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The state of demersal fishery in the Southern Adriatic Sea (GFCM-GSA 18, Central Mediterranean), years 1996–2003, from a biological, social and economic point of view was analysed using 47 indicators: 22 biological indicators obtained from fishery-independent data through yearly experimental bottom trawl surveys (“Medits” Programme), and 25 socio-economic indicators estimated from fishery-dependent data, available from the monitoring system of the Italian Institute for Economic Research on Fisheries and Aquaculture (IREPA). Biological indicators were applied for “single-species” (Eledone cirrhosa, E. moschata, Illex coindetti, Merluccius merluccius, Mullus barbatus, Nephrops norvegicus, Parapenaeus longirostris, Raja clavata, Zeus faber) and for “multi-species” analysis. Economic indicators describing economic performance, productivity, costs and prices, and the overall economic sustainability of fishery were estimated. Social indicators and a general indicator summarising social sustainability were also considered. Indicators’ values were displayed using the Traffic Light system. Both fishery-independent and fishery-dependent indicators highlighted a progressive decline of the trawl fishery system in the GSA 18. This decline was mainly related to the ongoing depletion of the traditional fishery target species (mostly long-living, late-maturing species) partially replaced by the increase of traditional accessory species (generally short-living species), as well as to the reduction of productivity and increasing costs. The whole procedure was proposed as a contribution to the identification and applicability of bio-economic indicators for fishery management purposes.  相似文献   
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The aim of this work was to verify the potential of infrared (IR) spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation (MLF) occurring in a model-wine and the further cells autolysis. MLF in wine is a secondary biotransformation due to lactic acid bacteria that usually occurs spontaneou,;ly or after starter inoculation at the end of alcoholic fermentation. Nowadays, it is desirable to supply winemakers with a new rapid and non-destructive approach to monitor MLF progress and 1R spectroscopy technology appears to be suitable for this purpose. The transformation of L-malic acid into L-lactic acid was carried out by inoculating a synthetic wine with an Oenococcus oeni culture and it was monitored through microbiological and chemical methods. At the same time, Fourier transform near infrared (FT-NIR) spectral data, in diffusive transflection mode using an optic probe, and FT-IR spectra, using an germanium crystal attenuated total reflectance (ATR) cell, were collected. Principal component analysis of the spectra was able to identify absorption bands related to the key molecular modifications that took place during the L-malic acid transformation. Thus, the samples were discriminated according to the fermentation phase. Although this study is a preliminary approach, results confirm that near infrared (NIR) and mid infrared (MIR) spectroscopy could be successfully applied to detect the start of MLF and the autolysis of the lactic acid bacteria (LAB) cells.  相似文献   
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The aims of this work were to evaluate the effects of different concentrations of hexanal, (E)-2-hexenal, hexyl acetate, and their mixtures on the fate of pathogenic species such as Escherichia coli, Salmonella enteritidis, and Listeria monocytogenes inoculated in model systems as well as the antimicrobial activity against the target species of the chosen molecules when added to the packaging atmosphere of inoculated fresh-sliced apples. The result obtained in this work pointed out the potential use of compounds such as hexanal, (E)-2-hexenal, and hexyl acetate for both the extension of shelf life and an improvement of hygienic safety of "minimally processed foods". In fact, hexanal, (E)-2-hexenal, and hexyl acetate had a significant inhibitory effect against pathogen microorganisms frequently isolated from raw materials (E. coli, S. enteritidis, and L. monocytogenes) when inoculated in both model and real systems. In this last condition, these compounds, at the levels used (150, 150, and 20 ppm for hexanal, hexyl acetate, and (E)-2-hexenal, respectively), displayed a bactericide effect on L. monocytogenes and they exhibited significant extensions of lag phase of E. coli and S. enteritidis inoculated at levels of 10(4)-10(5) CFU/g.  相似文献   
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Polygonum tinctorium Ait. is a herbaceous subtropical annual plant, belonging to the family Polygonaceae. Within the cells of its leaves P. tinctorium accumulates large amounts of a colorless glycoside, indican (indoxyl beta-d-glucoside), from which the blue dye indigo is synthesized. P. tinctorium is well-known in Japan, where it had been cultivated to produce natural indigo for textile dyeing, whereas it represents a potentially interesting new crop in Europe. To better understand the effects of environmental parameters on P. tinctorium crop production and indigo yield, field experiments were carried out in central Italy under temperate climate. Three lines were tested during the 2001 and 2002 growing seasons, and plant/leaf yields as well as indican contents were evaluated. The results showed that P. tinctorium grown in temperate climate conditions can be harvested three times a year. Yields of 82 and 120 t ha(-1) of fresh plant yield were obtained in 2001 and 2002, respectively. The contrasting weather conditions between the two years significantly affected biomass production, which was higher in the 2002 season, characterized by wet weather conditions. The cycle length from sowing to the last harvest was accomplished in 229-238 days when plants had accumulated 2017-2018 degrees C. Green leaves accounted for 40-45% by weight of fresh plant tissue and contained 11-20 g kg(-1) indican. The three lines did not significantly differ in the main productive parameters or in fresh leaf indican content (14.1 g kg(-1) mean value). Photosynthetic active radiation influences indican leaf production according to the model y = 0.0004x + 8.566 (P < 0.01, correlation coefficient = 0.818). Indican content ranged from 12 to 25 g kg(-1) of fresh leaves with PAR daily values from 10000 to 40000 mEinstein m(-2) (recorded in May and at the end of July-beginning of August, respectively). The results indicate that in nonlimiting rainfall conditions a very high indican content and a potentially high indigo yield can be obtained by cultivating P. tinctorium in this pioneer geographical area.  相似文献   
6.
The aim of this research was to assess the antimicrobial activity of nine different industrial essences used in a soft drink factory in relation to their composition, as well as to verify the role of vapor pressure on their bioactivity. The essences were tested against a Saccharomyces cerevisiae strain isolated from spoiled soft drinks. The tests were carried out by adding the essences directly to a liquid medium or into the headspace of closed systems inoculated with the yeast. The headspace composition was evaluated through a solid phase microextraction-gas chromatography technique. The use of a mass spectrometer allowed the identification of the peaks detected. The microbial growth was indirectly monitored by measuring the metabolic CO2 released by the yeast. The results obtained indicated that the most effective essences were characterized by the highest concentration of some terpenes, such as citral, beta-pinene, and p-cymene. Moreover, all of the essences were more bioactive when added directly to the liquid medium.  相似文献   
7.
Gluten-free (GF) products are consumed both by individuals with celiac disease and by an increasing number of people with no specific medical needs. Although the technological quality of GF products has been recently improved, their nutritional quality is still scarcely addressed. Moreover, the few published studies report conflicting results, mostly because the information from product nutrition facts is the only considered factor. The aim of the present study was to develop a score-based method for the nutritional evaluation of 134 packaged Italian GF bakery products and to compare it with that of 162 matched gluten-containing (GC) food items. The score included the information from the nutrition facts and the presence/absence of some nutritionally relevant components in the ingredients list. Results indicated an overall low nutritional quality of the considered GF bakery products. Additionally, with the sole exception of GF bread substitutes, there was no difference in nutritional quality between GF and equivalent GC bakery products. Future research and development of GF bakery products may take advantage of this scoring method, as it may represent an easy approach to evaluate their nutritional quality. The present findings do not justify the consumption of packaged GF bakery products by people without any specific medical needs.  相似文献   
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Antioxidant activity (AA) of durum wheat (Triticum durum Desf.) grains was studied using the innovative LOX/RNO method, able to simultaneously detect different antioxidant mechanisms, and the TEAC assay, one of the most widely used assays. Insoluble-bound and free-soluble phenols, hydrophilic and lipophilic compounds were extracted from eight different whole flour samples; extracts were analyzed for AA and their content in several antioxidants. The LOX/RNO method measured very high AA values, with the highest ones [850–1500 μmol Trolox eq./g whole flour (dry weight)] for insoluble-bound phenolic extracts, highly correlated to total phenolic (r = 0.761, P < 0.001) and ferulic acid (r = 0.816, P < 0.001) contents. Hydrophilic and lipophilic extracts showed lower AA [70-140 and 40–60 μmol Trolox eq./g (dry weight), respectively], highly correlated to flavonoid (r = 0.583, P < 0.01) and protein (r = 0.602, P < 0.01), as well as β-tocotrienol (r = 0.684, P < 0.05) contents, respectively. Interestingly, the LOX/RNO method suggests that insoluble-bound phenolic compounds may exert very strong synergistic interactions within the extract. Contrarily, the TEAC assay did not correlate to any antioxidant content, resulted unable to highlight differences among samples, measured much lower AA values and did not suggest synergism. The use of the LOX/RNO method is useful to unearth new properties of phytochemicals from durum wheat grains, potentially giving health benefits.  相似文献   
10.
A phytoplasma-associated disease was identified in Brassica campestris (sarson) plants during a survey conducted in Punjab province of Pakistan in 2014–2016. The symptomatic plants showed characteristic symptoms of phyllody and witches’ broom. Phytoplasma presence was detected by polymerase chain reaction on 16S ribosomal and tuf DNAs, followed by RFLP analysis and sequence comparison of the 16S rRNA and tuf genes. The phytoplasma detected was classified in a new ribosomal subgroup designed 16SrIX-H. The phytoplasma presence in phloem tissues of symptomatic sarson samples was also confirmed through light microscopy and transmission studies to healthy plants through dodder and the leafhopper Orosius albicinctus. This is the first report of identification of 16SrIX-H subgroup phytoplasma associated with sarson and its natural vector in Pakistan.  相似文献   
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