scholarly journals Statistical Optimisation of Diesel Biodegradation at Low Temperatures by an Antarctic Marine Bacterial Consortium Isolated from Non-Contaminated Seawater

2021 ◽  
Vol 9 (6) ◽  
pp. 1213
Author(s):  
Nur Nadhirah Zakaria ◽  
Claudio Gomez-Fuentes ◽  
Khalilah Abdul Khalil ◽  
Peter Convey ◽  
Ahmad Fareez Ahmad Roslee ◽  
...  
Keyword(s):  
Nitrogen Concentration ◽  
Optimal Growth ◽  
Bacterial Consortium ◽  
Growth Conditions ◽  
Anthropogenic Sources ◽  
Cold Temperatures ◽  
North West ◽  
The North ◽  
Degrading Bacteria ◽  
Diesel Biodegradation

Hydrocarbon pollution is widespread around the globe and, even in the remoteness of Antarctica, the impacts of hydrocarbons from anthropogenic sources are still apparent. Antarctica’s chronically cold temperatures and other extreme environmental conditions reduce the rates of biological processes, including the biodegradation of pollutants. However, the native Antarctic microbial diversity provides a reservoir of cold-adapted microorganisms, some of which have the potential for biodegradation. This study evaluated the diesel hydrocarbon-degrading ability of a psychrotolerant marine bacterial consortium obtained from the coast of the north-west Antarctic Peninsula. The consortium’s growth conditions were optimised using one-factor-at-a-time (OFAT) and statistical response surface methodology (RSM), which identified optimal growth conditions of pH 8.0, 10 °C, 25 ppt NaCl and 1.5 g/L NH4NO3. The predicted model was highly significant and confirmed that the parameters’ salinity, temperature, nitrogen concentration and initial diesel concentration significantly influenced diesel biodegradation. Using the optimised values generated by RSM, a mass reduction of 12.23 mg/mL from the initial 30.518 mg/mL (4% (w/v)) concentration of diesel was achieved within a 6 d incubation period. This study provides further evidence for the presence of native hydrocarbon-degrading bacteria in non-contaminated Antarctic seawater.

Distribution of oil-degrading bacteria in the north-west Arabian Gulf

1990 ◽  
Vol 21 (1) ◽  
pp. 38-40 ◽  
Author(s):  
S.M. Shamshoom ◽  
T.S. Ziara ◽  
A.N. Abdul-Ritha ◽  
A.E. Yacoub
Keyword(s):  
Arabian Gulf ◽  
North West ◽  
The North ◽  
Degrading Bacteria

scholarly journals VARIABILITY OF ANATOMICAL FEATURES OF VEGETATIVE AND GENERATIVE ORGANS OF NITRARIA SCHOBERI L. IN SULAK POPULATION OF DAGHESTAN

2018 ◽  
Vol 13 (2) ◽  
pp. 73-84
Author(s):  
Zagirbeg M. Аsadulaev ◽  
Magomed G. Gadzhiataev ◽  
Zulfira R. Ramazanova
Keyword(s):  
Growth Conditions ◽  
Dispersion Analysis ◽  
Consolidation Process ◽  
Mahalanobis Distances ◽  
Self Identity ◽  
North West ◽  
The North ◽  
Caspian Lowland ◽  
The Village ◽  
Generative Organs

Aim. The work is devoted to the study of intrapopulation variability of the Sulak population of Nitraria schoberi L. Methods. The materials for this article were samples of vegetative and generative organs (shoot, leaf, fruit, seed) collected in 2015 in the natural population of N. schoberi in the Caspian lowland to the north-west of the village of Sulak. Results. The studied individuals of N. schoberi differ both in absolute indices of characteristics and in the degree of their variability, which is related both to micro growth conditions and to their genetic and age specific features. The prevalence of shrubs with a smaller diameter we associate with the relative youth of the population. In the semi-arid conditions of the Caspian lowland of Dagestan, N. schoberi bushes play a big role in the sand consolidation process, forming dunes and barrows, which is related to their ability to grow in diameter forming the beds during the rooting of lodging boughs. Conclusion. On the basis of discriminative analysis on the set of the characteristics of the leaf, the maximum self-identity of the 8th bush (80%) was determined, and the 5th bush (100%), on the basis of the fruit and seed, as confirmed by the Mahalanobis distances. The evaluation of signs of vegetative organs according to the results of dispersion analysis showed that the influence of the conditions of the year (h2– 20,8%) is higher than the influence of the characteristics of the bushes themselves (h2– 3,8%). Of generative characters, the greatest contribution is made by the length of the seed (h2– 63,6). 

scholarly journals Growth Optimisation and Kinetic Profiling of Diesel Biodegradation by a Cold-Adapted Microbial Consortium Isolated from Trinity Peninsula, Antarctica

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 493
Author(s):  
Ahmad Fareez Ahmad Roslee ◽  
Claudio Gomez-Fuentes ◽  
Nur Nadhirah Zakaria ◽  
Nor Azmi Shaharuddin ◽  
Azham Zulkharnain ◽  
...  
Keyword(s):  
Microbial Consortium ◽  
Substrate Inhibition ◽  
Total Petroleum Hydrocarbons ◽  
Microbial Consortia ◽  
Cold Adapted ◽  
North West ◽  
Optimum Growth Temperature ◽  
The North ◽  
West Antarctic ◽  
Diesel Biodegradation

Pollution associated with petrogenic hydrocarbons is increasing in Antarctica due to a combination of increasing human activity and the continent’s unforgiving environmental conditions. The current study focuses on the ability of a cold-adapted crude microbial consortium (BS24), isolated from soil on the north-west Antarctic Peninsula, to metabolise diesel fuel as the sole carbon source in a shake-flask setting. Factors expected to influence the efficiency of diesel biodegradation, namely temperature, initial diesel concentration, nitrogen source type and concentration, salinity and pH were studied. Consortium BS24 displayed optimal cell growth and diesel degradation activity at 1.0% NaCl, pH 7.5, 0.5 g/L NH4Cl and 2.0% v/v initial diesel concentration during one-factor-at-a-time (OFAT) analyses. The consortium was psychrotolerant based on the optimum growth temperature of 10‒15 °C. In conventionally optimised media, the highest total petroleum hydrocarbons (TPH) mineralisation was 85% over a 7-day incubation. Further optimisation of conditions predicted through statistical response-surface methodology (RSM) (1.0% NaCl, pH 7.25, 0.75 g/L NH4Cl, 12.5 °C and 1.75% v/v initial diesel concentration) boosted mineralisation to 95% over a 7-day incubation. A Tessier secondary model best described the growth pattern of BS24 in diesel-enriched medium, with maximum specific growth rate, μmax, substrate inhibition constant, Ki and half saturation constant, Ks, being 0.9996 h−1, 1.356% v/v and 1.238% v/v, respectively. The data obtained suggest the potential of microbial consortia such as BS24 in bioremediation applications in low-temperature diesel-polluted soils.

Bacterial diversity in surface sediments from the continental shelf and slope of the North West gulf of Mexico and the presence of hydrocarbon degrading bacteria

2020 ◽  
Vol 150 ◽  
pp. 110590 ◽  
Author(s):  
Diana Ramírez ◽  
Leticia Vega-Alvarado ◽  
Blanca Taboada ◽  
Alejandro Estradas-Romero ◽  
Luis Soto ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Continental Shelf ◽  
Bacterial Diversity ◽  
Surface Sediments ◽  
North West ◽  
The North ◽  
Degrading Bacteria

SEM and TEM observations of sperm development in the testis of the freshwater fish Oreochromis mossambicus

1990 ◽  
Vol 48 (3) ◽  
pp. 58-59
Author(s):  
Daryl A. Cornish ◽  
George L. Smit
Keyword(s):  
Morphological Characteristics ◽  
Oreochromis Mossambicus ◽  
Breeding Cycle ◽  
Limited Information ◽  
North West ◽  
The North ◽  
Sem And Tem ◽  
Sperm Development ◽  
Ultrastructural Characteristics ◽  
The University

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.

The North West Passage

2014 ◽  
Author(s):  
Roald Amundsen ◽  
Godfred Hansen
Keyword(s):  
North West ◽  
The North
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