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Zhaoling Cai

Publications and source records attributed to Zhaoling Cai.

13 recordsLinked to original sources
PubMed2006

Synergic treatment for monosodium glutamate wastewater by Saccharomyces cerevisiae and Coriolus versicolor.

Biodegradation and decolorization of monosodium glutamate wastewater were carried out by using an acidophilus yeast strain of Saccharomyces cerevisiae and Coriolus versicolor. For the yeast treatment, the highest COD removal and reducing sugar removal efficiency were 76.6% and 80.2%, respectively. The color removal was only 2%. For C. versicolor treatment, the highest COD removal, color removal and reducing sugar removal efficiencies were 78.7%, 56.5% and 90.9%, respectively. The synergic treatment process, in which the yeast and C. versicolor were successively applied,exhibited great advantage over the individual process.

Agaricales↗
PubMed2004

Utilization of nitrite as a nitrogen source by Botryococcus braunii.

Nitrite at 2 mM did not affect the growth of Botryococcus braunii and served as the sole nitrogen source giving a minimum biomass doubling time of 4.2 d, which was equal to that of the culture using 4 mM nitrate as nitrogen source. With nitrite at 4 mM, after a lag phase of about 10 d, the alga grew quickly, reaching 1.1 g l(-1) at the end. Respective nitrite removals were 100% and 99.7%. There were few differences in the hydrocarbons produced using different nitrogen sources.

Bioreactors↗
PubMed2004

Improved use of organic phosphate by Skeletonema costatum through regulation of Zn2+ concentrations.

The maximum growth rate (1.4-2 x 10(5) cells ml(-1) d(-1)), cell final yields (2.6-5.2 x 10(5) cells ml(-1)) and extracellular alkaline phosphatase activity (2.4-10.6 microg phosphate released ml(-1) h(-1)) of the red tide alga, Skeletonema costatum, increased when Zn2+ was increased from 0 to 24 pM, but decreased with 66 pM Zn2+ in growth medium with glycerophosphate as the sole phosphorus source. Extracellular carbonic anhydrase activity and the affinity for HCO3- and CO2 uptake increased when Zn2+ was increased from 0 to 12 pM, but then decreased at higher concentrations. The results suggested that utilization of organic phosphate required more Zn2+ than the uptake of inorganic carbon did, while utilization of dissolved inorganic carbon by Skeletonema costatum was very sensitive to Zn2+ concentration variations.

Alkaline Phosphatase↗
PubMed2004

Interactions between organic and inorganic carbon sources during mixotrophic cultivation of Synechococcus sp.

Glucose at 3 g l(-1) markedly accelerated growth of Synechococcus sp. PCC 7002. The net photosynthesis rate was 263 micromol O2 (mg Chl a h)(-1) for mixotrophic culture and 146 micromol O2 (mg Chl a h)(-1) for photoautotrophic culture. Additing 1 g NaHCO3 l(-1) to the glucose-supplemented culture enhanced the photosynthetic rate by 18%, and the total carbon consumption rate was raised to 2.5 mg l(-1) (mg chl a h)(-1) from a previously negative value. An interaction between organic and inorganic carbon metabolism was established.

Carbon Compounds, Inorganic↗
PubMed2003

Biooxidation of ferrous iron by immobilized Acidithiobacillus ferrooxidans in poly(vinyl alcohol) cryogel carriers.

PVA-cryogels entrapping about 10(9) cells of Acidithiobacillus ferrooxidans per ml of gel were prepared by freezing-thawing procedure, and the biooxidation of Fe2+ by immobilized cells was investigated in a 0.365 l packed-bed bioreactor. Fe2+ oxidation fits a plug-flow reaction model well. A maximum oxidation rate of 3.1 g Fe2+ l(-1) h(-1) was achieved at the dilution rate of 0.4 h(-1) or higher, while no obvious precipitate was determined at this time. In addition, cell-immobilized PVA-cryogels packed in bioreactor maintained their oxidative ability for more than two months under non-sterile conditions.

Bioreactors↗
PubMed2003

Growth and photosynthesis limitation of marine red tide alga Skeletonema costatum by low concentrations of Zn2+.

The specific growth rate, cell final yields and extracellar carbonic anhydrase activity of the red tide alga Skeletonema costatum increased with increasing concentrations of Zn2+ from 0 to 12 pM, but decreased when Zn2+ was over 24 pM. However, cells grown under high concentrations of Zn2+ had higher activities of intracellular carbonic anhydrase than those grown under low concentrations of Zn2+. Chlorophyll a-specific light-saturated photosynthetic rate (P(Chla)), dark respiration rate (R(chla)) and apparent photosynthetic efficiency (alpha(chla)) significantly increased with increasing concentrations of Zn2+ from 0 to 3 pM, but decreased when increasing concentrations of Zn2+ from 3 to 66 pM. Photorespiration is the lowest when cells cultured in 3 pM Zn2+. The results suggest physiological activity of Skeletonema costatum is very sensitive to the prevailing concentration of Zn2+.

Carbonic Anhydrases↗
PubMed2003

[Response of Prorocentrum minimum growth to zinc limitation].

Studies on the growth and physiological response of red tide alga Prorocentrum minimum to three Zn2+ levels were showed that the specific growth rate and biomass were limited in low Zn(2+)-grown cells (1.4 pmol.L-1, which were 0.40 d-1 and 51,100 cell.ml-1 respectively. The specific growth rate was not significantly different when the Zn2+ concentration in medium was increased over 24.4 pmol.L-1, but there was a slight decrease in biomass; however, both specific growth rate and biomass were much higher than those in low Zn(2+)-grown cells. It was also showed that chlorophyll a synthesis was limited due to Zn2+ deficient, and therefore, the cells became light saturated at higher irradiance under Zn-limited condition. Light-saturated photosynthetic rates (Pm) and photosynthetic efficiency (alpha) increased significantly with increasing Zn2+ concentrations. It was concluded that Zn2+ concentration might be one of the key factors affecting red tide blooms in eutrophication environment.

Biomass↗
PubMed2003

[Nitrogen and phosphorus absorption and growth characteristics of Alexandrium tamarense].

The uptake of nitrate and phosphate by Alexandrium tamarense and its growth characteristics were studied in laboratory cultures, which were conducted using environmentally realistic levels of physical factors during red tide occurrences. The results indicated that the specific growth rate had little difference under three nitrate levels (low-nitrate, 0.0882 mmol.L-1; middle-nitrate, 0.882 mmol.L-1; high-nitrate, 2.646 mmol.L-1). The cell yield was the lowest at low-nitrate, a maximum yield was achieved at the middle-nitrate, which increased by 44.7% and 53.6% respectively, compared with high-nitrate and low-nitrate. The cell yield increased with increasing phosphate concentrations in cultures (low-phosphate, 0.0036 mmol.L-1; middle-phosphate, 0.036 mmol.L-1; high-phosphate, 0.108 mmol.L-1), and the maximum yield (17200 cell.ml-1) was observed at high-phosphate concentration, while the maximum specific growth rate occurred at middle-phosphate. The growth conditions had a significant effect on the uptake rate of nitrate and phosphate by cells, and the cells grown in low-nitrate and low-phosphate cultures had a higher uptake rate. Further experiment suggested that lower ratio of N/P promoted the propagation of cells, and the supplementation of nitrate at later exponential growth phase had a positive effect to the accumulation of biomass.

Absorption↗
PubMed2003

[Spectroscopic properties of Heterosigma akashiwo under iron limitation].

Room-temperature absorption spectra of H. akashiwo cells under iron limitation showed a chlorophyll c absorption peak at 630 nm, 2 nm blue-shifted from its normal position of 632 nm. Moreover, because of the increase in the relative carotenoid abundance compared to Chl a, there was an extra shoulder peak at 480 nm for the iron-limited cells. Their fluorescence spectra (77 K) have one prominent chlorophyll emission peak at 685 nm. By comparison with Fe-replete cells (10 mumol.L-1), the fluorescence yield from 685 nm band increased by about 2 times in Fe deplete cells (5 nmol.L-1), and about 1.4 times in low iron cells (100 nmol.L-1), respectively. 48 h after Fe addition, the height of 685 nm peak was considerably decreased from that observed in low iron (100 nmol.L-1) and iron deficient (ID) cells before Fe addition, which indicated that there was a significantly higher energy dissipation, and thus, a less effective photosynthesis under the lack of Fe.

Chlorophyll↗
PubMed2003

[Induction of biochemical composition in Heterosigma akashiwo under Fe stress].

The iron-stress mediated effects on biochemical constituents of red tide alga H. akashiwo were examined in Fe-replete and iron deficiency, and low iron batch cultures. The content of all pigments decreased under iron limitation, and the cellular chlorophyll a concentration decreased by more than 2-fold compared to that under iron replete condition. This change in Chl a was accompanied by a corresponding decrease in Chl c per cell, resulting in no trend in the ratio of Chl c to Chl a. The cellular carotenoids content decreased by more than 1.5-fold compared to that under iron replete condition. As a consequence, carotenoids/chlorophyll a ratio increased in Fe-deficient cells. Carbohydrate content was reduced under iron stress, and total proteins decreased with the decrease of iron concentration. A crude fractionation of the soluble proteins demonstrated that 17 kD and 55 kDa proteins in soluble fraction were induced.

Carotenoids↗
PubMed2002

Optimization of a cultural medium for bacteriocin production by Lactococcus lactis using response surface methodology.

The medium composition for bacteriocin production by Lactococcus lactis ATCC 11454 was optimized using response surface methodology. The selected six factors based on CM medium were sucrose, soybean peptone, yeast extract, KH(2)PO(4), NaCl, and MgSO(4).7H(2)O. Fractional factorial designs (FFD) and the path of steepest ascent were effective in searching for the main factors and approaching the optimum region of the response. By a 2(6-2) FFD, sucrose, soybean peptone, yeast extract, KH(2)PO(4) were found to be significant factors and had positive effects on cell growth, however, only soybean peptone and KH(2)PO(4) were shown to be the two significant factors for bacteriocin production and had negative and positive effects, respectively. The effects of the two main factors on bacteriocin production were further investigated by a central composite design and the optimum composition was found to be 1% sucrose, 0.45% soybean peptone, 1% yeast extract, 2.84% KH(2)PO(4), 0.2% NaCl, and 0.02% MgSO(4) x 7H(2)O. The optimal medium allowed bacteriocin yield to be doubled compared to CM medium.

Bacteriocins↗