonas and Photobacterium were isolated from the marine sponges Dysidea avara and Geodia cynodium. A Bacillus strain was isolated from Ircinia variabilis. A screening of molecules involved in quorum sensing (QS) was carried out by TLC-overlay and a new "plate T-streak" test. To analyze quorum quenching (QQ), a plate T-streak was performed with Chromobacterium violaceum. Strains of Vibrio isolated from both marine sponges and a strain of Photobacterium isolated from G. cynodium, activated QS bioreporters. A strain of Pseudoalteromonas isolated from D. avara showed QQ activity. Finally, it is reported that cyclic dipeptides isolated from strains of Vibrio sp. and Bacillus sp. (isolated from D. avara and I. variabilis, respectively) were involved in the QS mechanism. The simultaneous presence of bacteria that showed contrasting responses in bioassays for QS signal molecule synthesis in marine sponges could add an interesting dimension to the signalling interactions which may be happening in sponges

The waste- based biorefinery for the sustainable production of energy and value added molecules

The vegetable waste biomass is produced by several production chains like agriculture, agro- and food industries. Such biomass represents the renewable feedstock for a waste-based biorefinery, an industrial model that plays a key role in a bio-economy system, an innovative economy model that is based on the sustainable use of renewable resources in agriculture and industry, and that takes in account biodiversity and environmental protection (1). In this frame, the identification of starting materials that are not in competition with food chain or other production chains coupled with the development of new technologies and processes, is one of the main issues for a waste- based biorefinery. Here we reported some examples for the re-use and valorization of two kinds of vegetable waste biomass: the energy crops’ residues (2, 3) and the wastes of food industry (4, 5) The crops selected, i.e. the giant reed (Arundo donax) and the cardoon (Cynara cardunculus) are among the annual crops and perennial herbaceous species that are object of increasing interest in relation to their use as feedstock for lignocellulose-based biorefinery. The food wastes that have been investigated include the residues of the industrial transformation of tomato, lemon, carrot and fennel, i.e. some most typical cultivation of the Italian agro-industrial sector. This two types of waste biomass have been investigated for their potential as sources of value added molecules and bioenergy

Productivity and Nutritional Trait Improvements of Different Tomatoes Cultivated with Effective Microorganisms Technology

The use of ecofriendly strategies, such as the use of Plant Growth Promoting Bacteria, to improve the yield and quality of crops has become necessary to satisfy the growing demand of food and to avoid the use of chemical fertilizers and pesticides. In this study, we report the effects of an innovative microbial inoculation technique, namely Effective Microorganisms (EM), compared with traditional approaches, on productivity and nutritional aspect of four tomato varieties: Brandywine, Corbarino Giallo, S. Marzano Cirio 3, S. Marzano Antico. Results showed an increase of plant productivity as well as an enhanced antioxidant activity mainly in San Marzano Antico and Brandywine varieties treated with EM technology. Moreover, the polyphenol and carotenoid contents also changed, in response to the plant treatments. In conclusion, the application of EM® technology in agriculture could represent a very promising strategy in agricultural sustainability

Identification of N-Hexadecanoyl-L-homoserine lactone (C16-AHL) as signal molecule in halophilic bacterium Halomonas smyrnensis AAD6

n/

ANTIOXIDANT AND ANTIPROLIFERATIVE ACTIVITIES OF DIFFERENT CULTIVARS OF TOMATOES (LYCOPERSICON ESCULENTUM) ON TUMORAL CELL LINES

To increase the knowledge about the biological properties of tomatoes, the antioxidant and antiproliferative activities of extracts of nine cultivars of Lycopersicon esculentum, as well as their chemical composition, were studied. The highest antioxidant capacity has been revealed in San Marzano Cirio 3 and Pomodoro Giallo cultivars, both in hydrophilic and lipophilic fractions, while San Marzano, Corbarino di Corbara, and Pomodoro Giallo exhibited the best radical scavenger activity in methanolic fraction. As regards the antiproliferative activity, the median inhibition concentrations of the lipophilic extracts ranged from 272.3 (Pomodoro Giallo) to 364.4 (Corbarino di Corbara) mg dried extract L-1 on Hep-G2 and from 324.6 (San Marzano Cirio 3) to 455.4 (Nero di Sicilia) on Caco-2. The methanolic extracts were more active on Caco-2 than Hep-G2, while the hydrophilic extracts were not active. These biological properties could be ascribed to the identified carotenoids and phenolic acids as well as to a pull of minor compounds exerting their synergistic effect