In mountain ecosystems,plants are sensitive to climate changes,and an entire range of species distribution can be observed in a small area.Therefore,mountains are of great interest for climate–growth relationship ana...In mountain ecosystems,plants are sensitive to climate changes,and an entire range of species distribution can be observed in a small area.Therefore,mountains are of great interest for climate–growth relationship analysis.In this study,the Siberian spruce’s(Picea obovata Ledeb.)radial growth and its climatic response were investigated in the Western Sayan Mountains,near the SayanoShushenskoe Reservoir.Sampling was performed at three sites along an elevational gradient:at the lower border of the species range,in the middle,and at the treeline.Divergence of growth trends between individual trees was observed at each site,with microsite landscape-soil conditions as the most probable driver of this phenomenon.Cluster analysis of individual tree-ring width series based on inter-serial correlation was carried out,resulting in two sub-set chronologies being developed for each site.These chronologies appear to have substantial differences in their climatic responses,mainly during the cold season.This response was not constant due to regional climatic change and the local influence of the nearby Sayano-Shushenskoe Reservoir.The main response of spruce to growing season conditions has a typical elevational pattern expected in mountains:impact of temperature shifts with elevation from positive to negative,and impact of precipitation shifts in the opposite direction.Chronologies of trees,growing under more severe micro-conditions,are very sensitive to temperature during September–April and to precipitation during October–December,and they record both inter-annual and long-term climatic variation.Consequently,it would be interesting to test if they indicate the Siberian High anticyclone,which is the main driver of these climatic factors.展开更多
The industrially important organic compound 1,3-propanediol （1,3-PDO） is mainly used as a building block for the production of various polymers. In the present study, response surface methodology protocol was follow...The industrially important organic compound 1,3-propanediol （1,3-PDO） is mainly used as a building block for the production of various polymers. In the present study, response surface methodology protocol was followed to determine and optimize fermentation conditions for the maximum production of 1,3-PDO using marine-derived Klebsiella pneumoniae HSL4. Four nutritional supplements together with three independent culture conditions were optimized as follows： 29.3 g/L glycerol, 8.0 g/L K2HPO4, 7.6 g/L （NH4）2SO4, 3.0 g/L KH2PO4, pH 7.1, cultivation at 35℃ for 12 h. Under the optimal conditions, a maximum 1,3-PDO concentration of 14.5 g/L, a productivity of 1.21 g/（L＇h） and a conversion of glycerol of 0.49 g/g were obtained. In comparison with the control conditions, fermentation under the optimized conditions achieved an increase of 38.8% in 1,3-PDO concentration, 39.0% in productivity and 25.7% in glycerol conversion in flask. This enhancement trend was further confirmed when the fermentation was conducted in a 5-L fermentor. The optimized fermentation conditions could be an important basis for developing low- cost, large-scale methods for industrial production of 1,3-PDO in the future.展开更多
The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one ...The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one of the microzooplankton grazers in the foodweb. In contrast, green Noctiluca contains a photosynthetic symbiont Pedinomonas noctilucae （a prasinophyte）, but it also feeds on other plankton when the food supply is abundant. In this review, we document the global distribution of these two forms and include the first maps of their global distribution. Red Noctiluca occurs widely in the temperate to sub-tropical coastal regions of the world. It occurs over a wide temperature range of about 10℃ to 25℃ and at higher salinities （generally not in estuaries）. It is particularly abundant in high productivity areas such as upwelling or eutrophic areas where diatoms dominate since they are its preferred food source. Green Noctiluca is much more restricted to a temperature range of 25℃-30℃ and mainly occurs in tropical waters of Southeast Asia, Bay of Bengal （east coast of India）, in the eastern, western and northern Arabian Sea, the Red Sea, and recently it has become very abundant in the Gulf of Oman. Red and green Noctiluca do overlap in their distribution in the eastern, northern and western Arabian Sea with a seasonal shift from green Noctiluca in the cooler winter convective mixing, higher productivity season, to red Noctiluca in the more oligotrophic warmer summer season.展开更多
The purpose of the study was to explore the factors mediating college students＇ radicalization. A sample of 1,116 students was drawn from four different Jordanian universities. The construct validity of the scale was...The purpose of the study was to explore the factors mediating college students＇ radicalization. A sample of 1,116 students was drawn from four different Jordanian universities. The construct validity of the scale was estimated by calculating the correlation between the radicalization items and the negative emotion items. A positive significant relationship was found （0.12, a = 0.000）, a sign of validity of the scale. The scale reliability was also strong and was estimated at 0.90 using Cronbach Alpha. Factor analysis produced five factors explaining 45% of the total variance of radicalization. The first factor labeled ＂political radicalization＂ explained 18.5% of the variance, the second factor ＂religious radicalization＂ explained 12.7%, the third factor ＂violent radicalization＂ explained 6.4% of the variance, the fourth ＂group radicalization＂ accounted for 4%, and the fifth factor ＂social radicalization＂ only accounted for 3% of the total variance. Significant differences in student radicalization were found according to the geographical region of the university （North, Center and South）, F = 14, a = 0.000. However, no significant differences were found in radicalization as it relates to gender, and type of college （i.e., Humanities vs. Pure Sciences）.展开更多
AIM： TO estimate the prevalence of small intestinal bacterial overgrowth （SIBO） in our geographical area （Western Sicily, Italy） by means of an observational study, and to gather information on the use of locally...AIM： TO estimate the prevalence of small intestinal bacterial overgrowth （SIBO） in our geographical area （Western Sicily, Italy） by means of an observational study, and to gather information on the use of locally active, non-absorbable antibiotics for treatment of SIBO.METHODS： Our survey included 115 patients fulfilling the Rome II criteria for diagnosis of irritable bowel syndrome （IBS）; a total of 97 patients accepted to perform a breath test with lactulose （BTLact）, and those who had a positive test, received Rifaximin （Normix , Alfa Wassermann） 1200 mg/d for 7 d; 3 wk after the end of treatment, the BTLact was repeated.RESULTS： Based on the BTLact results, SIBO was present in about 56% of IBS patients, and it was responsible for some IBS-related symptoms, such as abdominal bloating and discomfort, and diarrhoea. 1-wk treatment with Rifaximin turned the BTLact to negative in about 50% of patients and significantly reduced the symptoms, especially in those patients with an alternated constipation/diarrhoea-variant IBS. CONCLUSION： SIBO should be always suspected in patients with IBS, and a differential diagnosis is done by means of a ＂breath test＂. Rifaximin may represent a valid approach to the treatment of SIBO.展开更多
The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-in...The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-inflammatory effect of volatile oil extracted by hydrodistillation of plants was studied using carrageenan induced paw edema. Essential oil （100 mg/kg） and （200 mg/kg） were tested the two plant show high inhibition after 4 h, concentration （200 mg/kg） show high inhibition than （100 mg/kg） after 4 h. Sesqui sabinene hydrate, Azuline and u-Bisabolol are the main constituents of the volatile oil were investigated by capillary GC （gas chromatography） and GC-MS （gas chromatography-mass spectrometry）. The discussion shows the role of chemical compound azulene in inflammatory inhibition.展开更多
To promote long-term studies on the distribution and diversity of marine zooplankton in Indian seas,a comprehensive review has been carried out based on the available literature.Zooplankton studies in Indian waters st...To promote long-term studies on the distribution and diversity of marine zooplankton in Indian seas,a comprehensive review has been carried out based on the available literature.Zooplankton studies in Indian waters started in the early 1900 s,and a plethora of literature has accumulated dealing with various aspects of zooplankton,especially from the Bay of Bengal,Arabian Sea and their associated estuaries and backwaters.From this review,a comprehensive description is offered on the species composition and distribution of zooplankton in the Indian Seas.Emphasis is given to reflect the existing knowledge on the variations in zooplankton species composition in the Bay of Bengal and Arabian Sea.Copepods emerge as the most dominant component in all of these marine waters,as is the case worldwide.Copepods are more diverse in the Bay of Bengal than in Arabian Sea.展开更多
In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasona...In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS （20°N-17°N and 64°E-70°E）, during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number （MPN） and plate counts, revealed ＇variable-physiotypes＇ over a wide range of salinities （0%-25% w/v NaC1）, pH levels （5-8.5）, and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations ＊DWK and ＊PRB, corresponded to （3.08-4.41）×103 cells/mL at 3.5% NaC1 （w/v）, and （2.82-9.49）× 102 cells/mL at 25% （w/v） NaC1 in tryptone-yeast extract broth （TYE）. Plate counts were （1.12-4） × 106 CFU/mL at 0% （w/v） NaC1, （1.28-3.9） × 106 CFU/mL at 3.5% （w/v） NaC1, and （0.4- 7）×104 CFU/mL at 25% NaC1 （w/v） on TYE. One-tenth-strength Zobell＇s gave （0.6-3.74）× 105 CFU/mL at pH 5 to （3.58-7.5）× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains （GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84） was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.展开更多
English is considered as Arab students＇ second language which is not used frequently in their daily conversations. Since writing in English is a challenging experience for Omani students, errors in grammar and senten...English is considered as Arab students＇ second language which is not used frequently in their daily conversations. Since writing in English is a challenging experience for Omani students, errors in grammar and sentence structures were identified in bridging language courses （foundation level 2） in the field of ESL （English as a Second Language}. Learners＇ errors were considered positively as the best sources to identify students＇ limitations in English writing. The present study investigates the structure errors of Omani students＇ writings in English in foundation level 2 at Arab Open University. The focal aim is to study the errors that Ornani students commit when they are using adjectives ＋ nouns, indefinite articles, and subordinate conjunction ＂because＂. Results show that Omani students committed the following common errors： misplacement of adjectives, omission of the indefinite articles, and wrong structure of the subordinate conjunction （because）. The prime aim of this study is to examine the students＇ aforementioned structural errors which are the result of the interference of their mother-tongue. In order to achieve these aims, students were asked to write two different topics. Finally, this research suggests further recommendations for further studies which might ameliorate students＇ learning by adopting appropriate strategies for teaching.展开更多
Soil, water, sediments and air are frequently contaminated with heavy metals. In Saudi Arabia, heavy metals contamination may result from petroleum and mining operations, refining ores, sludge, waste treatment, electr...Soil, water, sediments and air are frequently contaminated with heavy metals. In Saudi Arabia, heavy metals contamination may result from petroleum and mining operations, refining ores, sludge, waste treatment, electrical equipment, paints, alloys, pesticides, batteries and fuel transportation. Microbial processes lead to appreciable and even complete remediation of heavy metals contaminated environments. The chief ways, by which such remediation may be accomplished, include biosorption, bioaugmentation, bioventing, biostimulation, bioaccumulation, biosolubilization, bioreduction, bioprecipitation, mineralization and methylation. Other technologies and methods are fully developed and now are being used in practice, such as heavy metals nanotechnology bioremediation. An area of fungal biotechnology currently in vogue is the use of fungal biornass to absorb metal ions from contaminated solutions. Such biological approaches of metal ions recovery can be used to clean up polluted effluents or to recover precious metal ions from solutions. The present review provides information on fungal bioremediation of heavy metal contamination for use in future studies in Saudi Arabia as well as in the Arabian Gulf Region.展开更多
基金funded by the Russian Foundation for Basic Research (project no.17-04-00315)
文摘In mountain ecosystems,plants are sensitive to climate changes,and an entire range of species distribution can be observed in a small area.Therefore,mountains are of great interest for climate–growth relationship analysis.In this study,the Siberian spruce’s(Picea obovata Ledeb.)radial growth and its climatic response were investigated in the Western Sayan Mountains,near the SayanoShushenskoe Reservoir.Sampling was performed at three sites along an elevational gradient:at the lower border of the species range,in the middle,and at the treeline.Divergence of growth trends between individual trees was observed at each site,with microsite landscape-soil conditions as the most probable driver of this phenomenon.Cluster analysis of individual tree-ring width series based on inter-serial correlation was carried out,resulting in two sub-set chronologies being developed for each site.These chronologies appear to have substantial differences in their climatic responses,mainly during the cold season.This response was not constant due to regional climatic change and the local influence of the nearby Sayano-Shushenskoe Reservoir.The main response of spruce to growing season conditions has a typical elevational pattern expected in mountains:impact of temperature shifts with elevation from positive to negative,and impact of precipitation shifts in the opposite direction.Chronologies of trees,growing under more severe micro-conditions,are very sensitive to temperature during September–April and to precipitation during October–December,and they record both inter-annual and long-term climatic variation.Consequently,it would be interesting to test if they indicate the Siberian High anticyclone,which is the main driver of these climatic factors.
基金Supported by the Scientific Research Project of Marine Public Welfare Industry of China(No.201205020-4)the Knowledge Innovation Project of Chinese Academy of Sciences(No.KSCX2-EW-G-12B)the Administration of Ocean and Fisheries of Guangdong Province(No.GD2012-D01-002)
文摘The industrially important organic compound 1,3-propanediol （1,3-PDO） is mainly used as a building block for the production of various polymers. In the present study, response surface methodology protocol was followed to determine and optimize fermentation conditions for the maximum production of 1,3-PDO using marine-derived Klebsiella pneumoniae HSL4. Four nutritional supplements together with three independent culture conditions were optimized as follows： 29.3 g/L glycerol, 8.0 g/L K2HPO4, 7.6 g/L （NH4）2SO4, 3.0 g/L KH2PO4, pH 7.1, cultivation at 35℃ for 12 h. Under the optimal conditions, a maximum 1,3-PDO concentration of 14.5 g/L, a productivity of 1.21 g/（L＇h） and a conversion of glycerol of 0.49 g/g were obtained. In comparison with the control conditions, fermentation under the optimized conditions achieved an increase of 38.8% in 1,3-PDO concentration, 39.0% in productivity and 25.7% in glycerol conversion in flask. This enhancement trend was further confirmed when the fermentation was conducted in a 5-L fermentor. The optimized fermentation conditions could be an important basis for developing low- cost, large-scale methods for industrial production of 1,3-PDO in the future.
基金the University Grants Council of Hong Kong and its Area of Excellence Program to PJH. KF was supported by a JSPS grant on the ecophysiology of green Noctiluca in the Gulf of Thailand. PMG received funding from NSF （No. OCE-1015980）This is contribution number 4502 from the University of Maryland Center for Environmental Studies. KY Acknowledges Support from the CAS/SAFEA International Partnership Program for Creative Research Teams （No. KZCXZYW-T001）. DMA received partial funding through the NSF/NIEHS Centers for Oceans and Human Health （No. NIEHS P50 ES012742, NSF OCE- 043072 and OCE-0911031）, and through NSF Grant （No. OCE-0850421）+1 种基金 This paper is based on work partially supported by SCOR/LOICZ Working Group 132, supported by the Scientific Committee on Oceanographic Research （SCOR） through grants from the U.S. National Science Foundation （No OCE-0938349 and OCE-0813697） from the Land-Ocean Interactions in the Coastal Zone （LOICZ） Project and the Chinese Academy of Sciences. We thank A. KANA for assistance with the GIS produced maps and LIU Hao for his assistance with the tables and references.
文摘The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one of the microzooplankton grazers in the foodweb. In contrast, green Noctiluca contains a photosynthetic symbiont Pedinomonas noctilucae （a prasinophyte）, but it also feeds on other plankton when the food supply is abundant. In this review, we document the global distribution of these two forms and include the first maps of their global distribution. Red Noctiluca occurs widely in the temperate to sub-tropical coastal regions of the world. It occurs over a wide temperature range of about 10℃ to 25℃ and at higher salinities （generally not in estuaries）. It is particularly abundant in high productivity areas such as upwelling or eutrophic areas where diatoms dominate since they are its preferred food source. Green Noctiluca is much more restricted to a temperature range of 25℃-30℃ and mainly occurs in tropical waters of Southeast Asia, Bay of Bengal （east coast of India）, in the eastern, western and northern Arabian Sea, the Red Sea, and recently it has become very abundant in the Gulf of Oman. Red and green Noctiluca do overlap in their distribution in the eastern, northern and western Arabian Sea with a seasonal shift from green Noctiluca in the cooler winter convective mixing, higher productivity season, to red Noctiluca in the more oligotrophic warmer summer season.
文摘The purpose of the study was to explore the factors mediating college students＇ radicalization. A sample of 1,116 students was drawn from four different Jordanian universities. The construct validity of the scale was estimated by calculating the correlation between the radicalization items and the negative emotion items. A positive significant relationship was found （0.12, a = 0.000）, a sign of validity of the scale. The scale reliability was also strong and was estimated at 0.90 using Cronbach Alpha. Factor analysis produced five factors explaining 45% of the total variance of radicalization. The first factor labeled ＂political radicalization＂ explained 18.5% of the variance, the second factor ＂religious radicalization＂ explained 12.7%, the third factor ＂violent radicalization＂ explained 6.4% of the variance, the fourth ＂group radicalization＂ accounted for 4%, and the fifth factor ＂social radicalization＂ only accounted for 3% of the total variance. Significant differences in student radicalization were found according to the geographical region of the university （North, Center and South）, F = 14, a = 0.000. However, no significant differences were found in radicalization as it relates to gender, and type of college （i.e., Humanities vs. Pure Sciences）.
文摘AIM： TO estimate the prevalence of small intestinal bacterial overgrowth （SIBO） in our geographical area （Western Sicily, Italy） by means of an observational study, and to gather information on the use of locally active, non-absorbable antibiotics for treatment of SIBO.METHODS： Our survey included 115 patients fulfilling the Rome II criteria for diagnosis of irritable bowel syndrome （IBS）; a total of 97 patients accepted to perform a breath test with lactulose （BTLact）, and those who had a positive test, received Rifaximin （Normix , Alfa Wassermann） 1200 mg/d for 7 d; 3 wk after the end of treatment, the BTLact was repeated.RESULTS： Based on the BTLact results, SIBO was present in about 56% of IBS patients, and it was responsible for some IBS-related symptoms, such as abdominal bloating and discomfort, and diarrhoea. 1-wk treatment with Rifaximin turned the BTLact to negative in about 50% of patients and significantly reduced the symptoms, especially in those patients with an alternated constipation/diarrhoea-variant IBS. CONCLUSION： SIBO should be always suspected in patients with IBS, and a differential diagnosis is done by means of a ＂breath test＂. Rifaximin may represent a valid approach to the treatment of SIBO.
文摘The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-inflammatory effect of volatile oil extracted by hydrodistillation of plants was studied using carrageenan induced paw edema. Essential oil （100 mg/kg） and （200 mg/kg） were tested the two plant show high inhibition after 4 h, concentration （200 mg/kg） show high inhibition than （100 mg/kg） after 4 h. Sesqui sabinene hydrate, Azuline and u-Bisabolol are the main constituents of the volatile oil were investigated by capillary GC （gas chromatography） and GC-MS （gas chromatography-mass spectrometry）. The discussion shows the role of chemical compound azulene in inflammatory inhibition.
基金DST-SERB(Govt.of India)for the National Post Doctoral Fellowship(Reference no.PDF/2016/002087)
文摘To promote long-term studies on the distribution and diversity of marine zooplankton in Indian seas,a comprehensive review has been carried out based on the available literature.Zooplankton studies in Indian waters started in the early 1900 s,and a plethora of literature has accumulated dealing with various aspects of zooplankton,especially from the Bay of Bengal,Arabian Sea and their associated estuaries and backwaters.From this review,a comprehensive description is offered on the species composition and distribution of zooplankton in the Indian Seas.Emphasis is given to reflect the existing knowledge on the variations in zooplankton species composition in the Bay of Bengal and Arabian Sea.Copepods emerge as the most dominant component in all of these marine waters,as is the case worldwide.Copepods are more diverse in the Bay of Bengal than in Arabian Sea.
文摘In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS （20°N-17°N and 64°E-70°E）, during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number （MPN） and plate counts, revealed ＇variable-physiotypes＇ over a wide range of salinities （0%-25% w/v NaC1）, pH levels （5-8.5）, and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations ＊DWK and ＊PRB, corresponded to （3.08-4.41）×103 cells/mL at 3.5% NaC1 （w/v）, and （2.82-9.49）× 102 cells/mL at 25% （w/v） NaC1 in tryptone-yeast extract broth （TYE）. Plate counts were （1.12-4） × 106 CFU/mL at 0% （w/v） NaC1, （1.28-3.9） × 106 CFU/mL at 3.5% （w/v） NaC1, and （0.4- 7）×104 CFU/mL at 25% NaC1 （w/v） on TYE. One-tenth-strength Zobell＇s gave （0.6-3.74）× 105 CFU/mL at pH 5 to （3.58-7.5）× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains （GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84） was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.
文摘English is considered as Arab students＇ second language which is not used frequently in their daily conversations. Since writing in English is a challenging experience for Omani students, errors in grammar and sentence structures were identified in bridging language courses （foundation level 2） in the field of ESL （English as a Second Language}. Learners＇ errors were considered positively as the best sources to identify students＇ limitations in English writing. The present study investigates the structure errors of Omani students＇ writings in English in foundation level 2 at Arab Open University. The focal aim is to study the errors that Ornani students commit when they are using adjectives ＋ nouns, indefinite articles, and subordinate conjunction ＂because＂. Results show that Omani students committed the following common errors： misplacement of adjectives, omission of the indefinite articles, and wrong structure of the subordinate conjunction （because）. The prime aim of this study is to examine the students＇ aforementioned structural errors which are the result of the interference of their mother-tongue. In order to achieve these aims, students were asked to write two different topics. Finally, this research suggests further recommendations for further studies which might ameliorate students＇ learning by adopting appropriate strategies for teaching.
文摘Soil, water, sediments and air are frequently contaminated with heavy metals. In Saudi Arabia, heavy metals contamination may result from petroleum and mining operations, refining ores, sludge, waste treatment, electrical equipment, paints, alloys, pesticides, batteries and fuel transportation. Microbial processes lead to appreciable and even complete remediation of heavy metals contaminated environments. The chief ways, by which such remediation may be accomplished, include biosorption, bioaugmentation, bioventing, biostimulation, bioaccumulation, biosolubilization, bioreduction, bioprecipitation, mineralization and methylation. Other technologies and methods are fully developed and now are being used in practice, such as heavy metals nanotechnology bioremediation. An area of fungal biotechnology currently in vogue is the use of fungal biornass to absorb metal ions from contaminated solutions. Such biological approaches of metal ions recovery can be used to clean up polluted effluents or to recover precious metal ions from solutions. The present review provides information on fungal bioremediation of heavy metal contamination for use in future studies in Saudi Arabia as well as in the Arabian Gulf Region.
