Breeding of Chlorella mutants deficient in chlorophyll synthesis and evaluation of its protein yield and quality / 生物工程学报

The aim of this study was to construct Chlorella mutants deficient in chlorophyll synthesis by atmospheric pressure room temperature plasma (ARTP) mutagenesis, and screen novel algal species with very low chlorophyll content which is suitable for protein production by fermentation. Firstly, the lethal rate curve of mixotrophic wild type cells was established by optimizing the mutagenesis treatment time. The mixotrophic cells in early exponential phase were treated by the condition of over 95% lethal rate, and 4 mutants with the visual change of colony color were isolated. Subsequently, the mutants were cultured in shaking flasks heterotrophically for evaluation of their protein production performance. P. ks 4 mutant showed the best performance in Basal medium containing 30 g/L glucose and 5 g/L NaNO3. The protein content and productivity reached 39.25% dry weight and 1.15 g/(L·d), with an amino acid score of 101.34. The chlorophyll a content decreased 98.78%, whereas chlorophyll b was not detected, and 0.62 mg/g of lutein content made the algal biomass appear golden yellow. This work provides a novel germplasm, the mutant P. ks 4 with high yield and high quality, for alternative protein production by microalgal fermentation.

Chlorella sp.-ameliorated undesirable microenvironment promotes diabetic wound healing

Chronic diabetic wound remains a critical challenge suffering from the complicated negative microenvironments, such as high-glucose, excessive reactive oxygen species (ROS), hypoxia and malnutrition. Unfortunately, few strategies have been developed to ameliorate the multiple microenvironments simultaneously. In this study, Chlorella sp. (Chlorella) hydrogels were prepared against diabetic wounds. In vitro experiments demonstrated that living Chlorella could produce dissolved oxygen by photosynthesis, actively consume glucose and deplete ROS with the inherent antioxidants, during the daytime. At night, Chlorella was inactivated in situ by chlorine dioxide with human-body harmless concentration to utilize its abundant contents. It was verified in vitro that the inactivated-Chlorella could supply nutrition, relieve inflammation and terminate the oxygen-consumption of Chlorella-respiration. The advantages of living Chlorella and its contents were integrated ingeniously. The abovementioned functions were proven to accelerate cell proliferation, migration and angiogenesis in vitro. Then, streptozotocin-induced diabetic mice were employed for further validation. The in vivo outcomes confirmed that Chlorella could ameliorate the undesirable microenvironments, including hypoxia, high-glucose, excessive-ROS and chronic inflammation, thereby synergistically promoting tissue regeneration. Given the results above, Chlorella is considered as a tailor-made therapeutic strategy for diabetic wound healing.

Effects of directional adaptation on selenium tolerance and accumulation of heterotrophic Chlorella pyrenoidosa / 生物工程学报

Selenium (Se) is an essential trace element for organisms. Se deficiency will cause diseases such as Keshan disease and Kashin-Beck in human being, and huge loss to animal husbandry. Currently available Se supplements have such problems as low Se content, poor bioavailability, and poor safety. Chlorella pyrenoidosa can produce bioavailable and safe organic Se under suitable conditions, which is thus a promising Se supplement. Therefore, in this study, we tried to improve the Se tolerance and accumulation of C. pyrenoidosa by directional adaptation. To be specific, we gradually increased the concentration of Na2SeO3 in medium to domesticate C. pyrenoidosa and optimized the adapting time and concentration gradient of Na2SeO3 during the adaptation. The results showed that the adapted C. pyrenoidosa was more tolerant to Se and had stronger Se enrichment ability. In 5 L fermenter, the adapted strains could tolerate 40 mg/L Na2SeO3 and the synthesis rate of organic Se was 175.6% higher. Then, Se addition method in the 5 L fermenter was optimized. The result demonstrated that addition of Na2SeO3 at 40 mg/L during heterotrophic culture achieved the final dry weight of C. pyrenoidosa cells at 106.4 g/L, content of organic Se at 1 227 mg/kg, and synthesis rate of organic Se at 1.36 mg/(L·h). Compared with the reported highest cell density of 75 g/L and the highest organic Se content of 560 mg/kg, the corresponding figures in this study were 41.9% and 119.1% higher, respectively. In conclusion, directional adaptation can remarkably improve the Se tolerance and enrichment of C. pyrenoidosa.

Evaluation of the operational conditions in the production and morphology of Chlorella sp / Avaliação das condições operacionais na produção e morfologia de Chlorella sp

Abstract It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% ​​of S for the Chlorella sp.

Resumo Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.

Evaluación del potencial de Desmodesmus asymmetricus y Chlorella vulgaris para la remoción de nitratos y fosfatos de aguas residuales / Potential assessment of Desmodesmus asymmetricus and Chlorella vulgaris for removal of nitrates and phosphates in wastewater

Resumen En este estudio evaluamos las microalgas Chlorella vulgaris y Demodesmus asymmetricus, con el fin de determinar la proporción de microalgas que remueven la mayor concentración de nitrógeno y fósforo en aguas residuales de una planta de tratamiento. Se realizó un diseño de mezclas de las microalgas con el agua residual durante 9 días, con fotoperiodo 12:12 h, en un invernadero. Las mayores eficiencias de remoción de nitrógeno (principalmente NO3 -N y NO2 -N) y fósforo (PO4 ) se observaron en los tratamientos con mayor proporción de D. asymmetricus, entre ellos sobresalió el tratamiento T3 (25% C. vulgaris / 75% D. asymmetricus) donde se removió el 100% de nitrógeno y 77.1% de fósforo. De igual manera con el oxígeno disuelto (OD), el T3 obtuvo el mejor resultado alcanzando una media de 25.50 ± 0.28 mg/L. Finalmente, de acuerdo con el análisis del diseño de mezclas, se determinó que la mezcla óptima de microalgas que logra la mayor producción de OD y la mayor remoción, fue la proporción de 6% de C. vulgaris y 94% de D. asymmetricus en un tiempo de cultivo de 9 días. En conclusión, las microalgas demuestran su capacidad de biorremediación de aguas residuales domésticas.

Abstract In this work, we evaluated the proportion Chlorella vulgaris and Demodesmus asymmetricus microalgae, that removes the highest concentration of nitrogen and phosphorus in wastewater from a treatment plant. A mixture design was employed in this study, for 9 days, with 12:12 h photoperiod, in a greenhouse. The highest nitrogen removal efficiencies (mainly NO3 -N and NO2 -N) and phosphorus (PO4 ) were observed in treatments with the highest proportion of D. asymmetricus, including T3 (25% C. vulgaris / 75 % D. asymmetricus), where 100.0% nitrogen and 77.1% phosphorus were removed. Likewise, T3 obtained the best result of dissolved oxygen (DO), achieving average of 25.50 ± 0.28 mg/L. Finally, according to the analysis of the mixture design, the optimal microalgae mixture was determinated that achieves the highest DO production, and the highest removal was the proportion of 6% of C. vulgaris and 94% of D. asymmetricus in 9 days cultivation time. In conclusion, microalgae have shown their capacity for bioremediation of domestic wastewater, which is an alternative to consider.

Selective activity of diselenides against Aedes aegypti (Diptera: Culicidae) larvae

Abstract INTRODUCTION: Aedes aegypti (L.) is the major vector of arboviruses that causes serious public health concerns in tropical and subtropical countries. METHODS: We examined the larvicidal activity of 1,2-diphenyldiselenide [(PhSe)2] and 1,2-bis(4-chlorophenyl) diselenide [(p-ClPhSe)2] and determine its toxicity to different non-target organisms. RESULTS: (PhSe)2 and (p-ClPhSe)2 killed Ae. aegypti L3 larvae with LC50/24h values of 65.63 µM (20.48 mg/L) and 355.19 µM (135.33 mg/L), respectively. (PhSe)2 was not toxic to the four model organisms. CONCLUSIONS: (PhSe)2 is a larvicidal compound with selective action against Ae. aegypti larvae. The mechanisms of action of (PhSe)2 under field conditions remain to be investigated.

Extracción y evaluación de compuestos antivirales de Chondracanthus chamissoi y Chlorella peruviana contra el virus dengue serotipo 2 / Extraction and antiviral activity assessment of compounds from Chondracanthus chamissoi and Chlorella peruviana against serotype 2 dengue virus

RESUMEN Objetivo: extraer y evaluar la actividad antiviral de los compuestos de Chondracanthus chamissoi y Chlorella peruviana contra DENV-2 en células Vero-76. Materiales y métodos: se extrajeron el carragenano de Chondracanthus chamissoi, los carbohidratos solubles de Chondracanthus chamissoi y Chlorella peruviana y se realizó la prueba de toxicidad en células VERO-76 y la evaluación de la actividad antiviral. Resultados: se obtuvieron carragenanos de la fase de esporofito y gametofito de Chondracanthus chamissoi, los mismos que fueron identificados, mediante infrarrojo, como k-carragenano. Por cromatografía se identificaron nueve azúcares (ribosa, xilosa, arabinosa, fructuosa, manosa, galactosa, sucrosa, maltosa y lactosa) en la muestra de carbohidratos solubles de Chondracanthus chamissoi fase gametofito y cuatro azucares (glucosa, sucrosa, maltosa y lactosa) en la de Chlorella peruviana. Los compuestos de Chondracanthus chamissoi y la solución de carbohidratos solubles de Chlorella peruviana no presentaron efecto citotóxico; los carbohidratos del extracto crudo de Chlorella peruviana sí los tuvieron. Todas las fracciones del extracto crudo de Chondracanthus chamissoi fase gametofítica fueron positivas por la prueba de reducción del número de placas(50) a la dilución 1:5. El k-carragenano de Chondracanthus chamissoi en ambas fases y los extractos crudos de carbohidratos solubles de Chondracanthus chamissoi, Chlorella peruviana y la solución de carbohidratos solubles de Chlorella peruviana inhibieron el crecimiento del virus dengue, pero no los carbohidratos del extracto crudo de la Chlorella peruviana. Conclusiones: los compuestos obtenidos de Chondracanthus chamissoi y Chlorella peruviana presentan actividad antiviral contra DENV-2 por lo cual es necesario continuar los estudios del potencial antiviral de estos compuestos fraccionados y purificados.

ABSTRACT Objective: to extract and determine the antiviral activity of compounds from Chondracanthus chamissoi and Chlorella peruviana against DENV-2 in Vero-76 cells. Materials and methods: carrageenan from Chondracanthus chamissoi and soluble carbohydrates from Chlorella peruviana were extracted, and toxicity tests in VERO-76 cells and antiviral activity were determined. Results: carrageenan from Chondracanthus chamissoi sporophyte and gametophyte phases were obtained, the compound was identified as k-carrageenan using infrared light. Nine sugars (ribose, xylose, arabinose, fructose, mannose, galactose, sucrose, maltose, and lactose) were identified using chromatography in the soluble carbohydrate mix from Chondracanthus chamissoi, and four sugars (glucose, sucrose, maltose, and lactose) from Chlorella peruviana were identified. Compounds from Chondracanthus chamissoi and Chlorella peruviana soluble carbohydrate solutions did not show any cytotoxic effect, carbohydrates from the raw extract from Chlorella peruviana did have this effect. All fractions from the raw extract from the gametophyte phase from Chondracanthus chamissoi were positive in the plate reduction test at 1:5 dilution. K-carrageenan from Chondracanthus chamissoi in both phases, as well as the crude extracts of soluble carbohydrates from Chondracanthus chamissoi and Chlorella peruviana as well as the soluble carbohydrate solution from Chlorella peruviana inhibited growth of dengue virus, but that was not the case with the carbohydrates of the raw extract from Chlorella peruviana. Conclusions: compounds obtained from Chondracanthus chamissoi and Chlorella peruviana show antiviral activity against DENV-2, so it is necessary to continue studies aiming to determine the antiviral potential of these fractioned and purified compounds.

High efficient assimilation of NO₃⁻-N with coproduction of microalgal proteins by Chlorella pyrenoidosa / 生物工程学报

The aim of this study was to establish a novel technology using microalgae for NO₃⁻ removal from high concentration wastewater and conversion to algal proteins. The effects of cultivation modes and illumination modes on the biomass yield, NO₃⁻ assimilation rate and algal protein yield were first investigated in shaking flasks for mixotrophic cultivation of Chlorella pyrenoidosa, and subsequently the scale-up verification in 5-L photo fermenter was successfully conducted. Fed-batch cultivation without medium recycling was the best cultivation mode in shaking flask system, in which the highest biomass yield (35.95 g/L), the average NO₃⁻ assimilation rate (2.06 g/(L·d)) and algal protein content (up to 42.44% of dry weight) were achieved. By using a staged increase of light intensity as illumination modes, the specific growth rate of cells could be significantly promoted to the highest (0.65 d⁻¹). After a 128-hour continuous cultivation in a 5-L photo fermenter, the highest biomass yield and the average NO₃⁻ assimilation rate were reached to 66.22 g/L and 4.38 g/(L·d) respectively, with the highest algal protein content at 47.13% of dry weight. Our study could provide a photo fermentation technology of microalgae for highly efficient treatment of waste industrial nitric acid and/or high concentration nitrate wastewater. This microalgae-based bioconversion process could coproduce protein-rich microalgal biomass, which facilitates the resource utilization of these type wastewater by trash-to-treasure conversion.

Effect of the Application of Chlorella Vulgaris Ointment to the Number of Fibroblast Cells as an Indicator of Wound Healing in the Soft Tissue of Pig Ears

Abstract Objective: To analyze the clinical and histological condition of Chlorella vulgaris ointment extract smearing on wound healing. Material and Methods: The sample consisted of 9 pigs by making 4 incisions on the pig's right ear measuring 2cm x 1cm and applying Chlorella vulgaris ointment in 3 concentrations namely 5%, 10%, 15% and without ointment application as the control group. Furthermore, the observation of the clinical condition of wounds divided into 4 time periods (day 1, 3, 7 and 14). After completing clinical observations based on time period, the skin of the pig's ear was taken by cutting in the area that had been made injured. Skin tissue extraction carried out under inhalation and local anesthesia. The tissue pieces are then processed in the anatomical pathology laboratory to become 36 slide preparations. The clinical trial assessment was done using parameters of wound moisture, color of wound and scab wound. Whereas for histological examination was done by looking at the number of fibroblast cells in the CX31 light microscope with 40x magnification. ANOVA and Kruskal Wallis tests were used. Results: In the clinical observation conditions there were significant differences between the treatment group and the control group as well as the number of fibroblast cells there were significant differences between the 3 concentrations of Chlorella vulgaris extract ointment and the per time period control group. Conclusion: Chlorella vulgaris extract ointment containing 15% extract gives the best results in accelerating the wound healing process in the pig's ear seen from wound healing and increased number of fibroblast cells.

Chlorella sorokiniana and Chlorella minutissima exhibit antioxidant potentials, inhibit cholinesterases and modulate disaggregation of ß-amyloid fibrils

BACKGROUND: Microalgae are aquatic chlorophyll-containing organisms comprising unicellular microscopic forms, and their biomasses are potential sources of bioactive compounds, biofuels and food-based products. However, the neuroprotective effects of microalgal biomass have not been fully explored. In this study, biomass from two Chlorella species was characterized, and their antioxidant, anticholinesterase and anti-amyloidogenic activities were investigated. RESULTS: GC­MS analysis of the extracts revealed the presence of some phenols, sterols, steroids, fatty acids and terpenes. Ethanol extract of Chlorella sorokiniana (14.21 mg GAE/g) and dichloromethane extract of Chlorella minutissima (20.65 mg QE/g) had the highest total phenol and flavonoid contents, respectively. All the extracts scavenged 2,2-diphenyl-1-picrylhydrazyl, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) and hydroxyl radicals. The highest metal chelating activity of the extracts was observed in the ethanol extracts of C. minutissima (102.60 µg/mL) and C. sorokiniana (107.84 µg/mL). Furthermore, the cholinesterase inhibitory activities of the extracts showed that ethanol extract of C. sorokiniana (13.34 µg/mL) exhibited the highest acetylcholinesterase inhibitory activity, while dichloromethane extract of C. minutissima (11.78 µg/mL) showed the highest butyrylcholinesterase inhibitory activity. Incubation of the ß-amyloid protein increased the aggregation of amyloid fibrils after 96 h. However, ethanol extract of C. sorokiniana and C. minutissima inhibited further aggregation of Aß1­42 and caused disaggregation of matured protein fibrils compared to the control. This study reveals the modulatory effects of C. sorokiniana and C. minutissima extracts on some mediators of Alzheimer's disease and provides insights into their potential benefits as functional food, nutraceutics or therapeutic agent for the management of this neurodegenerative disease.

Study of the changes in the growth, protein, and bioactive profile of Chlorella emersonii KJ725233 in response to sodium and ammonium nitrate

India. The alterations in its chlorophyll, protein, and antioxidant content in response to cationic stress were studied.Chlorella emersonii KJ725233 (CEK) was subjected to NaNO3 and NH4 (NO3)2 at concentrations equivalent to0.9 g/l (1×) and 1.8 g/l (2×) in the cultivation media. Qualitative alterations in the bioactives of the microalgawere identified by gas chromatography–high-resolution mass spectrometry (GC-HRMS), while the protein,chlorophyll, and antioxidant manipulations were spectrophotometrically quantified. Doubling of the proteincontent was observed when CEK was grown in 1× NH4+, whereas in 2× NH4+, chlorosis was significant. 2× NH4+also induced oxidative stress on CEK as evident from the 85.72% ± 6.72%, 197.47% ± 7.01%, 22.24% ± 1.78%,and 187.37% ± 1.88% increase in antioxidant potential, ferric reducing capacity, radical scavenging potential, andtotal phenolic content, respectively, as compsared to CEK grown in 1× Na+. These alterations as indicated fromthe GC-HRMS data correlate to the bioactive inductions/variations of/in Vitamin E, phytol, and its isomer in CEKgrown in 2× NH4+. The study thus indicates that manipulations of nitrate salts in the media significantly induce, aswell as alter the concentrations of commercially significant compounds like Vitamin E, phytol, etc.

Effects of Sun and Oven Drying Techniques on Quality of Oil Produced from Chlorella vulgaris (Microalgae) Biomass

This study involved the molecular identification of Chlorella vulgaris microalgae obtained from Kaduna State University Fish Pond for biodiesel production potential. The DNA of Chlorella microalgae was extracted and subjected to PCR. The molecular weight of the PCR product obtained was 1.8kb using 18S rDNA primer sets and BLAST analyses revealed 95% identity with Chlorella vulgaris. The Chlorella vulgaris was cultured in open aquaria tanks at the Department of Biological Sciences, Nigerian Defence Academy. The biomass harvested was subjected to varying timings of sun and oven drying techniques (25-35ºC for 72hours and 60ºC for 12hours respectively) before extraction of oil from the biomass using solvent extraction method. The values for the density (0.854 and 0.867 cm3), specific gravity (0.875 and 0.876), acid value (0.414 and 0.384 mgKOH/g), saponification value (173.3 and 170.1 mgKOH/g), kinematic viscosity (5.200 and 3.870 mm2/g at 40ºC), flash point (114 and 115ºC) and cetane number (54.00 and 47.70) for the sun and oven dried biomass oil respectively were found to be in accordance with the ASTM standard values for biodiesel and fossil diesel. GC-MS analyses of the oil extracted using the two drying methods showed that the fatty acid profiling of the oil obtained from sun dried processed biomass had C14:0, C15:0, C16:0, C18:0, C18:1 cis9 and C22:1ω9 while the oven dried biomass oil had C14:0, C16:0, C19:0, C11:1, C18:1 cis9 and C22:1ω9. Drying methods, therefore, had influenced on the composition of saturated and unsaturated fatty acids. The oven dried biomass oil possesses high monounsaturated fatty acids when compared to sun dried biomass oil though the most important fatty acids (C14:0, C16:0 and C18:1) found in standard biodiesel were present in both. The results suggested that Chlorella vulgaris microalgae can be sustainably harvested for the production of biodiesel, both drying techniques can be employed for effective extraction but oven dried biomass oil was found to be of high quality because of the balanced in saturated and unsaturated fatty acid compositions and have an easy mode of operation but it required instrumentation.

Effects of aerobic exercise combined with chlorella pyrenoidos of disintegrated cell wall on some indicators of lipid metabolism in rats with high-fat diet / 中国应用生理学杂志

OBJECTIVE@#To study the effects of aerobic exercise combined with chlorella pyrenoidos of disintegrated cell wall on the lipid metabolism in rats with high-fat diet.@*METHODS@#Fifty-five male Wistar rats were subjected to adaptive feeding for 4 days and weight-free swimming training for 3 days, 20 min/d. After eliminating 5 rats that were not suitable for swimming training, the other rats were randomly divided into 5 groups according to their body weight:control group (C group), high fat diet group (H group), high-fat diet + chlorella group(HC group), high fat diet + aerobic exercise group (HM group), high fat diet + chlorella + aerobic exercise group (HMC group), 10 in each group. The HM and HMC group were subjected to 60 min/d swimming training for 6 weeks with non-weight-bearing. Group C were fed regular diet. The other groups were fed with high-fat diet, the rats in group HC and HMC were intragastrically treated with chlorella pyrenoidos of disintegrated cell wall at the dose of 3.9 g/(kg·d), the volume was 5 ml/kg, and the other groups are given equivalent saline. The Lee's index and biochemical indexes of blood and liver were measured after 6 weeks.@*RESULTS@#Compared with group C, Lee's index, serum levels of free fatty acids(FFA), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-c), liver FFA and interleukin-10 (IL-10) were increased significantly (<0.01), the serum level of high-density lipoprotein cholesterol (HDL-c) was decreased significantly (<0.01) in group H. Compared with group H, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05 or <0.01), serum level of HDL-c was increased significantly (<0.05 or <0.01) in group HC, HM and HMC. Compared with group HC and HM, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05), serum level of HDL-c was increased significantly (<0.05) in group HMC.@*CONCLUSIONS@#Aerobic exercise and chlorella pyrenoidos of disintegrated cell wall can improve lipid metabolism in rats with high-fat diet and reduce the lipid toxicity caused by obesity. Joint intervention is more effective than single intervention.

Post-treatment of palm oil mill effluent (POME) using freshwater green microalgae145-

@#Aims:The effectiveness of microalgae in the post-treatment of palm oil mill effluent (POME) was being investigated for colourremoval and COD reduction. Methodology and results:Raw POME, obtained from a local palm oil mill and treated with anaerobic and aerobic processes for 50 days and 16 days of hydraulic retention time (HRT) respectively, was then used in the phycoremediation study. Three different species of microalgae (Ankistrodesmus falcatus, Scenedesmus sp. and Chlorellasp.) were inoculated in a culture media which contained 20%, 40% and 60% dilution of POME. The pH of thetreated POME sample was not adjusted and fixed at the original pH of about pH 8-9. The growth of the microalgae was determined every 2 days based on their chlorophyll concentration. Chlorellasp. showed the best adaptation and grew well in all dilutions of the treated POME sample and subsequently chosen for remediation of the POME sample without any dilution.Conclusion, significance and impact of study:Chemical oxygen demand (COD) and colour removal of POME were determined every 2 days. Chlorellasp. performed well with COD reduction and colour removal of 67.87% and 53.26%, respectively.

Effect of Chlorella pyrenoidosa on Influenza Virus Infected Mice / 日本補完代替医療学会誌

We orally administered Chlorella pyrenoidosa to mice 1 week before infection with the influenza virus up to 14 days after infection, and investigated its effects on mice with the viral infection. The survival rate was determined using the Kaplan-Meier cumulative survival curve, and the distilled water- and Chlorella-administered groups were assessed using the log-rank test. The duration of survival of the Chlorella-administered group was significantly extended (P=0.0394), and Chlorella showed high efficacy against influenza infection.

Hematological and biochemical responses of pirarucu (Arapaima gigas, Arapaimidae) fed with diets containing a glucomannan product derived from yeast and algae / Respostas hematológicas e bioquímicas de pirarucu (Arapaima gigas, Arapaimidae) alimentado com dietas contendo mananoligossacarídeos derivados de leveduras e algas

ABSTRACT The hematological and biochemical responses of pirarucu fingerlings (Arapaima gigas) fed with diets containing different concentrations of a glucomannan product derived from yeast and algae were evaluated in order to ascertain the effect of these diets on fish physiology. Four treatments were conducted, with three replications, with 12 fish in each tank. The product evaluated (MycosorbA+(r)) was incorporated into the commercial diet, at four concentrations: 0, 1, 2 and 4 g.kg-1, called M0%, M0.1%, M0.2% and M0.4%, respectively. After 45 days of feeding, blood samples from six fish in each replicate were collected to perform the analyses. Their weight and length were determined to calculate the condition factor and weight gain, but no differences (P > 0.05) were observed among the treatments. No changes to the hematocrit, hemoglobin or erythrocyte levels or to the hematimetric indices of the pirarucus were observed. The glucose and triglyceride levels of the pirarucus in the M0.1% and M0.2% groups were significantly lower than those of the M0% group. The M0.2% group showed higher albumin levels (P < 0.05) than M0% and M0.4%. The M0.4% group showed a total cholesterol level that was significantly higher than in all other treatments. MycosorbA+(r) contributed towards increasing the levels of defense cells in A. gigas. It would be possible to use this product at concentrations of between 0.1% and 0.2%, given that they increase the levels of some defense cells and plasma albumin concentrations, without changes to hematological parameters, cholesterol and triglyceride plasma levels or condition factor.

RESUMO As características hematológicas e bioquímicas de alevinos de pirarucu Arapaima gigas alimentados com diferentes concentrações de mananoligossacarídeos derivados de leveduras e algas na dieta foram avaliadas para verificar o efeito sobre sua fisiologia. Quatro tratamentos foram conduzidos com três repetições (12 peixes em cada). O produto avaliado (MycosorbA+(r)) foi incorporado à ração comercial, em quatro níveis: 0, 1, 2 e 4 g kg-1 de ração, denominados M0%, M0,1%, M0,2% e M0,4%, respectivamente. Após 45 dias de alimentação, amostras de sangue de seis peixes de cada repetição foram coletadas para realização das análises. O peso e comprimento foram obtidos para cálculo do fator de condição e ganho de peso, entretanto, não foram observadas diferenças (P>0,05) entre os tratamentos. Assim como não foram observadas alterações nos valores de hematócrito, hemoglobina, eritrócitos e índices hematimétricos dos pirarucus. A concentração de glicose e triglicérides dos pirarucus dos grupos M0,1% e M0,2% foram significativamente menores que o tratamento M0%. Os peixes do tratamento M0,2% apresentaram níveis de albumina maior (P<0,05) que do M0% e M0,4%. Os peixes alimentados com M0,4% mostraram nível de colesterol total significativamente maior que todos os demais tratamentos. MycosorbA+(r) contribuiu para o aumento das células de defesa de A. gigas, podendo ser utilizado nas concentrações de 0,1% a 0,2%, devido ao aumento do número de certas células de defesa e dos níveis plasmáticos de albumina e por não ter sido observadas outras alterações nos parâmetros hematológicos, nos níveis plasmáticos de colesterol e triglicérides e no fator de condição.

Changes of the Total Lipid and Omega-3 Fatty Acid Contents in two Microalgae Dunaliella Salina and Chlorella Vulgaris Under Salt Stress

ABSTRACT Effect of salt stress on biomass, cell number, contents of total lipid, omega-3 fatty acids, including ALA (Alpha Linolenic Acid), EPA (Eicosapentaenoic Acid) and DHA (Docosahexaenoic Acid) and their biosynthetic pathway intermediates (palmitic acid, stearic acid, oleic acid and linoleic acid) of two microalgae Dunaliella salina and Chlorella vulgaris were investigated. Dilution stress from 1.5 to 0.5 M NaCl and salt stress from 1.5 to 3 M NaCl were incorporated into the D. salina medium. Salt stress of 200 mM NaCl was also applied to C. vulgaris culture. Results indicated that increasing salt concentration resulted in the reduced growth rate of C. vulgaris and substantial increase of the total lipid content in both species. Proper growth rate of D. salina observed at 1.5 M of NaCl, but higher and lower concentrations led to the decreased growth rate of D. salina. In addition, considerable increase in the degree of fatty acid unsaturation and thereby the total omega 3 fatty acid content of D. salina was observed under salt stress. Salt stress had little positive effect on the amount of total omega-3 fatty acid of C. vulgaris due to the slight increase of the EPA content. Results showed that salt stress is an effective way for enhancing the total lipid and omega-3 fatty acid production in D. salina.

Evaluation of the operational conditions in the production and morphology of Chlorella sp

Abstract It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% of S for the Chlorella sp.

Resumo Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.

Effect of sodium chloride on growth and lipid accumulation of Chlorella protothecoides CS-41 / 生物工程学报

With basal medium, we studied the growth status, lipid droplet distribution, total lipid content of Chlorella protothecoides CS-41 treated with different concentrations of sodium chloride (0, 150, 300 and 600 mmol/L) by optical microscopy, electron microscopy, confocal laser focusing and Nile red staining. Results show that the addition of NaCl affected the growth of Chlorella protothecoides CS-41. With the increase of NaCl concentration, the growth rate of Chlorella was inhibited. Chlorella cell wall became thicker, and lipid droplets increased. At the early stage, the amount of lipid droplets in the 600 mmol/L NaCl culture was the highest, but at the late-log stage, the amount of lipid droplets increased with the increase of the biomass of culture in 150 and 300 mmol/L NaCl culture. At the stable stage, biomass (dry weight) in 300 mmol/L NaCl culture was 73.55% of that in the control, but the total lipid content was 2.22 times higher than that in the control. A certain concentration of sodium chloride treatment can significantly increase the lipid content of Chlorella protothecoides CS-41.

Bioassay-guided isolation of functional components from hot water extract of Chlorella pyrenoidosa / 生物工程学报

The main functional ingredients of hot water extract of Chlorella pyrenoidosa (CPE) were investigated through a bioassay-guided fractionation based on free radical scavenging and macrophage proliferation effects. The main functional ingredients of CPE were polysaccharides (PS) that were isolated by high pressure extraction, Sevag method, ethanol precipitation and ultrafiltration separation. Crude polysaccharides were further separated and purified by ion exchange chromatography DEAE52 and size exclusion chromatography Sephadex G-100. The purified fractions were analyzed by gel permeation chromatography. Molecular weights of the purified fractions PS-1-4-2, PS-1-3-2 and PS-2-3-3 were 3.97×10⁴, 2.28×10⁴ and 4.1×10³ Da, respectively. Bioassay-guided fractionation results indicated that CPE could remove free radicals and promote Ana-1 cells proliferation, mainly due to its various components working together. The components of free radicals scavenging mainly concentrated in PS-1-3, PS-1-4, PS-2-3 and PS-2-4. The components of Ana-1 proliferation mainly concentrated in PS-1-3, PS-1-4 and PS-2-3. This study established the activity screening method of main functional component from CPE, and got three new functional ingredients. It can be used to guide the development of high value products, further promote the industrialization process of microalgae energy, and realize microalgae 'high value products, microalgae energy and microalgae carbon' integration of exemplary role.