A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock.

Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was to present a preprocessing method of algae oil feedstock (Scenedesmus) to remove chlorophyll by saponification. The results showed that 96% of chlorophyll in biomass was removed. High quality orange transparent oil could be extracted from the chlorophyll reduced biomass. Specifically, the proportion of neutral lipids and saturation levels of fatty acids increased, and the pigments composition became carotenoids-based. The critical parameters of chlorophyll reduced biodiesel conformed to the standards of the USA, China and EU. Sodium copper chlorophyllin could be prepared from the bleaching effluent. The results presented herein offer a useful pathway to improve the quality of microalgae oil and reduce the cost of microalgae biodiesel.

Gelatiniphilus marinus gen. nov., sp. nov., a bacterium from the culture broth of a microalga, Picochlorum sp. 122, and emended description of the genus Hwangdonia.

A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped bacterium, designated strain GYP-24T, was isolated from the culture broth of a marine microalga, Picochlorum sp. 122. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain GYP-24T forms a robust cluster with H.wangdoniaseohaensis KCTC 32177T (95.8 % sequence similarity) in the family Flavobacteriaceae. Growth of strain GYP-24T was observed at 15, 22, 28, 30, 33 and 37 °C (optimal 30-33 °C), pH 6.0-10.0 (optimal pH 7.0-8.0) and in the presence of 0.5-4 % (w/v) NaCl (optimal 2-3 %). The only menaquinone of strain GYP-24T was MK-6, and the G+C content of the genomic DNA was 36.9 mol%. The major fatty acid profile comprised iso-C17 : 0 3-OH, summed feature 3 (C16 : 1 ω7c/ω6c), iso-C15 : 1 G and iso-C15 : 0. The major polar lipids of strain GYP-24T were phosphatidylethanolamine, one unidentified phospholipid, three unidentified aminolipids and three unidentified lipids. Comprehensive analyses based on polyphasic characterization of GYP-24T indicated that it represents a novel species of a new genus, for which the name Gelatiniphilus marinus gen. nov., sp. nov. is proposed. The type strain is GYP-24T (=KCTC 42903T=MCCC 1K01730T). An emended description of the genus Hwangdonia is also given.

Pyruvatibacter mobilis gen. nov., sp. nov., a marine bacterium from the culture broth of Picochlorum sp. 122.

A Gram-stain-negative, aerobic bacterium, designated strain GYP-11T, was isolated from the culture broth of a marine microalga, Picochloruma sp. 122. Cells were dimorphic rods; free living cells were motile by means of a single polar flagellum, and star-shaped-aggregate-forming cells were attached with stalks and non-motile. Sodium pyruvate or Tween 20 was required for growth on marine agar 2216.16S rRNA gene sequence analysis revealed that this isolate shared 94.07 % similarity with its closest type strain, Parvibaculum hydrocarboniclasticum EPR92T. Phylogenetic analyses indicated that strain GYP-11T represents a distinct lineage in a robust clade consisting of strain GYP-11T, alphaproteobacterium GMD21A06 and Candidatus Phaeomarinobacter ectocarpi Ec32. This clade was close to the genera Parvibaculum and Tepidicaulis in the order Rhizobiales. Chemotaxonomic and physiological characteristics, including cellular fatty acids and carbon source profiles, also readily distinguished strain GYP-11T from all established genera and species. Thus, it is concluded that strain GYP-11T represents a novel species of a new genus in the order Rhizobiales, for which the name Pyruvatibacter mobilis gen. nov., sp. nov. is proposed. The type strain of Pyruvatibacter mobilis is GYP-11T ( = CGMCC 1.15125T = KCTC 42509T).

Aliikangiella marina gen. nov., sp. nov., a marine bacterium from the culture broth of Picochlorum sp. 122, and proposal of Kangiellaceae fam. nov. in the order Oceanospirillales.

A Gram-stain-negative, non-motile, non-spore-forming, long rod-shaped bacterium, designated strain GYP-15T, was isolated from the culture broth of a marine microalga, Picochloruma sp. 122. Phylogenetic analyses revealed that strain GYP-15T shared 90.6 % 16S rRNA gene sequence similarity with its closest relative, Kangiella aquimarina KCTC 12183T, and represents a distinct phylogenetic lineage in a robust clade consisting of GYP-15T and members of the genera Kangiella and Pleionea in the order Oceanospirillales. Chemotaxonomic and physiological characteristics, including major cellular fatty acids, NaCl tolerance and pattern of carbon source utilization, could also readily distinguish strain GYP-15T from all established genera and species. Thus, it is concluded that strain GYP-15T represents a novel species of a new genus, for which the name Aliikangiella marina gen. nov., sp. nov. is proposed. The type strain of Aliikangiella marina is GYP-15T ( = MCCC 1K01163T = KCTC 42667T). Based on phylogenetic results, 16S rRNA gene signature nucleotide pattern and some physiological characteristics, the three genera Kangiella, Pleionea and Aliikangiella are proposed to make up a novel family, Kangiellaceae fam. nov., in the order Oceanospirillales.

Wenzhouxiangella marina gen. nov, sp. nov, a marine bacterium from the culture broth of Picochlorum sp. 122, and proposal of Wenzhouxiangellaceae fam. nov. in the order Chromatiales.

A Gram-stain negative, non-motile, non-phototrophic, non-alkaliphilic, obligately aerobic, chemoheterotrophic, and rod-shaped bacterium, designated strain Ma-11(T), was isolated from the culture broth of a marine microalga, Picochloruma sp. 122. Phylogenetic analyses showed that strain Ma-11(T) has less than 91 % similarity to its closest relative, Thioalkalivibrio sulfidiphilus HL-EbGR7(T), represents a distinct phylogenetic lineage in the order Chromatiales, and could not be assigned to any defined families in this order. Chemotaxonomic, genetic and physiological characteristics, including major fatty acids, genomic G+C content, lack of motility, aerophilicity and chemoheterotrophicity, could readily distinguish strain Ma-11(T) from any established members of the order Chromatiales. Based on the 16S rRNA gene sequence analysis and its signature nucleotide pattern, a new family Wenzhouxiangellaceae fam. nov. comprising the genus Wenzhouxiangella gen. nov. and species Wenzhouxiangella marina sp. nov. is proposed. The type strain is Ma-11(T) (=CGMCC 1.14936(T) = KCTC 42284(T) = MCCC 1K00261(T)).

Physicochemical and crystalline properties of heat-moisture-treated rice starch: combined effects of moisture and duration of heating.

BACKGROUND: Currently there is much interest in the application of physical modification techniques such as heat-moisture treatment (HMT). The effects of HMT on normal and waxy rice starches, subject to different levels of moisture content and duration of heating, were investigated. RESULTS: Water solubility index (determined at 90 °C) decreased after HMT for normal and waxy rice starches, while swelling power (determined at 90 °C) showed inconsistent results (decrease for normal type, increase for waxy type) after HMT. Values in pasting parameters of normal and waxy rice starch increased initially, but the extent of increase slowed down with moisture content and length of treatment increasing. HMT decreased gelatinization temperatures with 4 h and 8 h treatment, but when length of treatment was prolonged to 16 h gelatinization temperature increased. Degree of crystallinity decreased for all treatments, and decreased much more at higher levels of moisture content. CONCLUSION: Variations in levels of moisture content and duration of heating had significant effects on physicochemical and crystalline properties to different extents.

Bacterioplanes sanyensis gen. nov., sp. nov., a PHB-accumulating bacterium isolated from a pool of Spirulina platensis cultivation.

A Gram-negative, poly-3-hydroxybutyrate-accumulating rod bacterium, strain GYP-2(T), was isolated from a pool of marine Spirulina platensis cultivation, Sanya, China. Growth was observed at 10-45 °C and pH 6-10 in the presence of 1-10 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate belonged to Gammaproteobacteria and displayed 93.8-95.3 % 16S rRNA gene sequences similarities to members of the genera Thalassolituus, Oleibacter, and Oceanobacter, but house-keeping gene gyrB (encode DNA gyrase beta subunit) demonstrated that the new isolate was distantly related to Thalassolituus, Oleibacter, and Oceanobacter species (only 77-83 % gene gyrB sequences similarities).The G+C content of genomic DNA was 55 mol%. The major respiratory quinone was Q-9, while that for Oceanobacter kriegii LMG 6238(T) was Q-8. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. On the basis of its physiological, chemotaxonomic, and molecular properties, strain GYP-2(T) is suggested to represent a novel species of a new genus in Gammaproteobacteria, for which the name Bacterioplanes sanyensis gen. nov., sp. nov. is proposed. The type strain is GYP-2(T) (=CGMCC 1.12392(T)=KCTC 32220(T)).

Nonhongiella spirulinensis gen. nov., sp. nov., a bacterium isolated from a cultivation pond of Spirulina platensis in Sanya, China.

A Gram-negative, aerobic, motile rod strain, designated Ma-20(T), was isolated from a pool of marine Spirulina platensis cultivation, Sanya, China, and was subjected to a polyphasic taxonomy study. Strain Ma-20(T) can grow in the presence of 0.5-11 % (w/v) NaCl, 10-43 °C and pH 6-10, and grew optimally at 30 °C, pH 7.5-9.0 in natural seawater medium. The polar lipids were composed of phosphatidylethanolamine, three unidentified phospholipids and three unidentified polar lipids. The respiratory quinone was ubiquinone 8 (Q-8) and the major fatty acids were C18:1ω6c/C18:1ω7c (summed feature 8, 32.84 %), C16:1ω6c/C16:1ω7c (summed feature 3, 30.76 %), C16:0 (13.54 %), C12:03-OH (4.63 %), and C12:0 (4.09 %). The DNA G+C content of strain Ma-20(T) was 58 mol %. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Ma-20(T) belonging to Gammaproteobacteria, it shared 88.46-91.55 and 89.21-91.26 % 16S rRNA gene sequence similarity to the type strains in genus Hahella and Marinobacter, respectively. In addition to the large 16S rRNA gene sequence difference, Ma-20(T) can also be distinguished from the reference type strains Hahella ganghwensis FR1050(T) and Marinobacter hydrocarbonoclasticus sp. 17(T) by several phenotypic characteristics and chemotaxonomic properties. On the basis of phenotypic, chemotaxonomic and phylogenetic properties, strain Ma-20(T) is suggested to represent a novel species of a new genus in Gammaproteobacteria, for which the name Nonhongiella spirulinensis gen. nov., sp. nov. is proposed. The type strain is Ma-20(T) (=KCTC 32221(T)=LMG 27470(T)).

[Adaptability of oleaginous microalgae Chlorococcum alkaliphilus MC-1 cultivated with flue gas].

In order to lower the cost of lipid production of microalgae and reduce greenhouse gas emissions, microalgae Chlorococcum alkaliphilus MC-1 with the characteristics of rapid pH drift and high pH adaptability, was cultivated with bubbling of flue gas. The experiment was first performed in the photobioreactor (15 L) in three groups (control group, CO2 group and flue gas group), then, in the open raceway pond (24 m2). The adaptability of microalgae MC-1 to the cultivation with flue gas was studied. The results showed that the maximum biomass concentration, growth rate, total lipid content and CO2 fixation rate were (1.02+/-0.07) g/L, (0.12+/-0.02) g/(L.d), (37.84+/-0.58)% and (0.20+/-0.02) g/(L.d) in the photobioreactor treated with flue gas, 36%, 33.33%, 15.34% and 33.33% higher than those of the CO2 group, respectively. In the open raceway pond with aeration of flue gas, the maximum biomass concentration, growth rate, total lipid content and CO2 fixation rate were 147.40 g/m2, 14.73 g/(m2.d), 35.72% and 24.01 g/(m2.d), respectively, which were similar to the cultivation with pure CO2. The toxic heavy metal contents (Pb, As, Cd and Cr) in the biomass of MC-1 treated with flue gas were all below the legal limits. Additionally, the absorptive effect of CO2, NO and SO2 were determined. In the photobioreactor and open raceway pond, the average absorption ratios of these gases were all higher than previous studies. Therefore, our study showed that MC-1 can adapt to the cultivation with flue gas, and it is feasible to enlarge the outdoor cultivation of MC-1 for lipid production coupling with emissions reduction of flue gas.