ALPINE FARM SCALE INVESTIGATIONS OF THE RELATIONSHIPS BETWEEN PRODUCTIVE SYSTEM AND QUALITY OF DAIRY PRODUCTS

Alpine dairy farming is shifted from an extensive activity based on pasture and low genetic merit cow to an intensive system with specialized breeds and increasing level of concentrate as a supplement in the diet. As a main consequence, a lower echo-compatibility could determine adverse externalities on environment and quality of dairy products. Considering 18 dairy farming located in the mountain area of Veneto Region (Italy), the Environmental Summarizing Indicator (ESI) was estimated by using agronomic and dairying variables. Results indicated that variability of ESI was manly due to productive performance of dairy cows probably because there was a lack of information in the assessment of pasture characteristics. However, higher level of ESI were closely related to the increase of N-phile species and/or less attractive vegetation for grazing cows, even if the indicator seems to explain only a limited part of the variability of the phenomenon. The increase of ESI values seemed to lead to a loss of nutritive value of milk because of the incidence of health favourable fatty acids was reduced

Use of bovine lymphocytes to assess the immunomodulatory effect of natural extracts

A simple and rapid method based on the in vitro bovine lymphocyte proliferation was developed to assess the immunomodulatory activity of natural compounds extracted from plant and foods. The proliferation of lymphocytes was measured by the MTT [3-(4, 5- dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay. This test was used to measure the immuno-enhancing activity of 2 plant extracts and 2 samples of fermented milk after 48 h of incubation. To evaluate the effect of the cow physiological phase on the assay response, the tests were repeat- ed using lymphocytes taken from non-pregnant dry, pregnant dry and post partum cows. The assay was not affect- ed by the cow physiological phase and the results obtained were comparable. Both plant extracts enhanced lym- phocyte growth, in particular the extract 2 was slightly more potent than extract 1. The fermentation of milk with proteolytic starter cultures, such as FAIR E-63 and LA 2, can generate peptidic compounds from milk protein with potential immunostimulating activity. These samples tested in cell culture inhibited lymphocyte proliferation because they showed an acidic pH of 4.5. However, this bioassay was enough sensitive to detect biological activity of different compounds also at low concentrations

Use of bovine lymphocytes to assess the immunomodulatory effect of natural extracts.

A simple and rapid method based on the in vitro bovine lymphocyte proliferation was developed to assess the immunomodulatory activity of natural compounds extracted from plant and foods. The proliferation of lymphocytes was measured by the MTT [3-(4, 5- dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay. This test was used to measure the immuno-enhancing activity of 2 plant extracts and 2 samples of fermented milk after 48 h of incubation. To evaluate the effect of the cow physiological phase on the assay response, the tests were repeated using lymphocytes taken from non-pregnant dry, pregnant dry and post partum cows. The assay was not affected by the cow physiological phase and the results obtained were comparable. Both plant extracts enhanced lymphocytes growth, in particular the extract 2 was slightly more potent than extract 1. The fermentation of milk with proteolytic starter cultures, such as FAIR E-63 and LA 2, can generate peptidic compounds from milk protein with potential immunostimulating activity. These samples tested in cell culture inhibited lymphocyte proliferation because they showed an acidic pH of 4.5. However, this bioassay was enough sensitive to detect biological activity of different compounds also at low concentrations

Anti-listeria effect of water-soluble extracts of Asiago cheese

Cheese ripening involves a complex series of biochemical events that leads to the characteristics taste, aroma and texture of each cheese variety. The most complex of these biochemical events, proteolysis, is caused by milk, milk-clotting, starter and secondary flora enzymes. During cheese ripening, peptides generation mainly results from caseinolysis. Some of these peptides are bioactive: they exert biological activities such as immunomodulatory, antithrombotic and antibacterial activities. Asiago is a \u201cProtected Denomination of Origin\u201d (PDO) cheese of the North-Eastern region of Italy produced in two different varieties according to the length of ripening. Asiago d\u2019Allevo is the variety produced with skimmed raw milk and ripened for periods varying from 6 to 18 months. The main goal of this research was to evaluate the presence of antibacterial peptides in Asiago d\u2019Allevo cheese toward two bacterial strains. The samples analysed were produced in alpine farms of Asiago plateau (Vicenza, Italy). The presence of antimicrobial peptides was assessed in water-soluble extracts (WSE) of Asiago cheese ultrafiltrated onto 10 kDa cut-off membranes to remove proteins and dialysed in 100 Da cutoff dialysis bags to remove salt and organic acids. The antimicrobial activity of these WSEs was tested on Listeria innocua first. The samples that presented an inhibition were subsequently tested on Listeria monocytogenes. Antimicrobial activity was assayed by a micro-method using 96-well microplates and a microplate reader to determine microbial growth inhibition

TEST in vitro per valutare l'attivit\ue0\ua0 antiossidante e antimicrobica di un estratto vegetale.

The results of two tests in vitro to evaluate antioxidant and antimicrobial activity of grape marc extract are presented. Bovine lymphocytes are incubated for 24 hours in presence of various extract concentrations (5 to 10.5 mg/mL) and subsequently stressed by addition of 15 μM (CuOH) hydroperoxide cumene solution. The intracellular production of ROS (reactive oxygen substances) are detected by partially modified method of DCF-DA (2,7 dichlorofluorescein diacetate), proposed by Rosenkranz et al. (1992). The antimicrobial activity test is carried out on agar plate inoculated by Bacillus stearothermophilus var. calidolactis C 953 spore. The appearance of a halo of inhibition after 24 hours of incubation confirmed the extract antimicrobial activity

152 Insights into the pathogenesis of HHV8-driven body cavity-based lymphoma

Human herpesvirus 8 is associated with the development of primary effusion lymphoma (PEL), an aggressive non-Hodgkin’s lymphoma characterized by the proliferation of the malignant lymphocytes almost exclusively in large serous cavities. The mechanisms involved in the preferential tropism for serous cavities and in the aggressive course of PEL remain to be fully clarified. To study the role of host microenvironment in PEL progression, we previously compared the antineoplastic activity of a murine interferon◊-expressing lentiviral vector (mIFN-◊-LV) to that of a human IFN-◊-LV in a murine model of peritoneal PEL. We demonstrated that in vivo targeting of the murine microenvironment showed an antineoplastic activity comparable to that observed with the hIFN-◊-LV. These findings highlighted the relevant role of body cavity environment in PEL growth and indicated that modulation of microenvironment may impair PEL growth in vivo. By using cocultures of PEL cell lines with human mesothelial cells (HMC), we mimicked the interactions existing in body cavities to analyze the mechanisms involved in PEL progression. PEL cells induced a myofibroblastic morphology in HMC, paralleled by an expression profile indicative of the occurrence of epithelial-mesenchymal transition (EMT). Moreover, HMC increased proliferation and resistance to apoptosis of PEL cells. These data indicate that PEL cells induce EMT in HMC and fibrosis of serous membranes. In turn, HMC modulate PEL cell turnover, thus providing a milieu favorable to PEL progression. These findings open new perspectives into the mechanisms involved in PEL progression and may indicate new targets for PEL treatment

Preliminary investigation on the presence of peptidesinhibiting the growth of Listeria innocua and Listeriamonocytogenes in Asiago d\u2019Allevo cheese

Bacteriocins produced by some strains of lactic acid bacteria or antimicrobial casein fragments can be released into the water-soluble fraction of cheeses during ripening. However, there is a lack of experimental evidence which supports the theory that these peptides can exert an effective antimicrobial effect. The aim of this study was to investigate the anti-listerial activity of such peptides in Asiago d\u2019Allevo cheese. The water-soluble fraction of Asiago was ultrafiltrated through 10 kDa cutoff membranes before being dialyzed (100\u2013500 Da cut-off) to remove proteins, salts, and organic acids, prior to freeze-drying. The growth of Listeria innocua LRGIA 01 and of Listeria monocytogenes strain 162 in Brain Heart Infusion (BHI) at 30 \ub0C in the presence or absence of 5 to 40 mg c5mL 121 of cheese water-soluble extracts (WSEs) lyophilisate was monitored spectrophotometrically. WSEs lyophilisates from cheeses of different production systems (total mixed-ration-fed cows and cheese-making in a dairy plant in May; alpine-grazing cows and cheese-making in situ in July and September) and ripened for 6, 12, and 18 months were tested. A limited dosedependent inhibition of growth was observed at all the assayed concentrations. The addition of cheese WSEs lyophilisates to BHI broth inhibited the growth of <50% of L. innocua LRGIA 01 and <10% of L. monocytogenes strain 162. Antilisterial activity was only significantly affected by ripening time (it was maximal at 6 months). Quantification of peptides with a sequence similar to the antimicrobial casein fragments \u3b1S1-CN f(1\u201323) (isracidin) and \u3b1S2-CN f(183\u2013207) in cheese WSEs suggests that their anti-listerial activity is likely also to be due to other peptides