Saline Soil Samples Research Articles

Streptomyces sparsus sp. nov., isolated from a saline and alkaline soil

A salt- and alkali-tolerant actinomycete strain, YIM 90018(T), was isolated from a saline and alkaline soil sample collected from Qinghai, China. Aerial hyphae of strain YIM 90018(T) were only produced on YIM 82 agar. Vegetative hyphae were well developed and did not fragment. Straight or flexuous (rectiflexibiles) spore chains were produced. The isolate grew well with 25 % (w/v) MgCl(2) x 6H(2)O and at pH 10. All of these characters indicated that strain YIM 90018(T) belonged to the genus Streptomyces. On the basis of phylogenetic analysis of the 16S rRNA gene sequence, DNA-DNA hybridization and phenotypic characteristics, strain YIM 90018(T) could be differentiated from all recognized species of the genus Streptomyces. A novel species, Streptomyces sparsus sp. nov., is proposed, with strain YIM 90018(T) ( = CCTCC AA204019(T) = DSM 41858(T)) as the type strain.

Streptohalobacillus salinus gen. nov., sp. nov., a moderately halophilic, Gram-positive, facultative anaerobe isolated from subsurface saline soil

A Gram-stain-positive, rod-shaped, non-sporulating, motile and moderately halophilic bacterium, designated strain H96B60(T), was isolated from a saline soil sample of the Qaidam basin, China. The strain was facultatively anaerobic. Major end products formed from glucose fermentation were acetate, ethanol and lactic acid. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The isoprenoid quinone component was menaquinone-6 (MK-6). The predominant cellular fatty acids were C(16: 0), anteiso-C(13 : 0) and anteiso-C(15 : 0). The genomic DNA G+C content of strain H96B60(T) was 36.2 mol%. Phylogenetic analysis based on comparative 16S rRNA gene sequences indicated that strain H96B60(T) represented a novel phyletic lineage within the family Bacillaceae and was related most closely to Halolactibacillus species (96.1-96.4 % similarity). Based on the phenotypic, chemotaxonomic and phylogenetic data presented, strain H96B60(T) is considered to represent a novel species of a new genus, for which the name Streptohalobacillus salinus gen. nov., sp. nov. is proposed. The type strain of Streptohalobacillus salinus is H96B60(T) ( = DSM 22440(T) = CGMCC 1.7733(T)).

A Spectral Index for Estimating Soil Salinity in the Yellow River Delta Region of China Using EO-1 Hyperion Data

Soil salinization is one of the most common land degradation processes. In this study, spectral measurements of saline soil samples collected from the Yellow River Delta region of China were conducted in laboratory and hyperspectral data were acquired from an EO-1 Hyperion sensor to quantitatively map soil salinity in the region. A soil salinity spectral index (SSI) was constructed from continuum-removed reflectance (CR-reflectance) at 2 052 and 2 203 nm, to analyze the spectral absorption features of the salt-affected soils. There existed a strong correlation ( r =0.91) between the SSI and soil salt content (SSC). Then, a model for estimation of SSC with SSI was established using univariate regression and validation of the model yielded a root mean square error (RMSE) of 0.986 and an R 2 of 0.873. The model was applied to a Hyperion reflectance image on a pixel-by-pixel basis and the resulting quantitative salinity map was validated successfully with RMSE = 1.921 and R 2 =0.627. These suggested that the satellite hyperspectral data had the potential for predicting SSC in a large area.

Zhihengliuella alba sp. nov., and emended description of the genus Zhihengliuella

A Gram-positive, non-motile, white-pigmented, short rod actinobacterium, designated YIM 90734T, was isolated from a saline soil sample collected from Ganjiahu Suosuo Forest National Nature Reserve in Xinjiang province, north-west China, and its taxonomic position was investigated by using a polyphasic approach. Strain YIM 90734T grew optimally at 28-37 degrees C and pH 6.0-8.0 and in 5% (w/v) NaCl. The peptidoglycan type was A4alpha, L-Lys-L-Ala-L-Glu and tyvelose and mannose were the major cell-wall sugars. The predominant menaquinones were MK-10 and MK-9. Major cellular fatty acids (>10% of total) were anteiso-C15:0 and anteiso-C17:0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown phospholipid and two unknown glycolipids. The DNA G+C content was 70.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 90734T belonged to the genus Zhihengliuella. The 16S rRNA gene sequence similarity between strain YIM 90734T and the type strain of the only recognized Zhihengliuella species, Zhihengliuella halotolerans, was 97.7%. However, the level of DNA-DNA relatedness of the two strains was 41.4%. The DNA-DNA relatedness data and differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain YIM 90734T could be differentiated from Z. halotolerans. On the basis of the data presented, strain YIM 90734T is considered to represent a novel species of the genus Zhihengliuella, for which the name Zhihengliuella alba sp. nov. is proposed. The type strain is YIM 90734T (=KCTC 19375T=DSM 21143T). The description of the genus Zhihengliuella has also been emended.

Kocuria halotolerans sp. nov., an actinobacterium isolated from a saline soil in China

A Gram-positive actinobacterium, designated strain YIM 90716(T), was isolated from a saline soil sample collected from Ganjiahu Suosuo Forest National Nature Reserve in Xinjiang Province, north-west China. The new isolate contained lysine, glutamic acid and alanine with peptidoglycan type Lys-Ala(3) (variation A3alpha). The major phospholipids were phosphatidylglycerol and diphosphatidylglycerol. The predominant menaqinone was MK-7(H(2)). The major fatty acids were anteiso-C(15 : 0), iso-C(16 : 0) and anteiso-C(17 : 0). The DNA G+C content of strain YIM 90716(T) was 68.0 mol%. Chemotaxonomic properties supported the affiliation of strain YIM 90716(T) to the genus Kocuria. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the organism was related most closely to Kocuria kristinae DSM 20032(T) (96.8 % similarity) and showed lower levels of 16S rRNA gene similarity (<96.5 %) with the type strains of other species of the genus Kocuria. The results of fatty acid analysis and physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain YIM 90716(T) from its closest relatives. On the basis of data from the present polyphasic study, strain YIM 90716(T) is considered to represent a novel species of the genus Kocuria, for which the name Kocuria halotolerans sp. nov. is proposed. The type strain is YIM 90716(T) (=DSM 18442(T)=KCTC 19172(T)=CCTCC AB 206069(T)).

The Effect of Air Entry Values on Hysteresis of Water Retention Curve in Saline Soil

Problem statement: The saline soil in Northeast Thailand is caused by saline groundwater rise in unsaturated zone to accumulate as salt at soil surface. Approach: This problem had been exacerbated in the last few decades by human activities e.g., deforestation and salt mining. This salinity problem can be solved by capillary rise control of saline groundwater flow. Results: The soil water retention curve formulation was essential for the control procedure design. In this study, the soil water retention curves of saline soil samples were derived by the hanging column and pressure plate apparatus techniques. The hysteresis of the curves together with air and water entry values were scrutinized from the primary wetting and drying retention curves. Conclusion: The experimental results showed that the degree of hysteresis varies with the air entry value of the soil. The new finding can be very useful in modeling for salinity control.

Nesterenkonia halophila sp. nov., a moderately halophilic, alkalitolerant actinobacterium isolated from a saline soil

A Gram-positive, non-motile, moderately halophilic, alkalitolerant actinobacterium, designated strain YIM 70179(T), was isolated from a saline soil sample collected from Xinjiang Province, north-west China, and was subjected to a polyphasic taxonomic study. The cell-wall peptidoglycan type of strain YIM 70179(T) was A4alpha, l-Lys-Gly-l-Glu. Cells of the isolate contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unknown glycolipid, MK-8 as major menaquinone and anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(16 : 0) as major fatty acids. The DNA G+C content was 68.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 70179(T) fell within the radiation of species of the genus Nesterenkonia. Levels of 16S rRNA gene sequence similarity between strain YIM 70179(T) and the type strains of recognized Nesterenkonia species were below 97 %, except to Nesterenkonia halobia DSM 20541(T) (99.6 %), but these two strains exhibited a low level of DNA-DNA relatedness (18.4 %). Based on genetic and phenotypic evidence, it is proposed that strain YIM 70179(T) represents a novel species of the genus Nesterenkonia, for which the name Nesterenkonia halophila sp. nov. is proposed. The type strain is YIM 70179(T) (=DSM 16378(T) =KCTC 19048(T)).

Salinicoccus salitudinis sp. nov., a new moderately halophilic bacterium isolated from a saline soil sample

A novel pale-yellow-pigmented, moderately halophilic, facultatively alkaliphilic, non-motile, non-spore-forming, catalase- and oxidase-positive, obligately aerobic Gram-positive coccus, strain YIM-C678T was isolated from a saline soil sample collected from a hypersaline habitat in the Qaidam basin, northwest China. The organism grew at 4-37 degrees C and pH 6.0-11.0, with optimum growth at 25 degrees C and pH 8.0. Strain YIM-C678T grew optimally in the presence of 10-12% (w/v) NaCl and growth was observed in 1-25% (w/v) NaCl. The cell wall murein type was L: -Lys-Gly5. Major cellular fatty acids were anteiso-C15:0, iso-C15:0, iso-C16:0 and C16:0. Menaquinone 6 (MK-6) was the major respiratory quinone. The DNA G + C content was 46.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain YIM-C678T belonged to the family Staphylococcaceae and was most closely related to the eight described species of the genus Salinicoccus with sequence similarities from 92.2 (S. luteus YIM 70202T) to 97.5% (S. kunmingensis YIM Y15T). The DNA-DNA relatedness between strain YIM-C678T and S. kunmingensis YIM Y15T was 35.4%. Chemotaxonomic data and 16S rRNA gene sequence analysis supported the affiliation of strain YIM-C678T with the genus Salinicoccus. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic differences and DNA-DNA hybridization data supported the view that the bacterium represents a novel species of the genus Salinicoccus, for which the name Salinicoccus salitudinis sp. nov. is proposed, with YIM-C678T (=DSM 17846 = CGMCC 1.6299) as the type strain.

Zhihengliuella halotolerans gen. nov., sp. nov., a novel member of the family Micrococcaceae

The actinobacterial strain YIM 70185(T) was isolated from a saline soil sample collected from Qinghai province, north-west China, and subjected to a taxonomic investigation. Phylogenetic analysis based on 16S rRNA gene sequences revealed 93.5-96.4 % similarity to members of related genera in the family Micrococcaceae. In the phylogenetic dendrogram based on 16S rRNA gene sequence analysis, strain YIM 70185(T) formed a separate clade next to the genera Micrococcus and Citricoccus within the family Micrococcaceae. The peptidoglycan type was A4alpha, l-lys-l-ala-l-Glu. Cell-wall sugars contained glucose and tyvelose. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and an unknown glycolipid. The menaquinones were MK-9, MK-10 and MK-8 (molar ratio 5 : 2 : 1). The major fatty acids were ai-C(15 : 0) and i-C(15 : 0) and the DNA G+C content was 66.5 mol%. These chemotaxonomic profiles supported the assignment of strain YIM 70185(T) to a novel genus within the family Micrococcaceae. The name Zhihengliuella halotolerans gen. nov., sp. nov. is proposed. The type strain of Zhihengliuella halotolerans is YIM 70185(T) (=DSM 17364(T)=KCTC 19085(T)).

Measurement of terrestrial radiation for assessment of gamma dose from cultivated and barren saline soils of Faisalabad in Pakistan

Natural radioactivity originates from extraterrestrial sources as well as from primordial radioactive elements in the earth crust. The amount of radioactivity in soil varies widely and is a source of continuous exposure of human beings to terrestrial radioactivity that depends upon the type of soil and its uses. For the investigation of radioactivity in barren and cultivated soil, an area of about 80 ha of saline soil was selected in Pakka Anna near the city of Faisalabad in the Punjab province of Pakistan. Activity concentration levels due to 40K, 137Cs, 226Ra and 232Th were measured with HPGe detector in 250 saline soil samples collected at a spacing of about 8 ha at a depth of 0–25 cm with intervals of 5 cm depth. Activity concentration ranges of the concerned radionuclides for both of the soils were as follows: 40K, for barren and cultivated saline soil was 499–604 and 563– 629 Bq kg - 1 , respectively; 137Cs, 3.57–3.63 and 1.98– 5.15 Bq kg - 1 ; 226Ra, 24–29 and 27– 33 Bq kg - 1 , and 232Th, 49–54 and 46– 62 Bq kg - 1 . Gamma dose was estimated using the activity to dose rate conversion factors. The measured activity concentrations and the estimated radiation dose were found to be lying within the range specified in the 2000 report of UNSCEAR. Chemical analysis for Na, Ca and Mg was also carried out along with the measurement of electrical conductivity and pH of soil samples.

Natural environmental radioactivity and estimation of radiation exposure from saline soils

The study was conducted for the investigation of amount of radioactivity in the barren and cultivated soil of Bio saline Research Station in Pakka Anna, established by Nuclear Institute for Agriculture and Biology (NIAB) in 1990, 34 km. away from the city of Faisalabad, in the Punjab province of Pakistan. The studies were done on an area of about 100 hectares of two types of virgin and fertilized saline soils. The technique of gamma ray spectrometry was applied using HPGe (high purity germanium) gamma ray detector and a PC based MCA. Activity concentration levels due to 40 K, 137 Cs, 226 Ra and 232 Th were measured in 250 saline soil samples collected at a spacing of about 4 hectares at the depth level of 0–25 cm. with a step of 5 cm. depth. Activity concentrations ranges of the concerned radionuclides for both of the soils were as follows: 40 K, for virgin and cultivated saline soil was 500−610.2 and Bq/kg 560.2−635.6 respectively; 137 Cs, 3.57−3.63 and 1.98−5.15 Bq/kg 238 U, 26.3−31.6 and 30.3−38.7 Bq/kg, and 232 Th, 50.6−55.3 and 50.6−64.0 Bq/kg respectively. The absorbed dose rate in air lies in the region 63-73 nGyh -1 and 68-83 nGyh -1 for virgin and fertilized soils respectively. This indicates that this region lies in the area of higher radiation background, while comparing with the worlds’ average. The slightly higher value of dose in the fertilized farm may be due to the use of fertilizers for cultivation. Before the radiometric measurements, chemical analysis for concentration of Na, Ca and Mg was also carried out along with the measurement of electrical conductivity and pH of the soil samples.

Isoptericola halotolerans sp. nov., a novel actinobacterium isolated from saline soil from Qinghai Province, north-west China

A Gram-positive, non-motile actinobacterium, designated strain YIM 70177(T), was isolated from a saline soil sample from Qinghai Province, north-west China. Phylogenetic analysis of this organism based on 16S rRNA gene sequences revealed 98.3% similarity to Isoptericola variabilis DSM 10177(T). Chemotaxonomic data determined for the isolate, such as the peptidoglycan type A4alpha, variation L-Lys-D-Asp, supported the placement of strain YIM 70177(T) within the genus Isoptericola. Galactose was detected as cell wall sugar. Phospholipids identified were phosphatidylinositol, phosphatidylglycerol and diphosphatidylglycerol, and the predominant menaquinones were MK-9(H(4)) and MK-9(H(2)). The major fatty acids were ai-C(15:0), C(16:0), ai-C(17:0) and i-C(15:0). The DNA G+C content was 72.8 mol%. The low level of DNA-DNA relatedness (27.4%) to I. variabilis DSM 10177(T) in combination with differentiating chemotaxonomic and physiological data demonstrated that the isolate YIM 70177(T) should be classified as representing a novel species of the genus Isoptericola. The name Isoptericola halotolerans sp. nov. is proposed, with strain YIM 70177(T) (=DSM 16376(T)=KCTC 19046(T)) as the type strain.

Poly(β-hydroxybutyrate) production by a moderate halophile, Halomonas boliviensis LC1

The moderate halophile Halomonas boliviensis, isolated from a Bolivian saline soil sample, was able to accumulate poly(β-hydroxybutyrate) (PHB) when grown under conditions of nutrient limitation and excess carbon source. The concentration of sodium chloride in the medium influenced the cell-growth, -size, and rate of PHB accumulation. Cultivation in shake flasks led to a PHB accumulation of about 54 wt.% with respect to cell dry weight at 4.5% (w/v) NaCl in a medium with butyric acid and sodium acetate as carbon sources. The production of PHB was substantially improved to a maximum value of 88 wt.% during cultivation under controlled conditions of pH and oxygen concentration in a fermentor. The use of glucose and sucrose, respectively, as carbon source could also lead to the production of PHB at an average level of 55 wt.%.

Two new “flagship” ciliates (Protozoa, Ciliophora) from Venezuela: Sleighophrys pustulata and Luporinophrys micelae

Sleighophrys pustulata nov. gen., nov. spec. and Luporinophrys micelae nov. gen., nov. spec. were discovered in a slightly saline mud and soil sample from some flat, dry puddles in the Maracay National Park on the north coast of Venezuela. Their morphology was studied in vivo, in protargol preparations, and in the scanning electron microscope. The new genera are monotypic and belong to the trachelophyllid haptorids. They are characterized by the unique shape of the epicortical scales (lepidosomes). Sleighophrys pustulata, which has a size of about 180×23 μm, possesses type I and unique type V lepidosomes which are hat-shaped and about 7×7 μm in size. Luporinophrys micelae, which has a size of about 200×35 μm, possesses types I, II, and unique type VI lepidosomes which are narrow, about 10 μm high cones composed of fibrous stripes connected by polygonal meshes. The conspicuous body size and the richly structured, comparatively large lepidosomes make S. pustulata and L. micelae biogeographic flagships which may help to cast some light on the pending question whether or not microorganisms have biogeographies. The available data suggest that both species have a restricted geographic distribution, not only because they were not described previously, but mainly because they were absent in about 2000 freshwater samples from central Europe and in about 1000 soil samples collected globally.

Measurement of environmental radioactivity for estimation of radiation exposure from saline soil of Lahore, Pakistan

Radioactivity, natural and man made, is omnipresent in the earth's crust in different amounts. The soil on the earth's crust is a source of continuous exposure to human beings. The amount of radioactivity in soil depends upon the type of soil and its uses. The soil of barren area should show different amount of radioactivity when compared with that of the cultivated soil. For the investigation of amount of radioactivity in the barren soil, an area of about 60 h of saline soil was selected in Rakh Dera Chal near the city of Lahore in the Punjab province of Pakistan. The technique of gamma ray spectrometry was applied using high purity germanium gamma-ray detector and a PC based MCA. Activity concentration levels due to 40 K, 137 Cs, 226 Ra and 232 Th were measured in 125 saline soil samples collected at a spacing of about 4 ha at the depth level of 0– 25 cm with a step of 5 cm depth. Activity concentrations of the concerned radionuclides were as follows: 40 K , 524.84– 601.62 Bq kg −1 , 137 Cs , not detected (less than the lower detection limit), 226 Ra , 24.73– 28.17 Bq kg −1 , and 232 Th , 45.46– 52.61 Bq kg −1 . Before the radiometric measurements, chemical analysis for concentration of Na, Ca and Mg was also carried out along with the measurement of electrical conductivity and Ph of soil samples.

Nocardiopsis xinjiangensis sp. nov., a halophilic actinomycete isolated from a saline soil sample in China.

An actinomycete strain (YIM 90004T) was isolated from a saline soil sample from the Xinjiang Province, People's Republic of China. The strain displayed abundant aerial and substrate mycelia, and short spore chains were borne on the aerial mycelium. The spore chains were composed of non-motile, smooth-surfaced, rod-shaped spores. The cell wall of strain YIM 90004T contained mainly meso-diaminopimelic acid, alanine and glutamic acid (cell wall type III). Glucose, ribose, galactose, xylose and arabinose were the whole-cell sugars of the strain. The predominant phospholipids were phosphatidylinositol and phosphatidylglycerol; MK-10(H2) and MK-10(H4) were the predominant menaquinones. The DNA G + C content of strain YIM 90004T was 74.3 mol%. Chemotaxonomic properties and 16S rDNA analysis placed strain YIM 90004T in the genus Nocardiopsis. On the basis of phenotypic and phylogenetic analyses and DNA-DNA hybridization results, strain YIM 90004T (= CCRC 16285T = CCTCC AA99004T = DSM 44589T) is considered to represent a novel species of the genus Nocardiopsis, for which the name Nocardiopsis xinjiangensis is proposed.

Effect of anion composition of simulated acid rain on nutrient behavior in reclaimed saline soils

The purpose of this study is to demonstrate the relative influence of the anion composition of simulated acid rain on the behavior of nutrients in three reclaimed saline soils. Reclaimed saline soil samples used for this study were collected from surface soils of the Saemangeum and Koheung soils in Korea and the Hachirogata soil in Japan. The Hachirogata soil behaved as a high variable charge soil which was derived from sediments and reclaimed from the deposits of the lake Hachirogata, while the Saemangeum and Koheung soils behaved as permanent charge soils with the cation exchange capacity (CEC) being largely independent of the pH. The simulated acid rain at pH 3.0 was prepared with nitrate-to-sulfate mol ratios of 0.75 : 0.25, 0.5 : 0.5, 0.25 : 0.75, and control (pH 5.7). The influence of the anion composition of simulated acid rain on the changes in the contents of nutrients in reclaimed saline soils was as follows: The soil organic matter content decreased from 36.8 to 24.1 g kg−1 for the Saemangeum soil, from 29.0 to 19.8 g kg−1 for the Koheung soil, and from 137.7 to 85.6 g kg−1 for the Hachirogata soil, respectively: The CEC and point of zero charge (PZC) values in the Saemangeum and Koheung soils were not significantly different, whereas in the Hachirogata soil the CEC decreased by about 15% and the PZC decreased by 1.1 unit. The content of ammonia nitrogen decreased by about 20 to 30%. The content of nitrate nitrogen increased by about 10% for the Hachirogata soil but there was no appreciable difference in the case of the Saemangeum and Koheung soils. The contents of Al-P and Ca-P were not significantly different from the original values in the untreated soil, whereas that of Fe-P decreased by about 30%. The content of inositol phosphate decreased by about 35% in the Hachirogata soil but did not change appreciably in the case of the Saemangeum and Kohueng soils. Different mechanisms were involved in the behavior of anions and cations between the soils with predominant aluminosilicates and the soil rich in hydrous oxides of iron and aluminum. Also, the contents of most of the nutrients changed considerably with the increase of the nitrate content of the simulated acid rain.

Influence of Salinity and Acidity on Bioavailability of Sludge-Borne Heavy Metals. A Case Study of Bangkok Municipal Sludge

This study was conducted to assess the potential of Bangkoksewage sludge for amendment of saline and acidic soil withrespect to heavy metal mobilization. Experiments were carriedout at six levels of salinity (with electrical conductivityvalues of 2, 4, 8, 19, 31 and 42 dS m-1) and two levels ofacidity (with pH values of 5 and 6). A pure sludge sample was used as a control system. Subsamples were collected andanalyzed for total and bioavailable heavy metals. Three sets ofsoil-sludge mixture were prepared using different weight ratio(1:1, 4:1 and 10:1) to simulate the conditions in the field withsludge-amended soil. Samples of soil-sludge mixture were incubated for 4 weeks to stabilize organic substances. Themobility and concentration of bioavailable heavy metal invarying soil-sludge mixture ratio with different electricalconductivity (EC) values were evaluated with the use of DTPA(diethylenetriamine pentaacetric acid) extraction techniques.Pure saline soil sample from Sakhon Nakhon (North-eastern partof Thailand) was used of salt-heavy metal interactions on thegermination percentage in soil mixed with sludge and to screencrops or varieties for their tolerances to soil salinity. Seventypes of seeds – mung bean, corn, soybean, tomato, stringbean, sunflower and marigol – were planted in each of the threesoil-sludge mixtures (1:1, 4:1 and 10:1) with different salinitylevels. Seedlings were monitored by counting the number of seeds thatare germinated and seed germination percentage can be used as anindicator for the level of salinity unsuitable for plant growth.

Apofrontonia lametschwandtneri nov. gen., nov. spec., a new peniculine ciliate (Protozoa, Ciliophora) from Venezuela

Apofrontonia lametschwandtneri was discovered in a highly saline mud and soil sample from a flooded area on the north coast of Venezuela (Maracay National Park). Its morphology was studied in vivo and in silver preparations, as well as in the scanning electron microscope. The new genus Apofrontonia belongs to the family Frontoniidae and is characterized by a combination of three features, viz., a pyriform vestibular opening occupying more than half of the body length; a bowl-shaped vestibulum that posteriorly gradually merges into the cell surface, completely exposing three similarly-structured peniculi; many (>6) vestibular kineties covering the sigmoidal right vestibular wall and not extending beyond the oral cavity. Apofrontonia lametschwandtneri nov. spec. differs from a European congener, A. obtusa (Song and Wilbert 1989) nov. comb. (basionym: Frontonia obtusa Song and Wilbert 1989), by body size (180 m vs. 80 m), number of somatic (155 vs. 90) and vestibular kineties (13 vs. 9), and the number (25 vs. 4–5) and location (scattered vs. lateral) of contractile vacuoles. Considering that A. lametschwandtneri has not been found in Europe, although it is a very large, conspicuous ciliate, it might be endemic to South America.

Production of canthaxanthin by extremely halophilic bacteria

Soil samples from a salt farm were used as a source for the isolation of carotenoid-producing bacteria. The conditions for optimum growth and carotenoid production were established for the isolated bacteria. Carotenoids were analysed by spectrophotometry and High Performance Liquid Chromatography (HPLC). Thirty-one red extremely halophilic bacteria were isolated from saline soil samples collected from a salt farm in Alexandria, Egypt. Among the isolated strains, strain TM exhibited the highest carotenoid-producing ability. Maximum growth of strain TM occurred in the presence of high concentrations of sodium chloride and magnesium sulfate. Growth did not occur when NaCl concentration was lower than 10% and the cells lysed at this concentration. Optimum growth of and carotenoid production by strain TM were realized at 37°C in the presence of 1% yeast extract, 0.75% casamino acids, 25% NaCl, 4% MgSO 4, 0.2% KCl and at pH 7.2 with shaking for 6 d. Strain TM produced 2.06 mg total carotenoids g −1 dry cells, including 0.06 mg of β-carotene and 0.70 mg of canthaxanthin. This is the first report of an extremely halophilic bacterium that produces canthaxanthin.