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1.
This report investigates the requirement for CO 2 for colony formation by Bifidobacterium species in both anoxic and oxic environments. All tested Bifidobacterium species exhibited difficulty in developing colonies in an atmosphere of 100% N 2 but developed well when 1% CO 2 was present. In the presence of CO 2, the oxygen tolerance of the tested species was not improved. In the absence of CO 2, only B. boum, a microaerophilic species, could develop colonies under an N 2-based 5% O 2 atmosphere, indicating that while CO 2 is not an essential factor for colony development, both CO 2 and O 2 have stimulatory effects on B. boum colony development. 相似文献
2.
The sensitivity of photosynthesis to O 2 and CO 2 was measured in leaves from field grown plants of six species ( Phaseolus vulgaris, Capsicum annuum, Lycopersicon esculentum, Scrophularia desertorum, Cardaria draba, and Populus fremontii) from 5°C to 35°C using gas-exchange techniques. In all species but Phaseolus, photosynthesis was insensitive to O 2 in normal air below a species dependent temperature. CO 2 insensitivity occurred under the same conditions that resulted in O 2 insensitivity. A complete loss of O 2 sensitivity occurred up to 22°C in Lycopersicon but only up to 6°C in Scrophularia. In Lycopersicon and Populus, O 2 and CO 2 insensitivity occurred under conditions regularly encountered during the cooler portions of the day. Because O 2 insensitivity is an indicator of feedback limited photosynthesis, these results indicate that feedback limitations can play a role in determining the diurnal carbon gain in the field. At higher partial pressures of CO 2 the temperature at which O 2 insensitivity occurred was higher, indicating that feedback limitations in the field will become more important as the CO 2 concentration in the atmosphere increases. 相似文献
3.
Freshly harvested high-moisture corn with 29.4% moisture and corn remoistened to 19.6% moisture were inoculated with Aspergillus flavus Link ex Fr. and stored for 4 weeks at about 27 C in air (0.03% CO 2, 21% O 2, and 78% N 2) and three modified atmospheres: (i) 99.7% N 2 and 0.3% O 2; (ii) 61.7% CO 2, 8.7% O 2, and 29.6% N 2; and (iii) 13.5% CO 2, 0.5% O 2, and 84.8% N 2. Kernel infections by A. flavus, Fusarium moniliforme (Sheld.) Snyd. et Hans., and other fungi were monitored weekly. The modified-atmosphere treatments delayed deterioration by A. flavus and F. moniliforme, but their growth was not completely stopped. A. flavus survived better in the remoistened than in the freshly harvested corn. F. moniliforme survived in both. A. flavus and F. moniliforme were the dominant fungi in corn removed from the modified atmospheres and exposed to normal air for 1 week. 相似文献
4.
Barley and pea plants were grown under several regimens of different compositions of soil atmosphere, the O 2 concentration varying from 0 to 21% and the CO 2 concentration from 0 to 8%. In absence of CO 2, the effect of O 2 on root length in barley was characterized by equal root lengths within the range of 21 to 7% O 2 and a steep decline between 7 and 0%. In peas, while showing the same general response, the decline occurred between 14 and 7% O 2. Root numbers of the seminal roots of barley decreased already with reduction in O 2 concentration from 21 to 14%. Dry matter production was affected somewhat differently by O 2 and CO 2 concentration. Dry matter production in barley was reduced at 14% O 2 while root length decreased between 7 and 0%. In peas, dry matter production was favored by low CO 2 concentrations except where there was no oxygen. At 21% O 2, increasing CO 2 concentrations did not seem to affect root length up to concentrations of 2% CO 2. At 8% CO 2, root length was decreased. The inter-active effects of CO 2 and O 2 are characterized by a reduced susceptibility to CO 2 at O 2 values below 7%, and a very deleterious effect of 8% CO 2 at 7% O 2. 相似文献
5.
The respiratory requirements of Plasmodium falciparum were studied in vitro in continuous cultivation. The cultures were held in petri dishes containing the parasites incubated in different gas mixtures for periods of 72 to 144 hr with daily media changes. Atmospheres were combinations of 0.5 to 21% O 2 mixed with 1 to 5% CO 2 diluted with N 2. Gas concentrations and the pH of media were measured with an analyzer. Best growth was realized in all cases at 3% O 2 and 1 to 2% CO 2. The culture appeared to be selfperpetuating in O 2 concentrations as low as 0.5% providing the CO 2 was not over 2%. Oxygen concentrations of 21% proved deleterious to growth. The parasite however, failed to grow in the highly reducing atmosphere of anaerobic “Brewer Jars,” suggesting that P. falciparum is an obligate microaerophile. 相似文献
6.
Summary After 10 min illumination of segments of bean ( Phaseolus vulgaris L.) or maize ( Zea mays L.) leaves in air with 14CO 2, the atmosphere was changed to CO 2-free O 2 or N 2 and conversion of photosynthetic products in the light was investigated. The experiments have shown that after the 14CO 2 assimilation period the bean leaves contain the pool of weakly fixed 14C (WF- 14C) which is converted into stable products during the subsequent period of illumination in CO 2-free N 2. In O 2 atmosphere the WF- 14C pool is initially the main source of CO 2 evolved. The marked decrease in radioactivity of sucrose and starch during illumination of bean leaves in O 2 atmosphere indicates that these compounds were also the source of CO 2 evolved in the light. The total amount of previously fixed 14C remained almost on the same level during illumination of maize leaves in N 2 as well as in O 2. However, oxygen changed the distribution of 14C in photosynthetic products, which is suggested to be the consequence of the photorespiration process in maize.Abbreviation WF- 14C
weakly fixed 14C 相似文献
7.
Samples of freshly harvested corn and remoistened corn were inoculated with Aspergillus flavus and stored for 4 weeks at about 27 C in air and three modified atmospheres. Aflatoxins and fat acidity were determined weekly. Corn stored in the modified atmospheres did not accumulate over 15 μg of aflatoxin B 1 per kg and 20 μg of total aflatoxins per kg. Corn from the high CO 2 treatment (61.7% CO 2, 8.7% O 2, and 29.6% N 2) was visibly molded at 4 weeks and had a higher fat acidity than the other treatments. In the N 2 (99.7% N 2 and 0.3% O 2) and controlled atmosphere (13.5% CO 2, 0.5% O 2, 84.8% N 2) treatments, a fermentation-like odor was detected. When the corn was removed from the modified atmospheres it deteriorated rapidly and was soon contaminated with aflatoxins. 相似文献
8.
Summary The assimilation of CO 2 was enhanced in seven plant species by 44% at 30° in the absence of oxygen, and in three of the species by 85% at 40°. Net assimilation of CO 2 was not significantly greater in the absence of O 2 than it was in air with leaves of three tropical grasses and of one dicotyledonous species, Amaranthus palmeri. For two species in 30°, the enhanced CO 2 assimilation values were similar to those of the tropical grasses and of A. palmeri. The absence of O 2 did not enhance net CO 2 assimilation in maize even in light of low intensity. 相似文献
9.
Photosynthetic CO 2 and O 2 exchange was studied in two moss species, Hypnum cupressiforme Hedw. and Dicranum scoparium Hedw. Most experiments were made during steady state of photosynthesis, using 18O 2 to trace O 2 uptake. In standard experimental conditions (photoperiod 12 h, 135 micromoles photons per square meter per second, 18°C, 330 microliters per liter CO 2, 21% O 2) the net photosynthetic rate was around 40 micromoles CO 2 per gram dry weight per hour in H. cupressiforme and 50 micromoles CO 2 per gram dry weight per hour in D. scoparium. The CO 2 compensation point lay between 45 and 55 microliters per liter CO 2 and the enhancement of net photosynthesis by 3% O 2versus 21% O 2 was 40 to 45%. The ratio of O 2 uptake to net photosynthesis was 0.8 to 0.9 irrespective of the light intensity. The response of net photosynthesis to CO 2 showed a high apparent Km (CO 2) even in nonsaturating light. On the other hand, O 2 uptake in standard conditions was not far from saturation. It could be enhanced by only 25% by increasing the O 2 concentration (saturating level as low as 30% O 2), and by 65% by decreasing the CO 2 concentration to the compensation point. Although O 2 is a competitive inhibitor of CO 2 uptake it could not replace CO 2 completely as an electron acceptor, and electron flow, expressed as gross O 2 production, was inhibited by both high O 2 and low CO 2 levels. At high CO 2, O 2 uptake was 70% lower than the maximum at the CO 2 compensation point. The remaining activity (30%) can be attributed to dark respiration and the Mehler reaction. 相似文献
10.
With the ability to symbiotically fix atmospheric N 2, legumes may lack the N-limitations thought to constrain plant response to elevated concentrations of atmospheric CO 2. The growth and photosynthetic responses of two perennial grassland species were compared to test the hypotheses that (1) the CO 2 response of wild species is limited at low N availability, (2) legumes respond to a greater extent than non-fixing forbs to elevated CO 2, and (3) elevated CO 2 stimulates symbiotic N 2 fixation, resulting in an increased amount of N derived from the atmosphere. This study investigated the effects of atmospheric CO 2 concentration (365 and 700 mol mol –1) and N addition on whole plant growth and C and N acquisition in an N 2-fixing legume ( Lupinus perennis) and a non-fixing forb ( Achillea millefolium) in controlled-chamber environments. To evaluate the effects of a wide range of N availability on the CO 2 response, we incorporated six levels of soil N addition starting with native field soil inherently low in N (field soil + 0, 4, 8, 12, 16, or 20 g N m –2 yr –1). Whole plant growth, leaf net photosynthetic rates ( A), and the proportion of N derived from N 2 fixation were determined in plants grown from seed over one growing season. Both species increased growth with CO 2enrichment, but this response was mediated by N supply only for the non-fixer, Achillea. Its response depended on mineral N supply as growth enhancements under elevated CO 2 increased from 0% in low N soil to +25% at the higher levels of N addition. In contrast, Lupinus plants had 80% greater biomass under elevated CO 2 regardless of N treatment. Although partial photosynthetic acclimation to CO 2 enrichment occurred, both species maintained comparably higher A in elevated compared to ambient CO 2 (+38%). N addition facilitated increased A in Achillea, however, in neither species did additional N availability affect the acclimation response of A to CO 2. Elevated CO 2 increased plant total N yield by 57% in Lupinus but had no effect on Achillea. The increased N in Lupinus came from symbiotic N 2 fixation, which resulted in a 47% greater proportion of N derived from fixation relative to other sources of N. These results suggest that compared to non-fixing forbs, N 2-fixers exhibit positive photosynthetic and growth responses to increased atmospheric CO 2 that are independent of soil N supply. The enhanced amount of N derived from N 2 fixation under elevated CO 2 presumably helps meet the increased N demand in N 2-fixing species. This response may lead to modified roles of N 2-fixers and N 2-fixer/non-fixer species interactions in grassland communities, especially those that are inherently N-poor, under projected rising atmospheric CO 2. 相似文献
11.
Reduced photorespiration has been reported in Panicum milioides on the basis of lower CO 2 compensation concentrations than in C 3 species, lower CO 2 evolution in the light, and less response of apparent photosynthesis to O 2 concentration. The lower response to O 2 in P. milioides could be due to reduced O 2 competition with CO 2 for reaction with ribulose 1,5-bisphosphate, to a reduced loss of CO 2, or to an initial fixation of CO 2 by phosphoenolpyruvate carboxylase. Experiments were carried out with Panicum maximum Jacq., a C 4 species having no apparent photorespiration; tall fescue ( Festuca arundinacea Schreb.), a C 3 species; P. milioides Nees ex Trin.; and Panicum schenckii Hack. The latter two species are closely related and have low photorespiration rates. CO 2 exchange was measured at five CO 2 concentrations ranging from 0 to 260 microliters per liter at both 2 and 21% O 2. Mesophyll conductance or carboxylation efficiency was estimated by plotting substomatal CO 2 concentrations against apparent photosynthesis. In the C 4 species P. maximum, mesophyll conductance was 0.96 centimeters per second and was unaffected by O 2 concentration. At 21% O 2 mesophyll conductance of tall fescue was decreased 32% below the value at 2% O 2. Decreases in mesophyll conductance at 21% O 2 for P. milioides and P. schenckii were similar to that for tall fescue. On the other hand, loss of CO 2 in CO 2-free air, estimated by extrapolating the CO 2 response curve to zero CO 2, was increased from 1.8 to 6.5 milligrams per square decimeter per hour in tall fescue as O 2 was raised from 2-21%. Loss of CO 2 was less than 1 milligram per square decimeter per hour for P. milioides and P. schenckii and was unaffected by O 2. The results suggest that the reduced O 2 response in P. milioides and P. schenckii is due to a lower loss of CO 2 in the light rather than less inhibition of carboxylation by O 2, since the decrease in carboxylation efficiency at 21% O 2 was similar for P. milioides, P. schenckii, and tall fescue. The inhibition of apparent photosynthesis by 21% O 2 in these three species at low light intensities was similar at 31 to 36% which also indicates similar O 2 effects on carboxylation. Apparent photosynthesis at high light intensity was inhibited less by 21% O 2 in P. milioides (16.8%) and P. schenckii (23.8%) than in tall fescue (28.4%). This lower inhibition in the Panicum species may have been due to a higher degree of recycling of photorespired CO 2 in these species than in tall fescue. 相似文献
12.
Background and aims Elevated atmospheric CO 2 ( eCO 2) and tropospheric O 3 ( eO 3) can alter soil microbial processes, including those underlying N 2O emissions, as an indirect result of changes in plant inputs. In this study, effects of eCO 2 and eO 3 on sources of N 2O in a soybean ( Glycine max (L.) Merr.) agroecosystem in Illinois (SoyFACE) were investigated. We hypothesized that increases in available C and anaerobic microhabitat under eCO 2 would stimulate N 2O emissions, with a proportionally larger increase in denitrification derived N 2O (N 2O D) compared to nitrification plus nitrifier denitrification derived N 2O (N 2O N+ND). We expected opposite effects under eO 3. Methods Isotopically labeled 15NH 4 14 NO 3 and 14NH 4 15 NO 3 were used to evaluate mineral N transformations, N 2O D, and N 2O N+ND in a 12-day incubation experiment. Results We observed minimal effects of eCO 2 and eO 3 on N 2O emissions, movement of 15?N through mineral N pools, soil moisture content and C availability. Possibly, altered C and N inputs by eCO 2 and eO 3 were small relative to the high soil organic C content and N-inputs via biological N 2-fixation, minimizing potential effects of eCO 2 and eO 3 on N-cycling. Conclusion We conclude that eCO 2 and eO 3 did not affect N 2O emissions in the short term. However, it remains to be tested whether N 2O emissions in SoyFACE will be unaltered by eCO 2 and eO 3 on a larger temporal scale under field conditions. 相似文献
13.
Leaves of Flaveria brownii exhibited slightly higher amounts of oxygen inhibition of photosynthesis than the C 4 species, Flaveria trinervia, but considerably less than the C 3 species, Flaveria cronquistii. The photosynthetic responses to intercellular CO 2, light and leaf temperature were much more C 4-like than C 3-like, although 21% oxygen inhibited the photosynthetic rate, depending on conditions, up to 17% of the photosynthesis rate observed in 2% O 2. The quantum yield for CO 2 uptake in F. brownii was slightly higher than that for the C 4 species F. trinervia in 2% O 2, but not significantly different in 21% O 2. The quantum yield was inhibited 10% in the presence of 21% O 2 in F. brownii, yet no significant inhibition was observed in F. trinervia. An inhibition of 27% was observed for the quantum yield of F. cronquistii in the presence of 21% O 2. The photosynthetic response to very low intercellular CO 2 partial pressures exhibited a unique pattern in F. brownii, with a break in the linear slope observed at intercellular CO 2 partial pressure values between 15 and 20 μbar when analyzed in 21% O 2. No significant break was observed when analyzed in 2% O 2. When taken collectively, the gas-exchange results reported here are consistent with previous biochemical studies that report incomplete intercellular compartmentation of the C 3 and C 4 enzymes in this species, and suggest that F. brownii is an advanced, C 4-like C 3-C 4 intermediate. 相似文献
14.
The quantum yield of photosynthetic electron transport (ΦPSII), evaluated by means of chlorophyll (Chl) fluorescence analysis, has proven to be a useful screening test for drought tolerance in durum wheat ( Triticum durum Desf.). To explore the potential of this parameter further in detecting drought-tolerant genotypes, three cereal species were studied; ΦPSII measurements were carried out under two different gas mixtures, at three points of the induction curve (to obtain the maximal ΦPSII and both the transient and steady-state actual ΦPSII), and at three different water stress levels (moderate, severe and drastic). The species investigated were durum and bread wheat ( Triticum aestivum L.) and barley ( Hordeum vulgare L.); two cultivars per species, characterized by different levels of drought tolerance, were tested. The two gas mixtures used were normal air (21% O 2, 0.035% CO 2 in N 2) to monitor the whole photosynthetic process under physiological conditions, and CO 2 enriched-low O 2 air (1% O 2, 5% CO 2 in N 2) to monitor ΦPSII reduction under stress mainly related to Calvin cycle activity. When ΦPSII related to both assimilatory and non-assimilatory metabolism was evaluated, the cultivar differences observed under normal Air were more representative of the agronomic performance upon drought stress than under high CO 2-low O 2 air. Maximal ΦPSII showed no difference among either cultivars, gas mixtures or stress levels, the efficiency of excitation capture being highly resistant to drought. The ΦPSII evaluated during the transient yielded predictable values in respect of drought tolerance for durum wheat and barley cultivars, highlighting the key role of regulatory processes such as the Mehler peroxidase reaction and possibly also cyclic electron transport, in preventing overreduction under stress. The results clearly show that when Chl fluorescence analysis is used as a parameter in plant breeding, different experimental conditions should be used depending on the physiological mechanism that is bred or selected for. 相似文献
15.
The effect of 21% O 2 and 3% O 2 on the CO 2 exchange of detached wheat leaves was measured in a closed system with an infrared carbon dioxide analyzer. Temperature was varied between 2° and 43°, CO 2 concentration between 0.000% and 0.050% and light intensity between 40 ft-c and 1000 ft-c. In most conditions, the apparent rate of photosynthesis was inhibited in 21% O 2 compared to 3% O 2. The degree of inhibition increased with increasing temperature and decreasing CO 2 concentration. Light intensity did not alter the effect of O 2 except at light intensities or CO 2 concentrations near the compensation point. At high CO 2 concentrations and low temperature, O 2 inhibition of apparent photosynthesis was absent. At 3% O 2, wheat resembled tropical grasses in possessing a high rate of photosynthesis, a temperature optimum for photosynthesis above 30°, and a CO 2 compensation point of less than 0.0005% CO 2. The effect of O 2 on apparent photosynthesis could be ascribed to a combination of stimulation of CO 2 production during photosynthesis, and inhibition of photosynthesis itself. 相似文献
16.
Gluconacetobacter diazotrophicus is an N 2-fixing endophyte isolated from sugarcane. G. diazotrophicus was grown on solid medium at atmospheric partial O 2 pressures (pO 2) of 10, 20, and 30 kPa for 5 to 6 days. Using a flowthrough gas exchange system, nitrogenase activity and respiration rate were then measured at a range of atmospheric pO 2 (5 to 60 kPa). Nitrogenase activity was measured by H 2 evolution in N 2-O 2 and in Ar-O 2, and respiration rate was measured by CO 2 evolution in N 2-O 2. To validate the use of H 2 production as an assay for nitrogenase activity, a non-N 2-fixing (Nif −) mutant of G. diazotrophicus was tested and found to have a low rate of uptake hydrogenase (Hup +) activity (0.016± 0.009 μmol of H 2 10 10 cells −1 h −1) when incubated in an atmosphere enriched in H 2. However, Hup + activity was not detectable under the normal assay conditions used in our experiments. G. diazotrophicus fixed nitrogen at all atmospheric pO 2 tested. However, when the assay atmospheric pO 2 was below the level at which the colonies had been grown, nitrogenase activity was decreased. Optimal atmospheric pO 2 for nitrogenase activity was 0 to 20 kPa above the pO 2 at which the bacteria had been grown. As atmospheric pO 2 was increased in 10-kPa steps to the highest levels (40 to 60 kPa), nitrogenase activity decreased in a stepwise manner. Despite the decrease in nitrogenase activity as atmospheric pO 2 was increased, respiration rate increased marginally. A large single-step increase in atmospheric pO 2 from 20 to 60 kPa caused a rapid 84% decrease in nitrogenase activity. However, upon returning to 20 kPa of O 2, 80% of nitrogenase activity was recovered within 10 min, indicating a “switch-off/switch-on” O 2 protection mechanism of nitrogenase activity. Our study demonstrates that colonies of G. diazotrophicus can fix N 2 at a wide range of atmospheric pO 2 and can adapt to maintain nitrogenase activity in response to both long-term and short-term changes in atmospheric pO 2. 相似文献
17.
The aim of the present study was to evaluate the effects of forced ventilation and CO 2 enrichment (360 or 720 μmol mol ?1 CO 2) on the in vitro growth and development of Pfaffia glomerata, an endangered medicinal species, under photomixotrophic or photoautotrophic conditions. P. glomerata nodal segments showed substantial differences in growth, relative water content and water loss from leaves, photosynthetic pigments, stomatal density, and leaf anatomical characteristics under these different treatments. CO 2 enrichment led to increased photosynthetic pigments and reduced stomatal density of in vitro cultivated P. glomerata. A lack of sucrose in the culture medium increased 20-hydroxyecdysone levels, but the increase in CO 2 levels did not further elevate the accumulation of 20-hydroxyecdysone. All growth increased in a CO 2-enriched atmosphere. In addition, CO 2 enrichment, with or without sucrose, gave a lower relative water loss from leaves. This finding indicates that either a photoautotrophic or photomixotrophic system in a CO 2-enriched atmosphere may be suitable for large-scale propagation of this species. 相似文献
18.
Light-dependent O 2 exchange was measured in intact, isolated soybean ( Glycine max. var. Williams) cells using isotopically labeled O 2 and a mass spectrometer. The dependence of O 2 exchange on O 2 and CO 2 was investigated at high light in coupled and uncoupled cells. With coupled cells at high O 2, O 2 evolution followed similar kinetics at high and low CO 2. Steady-state rates of O 2 uptake were insignificant at high CO 2, but progressively increased with decreasing CO 2. At low CO 2, steady-state rates of O 2 uptake were 50% to 70% of the maximum CO 2-supported rates of O 2 evolution. These high rates of O 2 uptake exceeded the maximum rate of O 2 reduction determined in uncoupled cells, suggesting the occurrence of another light-induced O 2-uptake process ( i.e. photorespiration). Rates of O2 exchange in uncoupled cells were half-saturated at 7% to 8% O2. Initial rates (during induction) of O2 exchange in uninhibited cells were also half-saturated at 7% to 8% O2. In contrast, steady-state rates of O2 evolution and O2 uptake (at low CO2) were half-saturated at 18% to 20% O2. O2 uptake was significantly suppressed in the presence of nitrate, suggesting that nitrate and/or nitrite can compete with O2 for photoreductant. These results suggest that two mechanisms (O2 reduction and photorespiration) are responsible for the light-dependent O2 uptake observed in uninhibited cells under CO2-limiting conditions. The relative contribution of each process to the rate of O2 uptake appears to be dependent on the O2 level. At high O2 concentrations (≥40%), photorespiration is the major O2-consuming process. At lower (ambient) O2 concentrations (≤20%), O2 reduction accounts for a significant portion of the total light-dependent O2 uptake. 相似文献
19.
The photosynthetic CO 2 fixation by spinach leaf ( Spinacia oleracea L. var. Kyoho) protoplasts was inhibited by substituting an atmosphere of N 2 with one of either air (21% O 2) or 100% O 2. The inhibitory effect of 100% O 2 was greater than that of air. The mode of inhibition by 100% O 2 and air was competitive with respect to CO 2; Ki(O 2) value was 0.32 mM at pH 7 and 0.28 mM at pH 8.5 The labeling patterns of compounds in protoplasts exposed to 14CO 2 in light after transferring them from N 2 to O 2 atmospheres were examined. There was no detectable 14CO 2 incorporation into glycolate under anaerobic and O 2 atmospheres; a more marked labeling of glycine occurred under an oxidative environment compared to that under the anaerobic condition, presumably because of a rapid transformation of glycolate to glycine in the protoplasts. 相似文献
20.
The shelf life of Graviera cheese, a full fat cheese produced in Heraklion (Crete Greece), was investigated. Graviera cheese was stored at 4 °C for up to 90 days in polyamide packages under three different modified atmosphere compositions. Control cheeses were packaged in air whereas MAP mixtures were MAP 1: 40% CO 2/55% N 2/5% O 2, MAP 2: 60% CO 2/40% N 2 and MAP 3: 50% CO 2/50% N 2. Sampling of product was carried out every 10 days to investigate its sensory quality and microbiological characteristics. Ten trained panelists participated in the sensory panel to evaluate the cheeses for external appearance (color, texture), taste, and flavor in a scale from 1 to 10 (1 very poor, 10 very good). The microbiological analysis revealed that there were no colonies of Staphylococcus aureus and Listeria monocytogenes whereas both Escherichia coli and Total Viable Counts (TVC) increased strongly in control samples but were inhibited under all MAP compositions. 相似文献
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