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1.
Hikoto Ohta Yasuo Seto Noriko Tsunoda 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,691(2):527
Determination of four toxic Aconitum alkaloids, aconitine, mesaconitine, hypaconitine and jesaconitine, in blood and urine samples has been established using high-performance liquid chromatography (HPLC) combined with ultraviolet absorbance detection, solid-phase extraction and mass spectrometry (MS). These alkaloids were hydrolyzed rapidly in alkaline solution (half lives (t1/2)<one day), were stable in solutions of acetonitrile, tetrahydrofuran and diluted hydrochloric acid (t1/2>five months) and were unstable in solutions of methanol and ethanol (t1/2<one month). These alkaloids were separated on an octadecylsilica column with isocratic elution using a solvent mixture of tetrahydrofuran and 0.2% trifluoroacetic acid (14:86, v/v), which was found to be the optimal solvent of the elution systems examined. Calibration curves with UV detection were linear on injection of amounts ranging from 2.5 to 500 ng, and the limit of detection was 1 ng (S/N = 3). These four alkaloids in aqueous solution were recovered almost totally by solid-phase extraction using the styrene polymer resin, Sep-Pak Plus PS-1, and were eluted using a mixture of acetonitrile and hydrochloric acid. These Aconitum alkaloids were confirmed by HPLC coupled with fast atom bombardment MS, giving their protonated molecular ions as base peaks. These alkaloids were detected by HPLC with UV detection from blood samples spiked with more than 50 ng ml−1 of alkaloids, but were not detectable from urine samples spiked with 5 μg ml−1 of alkaloids because of severe sample interference. 相似文献
2.
Acid hydrolysis of sugarcane bagasse for lactic acid production 总被引:3,自引:0,他引:3
Pattana Laopaiboon Arthit Thani Vichean Leelavatcharamas Lakkana Laopaiboon 《Bioresource technology》2010,101(3):1036-1043
In order to use sugarcane bagasse as a substrate for lactic acid production, optimum conditions for acid hydrolysis of the bagasse were investigated. After lignin extraction, the conditions were varied in terms of hydrochloric (HCl) or sulfuric (H2SO4) concentration (0.5–5%, v/v), reaction time (1–5 h) and incubation temperature (90–120 °C). The maximum catalytic efficiency (E) was 10.85 under the conditions of 0.5% of HCl at 100 °C for 5 h, which the main components (in g l−1) in the hydrolysate were glucose, 1.50; xylose, 22.59; arabinose, 1.29; acetic acid, 0.15 and furfural, 1.19. To increase yield of lactic acid production from the hydrolysate by Lactococcus lactis IO-1, the hydrolysate was detoxified through amberlite and supplemented with 7 g l−1 of xylose and 7 g l−1 of yeast extract. The main products (in g l−1) of the fermentation were lactic acid, 10.85; acetic acid, 7.87; formic acid, 6.04 and ethanol, 5.24. 相似文献
3.
Ultrasonic-assisted extraction (UAE) was developed to extract phenolic and flavonoid antioxidants from Clerodendrum cyrtophyllum Turcz leaves. The optimal experimental parameters for antioxidant extraction from C. cyrtophyllum leaves were measured using single-factor experimentation combined with response surface methodology (RSM). Total phenolic content (TPC) and total flavonoid content (TFC) assays were used to quantify antioxidant compounds. Next, antioxidant radical scavenging capacity was measured using 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′ -azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) radicals. Optimized extraction conditions for UAE from C. cyrtophyllum leaves were as follows: 60.9% ethanol, 85.4 min, and 63.3°C for maximal TPC extraction (16.8±0.2 mg GAE/g DW); 67.7% ethanol, 82.9 min, and 63.0°C for maximal TFC extraction (49.3±0.4 mg RT/g DW); 48.8% ethanol, 85.1 min, and 63.9°C for maximal DPPH radical-scavenging capacity (86.8±0.2%); and 50.6% ethanol, 81.3 min, and 63.4°C for maximal ABTS radical-scavenging capacity (92.9±0.5%). Ethanol concentration was the most important factor in the extraction process. Our work offers optimal extraction conditions for C. cyrtophyllum as a potential source of natural antioxidants. 相似文献
4.
Seo HB Kim HJ Lee OK Ha JH Lee HY Jung KH 《Journal of industrial microbiology & biotechnology》2009,36(2):285-292
A method for measuring the ethanol concentration in a yeast culture broth was developed using both microtubes and a 96-deepwell
microplate. The strategy involved first the solvent extraction of ethanol from the yeast culture broth and measurements of
the ethanol concentration using the dichromate oxidation method. Particular focus was made on selecting the extraction solvent
as well as determining the measurable range of ethanol concentrations using this solvent extraction-dichromate oxidation method.
This method was developed as an assay format in 2.0-ml microtubes and 1.2-ml 96-deepwell microplates, and the ethanol concentration
in the batch cultures and fed-batch fermentations was measured. Tri-n-butyl phosphate [non-alcoholic solvent, density = 0.9727, solubility in water = 0.028% (w/v)] was used for solvent extraction
when measuring the ethanol concentration from the yeast culture broth. The maximum detectable ethanol concentration was 8%
(v/v) when 10 g potassium dichromate in 100 ml of 5 M sulfuric acid was used. The concentrations determined from the solvent
extraction-dichromate oxidation methods were remarkably similar to those of gas chromatography in which samples were prepared
from seven experiments, such as four batch cultures and three fed-batch fermentations. 相似文献
5.
Determination of trace lead in biological and water samples with dispersive liquid-liquid microextraction preconcentration 总被引:4,自引:0,他引:4
A new method for the determination of trace lead was developed by dispersive liquid–liquid microextraction preconcentration and graphite furnace atomic absorption spectrometry. In the proposed approach, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was used as a chelating agent, and carbon tetrachloride and ethanol were selected as extraction and dispersive solvents. Some factors influencing the extraction efficiency of lead and its subsequent determination, including extraction and dispersive solvent type and volume, pH of sample solution, concentration of the chelating agent, and extraction time, were studied and optimized. Under the optimum conditions, the enrichment factor of this method for lead was reached at 78. The detection limit for lead was 39 ng L−1 (3σ), and the relative standard deviation (RSD) was 3.2% (n = 7, c = 10 ng mL−1). The method was successfully applied to the determination of trace amounts of lead in human urine and water samples. 相似文献
6.
Ok-Hwan Lee Boo-Yong Lee Junsoo Lee Hee-Bong Lee Jong-Youn Son Cheon-Seok Park Kalidas Shetty Young-Cheul Kim 《Bioresource technology》2009,100(23):6107-6113
Recent studies suggest that olive leaf is a significant source of bioactive phenolic compounds comparable to olive oil and fruits. Identifying appropriate extraction methods is thus an important step to increase the yield of such bioactive components from olive leaf, which is otherwise agricultural waste. The present study evaluates phenolic contents and compositions of olive leaf extracted by several solvent methods and to further establish their antioxidant activities using various radical scavenging systems. Total flavonoid and phenolic contents were significantly higher in the 80% ethanol extract, butanol, and ethylacetate fractions than hexane, chloroform and water fractions (p < 0.05). Oleuropein was identified as a major phenolic compound with considerable contents in these major three fractions and the extract that correlated with their higher antioxidant and radical scavenging. These results indicate that olive leaf contains significant amounts of oleuropein and phenolics, important factors for antioxidant capacity, which can be substantially modified by different extraction methods. 相似文献
7.
Marcia Da Silva Pinto Young-In Kwon Emmanouil Apostolidis Franco Maria Lajolo Maria Ins Genovese Kalidas Shetty 《Bioresource technology》2009,100(24):6599-6609
Leaves from four different Ginkgo biloba L. trees (1 and 2 – females; 3 and 4 – males), grown at the same conditions, were collected during a period of 5 months (from June to October, 2007). Water and 12% ethanol extracts were analyzed for total phenolics content, antioxidant activity, phenolic profile, and the potential in vitro inhibitory effects on α-amylase, α-glucosidase, and Angiotensin I-Converting Enzyme (ACE) enzymes related to the management of diabetes and hypertension. The results indicated a significant difference among the trees in all functional benefits evaluated in the leaf extracts and also found important seasonal variation related to the same functional parameters. In general, the aqueous extracts had higher total phenolic content than the ethanolic extracts. Also, no correlation was found between total phenolics and antioxidant activity. In relation to the ACE inhibition, only ethanolic extracts had inhibitory activity. 相似文献
8.
The aim of this study was to compare the performance of the enzymes produced by Trichoderma reesei Rut C30 and the good extracellular β-glucosidase-producing mutant Trichoderma atroviride TUB F-1663 to that of commercial preparations in the enzymatic hydrolysis and the simultaneous saccharification and fermentation (SSF) of steam-pretreated spruce (SPS).The concentrated TUB F-1663 enzyme was found to be the most efficient in the hydrolysis of washed SPS at 50 g/L water-insoluble solids (WIS) in terms of the glucose produced (18.5 g/L), even in comparison with commercial cellulases (14.1–16.7 g/L). The enzyme preparations were studied at low enzyme loadings (5 FPU/g WIS) in SSF to produce ethanol from SPS. The enzyme supernatant and whole fermentation broth of T. atroviride as well as the whole broth of T. reesei proved to be as efficient in SSF as the commercial cellulase mixtures (ethanol yields of 61–76% of the theoretical were achieved), while low ethanol yields (<40%) were obtained with the β-glucosidase-deficient T. reesei supernatant.Therefore, it seems, that instead of using commercial cellulases, the TUB F-1663 enzymes and the whole broth of Rut C30 may be produced on-site, using a process stream as carbon source, and employed directly in the biomass-to-bioethanol process. 相似文献
9.
Wang Yongjiang Cheng Zhong Mao Jianwei Fan Minger Wu Xueqian 《Carbohydrate polymers》2009,77(4):713-717
Polysaccharides production from Poria cocos was carried out using aqueous NaOH with the assistance of ultrasonic. Experimental design was used to investigate the effect of three parameters (extraction time, extraction concentration of NaOH, and ratio of aqueous NaOH to raw material) on polysaccharides yields. The ranges of the factors investigated were 1–3 min for extraction time (X1), 0.5–1.0 mol/L for extraction concentration of NaOH (X2), and 30–50 for ratio of aqueous NaOH to raw material (X3). The statistical analysis of the experiment indicated that extraction concentration of NaOH had significant effect on P. cocos polysaccharides yields. The central composite design showed that polynomial regression models were in good agreement with the experimental results with the coefficients of determination of 0.9935 for P. cocos polysaccharides yield. The optimal condition for P. cocos polysaccharides yield within the experimental range of the variables studied was at 2.44 min, 0.789 mol/L, and 53.0. At this condition, the predicted yield of polysaccharides extracted was 82.3%. 相似文献
10.
Allelopathic Effects,Physiological Responses and Phenolic Compounds in Litter Extracts of Juniperus rigidaSieb. et Zucc.
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The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter. 相似文献
11.
Zora Vradyov Svetlana Kiidayov Peter Siroka Duan Jal
《Animal Feed Science and Technology》2008,144(1-2):44-54
The objective of this study was to investigate effects of oil supplements on the composition of fatty acids (FA), especially of trans11-C18:1 (vaccenic acid, TVA) and cis9, trans11-C18:2 conjugated linoleic acid (c9,t11-CLA), in bacterial (BF) and protozoal (PF) fractions of rumen fluid of sheep that was fractionated centrifugation. Four sheep were fed a diet consisting of meadow hay (960 g dry matter (DM)/day) and of barley grain (240 g DM/day), with sunflower oil (SO), rapeseed oil (RO) or linseed oil (LO) as supplements (60 g/day) in a Latin square design. The oils were used as they are rich in linoleic acid (SO, 533 g/kg of FA), oleic acid (RO, 605 g/kg of FA) and α-linolenic acid (LO, 504 g/kg of FA). Compared to the control (i.e., without oils), oil supplements influenced the concentration of unsaturated (UFA) and saturated fatty acids (SFA). In both BF and PF, the main fatty acids were palmitic and stearic, but PF contained a higher proportion of TVA and c9,t11-CLA than BF. In PF, TVA concentrations, ranked by oil supplement, were SO > RO > LO > Control (174, 150, 118, 74 g/kg of FA, respectively) and the c9,t11-CLA concentrations were RO > SO > LO > Control (59, 51, 27 and 15 g/kg of FA, respectively). Concentrations of c9,t11-CLA in PF were two to three times higher than in BF with all the oil supplements versus the control. Oil treatments impacted the c9,t11-CLA concentration in the fractions, especially SO and RO. The protozoal fraction contained a higher proportion of TVA and c9,t11-CLA than did the bacterial fraction, and dietary addition of SO, RO and LO resulted in a higher incorporation of TVA into both bacterial and protozoal microbial fractions, which probably positively affected TVA flow from the rumen. 相似文献
12.
Simultaneous saccharification and ethanol fermentation of oxalic acid pretreated corncob assessed with response surface methodology 总被引:1,自引:0,他引:1
Response surface methodology was used to evaluate optimal time, temperature and oxalic acid concentration for simultaneous saccharification and fermentation (SSF) of corncob particles by Pichia stipitis CBS 6054. Fifteen different conditions for pretreatment were examined in a 23 full factorial design with six axial points. Temperatures ranged from 132 to 180 °C, time from 10 to 90 min and oxalic acid loadings from 0.01 to 0.038 g/g solids. Separate maxima were found for enzymatic saccharification and hemicellulose fermentation, respectively, with the condition for maximum saccharification being significantly more severe. Ethanol production was affected by reaction temperature more than by oxalic acid and reaction time over the ranges examined. The effect of reaction temperature was significant at a 95% confidence level in its effect on ethanol production. Oxalic acid and reaction time were statistically significant at the 90% level. The highest ethanol concentration (20 g/l) was obtained after 48 h with an ethanol volumetric production rate of 0.42 g ethanol l−1 h−1. The ethanol yield after SSF with P. stipitis was significantly higher than predicted by sequential saccharification and fermentation of substrate pretreated under the same condition. This was attributed to the secretion of β-glucosidase by P. stipitis. During SSF, free extracellular β-glucosidase activity was 1.30 pNPG U/g with P. stipitis, while saccharification without the yeast was 0.66 pNPG U/g. 相似文献
13.
Eliane M.Z. Michielin Ana A. Salvador Carlos A.S. Riehl Artur Smnia Jr. Elza F.A. Smnia Sandra R.S. Ferreira 《Bioresource technology》2009,100(24):6615-6623
The present study describes the chemical composition and the antibacterial activity of extracts from Cordia verbenacea DC (Borraginaceae), a traditional medicinal plant that grows widely along the southeastern coast of Brazil. The extracts were obtained using different extraction techniques: high-pressure operations and low-pressure methods. The high-pressure technique was applied to obtain C. verbenacea extracts using pure CO2 and CO2 with co-solvent at pressures up to 30 MPa and temperatures of 30, 40 and 50 °C. Organic solvents such as n-hexane, ethyl acetate, ethanol, acetone and dichloromethane were used to obtain extracts by low-pressure processes. The antibacterial activity of the extracts was also subjected to screening against four strains of bacteria using the agar dilution method. The extraction yields were up to 5.0% w/w and up to 8.6% w/w for supercritical fluid extraction with pure CO2 and with ethyl acetate as co-solvent, respectively, while the low-pressure extraction indicates yields up to 24.0% w/w in the soxhlet extraction using water and aqueous mixture with 50% ethanol as solvents. The inhibitory activity of the extracts in Gram-positive bacteria was significantly higher than in Gram-negative. The quantification and the identification of the extracts recovered were accomplished using GC/MS analysis. The most important components identified in the extract were artemetin, β-sitosterol, α-humulene and β-caryophyllene, among others. 相似文献
14.
Jorge F. Toro-Vazquez Maritza Alonzo-Macias Elena Dibildox-Alvarado Miriam A. Charó-Alonso 《Food biophysics》2009,4(3):199-212
The effect of tripalmitin (TP) crystallization on the thermomechanical properties of organogels developed with candelilla
wax (CW) was investigated using safflower oil high in triolein (HOSFO) as the liquid phase. Factorial combinations of CW (i.e.,
0–3%) and TP (i.e., 0–1%) in the HOSFO were used to develop organogels at three different temperatures (T
set). The onset of crystallization (T
g) during the cooling stage (10 °C/min), the melting temperature (T
M), and the corresponding heat of melting (ΔH
M) of the organogels were determined by differential scanning calorimetry. Results showed that, without CW, the crystallization
of TP in the HOSFO at the concentrations and T
set investigated (i.e., −10 °C to 25 °C) did not develop a three-dimensional network that provided significant viscoelasticity
(i.e., solid-like behavior) to the HOSFO. The CW developed organogels in the HOSFO with T
M’s that increased from ≈30.5 °C up to ≈42.5 °C as a function of CW concentration. In contrast, in the CW–1% TP system, the
co-crystallization of TP and CW resulted in organogels with TM’s that varied just between 36 °C and 38 °C, independent of the CW concentration. Higher elastic modulus (G′) and yield stress
(σ*) were obtained with 3% CW–1.0% TP organogels than with organogels developed just by CW, particularly at T
set’s of −5 °C and 15 °C. This research showed that co-crystallization of TP and CW, occurring at different extent as a function
of T
set, resulted in organogels with thermomechanical properties different from the ones showed by CW organogels. The results showed
that co-crystallization of triacylglycerides with CW might be a useful alternative to tailor particular physicochemical properties
associated to a specific functionality (i.e., melting profile and texture). Organogelation of vegetable oil might be used
to develop trans-free vegetable-oil-based spreads and coatings and also novel food products with new textural perceptions for the consumers. 相似文献
15.
Lei Jiao Da-Peng Cao Lu-Ping Qin Ting Han Qiao-Yan Zhang Zheng Zhu Fei Yan 《Phytomedicine》2009,16(9):874-881
Six phenolic compounds isolated from Curculigo orchioides, including 2,6-dimethoxy benzoic acid (1), curculigoside A (2), curculigoside B (3), curculigine A (4), curculigine D (5) and 3,3′,5,5′-tetramethoxy-7,9′:7′,9-diepoxylignan-4,4′-di-O-β-d-glucopyranoside (6), together with the ethanol extract of Curculigo orchioides were evaluated for their activity on osteoblasts in neonatal rat calvaria cultures and multinucleated osteoclasts derived from rat marrow cells so as to characterize the antiosteoporotic components of this plant and explore the relationship of chemical structure with antiosteoporotic activity. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP (alkaline phosphatase) and TRAP (tartrate-resistant acid phosphatase) was measured by p-nitrophenyl sodium phosphate assay. The TRAP stain was used to identify osteoclast in morphology. The resorption pit area on the bone slices formed by osteoclast was measured by computer image processing. The ethanol extract exhibited stimulatory effect on both the osteoblast proliferation and the ALP activity. Six compounds all increased the osteoblast proliferation, and compounds (1), (2) and (4) also slightly increased the osteoblastic ALP activity. Compounds (1), (2), (3), (6) and the ethanol extract decreased area of bone resorption pit, osteoclastic formation and TRAP activity. These results indicated that phenolic compounds are antiosteoporotic chemical constituents from Curculigo orchioides, and their activities are related with chemical structures. 相似文献
16.
J.D. van der Merwe E. Joubert E.S. Richards M. Manley P.W. Snijman J.L. Marnewick W.C.A. Gelderblom 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2006,611(1-2):42-53
Antimutagenic activity of aqueous extracts of the South African herbal teas, Aspalathus linearis (rooibos) and Cyclopia spp. (honeybush) was compared with that of Camellia sinensis (black, oolong and green) teas in the Salmonella mutagenicity assay using aflatoxin B1 (AFB1) and 2-acetylaminofluorene (2-AAF) as mutagens. The present study presents the first investigation on antimutagenic properties of C. subternata, C. genistoides and C. sessiliflora. The herbal teas demonstrated protection against both mutagens in the presence of metabolic activation, with the exception of “unfermented” (green/unoxidised) C. genistoides against 2-AAF, which either protected or enhanced mutagenesis depending on the concentration. Antimutagenic activity of “fermented” (oxidised) rooibos was significantly (P < 0.05) less than that of Camellia sinensis teas against AFB1, while for 2-AAF it was less (P < 0.05) than that of black tea and similar (P > 0.05) to that of oolong and green teas. Antimutagenic activity of unfermented C. intermedia and C. subternata exhibited a similar protection as fermented rooibos against AFB1. Against 2-AAF, fermented rooibos exhibited similar protective properties than unfermented C. intermedia and C. sessiliflora. Unfermented rooibos was less effective than the C. sinensis teas and fermented rooibos, but had similar (P > 0.05) antimutagenicity to that of fermented C. sessiliflora against AFB1 and fermented C. subternata against 2-AAF. Fermented C. intermedia and C. genistoides exhibited the lowest protective effect against 2-AAF, while fermented C. intermedia exhibited the lowest protection when utilising AFB1 as mutagen. Aspalathin and mangiferin, major polyphenols in rooibos and Cyclopia spp., respectively, exhibited weak to moderate protective effects when compared to the major green tea catechin, (−)epigallocatechin gallate (EGCG). Antimutagenic activity of selected herbal tea phenolic compounds indicated that they contribute towards (i) observed antimutagenic activity of the aqueous extracts against both mutagens and (ii) enhancement of the mutagenicity of 2-AAF by unfermented C. genistoides. Antimutagenic activity of the South African herbal teas was mutagen-specific, affected by fermentation and plant material, presumably due to changes and variation in phenolic composition. 相似文献
17.
Identification and characterization of fermentation inhibitors formed during hydrothermal treatment and following SSF of wheat straw 总被引:1,自引:0,他引:1
Mette Hedegaard Thomsen Anders Thygesen Anne Belinda Thomsen 《Applied microbiology and biotechnology》2009,83(3):447-455
A pilot plant for hydrothermal treatment of wheat straw was compared in reactor systems of two steps (first, 80°C; second,
190–205°C) and of three steps (first, 80°C; second, 170–180°C; third, 195°C). Fermentation (SSF) with Sacharomyces cerevisiae of the pretreated fibers and hydrolysate from the two-step system gave higher ethanol yield (64–75%) than that obtained from
the three-step system (61–65%), due to higher enzymatic cellulose convertibility. At the optimal conditions (two steps, 195°C
for 6 min), 69% of available C6-sugar could be fermented into ethanol with a high hemicellulose recovery (65%). The concentration
of furfural obtained during the pretreatment process increased versus temperature from 50 mg/l at 190°C to 1,200 mg/l at 205°C
as a result of xylose degradation. S. cerevisiae detoxified the hydrolysates by degradation of several toxic compounds such as 90–99% furfural and 80–100% phenolic aldehydes,
which extended the lag phase to 5 h. Acetic acid concentration increased by 0.2–1 g/l during enzymatic hydrolysis and 0–3.4 g/l
during fermentation due to hydrolysis of acetyl groups and minor xylose degradation. Formic acid concentration increased by
0.5–1.5 g/l probably due to degradation of furfural. Phenolic aldehydes were oxidized to the corresponding acids during fermentation
reducing the inhibition level. 相似文献
18.
Three different earthworm species Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus in individual (Monocultures) and combinations (Polycultures) were utilized to compare the suitability of worm species for vermicomposting of filter mud as well as the quality of the end product. The filter mud blended with saw dust can be directly converted into good quality fertilizer (vermicompost). Eight different reactors including three monocultures and four polycultures of E. fetida, E. eugeniae and P. excavatus and one control were used for the experiment. Vermicomposting resulted in significant reduction in C/N ratio, pH, total organic matter (TOC) but increase in electrical conductivity (EC), total nitrogen (TN), total phosphorus (TP) and macronutrients (K, Ca and Na). Oxygen uptake rate (OUR) dropped up to 1.64–1.95 mg/g (volatile solids) VS/day for monoculture reactors and 1.45–1.78 mg/g VS/day for polycultures reactors, respectively, after 45 days of vermicomposting. Cocoon production and the earthworm biomass increased as vermicomposting progressed. On an overall the mono as well as polyculture reactors produced high quality stable compost free from pathogens and no specific differentiation could be inferred between the reactors. 相似文献
19.
Zayneb Hayder Walid Elfalleh Khadija Ben Othman Mohamed Ali Benabderrahim Hédia Hannachi 《农业工程》2021,41(2):150-156
There is a growing request to find an effective method of polyphenols extraction from agro-industry by-product as pomegranate. In this study, response surface methodology (RSM) was used to explore the effect of three factors on ultrasonic assisted extraction (UAE) of total polyphenols (TP), total flavonoids (TF) and condensed tannins (CT) from pomegranate peels. The optimal conditions were determined for each phenolic compound using regression model equations and 3-D plots. The high TP, TF and CT content were obtained with, respectively, liquid/solid ratio of 20.00, 9.77, 9.77, extraction time of 36.38, 41.82, 30.39 min and 36.00, 83.64, 59.26% of ethanol percentage. In fact, liquid/solid ratio of 20, extraction time of 30.94 min and 59.26% of ethanol gives the highest contents of TP, TF and CT simultaneously. The experimental values using optimal conditions agreed with the predicted values. The pomegranate peels extract obtained under optimum conditions have an effective antioxidant activity as determined by ABTS and DPPH assays. 相似文献
20.
Patrik R. Lennartsson Keikhosro Karimi Lars Edebo Mohammad J. Taherzadeh 《Journal of biotechnology》2009,143(4):255-261
The dimorphic fungus Mucor indicus was grown in different forms classified as purely filamentous, mostly filamentous, mostly yeast-like and purely yeast-like, and the relationship between morphology and metabolite production, inhibitor tolerance and the cell wall composition was investigated. Low concentrations of spores in the inoculum with subsequent aeration promoted filamentous growth, whereas higher spore concentrations and anaerobic conditions promoted yeast-like growth. Ethanol was the main metabolite with glycerol next under all conditions tested. The yields of ethanol from glucose were between 0.39 and 0.42 g g−1 with productivities of 3.2–5.0 g l−1 h−1. The ethanol productivity of mostly filamentous cells was increased from 3.9 to 5.0 g l−1 h−1 by the presence of oxygen, whereas aeration of purely yeast-like cells showed no such effect. All growth forms were able to tolerate 4.6 g l−1 furfural and 10 g l−1 acetic acid and assimilate the sugars, although with different consumption rates. The cell wall content of the fungus measured as alkali insoluble materials (AIM) of the purely yeast-like cells was 26% of the biomass, compared to 8% of the pure filaments. However, the chitosan concentration of the filaments was 29% of the AIM, compared to 6% of the yeast-like cells. 相似文献