Potential of Lactobacillus casei , Culture Permeate, and Lacti Acid To Control Microorganisms in Ready-To-Use Vegetables.

The effects of various treatments (i.e., the addition of a strain of Lactobacillus that produces antimicrobial agents, Lactobacillus casei IMPC LC34, its sterile permeate, and 0.5 or 1% lactic acid) on the growth of microorganisms associated with ready-to-use mixed salad vegetables were compared during refrigerated (8°C) storage. The addition of 3% culture permeate to mixed salads reduced the total mesophilic bacteria counts from 6 to 1 log CFU/g, and suppressed coliforms, enterococci, and Aeromonas hydrophila after 6 days of storage at 8°C. A similar effect was shown when the L. casei culture was inoculated in the vegetables. One percent lactic acid had a bacteriostatic effect on the bacterial groups examined, except for total and fecal coliforms, which were reduced by about 2 and 1 log unit, respectively, while 0.5% lactic acid did not affect the indigenous microflora of the vegetables. The potential of these new hurdles to prevent the growth of spoilage and pathogenic bacteria in ready-to-use salad vegetables is suggested

The cultivation of Castanea sativa (Mill.) in Europe, from its origin to its diffusion on a continental scale

The history of Castanea sativa (sweet chestnut) cultivation since medieval times has been well described on the basis of the very rich documentation available. Far fewer attempts have been made to give a historical synthesis of the events that led to the cultivation of sweet chestnut in much earlier times. In this article we attempt to reconstruct this part of the European history of chestnut cultivation and its early diffusion by use of different sources of information, such as pollen studies, archaeology, history and literature. Using this multidisciplinary approach, we have tried to identify the roles of the Greek and Roman civilizations in the dissemination of chestnut cultivation on a European scale. In particular, we show that use of the chestnut for food was not the primary driving force behind the introduction of the tree into Europe by the Romans. Apart from the Insubrian Region in the north of the Italian peninsula, no other centre of chestnut cultivation existed in Europe during the Roman period. The Romans may have introduced the idea of systematically cultivating and using chestnut. In certain cases they introduced the species itself; however no evidence of systematic planting of chestnut exists. The greatest interest in the management of chestnut for fruit production most probably developed after the Roman period and can be associated with the socio-economic structures of medieval times. It was then that self-sufficient cultures based on the cultivation of chestnut as a source of subsistence were forme

Suitability of the nisin Z-producer lactococcus lactis subsp. lactis CBM 21 to be used as an adjunct culture for squacquerone cheese production

This research investigated the technological and safety effects of the nisin Z producer Lactococcus lactis subsp. lactis CBM 21, tested as an adjunct culture for the making of Squacquerone cheese in a pilot-scale plant. The biocontrol agent remained at a high level throughout the cheese refrigerated storage, without having a negative influence on the viability of the conventional Streptococcus thermophilus starter. The inclusion of CBM 21 in Squacquerone cheesemaking proved to be more effective compared to the traditional one, to reduce total coliforms and Pseudomonas spp. Moreover, the novel/innovative adjunct culture tested did not negatively modify the proteolytic patterns of Squacquerone cheese, but it gave rise to products with specific volatile and texture profiles. The cheese produced with CBM 21 was more appreciated by the panelists with respect to the traditional one

Low-resolution structural studies of human Stanniocalcin-1

Background: Stanniocalcins (STCs) represent small glycoprotein hormones, found in all vertebrates, which have been functionally implicated in Calcium homeostasis. However, recent data from mammalian systems indicated that they may be also involved in embryogenesis, tumorigenesis and in the context of the latter especially in angiogenesis. Human STCI is a 247 amino acids protein with a predicted molecular mass of 27 kDa, but preliminary data suggested its di- or multimerization. The latter in conjunction with alternative splicing and/or post-translational modification gives rise to forms described as STC(50) and "big STC", which molecular weights range from 56 to 135 kDa. Results: In this study we performed a biochemical and structural analysis of STCI with the aim of obtaining low resolution structural information about the human STCI, since structural information in this protein family is scarce. We expressed STCI in both E. coli and insect cells using the baculo virus system with a C-terminal 6 x His fusion tag. From the latter we obtained reasonable amounts of soluble protein. Circular dichroism analysis showed STCI as a well structured protein with 52% of alpha-helical content. Mass spectroscopy analysis of the recombinant protein allowed to assign the five intramolecular disulfide bridges as well as the dimerization Cys202, thereby confirming the conservation of the disulfide pattern previously described for fish STCI. SAXS data also clearly demonstrated that STCI adopts a dimeric, slightly elongated structure in solution. Conclusion: Our data reveal the first low resolution, structural information for human STCI. Theoretical predictions and circular dichroism spectroscopy both suggested that STCI has a high content of alpha-helices and SAXS experiments revealed that STCI is a dimer of slightly elongated shape in solution. The dimerization was confirmed by mass spectrometry as was the highly conserved disulfide pattern, which is identical to that found in fish STCI

Central domain deletions affect the SAXS solution structure and function of Yeast Hsp40 proteins Sis1 and Ydj1

Background: Ydj1 and Sis1 are structurally and functionally distinct Hsp40 proteins of the yeast cytosol. Sis1 is an essential gene whereas the ydj1 gene is essential for growth at elevated temperatures and cannot complement sis1 gene deletion. Truncated polypeptides capable of complementing the sis1 gene deletion comprise the J-domain of either Sis1 or Ydj1 connected to the G/F region of Sis1 (but not Ydj1). Sis1 mutants in which the G/F was deleted but G/M maintained were capable of complementing the sis1 gene deletion. Results: To investigate the relevance of central domains on the structure and function of Ydj1 and Sis1 we prepared Sis1 constructs deleting specific domains. The mutants had decreased affinity for heated luciferase but were equally capable of stimulating ATPase activity of Hsp70. Detailed low resolution structures were obtained and the overall flexibility of Hsp40 and its mutants were assessed using SAXS methods. Deletion of either the G/M or the G/M plus CTDI domains had little impact on the quaternary structure of Sis1 analyzed by the SAXS technique. However, deletion of the ZFLR-CTDI changed the relative position of the J-domains in Ydj1 in such a way that they ended up resembling that of Sis1. The results revealed that the G/F and G/M regions are not the only flexible domains. All model structures exhibit a common clamp-like conformation. Conclusions: Our results suggest that the central domains, previously appointed as important features for substrate binding, are also relevant keeping the J-domains in their specific relative positions. The clamp-like architecture observed seems also to be favorable to the interactions of Hsp40 with Hsp70

Differences in the Volatile Profile of Apple Cider Fermented with Schizosaccharomyces pombe and Schizosaccharomyces japonicus

In this study, two strains of Schizosaccharomyces pombe (NCAIM Y01474(T) and SBPS) and two strains of Schizosaccharomyces japonicus (DBVPG 6274(T), M23B) were investigated for their capacity to ferment apple juice and influence the volatile compounds of cider compared to Saccharomyces cerevisiae EC1118. The ethanol tolerance and deacidification capacity of Schizosaccharomyces yeasts could make them potential substitutes for the commonly used S. cerevisiae starter cultures. Despite different time courses (10-30 d), all strains could complete the fermentation process, and Schizosaccharomyces strains reduced the concentration of malic acid in the apple juice. Results indicated that each yeast exerted a distinctive impact on the volatile profile of the apple cider, giving final products separated using a principal component analysis. The volatile composition of the cider exhibited significant differences in the concentration of alcohols, esters, and fatty acids. Particularly, the flocculant strain S. japonicus M23B increased the levels of ethyl acetate (315.44 +/- 73.07 mg/L), isoamyl acetate (5.99 +/- 0.13 mg/L), and isoamyl alcohol (24.77 +/- 15.19 mg/L), while DBVPG 6274(T) incremented the levels of phenyl ethyl alcohol and methionol up to 6.19 +/- 0.51 mg/L and 3.72 +/- 0.71 mg/L, respectively. A large production of terpenes and ethyl esters (e.g., ethyl octanoate) was detected in the cider fermented by S. cerevisiae EC1118. This study demonstrates, for the first time, the possible application of S. japonicus in cider-making to provide products with distinctive aromatic notes"

Design of ideal vibrational signals for stinkbug male attraction through vibrotaxis experiments

Many groups of insects utilize substrate-borne vibrations for intraspecific communication. This characteristic makes them a suitable model for exploring the vibrations as a tool for pest control in alternative to chemicals. The detailed knowledge of the species communication is a prerequisite to select the best signals to use. In this sense, this study aimed at exploring the use of substrate-borne vibrations for pest control of the brown marmorated stink bug (BMSB), Halyomorpha halys Stål (Heteroptera: Pentatomidae). To this purpose, in a first set of experiments, we identified the spectral and temporal characteristics that best elicit male responsiveness. Bioassays were conducted with artificial signals that mimicked the natural female calling signal. In a second part, we used the acquired knowledge to synthesize new signals endowed with different degrees of attractiveness in single and two choice bioassays using a wooden custom-made T stand