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1.
Rhodopseudomonas acidophila KU001 was isolated from leather industry effluents and the effect of different cultural conditions on hydrogen production was studied. Anaerobic light induced more hydrogen production than anaerobic dark conditions. Growing cells produced more amounts of hydrogen between 96 and 144 h of incubation. Resting and growing cells preferred a pH of 6.0 ± 0.24 for hydrogen production. Succinate was the most preferred carbon source for the production of hydrogen while citrate was a poor source of carbon. Acetate and malate were also good carbon sources for hydrogen production under anaerobic light. Among the nitrogen sources, R. acidophila preferred ammonium chloride followed by urea for production of hydrogen . L‐tyrosine was the least preferred nitrogen source by both growing and resting cells. 相似文献
2.
Abstract The interaction between light availability and the biosynthesis of phenolic compounds in fruit of kiwifruit ( Actinidia deliciosa var. deliciosa, C.F. Liang et A. R. Ferguson) was investigated. Fruits were exposed either to natural light or were artificially shaded while growing on mature vines and were analysed weekly during the first 11 weeks of development. Phenols were identified and quantified by using High Performance Liquid Chromatography (HPLC). Results showed that the predominant phenolic compounds were hydroxycinnamic acids (HCAs), flavonols and the flavan 3-ol epicatechin. Calcium (Ca 2+), the main mineral nutrient involved in fruit quality was also determined. Light significantly increased the accumulation of both phenols and Ca 2+ into the fruit. This work expands the list of known phenolics in kiwifruit and provides a possible explanation for the seasonal pattern of Ca 2+ import into the fruit. Results on light–phenol interaction being apparently beneficial for fruit Ca 2+ accumulation, suggest that accurate canopy management could enhance fruit quality. 相似文献
3.
Aims: To increase the fruit body production of Cordyceps guangdongensis, selected cultivation conditions, especially nutritional parameters were optimized. Methods and Results: Cordyceps guangdongensis was inoculated on potato dextrose agar slants with pH values from 4·5 to 9·0 and cultivated in artificial media with different carbon and nitrogen supplements. Primordium formation in C. guangdongensis was favoured by slightly acidic conditions. Fruit body yields and biological efficiency (BE) recorded were all highest in cultures of C. guangdongensis supplemented with sucrose and KNO 3 as carbon and nitrogen supplements, respectively. Highest fruit body yields and BE values were recorded with C : N ratio of 12 : 1. The optimal medium consisted of (g l ?1) 20·0 sucrose, 4·0 soya bean powder, 5·0 beef extract and 10·0 KNO 3. Cultivation experiments using this medium confirmed its reliability; 18·35% of BE was obtained, compared with a calculated maximum BE of 18·65% based on orthogonal test data. Conclusions: Cordyceps guangdongensis preferred sucrose and potassium nitrate as best carbon and nitrogen supplements. It produced satisfying yield of fruit body with optimized medium. Significance and Impact of the Study: Optimized artificial cultivation conditions could promote the yield of C. guangdongensis and decreased the cost of production. 相似文献
4.
Gluconobacter oxydans that produces the cellulose was isolated. In order to confirm the chemical features of cellulose, various spectrophtometeric
analysis were carried out using electron microscopy, X-ray diffractogram, and CP/MAS 13C NMR. The purified cellulose was found to be identical to that of Acetobacter xylinum. For effective production of cellulose, the various carbon and nitrogen sources, mixture of calcium and magnesium ions, and
biotin concentration were investigated in flask cultures. Among the various carbon sources, glucose and sucrose were found
to be best for the production of cellulose, with maximum concentration of 2.41 g/L obtained when a mixture of 10 g/L of each
glucose and sucrose were used. With regard to the nitrogen sources, when 20 g/L of yeast extract was used, the maximum concentration
of bacterial cellulose was reached. The concentration of cellulose was increased with mixture of 2 mM of each Ca 2+ and Mg 2+. The optimum biotin concentration for the production of cellulose was in the range of 15 to 20 mg/L. At higher biotin concentration
(25–35 mg/L), the bacterial cellulose production was lower. 相似文献
5.
Calcium nitrate (20 g litre ?1) delayed persimmon ( Diospyros kaki) ripening on the tree and also reduced postharvest fruit deterioration when applied prior to fruit colour break. The magnitude of the response depended on the date of treatment. Application made one month prior to the peak of estimated commercial harvest was the most efficacious, and colour development, fruit softening and ethylene production were significantly retarded by the treatment. At harvest, there was no effect on fruit size or soluble solids content. Although there was a tendency for the content of soluble solids and fruit firmness to decrease with storage period, firmness of treated fruit was maintained. 相似文献
6.
Proboscis monkey ( Nasalis larvatus) feeding behavior and ecology were studied at the Natai Lengkuas Station, Tanjung Puting National Park, Kalimantan Tengah,
Indonesia. Data on feeding behavior were collected using scan sampling during group follows. Three vegetational plots containing
1,732 trees were established and monitored monthly for changes in fruit, flower, and young leaf production. Basal area and
canopy cover were calculated and used in estimating food abundance. Proboscis monkeys were found to be folivore/frugivores,
specializing in seed consumption. At least 55 different plant species were used as food sources, with a marked preference
for Eugenia sp. 3/4, Ganua motleyana and Lophopetalum javanicum. These tree species were among the most frequent and most dominant. However, proboscis monkeys were selective feeders; use
of tree species as food sources was not based simply on relative density. During times of low food abundance and/or availability
proboscis monkeys switched dietary strategies and increased dietary diversity. The average total home range was estimated
to be 130.3 ha, with an average group density of 5.2 groups per km 2. The average biomass per km 2 was estimated to be 499.5 kg. Given their high biomass and predilection for consuming seeds of dominant species, proboscis
monkeys may help to maintain and increase vegetational diversity. 相似文献
7.
Aims: The objective of this study is to optimize the levels of carbon and nitrogen sources of the medium in shake flask experiments and evaluate the effect of pH and dissolved oxygen (DO) on the production of l ‐asparaginase from a newly isolated Serratia marcescens SK‐07 in a batch bioreactor. Methods and Results: Central composite rotatable design (CCRD) was applied to optimize the levels of carbon and nitrogen sources of the medium in shake flask experiments. The optimal levels of l ‐asparagine, glucose, yeast extract and peptone were found to be 4·93, 3·81, 3·65 and 1·47 g l ?1, respectively, and maximal l ‐asparaginase production of 25·02 U mg ?1 was obtained under these conditions. Among the carbon sources tested, l ‐asparagine was identified to be the most favourable carbon source for enhanced production of l ‐asparaginase. The maximum l ‐asparaginase production of 29·89 U mg ?1 was achieved in a batch bioreactor at initial pH of 6·5 (uncontrolled) and DO level of 40% in the culture. Conclusions: We have isolated, screened and identified the potential micro‐organism, S. marcescens, for the production of l ‐asparaginase. An overall 5·55‐fold increase in the production was achieved under optimal levels of carbon and nitrogen sources, DO level and at initial pH of 6·5 (uncontrolled). Significance and Impact of the Study: The experiments illustrate the importance of statistical method for optimization of carbon and nitrogen sources and study the effect of physical process parameters on the production of l ‐asparaginase in shake flask and bioreactor, respectively. This study would be helpful for bioprocess development of bacterial l ‐asparaginase production. 相似文献
8.
We tested the hypothesis that fruit quantity and quality vary vertically within trees. We quantified intratree fruit production
before exploitation by frugivores at different heights in 89 trees from 17 species fed on by primates in Kibale National Park,
Uganda. We also conducted a pilot study to determine if the nutritional value of fruit varied within tree crowns. Depending
on the species and crown size, we divided tree canopies into 2 or 3 vertical layers. In 2-layered trees, upper crowns produced
fruits that were 9.6–30.1% bigger and 0.52–140 times the densities of those from lower crowns, with one exception. Among 2-layered
trees, upper crowns produced a mean of 46.9 fruits/m 3 (median 12.1), while lower crowns produced a mean of 14.1 fruits/m 3 (median 2.5). Among 3-layered trees, upper crowns produced a mean density of 49.9 fruits/m 3 (median 12.5), middle crowns a mean of 16.8 fruits/m 3 (median 6.6), and lower crowns a mean of 12.8 fruits/m 3 (median 1.8). Dry pulp and moisture were systematically greater per fruit in the highest compared to the lowest canopy layers
(22.4% and 16.4% respectively in 2-layered trees, 49.7% and 21.8% respectively in 3-layered trees). In 1 tree of Diospyros abyssinica, a pilot nutritional study showed that upper crown ripe fruit contained 41.9% more sugar, 8.4% more crude proteins, and 1.8
times less of the potentially toxic saponin than lower crown ripe fruit, but the result needs to be verified with more individuals
and species of trees. We discuss the consequences of intratree variations in fruit production with respect to competition
among frugivorous primates. 相似文献
9.
Asexual fruit body formation of an entomogenous, Paecilomyces tenuipes, on an artificial culture medium was investigated. For the fruit body induction, light/dark condition was important. Illumination
by white light in a particular critical period preceded by a dark period induced the fruit bodies. The critical period was
identified to be around 6–14 d after inoculation at 20°C. 相似文献
10.
Among carbon sources studied, cellobiose and mannitol provided the highest laccase (Lac) activity (648 and 742 U1 -1, respectively) of Trametes versicolor 775 while glucose gave maximum manganese peroxidase (MnP) and peroxidase activities (44 and 114U1 -1, respectively). Citrus fruit peel as growth substrate enhanced Lac activity 7-fold when compared to the medium with cellobiose, whereas grape vine sawdust increased MnP and peroxidase activity up to 148 and 677U1 -1, respectively. 相似文献
11.
AbstractA novel tannase and gallic acid-producing Penicillium rolfsii (CCMB 714) was isolated from cocoa leaves from the South of Bahia. The influence of nutritional sources and the simultaneous effect of parameters involved in the fermentation process were available. Tannase (9.97 U?mL ?1) and gallic acid (9?mg mL ?1) production were obtained in 48?h by submerged fermentation in non-optimized conditions. Among the carbon sources, tested gallic acid and tannic acid showed the highest tannase production ( p<.05) when compared with methyl gallate and glucose. After optimization using the temperature and tannic acid concentration as variables with the Central Compound Rotational Design (CCRD), the maximal tannase production (25.6?U mL ?1) was obtained at 29.8?°C and 12.7%, respectively, which represents an increase of 2.56 times in relation to the initial activity. The parameters optimized for the maximum production of gallic acid (21.51?mg mL ?1) were 30?°C and 10% tannic acid. P. rolfsii CCMB 714 is a new strain with a high tannase and gallic acid production and the gallic acid produced is very important, mainly for its applications in the food and pharmaceutical industry. 相似文献
12.
Glasshouse experiments were conducted to evaluate the influence of L-methionine (L-MET) and L-ethionine (L-ETH) added to soil
on the growth of corn ( Zea mays L.) and tomato ( Lycopersicon esculentum), respectively. The application of L-MET and L-ETH stimulated C 2H 4 production in soil by 299- and 313-fold, respectively, over an unamended control. An L-MET treatment of 1.85 mg kg −1 soil was the most effective in increasing shoot height, shoot fresh weight, internodal distance, and stem diameter in two
corn cultivars, Kandy Korn and Miracle, while shoot and root dry weights, leaf width, uppermost leaf collar base distance
and resistance to stem breaking were increased in the case of Kandy Korn only. A significant epinastic response was observed
in the second and third leaves of tomato plants when soil was treated with L-ETH. An L-ETH treatment of 0.2 mg kg −1 soil resulted in the maximum fresh fruit yield, while 0.02 and 2.0 mg kg −1 gave the most fruit and greater average weight of fresh fruit, respectively. Concentrations ranging from 0.002 to 2.0 mg
L-ETH kg −1 soil initiated early fruit formation. Early fruit ripening was observed with an application rate of 20 mg L-ETH kg −1 soil. The mechanism of action of these chemicals could either be attributed to i) substrate-dependent C 2H 4 production in soil by the indigenous microflora, ii) uptake directly by plant roots followed by metabolism within the tissues,
and/or iii) a change in the balance of rhizosphere microflora affecting plant growth. 相似文献
13.
Light supply is one of the most important factors affecting autotrophic growth of microalgae. This study investigated the effect of the type and light intensity of artificial light sources on the cell growth of an indigenous microalga Chlorella vulgaris ESP‐31 obtained from southern Taiwan. In addition, a dissolved inorganic carbon source ( i.e. sodium bicarbonate) was used to improve the biomass production of strain ESP‐31. The results show that a new fluorescent light source (TL5) was effective in indoor cultivation of microalgae. Better overall productivity of 0.029 g dry cell weight/L‐d was obtained when using TL5 lamps as the light source with a light intensity of 9 W/m 2. A carbon source (sodium bicarbonate) concentration of 1000 mg/L was found to be optimal for the growth of strain ESP‐31 in terms of both biomass production and carbon source utilization. Under the optimal growth conditions, the resulting microalgal biomass consisted of 25–30% protein, 6–10% carbohydrate, and 30–40% lipid. 相似文献
14.
Net primary production (NPP) is an important function of plant communities which has not often been examined seasonally in a forested ecosystem. The major objective of the study was to measure above-ground NPP seasonally and relate it to phenological activity on a hardwood forest watershed at Coweeta Hydrologic Laboratory, North Carolina. NPP was estimated as the increase in biomass, estimated from regression equations on diameter. Diameter increases were measured by vernier tree bands. Phenological observations were made on bud break, leaf emergence, flowering, mature fruit, leaf senescence, and leaf fall. The species studied intensively were Acer rubrum, Quercus prinus, Carya glabra, Cornus florida, and Liriodendron tulipifera. Liriodendron was found to be the most productive species per individual, but Quercus prinus was the most productive per unit ground area. The total watershed estimate of aboveground NPP was 8,754 kg ha -1 yr -1 and included 47.9% leaves, 33.2% wood, 7.8% bark, 4.8% reproductive tissues, 4.2% loss to consumers, and 2.1% twigs. Increases in leaf biomass were most rapid in the spring, but woody tissue production peaked in June and continued through August. Since leaf production peaked in the spring, the plants' photosynthetic machinery was activated early in the growing season to support woody tissue production, which followed the period of rapid leaf growth, and reproductive activity. Flowering occurred during the leaf expansion period except for Acer rubrum, which flowered before leaf emergence. Fruit maturation occurred during late summer to early fall, when there were no additional biomass increases. Acer rubrum was an exception as its fruit matured during the period of leaf expansion. 相似文献
15.
Background Tomato ( Solanum lycopersicum) consumption has been one of the most common causes of produce-associated salmonellosis in the United States. Contamination
may originate from animal waste, insects, soil or water. Current guidelines for fresh tomato production recommend the use
of potable water for applications coming in direct contact with the fruit, but due to high demand, water from other sources
is frequently used. We sought to describe the overall bacterial diversity on the surface of tomato fruit and the effect of
two different water sources (ground and surface water) when used for direct crop applications by generating a 454-pyrosequencing
16S rRNA dataset of these different environments. This study represents the first in depth characterization of bacterial communities
in the tomato fruit surface and the water sources commonly used in commercial vegetable production. 相似文献
16.
Information on the fruit diets of howling monkeys and fruit-eating bats in the tropical rain forest of Los Tuxtlas, Mexico was collected for a year to compare the plant species used. Howling monkeys used 19 plant species whereas bats used 32 plant species as fruit sources. Eleven species were common in the diet of both mammals. A rank analysis at the plant species level showed that the fruit diets of Alouatta and Artibeus were very different. In contrast to bats, howling monkeys displayed a seasonal pattern in fruit consumption. Diet overlap between the two mammals was highest during the monkeys' fruit-eating season. Measures of fruit production in eight trees (four species) indicated marked variations in fruit biomass produced and in length of fruiting from tree to tree and species to species. Peaks in fruit production were typical both at the species and the individual tree levels, demonstrating the very patchy nature of the fruit available to the monkeys and the bats. 相似文献
17.
Phytoplankton productivity in the Canada Basin was measured in the late summer season, from mid-September to mid-October 2009,
using a 13C– 15N dual tracer technique. To understand potential production changes associated with sea ice melting in the Arctic Ocean, we
examined the effects of light enhancement and nitrate enrichment on the carbon productivity of phytoplankton from the chlorophyll
a maximum layer. The daily carbon productivity in the Canada Basin in 2009 was very low, with a mean of 4.1 mg C m −2 (SD = 3.6 mg C m −2), compared with those reported in previous studies in the region. Among several explanations, the most plausible reason for
the large difference in carbon productivity between this and the previous studies was strong seasonal variation in biomass
and photosynthetic rate of the phytoplankton in the study region. Based on our results from light enhancement and nitrate
enrichment experiments, we found that carbon productivity of phytoplankton in the chlorophyll a maximum layer could be stimulated by increased light condition rather than nitrate addition. Thus, potentially increasing
light availability from current and ongoing decreases in the sea ice cover could increase the carbon production of the phytoplankton
in the chlorophyll a maximum layer and produce a well-developed maximum layer at a deeper depth in the Canada Basin. 相似文献
18.
Rhodotorula sp. produced a high yield of levanase (12.5 nkat/mL) in shake flasks in basal medium containing 1% maltose as the sole carbon
source. Among the different carbon sources used, maltose was found to be the best for levanase production. The optimum temperature
and pH for levanase production were 30°C and 6, respectively. In a batch reactor the enzyme productivity was higher (500 nkat
L −1 h −1) than in shaken flasks (347 nkat L −1 h −1). 相似文献
19.
Studies were conducted on agar media to optimise sporulation of Drechslera avenacea, a fungal pathogen being evaluated as a biological control agent for Avena species (wild oats). Conidium production was affected by nutrition, pH, temperature and light conditions. Of the agar media tested, Czapek Dox agar (CZA) and half-strength oatmeal agar (½OMA) were the only media where sporulation occurred at all temperatures tested under a 12-h light:12-h dark photoperiod (L/D). The optimum temperature for conidium production was 20°C on ½OMA, whereas there was no optimum temperature on CZA. Under a 12-h near-ultraviolet (NUV):12-h dark photoperiod (NUV/D), similar numbers of conidia were produced on CZA at 6.66, 14.56, and 22.78 W m ?2, whereas on ½OMA conidium production was the highest at 14.56 W m ?2. When NUV/D and L/D conditions were compared, similar numbers of conidia where produced on CZA, whereas ½OMA conidium production was superior under the NUV/D photoperiod. Considerable variation in sporulation and degree of virulence of D. avenacea was detected among isolates from different geographic areas. The most virulent conidia were obtained on ½OMA at 20°C incubated under continuous illumination NUV light. Therefore, the most suitable conditions for conidium production of D. avenacea were growth for 1 week on ½OMA at 20°C under continuous NUV at an intensity of 14.56 W m ?2. Under these conditions, 1.1×10 5 conidia mL ?1 were produced which is the highest sporulation yet reported for any Drechslera spp., which are traditionally poor sporulators. 相似文献
20.
In wetland ecosystem, nitrogen along with other elements and its management is most imperative for the production of so many aquatic food, non-food and beneficial medicinal plants and for the improvement of soil and water characteristics. With great significant importance of INM (integrated nutrient management) as sources, emphasizing on management on nitrogen as a key element and its divergence, a case study was undertaken on such aquatic food crops (starch and protein-rich, most popular and remunerative) in the farmers’ field of low-lying ‘Tal’ situation of New Alluvial Zone of Indian subtropics. The study was designed in factorial randomized block design, where, three important aquatic food crops (water chestnut (Trapa bispinosa Roxb.), makhana (Euryale ferox Salisb.) and water lily (Nymphaea spp.) as major factor and eleven combinations of organic and inorganic sources of nutrients as sub-factor was considered in the experiment. It revealed from the results that the production of fresh kernels or nuts of water chestnut (8.57 t ha−1), matured nut yield of makhana (3.06t ha−1) and flower stalks of water-lily as vegetables (6.38 t ha−1) including its nutritional quality (starch, protein, sugar and minerals) was remarkably influenced with the application of both organic (neem oilcake @ 0.2 t ha−1) and inorganic sources (NPK @ 30:20:20 kg ha−1 along with spraying of NPK @ 0.5% each over crop canopy at 20 days interval after transplanting) than the other INM combinations applied to the crops. Among the crops, highest WCYE (water chestnut yield equivalence) exhibited in makhana due to its high price of popped-form in the country, which is being exported to other countries at now. Sole application of both (organic and inorganic sources) with lower range did not produce any significant outcome from the study and exhibited lower value for all the crops. Besides production of food crops, INM also greatly influenced the soil and water characterization and it was favourably reflected in this study. The physico-chemical characteristics of soil (textural class, pH, organic carbon, organic matter, ammoniacal nitrogen, nitrate nitrogen, available nitrogen, phosphorus and potassium) are most important and contributed a significant improvement due to cultivation of these aquatic crops. Analysis of such wet bodies represented the water characteristics (pH, BOD, COD, CO
=3
, HCO
−3
, NO
−3
N, SO
−4
S and Cl−) were most responsive, adaptable and quite favourable for the cultivation of these crops in this vast waste unused wetlands for the mankind without any environmental degradation. 相似文献
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