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1.
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2.
This work was conducted to use palm date wastes in the production of carotenoids. Three strains of Lactobacillus plantarum (QS1, QS2 and QS3) were isolated from food samples including bakery's yeast, olive fermentation and cheese. Strains were investigated for their structural recA gene by PCR. The recA gene was successfully amplified from all strains under study. The ability of isolated L. plantarum strains to produce carotenoids in MRS broth was investigated. QS3 isolate gave the highest ability for production of carotenoids. Statistical screening of media components for production of carotenoids by L. plantarum QS3 using date syrup as a source of sugar was carried out using Plackett-Burman design. Date syrup at 5% sugar concentration produced 16.21 mg/kg dry cell of carotenoids when used alone. Increase in carotenoids production was recovered (54.89 mg/kg dry cell) with supplementation of MRS medium with salts and organic nitrogen after optimization of pH and temperature using date syrup as a carbon source. Plackett-Burman design showed peptone, K2HPO4, sodium acetate and date juice as main components affecting carotenoids production.  相似文献   

3.
Antifungal potential of Streptomyces hygroscopicus metabolites was tested against the isolates of Colletotrichum spp., obtained from rotten apple fruits. Experimental factorial design and response surface methodology were employed to optimize medium composition and enhance antifungal components productivity by S. hygroscopicus. Results of optimization suggest that the optimal medium composition is (g/L): glycerol (13.92), yeast extract (5.00), phosphates (0.63), CaCO3, (3.0), NaCl, (3.0), MgSO4, (0.5). Further research was performed to validate the obtained results and confirm their applicability in planta on artificially inoculated apple fruits. The obtained efficacy after 14 days of incubation was 99.3% against Colletotrichum acutatum and 99.8% against Colletotrichum gloeosporioides. Application of supernatant of S. hygroscopicus cultivation medium, produced under defined conditions, in biological control of apple rot could offer safe and healthy apple fruits on the market, while simultaneously helping to solve the problem of waste glycerol disposal in the biodiesel industry.  相似文献   

4.
The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential.  相似文献   

5.
Brown algae are ubiquitously distributed in the NW coastline of the Iberian Peninsula, where they stand as an underexploited resource. In this study, five solvents were applied to the extraction of pigments from nine brown algae, followed by their determination and quantification by HPLC-DAD. A total of 13 compounds were detected: Six were identified as chlorophylls, six were classified as xanthophylls, and one compound was reported as a carotene. Fucoxanthin was reported in all extracts, which is the most prominent pigment of these algae. Among them, L. saccharina and U. pinnatifida present the highest concentration of fucoxanthin (4.5–4.7 mg∙g−1 dry weight). Ethanol and acetone were revealed as the most efficient solvents for the extraction of pigments, showing a maximal value of 11.9 mg of total pigments per gram of dry alga obtained from the ethanolic extracts of H. elongata, followed by the acetonic extracts of L. ochroleuca. Indeed, ethanol was also revealed as the most efficient solvent according to its high extraction yield along all species evaluated. Our results supply insights into the pigment composition of brown algae, opening new perspectives on their commercial exploitation by food, pharmaceutical, and cosmeceutical industries.  相似文献   

6.
Xanthophylls, a yellow pigment belonging to the carotenoid family, have attracted much attention for industrial applications due to their versatile nature. We report the isolation of a homo xanthophyll pigment-producing marine bacterium, identified as the Erythrobacter sp. SDW2 strain, from coastal seawater. The isolated Erythrobacter sp. SDW2 strain can produce 263 ± 12.9 mg/L (89.7 ± 5.4 mg/g dry cell weight) of yellow xanthophyll pigment from 5 g/L of glucose. Moreover, the xanthophyll pigment produced by the SDW2 strain exhibits remarkable antioxidative activities, confirmed by the DPPH (73.4 ± 1.4%) and ABTS (84.9 ± 0.7%) assays. These results suggest that the yellow xanthophyll pigment-producing Erythrobacter sp. SDW2 strain could be a promising industrial microorganism for producing marine-derived bioactive compounds with potential for foods, cosmetics, and pharmaceuticals.  相似文献   

7.
Porphyridium purpureum is a well-known Rhodophyta that recently has attracted enormous attention because of its capacity to produce many high-value metabolites such as the pigment phycoerythrin and several high-value fatty acids. Phycoerythrin is a fluorescent red protein-pigment commercially relevant with antioxidant, antimicrobial activity, and fluorescent properties. The volumetric mass transfer coefficient (kLa) was kept constant within the different scaling-up stages in the present study. This scaling-up strategy was sought to maintain phycoerythrin production and other high-value metabolites by Porphyridium purpureum, using hanging-bag photobioreactors. The kLa was monitored to ensure the appropriate mixing and CO2 diffusion in the entire culture during the scaling process (16, 80, and 400 L). Then, biomass concentration, proteins, fatty acids, carbohydrates, and phycoerythrin were determined in each step of the scaling-up process. The kLa at 16 L reached a level of 0.0052 s−1, while at 80 L, a value of 0.0024 s−1 was achieved. This work result indicated that at 400 L, 1.22 g L−1 of biomass was obtained, and total carbohydrates (117.24 mg L−1), proteins (240.63 mg L−1), and lipids (17.75% DW) were accumulated. Regarding fatty acids production, 46.03% palmitic, 8.03% linoleic, 22.67% arachidonic, and 2.55% eicosapentaenoic acid were identified, principally. The phycoerythrin production was 20.88 mg L−1 with a purity of 2.75, making it viable for food-related applications. The results of these experiments provide insight into the high-scale production of phycoerythrin via the cultivation of P. purpureum in an inexpensive and straightforward culture system.  相似文献   

8.
The culture supernatant of Paenibacillus sp. TKU036, a bacterium isolated from Taiwanese soils, showed high antioxidant activity (85%) when cultured in a squid pen powder (SPP)-containing medium at 37 °C for three days. Homogentisic acid (2,5-dihydroxyphenylacetic acid, HGA) was isolated and found to be the major antioxidant in the culture supernatant of the SPP-containing medium fermented by Paenibacillus sp. TKU036. Tryptophan was also present in the culture supernatant. The results of high-performance liquid chromatography (HPLC) fingerprinting showed that HGA and tryptophan were produced via fermentation but did not pre-exist in the unfermented SPP-containing medium. Neither HGA nor tryptophan was found in the culture supernatants obtained from the fermentation of nutrient broth or other chitinous material, i.e., medium containing shrimp head powder, by Paenibacillus sp. TKU036. The production of HGA via microorganisms has rarely been reported. In this study, we found that squid pen was a potential carbon and nitrogen source for Paenibacillus sp. Tryptophan (105 mg/L) and HGA (60 mg/L) were recovered from the culture supernatant. The isolated HGA was found to have higher antioxidant activity (IC50 = 6.9 μg/mL) than α-tocopherol (IC50 = 17.6 μg/mL). The anti-inflammatory activity of the isolated HGA (IC50 = 10.14 μg/mL) was lower than that of quercetin (IC50 = 1.14 μg/mL). As a result, squid pen, a fishery processing byproduct, is a valuable material for the production of tryptophan and the antioxidant and anti-inflammatory HGA via microbial conversion.  相似文献   

9.
Artemisinin isolated from the aerial parts of Artemisia annua L. is a promising and potent antimalarial drug. It posses remarkable activity against both chloroquinine resistant as well as chloroquinine sensitive strains of Plasmodium falciparum. It is also useful in the treatment of cerebral malaria. The relatively low content of artemisinin in A. annua and unavailability of cost effective and viable synthetic protocol however, are major obstacles to the commercial production of the drug. The enhanced production of artemisinin is hence, highly desirable, which can be achieved by adequate and judicious supply of plant nutrients. The present experiment was therefore, designed to study the effect of organic manure (15 tonnes ha−1) and chemical fertilizers (N40+40, P40, K40, S15+15 kg ha−1; nitrogen, phosphorus, potassium and sulphur) on the accumulation of artemisinin and biomass in various plant parts through the developmental stages of A. annua L. Artemisinin yield (kg ha−1) was also determined through the developmental stages of A. annua L. Artemisinin content and artemisinin yield of dried leaves were increased significantly at pre-flowering stage in the plants treated with NPKS (27.3% and 53.6%) and NPK (18.2% and 33.5%), respectively, when compared with control. Maximum dry yield of leaf ranging from 2596 to 3141 kg ha−1 was observed at pre-flowering stage with various treatments.  相似文献   

10.
R-phycoerythrin (R-PE), a marine bioactive protein, is abundant in Porphyra yezoensis with high protein content. In this study, R-PE was purified using a deep eutectic solvents aqueous two-phase system (DES-ATPS), combined with ammonium sulphate precipitation, and characterized by certain techniques. Firstly, choline chloride-urea (ChCl-U) was selected as the suitable DES to form ATPS for R-PE extraction. Then, single-factor experiments were conducted: the purity (A565/A280) of R-PE was 3.825, and the yield was 69.99% (w/w) under optimal conditions (adding 0.040 mg R-PE to ChCl-U (0.35 g)/K2HPO4 (0.8 g/mL, 0.5 mL) and extracting for 20 min). The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results revealed that the purified R-PE contained three main bands. One band was presented after purification in native-PAGE. The UV-vis spectra showed characteristic absorption peaks at 495, 540, and 565 nm. R-PE displayed an emission wavelength at 570 nm when excited at 495 nm. All spectra results illustrated that the structure of R-PE remained unchanged throughout the process, proving the effectiveness of this method. Transmission electron microscope (TEM) showed that aggregation and surrounding phenomena were the driving forces for R-PE extraction. This study could provide a green and simple purification method of R-PE in drug development.  相似文献   

11.
The effect of sodium selenite addition and fermentation times on production of selenomethionine (SeM) during sponge bread production was evaluated. Doughs were supplemented with sodium selenite (Na2SeO3) and fermented with yeast, avoiding addition of sulfur salts. The effect of Na2SeO3 on yeast activity was evaluated using a pressurometer. Results showed that there were not statistical differences (p < 0.05) in CO2 production and dough pH at all the sodium selenite concentrations tested. HPLC-fluorescence data showed that SeM production was higher with the increase of fermentation times, while less significant effects were observed due to changes in Na2SeO3 concentration. Two slices of Se-enriched bread can provide about 200 μg SeM, the dose recommended to prevent cancer and oxidative stress. The physical features (water absorption, bread weight, bread volume, color, density, oven spring, etc.) and organoleptic evaluations for the enriched loaves were evaluated. In all these parameters, the experimental enriched breads had practically identical attributes compared to the control. The breads rich in SeM have potential to be used as functional foods because this amino acid is synthesized into higher quantities of glutathione peroxidase, an enzyme considered as one of the most protective mechanisms against oxidative stress and preventive of cancer and chronic diseases.  相似文献   

12.
Three wine-making residues (grape seeds, skins and stems), and corn cobs were evaluated as support material for immobilization of Saccharomyces cerevisiae and the ethanol production by the immobilized cells was assessed. The main objective of this study was to find an abundant and low cost material suitable for the cells immobilization and able to be used in a next step of wine production by immobilized yeast cells. The four natural materials were used as support in two different forms: untreated, and treated by a sequence of acid and basic reactions. Untreated grape skin and corn cobs provided the highest cell immobilization results (25.1 and 22.2 mg cells/g support, respectively). The maximum ethanol production yield (about 0.50 g/g) was also obtained when the cells were immobilized in these untreated materials. It was also found that the support materials released nutrients to the medium, which favored the yeast development and the ethanol production. The use of immobilized cells systems under agitated conditions gave ethanol yields similar to those obtained by the static fermentations, but the immobilized cell concentration was significantly lower. In brief, static fermentation with cells immobilized on grape skins or corn cobs appear to be an interesting alternative for use on wine-making. The use of grape skins, particularly, which is a by-product of the wine elaboration, could be of larger interest to obtain an integrated wine production process with by-product reuse.  相似文献   

13.
In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.  相似文献   

14.
Thraustochytrids are well-known unicellular heterotrophic marine protists because of their promising ability to accumulate docosahexaenoic acid (DHA). However, the implications of their unique genomic and metabolic features on DHA production remain poorly understood. Here, the effects of chemical and physical culture conditions on the cell mass and DHA production were investigated for a unique thraustochytrid strain, PKU#SW8, isolated from the seawater of Pearl River Estuary. All the tested fermentation parameters showed a significant influence on the cell mass and concentration and yield of DHA. The addition of monosaccharides (fructose, mannose, glucose, or galactose) or glycerol to the culture medium yielded much higher cell mass and DHA concentrations than that of disaccharides and starch. Similarly, organic nitrogen sources (peptone, yeast extract, tryptone, and sodium glutamate) proved to be beneficial in achieving a higher cell mass and DHA concentration. PKU#SW8 was found to grow and accumulate a considerable amount of DHA over wide ranges of KH2PO4 (0.125–1.0 g/L), salinity (0–140% seawater), pH (3–9), temperature (16–36 °C), and agitation (140–230 rpm). With the optimal culture conditions (glycerol, 20 g/L; peptone, 2.5 g/L; 80% seawater; pH 4.0; 28 °C; and 200 rpm) determined based on the shake-flask experiments, the cell mass and concentration and yield of DHA were improved up to 7.5 ± 0.05 g/L, 2.14 ± 0.03 g/L, and 282.9 ± 3.0 mg/g, respectively, on a 5-L scale fermentation. This study provides valuable information about the fermentation conditions of the PKU#SW8 strain and its unique physiological features, which could be beneficial for strain development and large-scale DHA production.  相似文献   

15.
A field experiment was carried out to research the changes and spatial distributions of soil nutrients in saline–sodic soil for different number of cultivated years under drip irrigation. The distributions of available potassium (AK), available phosphorus (AP), nitrate nitrogen (NO3 ?–N), ammonium nitrogen (NH4 +–N), as well as the amount of total nitrogen (TN), total phosphorus (TP) and organic carbon (OC) in the 0–40 cm soil layers in saline–sodic soils planted with Leymus chinensis for 1, 2, and 3 years were studied. The results showed that the distance from the emitter had an obvious effect on soil nutrients. Drip irrigation had substantial effects on levels of AK, AP, and NO3 ?–N. The contents of AK, AP, and NO3 ?–N were very high in the area near the emitter in the horizontal direction. In the vertical direction, levels of all of the available and total soil nutrients decreased with increased soil depth. Levels of AK, AP, NO3 ?–N, NH4 +–N, TN, TP, and OC all increased with continued cultivation of crops on saline–sodic soil using drip irrigation. Compared to the nutrients found in soils from the natural L. chinensis grasslands, the contents of AK and TP were higher in the drip-irrigated soils, although the contents of AP, NO3 ?–N, and NH4 +–N were broadly comparable. Given the rate of improvements in nutrient levels, we forecast that the nutrients in drip-irrigated saline–sodic soils should match those of the natural L. chinensis grasslands after 3–6 years of cultivation.  相似文献   

16.
The sulfated polysaccharides from Solieria filiformis (Sf), Botryocladia occidentalis (Bo), Caulerpa racemosa (Cr) and Gracilaria caudata (Gc) were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L.) amazonensis promastigotes. Under the same assay conditions, only three of the four sulfated polysaccharides were active against L. amazonensis, and the polysaccharide purified from Cr was the most potent (EC50 value: 34.5 μg/mL). The polysaccharides derived from Bo and Sf demonstrated moderate anti-leishmanial activity (EC50 values of 63.7 μg/mL and 137.4 μg/mL). In addition, we also performed in vitro cytotoxic assays toward peritoneal macrophages and J774 macrophages. For the in vitro cytotoxicity assay employing J774 cells, all of the sulfated polysaccharides decreased cell survival, with CC50 values of 27.3 μg/mL, 49.3 μg/mL, 73.2 μg/mL, and 99.8 μg/mL for Bo, Cr, Gc, and Sf, respectively. However, none of the sulfated polysaccharides reduced the cell growth rate of the peritoneal macrophages. These results suggest that macroalgae contain compounds with various chemical properties that can control specific pathogens. According to our results, the assayed sulfated polysaccharides were able to modulate the growth rate and cell survival of Leishmania (L.) amazonensis promastigotes in in vitro assays, and these effects involved the interaction of the sulfated polysaccharides on the cell membrane of the parasites.  相似文献   

17.
Mechanisms of action and effectiveness of the antifungal yeast Cryptococcus laurentii [(Kuff.) C.E. Skinner] strain L5D, were examined against the causal agent of anthracnose Colletotrichum gloeosporioides ((Penz.) Penz. & Sacc.) in mango (Mangifera indica L.). C. laurentii showed a high antagonistic potential in vivo, with significant inhibition of anthracnose (75.88%). Different mechanisms of action were examined in C. laurentii among them competition for nutrients, specifically for sucrose (p < 0.05). Scanning Electron Microscopy (SEM) showed that the yeast biofilm adheres to the fruit and to C. gloeosporioides hyphae showing competition for space; C. laurentii was not washed off from treated Colletotrichum hyphae as observed with SEM. According to statistical analysis, only nagase and chitinase were significantly stimulated on wounded fruit. Activity of all three hydrolytic enzymes was detected in vitro but only nagase was induced by addition of autoclaved pathogen mycelium. Treated wounds with the yeast biocontrol stimulated glucanase activity and suppressed chitinase activity on fruit wounds with or without presence of autoclaved pathogen mycelium but did not affect nagase significantly (p = 0.05). Parasitic activity of yeast on pathogen was not detected.  相似文献   

18.
《Field Crops Research》2006,96(1):71-79
A xantha mutant (yellow plant) was induced by gamma rays irradiation of a cytoplasmic male sterile (CMS) maintainer line II32 B of rice (Oryza sativa L.). It was identified earlier as a low gelatinization temperature mutant and named as Mgt-1. Through a series of backcrosses of Mgt-1 to CMS line II32 A, a new CMS line was developed and named as Huangyu A (B). Genetic analysis showed that the xantha mutation was controlled by a single recessive locus, and all F1 plants from crosses of Huangyu A (B) with other normal green varieties showed normal green leaves. The xantha mutation resulted in reduction of photosynthetic pigments content at various levels, e.g., 48% of chlorophyll a (Chl a), 71% of chlorophyll b (Chl b), and 30% of carotenoids (Car), and consequently increased the ratios of Chl a/Chl b and Car/Chl in Huangyu A (B) against II32 A (B). Unexpectedly, Huangyu A (B) had higher photosynthetic rates in comparison with II32 A (B), and so did the F1 plants of Huangyu A/R3027 as against those of II32 A/R3027. Huangyu A had similar male sterility completeness and stability as II32 A, but the former showed significantly better combining ability than the latter. The yellow color made the seedlings and plants of Huangyu A (B) visually distinguishable from the green ones and thus it was a very distinct marker applicable for rapid testing and efficient increasing varietal purity in seed and paddy production of hybrid rice.  相似文献   

19.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

20.
This work investigates the production of hyaluronic acid (H) by Streptococcus equi subsp. zooepidemicus in complex media formulated with peptones obtained from Scyliorhinus canicula viscera by-products. Initially, in batch cultures, the greatest productions were achieved using commercial media (3.03 g/L) followed by peptones from alcalase hydrolyzed viscera (2.32 g/L) and peptones from non-hydrolyzed viscera (2.26 g/L). An increase of between 12% and 15% was found in subsequent fed-batch cultures performed on waste peptones. Such organic nitrogen sources were shown to be an excellent low-cost substrate for microbial H, saving more than 50% of the nutrient costs.  相似文献   

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