Role of Brucella sp. and Gallionella sp. in oil degradation and corrosion

Microbiologically influenced corrosion is responsible for most of the internal corrosion in oil transmission pipelines and storage tanks. In the present study, the role of bacteria on oil degradation and its influence on corrosion have been studied. Two systems (biotic and abiotic) with and without inorganic content and bacteria were employed for studying degradation and corrosion. The aerobic heterotrophic bacterial population (HB) was found to be higher in the presence of inorganic medium than its absence. The oil degradation by microbes was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The corrosion studies were carried out by gravimetric method. It was found that Gallionella sp. degraded aliphatic protons CH₂CH₂ to OCH₂ whereas Brucella sp. converted only aromatic ring to aliphatic protons. The following inferences have been made from this study: (a) inorganic contents in contaminated water determine the oil degradation in storage tanks and transporting pipelines; (b) the degraded product may adsorb on pipeline, which would enhance the rate of microbial corrosion.     

Comparison of denitrification between Paracoccus sp. and Diaphorobacter sp

Denitrification was compared between Paracoccus sp. and Diaphorobacter sp. in this study, both of which were isolated from activated sludge of a denitrifying reactor. Denitrification of both isolates showed contrasting patterns, where Diaphorobacter sp. showed accumulation of nitrite in the medium while Paracoccus sp. showed no accumulation. The nitrate reduction rate was 1.5 times more than the nitrite reduction in Diaphorobacter sp., as analyzed by the resting state denitrification kinetics. Increasing the nitrate concentration in the medium increased the nitrite accumulation in Diaphorobacter sp., but not in Paracoccus sp., indicating a branched electron transfer during denitrification. Diaphorobacter sp. was unable to denitrify efficiently at high nitrate concentrations from 1 M, but Paracoccus sp. could denitrify even up to 2 M nitrate. Paracoccus sp. was found to be an efficient denitrifier with insignificant amounts of nitrite accumulation, and it could also denitrify high amounts of nitrate up to 2 M. Efficient denitrification without accumulation of intermediates like nitrite is desirable in the removal of high nitrates from wastewaters. Paracoccus sp. is shown to suffice this demand and could be a potential organism to remove high nitrates effectively.     

Legionella moravica sp. Nov. and Legionella brunensis sp. Nov. Isolated from cooling-tower water

Two Legionella-like organisms were isolated from cooling-tower water samples in Czechoslovakia. They were presumptively identified as legionellae by their growth on buffered charcoal-yeast extract agar (BCYE) containing L-cysteine and their absence of growth on BCYE without L-cysteine. Both strains contained predominantly branch-chained cellular fatty acids and were therefore definitively placed in the genus Legionella. They were serologically distinct from other described Legionella species and were shown by DNA studies to constitute two new Legionella species, Legionella moravica (type strain 316-36; ATCC 43877) and Legionella brunensis (type strain 441-1; ATCC 43878).     

Production of Biodegradable Polymer from Agro-Wastes in Alcaligenes sp. and Pseudomonas sp.

The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost-effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 accumulates higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the Pseudomonas sp. RZS1 follows the Monod model more closely than A. faecalis RZS4. Both the cultures degrade their PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low-cost sources of nutrients for the growth and production of PHB and other metabolites. Their use would lower the production cost of PHB and the low-cost production will reduce the sailing price of PHB-based products. This would promote the large-scale commercialization and popularization of PHB as an ecofriendly bioplastic/biopolymer.     

克雷伯氏菌和伯克霍尔德氏菌复合菌群催化三硝基甲苯降解

 通过摇瓶实验研究了克雷伯氏菌 (S1) 和伯克霍尔德氏菌 (S2) 复合菌群 (简称 S) 降解三硝基甲苯 (TNT) 的特性和机理. 结果表明, 在外加碳源和氮源时, 100 mg/L TNT 在 16 h 内可被菌群 S 完全去除. 只外加碳源时, TNT 的最高去除率为 80%; 只加入氮源时, 仍可除去 12% 的 TNT. 在 S1 催化体系中检测到较高活性硝基还原酶的存在, 该酶催化 TNT 转化为缩合中间产物二硝基双偶氮甲苯, 其分子量为 326. 但是只有 S1 和 S2 共存才能产生高活性的甲苯双加氧酶和邻苯二酚 2,3-双加氧酶, 两类酶共同催化中间产物的开环分解. 伴随着二硝基双偶氮甲苯的开环分解, 硝基脱落生成 NO2–, 后者进一步氧化生成 NO3–. 通过 S1 和 S2 的协同作用, 实现了 TNT 的好氧开环和硝基脱落, 该结果表明在 TNT 生物催化降解中复合菌群比单一菌株更具优势和潜力.     

Triterpenoids fromAbies sp.

The structure of the molecule of a new trinorlanostane hydroxyketone obtained by alkali treatment of total triterpenoid acids from the ether extract of Siberian fir needles was established using NMR spectra and X-ray analysis.For Part 15 see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 748–751. March, 1996.     

Synergistic Effect of Sarocladium sp. and Cryptococcus sp. Co-Culture on Crude Oil Biodegradation and Biosurfactant Production

This study was conducted to evaluate the co-culture ability of two yeast (Sarocladium sp. and Cryptococcus sp.) isolates as compared to their individual cultures in surfactant production and oil degradation. The results showed that individual culture of each strain was capable of producing surfactant, degrading oil, and pyrene; also, a synergistic effect was observed when a co-culture was applied. Oil removal and biomass production were 28 and 35% higher in the co-culture than in individual cultures, respectively. To investigate the synergistic effects of mix culture on oil degradation, the surface tension, emulsification activity (EA), and cell surface hydrophobicity of individual and co-culture were studied. A comparison between the produced biosurfactant and chemical surfactants showed that individual culture of each yeast strain could reduce the surface tension like SDS and about 10% better than Tween 80. The results showed that the microbial consortium could reduce the surface tension more, by 10 and 20%, than SDS and Tween 80, respectively. Both individual cultures of Sarocladium sp. and Cryptococcus sp. showed good emulsification activity (0.329 and 0.412, respectively) when compared with a non-inoculated medium. Emulsification activity measurement for the two yeast mix cultures showed an excellent 33 and 67% increase as compared to the individual culture of Sarocladium sp. and Cryptococcus sp., respectively. The cell surface hydrophobicity of Sarocladium sp. and Cryptococcus sp. increased (38 and 85%) when the cells were treated with pyrene as a hydrophobic substrate for four generations. Finally, a 40% increase for pyrene degradation was measured in a co-culture of the two yeast mix culture. According to the results of the present study, the co-culture system exhibited better performance and this study will enhance the understanding of the synergistic effects of yeast co-culture on oil degradation.

     

Lipids of Potomogeton sp.

Institute of the Ecology of the Volga Basin, Russian Academy of Sciences, Tol'yatti. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 850–852, November–December, 1991.     

Seimatoric acid and colletonoic acid:Two new compounds from the endophytic fungi,Seimatosporium sp.and Colletotrichum sp.

A new metabolite,named seimatoric acid(1),representing a new oxobutanoic acid derivative has been isolated from Seimatosporium sp., in addition to four known compounds viz.,2-hydroxymethyl-4β,5α,6β-trihydroxycyclohex-2-enone(2),(-)-phyllostine(3),(+)-epiepoxydon(4) and(+)-epoxydon monoacetate(5).Similarly one new benzoic acid derivative,named colletonoic acid(6) was isolated from the ethyl acetate fraction of Colletotrichum sp.The structures of the new compounds were elucidated by detailed ~1 H NMR,~(13)C NMR,COSY,HMQC.HMBC spectroscopic analysis,and HR-E1-MS.Seimatoric acid(1)was also isolated from another taxonomical unidentified fungal strain 4295 in ourgroup.The structures of the known compounds were elucidated by their spectral data comparison to literature data.Preliminary studies showed that colletonoic acid(6) showed good antibacterial,antifungal,and antialgal activities.     

Lipids from seeds ofAmaranthus sp.

The composition of free, bound, and strongly bound lipids ofAmaranthus sp. is studied. The fatty-acid composition of separate lipid classes is determined. Unsaponified sterols that were fractionated by TLC into five components were isolated. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (99871) 120 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 586–589, September–October, 1999.     

Isolation and characterization of thermophilic benzothiophene-degrading Mycobacterium sp.

A bacterial strain, SWU-4, capable of using benzothiophene (BT) as a sole carbon and energy source was isolated from a petroleum-contaminated site in Thailand and identified by 16S rRNA gene sequence analysis to be in the genus of Mycobacterium. The strain was Gram-positive, nonspore former, and grew at 50° C. Colonies of the strain on nutrient agar were rod-shaped, smooth with a convex surface, slightly mucoid, and yellow pigmented. The thermophilic Mycobacterium sp. strain SWU-4 rapidly degraded 2% (w/v) BT at 50°C. Interestingly, this strain was able to degrade a wide variety of organosulfur compounds including thiophene, bromo(α)thiophene, and 3-methylthiophene in liquid minimum medium at 50°C, which will be beneficial for industrial applications.     

Uptake and Reduction of Arsenate by Dunaliella sp.

Uptake and reduction of arsenate [AS(V)] by Dunaliella sp. cells were determined to investigate the metabolic processes of arsenic in the alga. Cellular uptake of arsenic by Dunaliella sp. cells was markedly affected by the form of arsenic in the medium. The content of arsenic taken up by Dunaliella sp. cells increased rapidly with time on addition of As(V) to the medium. However, in the case of addition of arsenite [As(III)], the gradient of arsenic uptake by Dunaliella sp. cells was low, and arsenic content was small. In the water-soluble fraction of arsenic taken up by Dunaliella sp. cells with exposure to As(V), arsenic was in the forms of organic arsenic, As(V) and As(III). The content of As(V) in the water-soluble fraction increased with exposure time. The content of As(III) also increased with time, but remained constant after 5 h of exposure. On the other hand, organic arsenic content was small and did not increase with time. It was found that Dunaliella sp. takes up As(V) and readily reduces it to As(III)     

Cellulase and xylanase production byAspergillus sp. G-393

Applied Biochemistry and Biotechnology - The production of cellulase and xylanase can be achieved byAspergillus sp. G-393 using agricultural wastes. Enzymes produced by the strain G-393 were stable...     

A New Perylenequinone from Hypomyces sp.

Some metabolites of fungi and plants containing perylenequinones have been used as folk medicine for the treatment of many diseases1,2. A filamentous fungus, Ascomy-cetes Hypocreaceae Hypomyces (Fr.) Tul. sp., was found from the northwestern mountains of Yunnan Province, and cultured successfully in the laboratory. A new perylenequinone, named hypomycin A (1), was isolated from its mycelia. In this paper the structure elucidation of 1 was described. Figure 1 The structure of compound 1 Fig…     

针荔海绵Raphiedotethya sp.的次生代谢产物

从海南省三亚附近海域采集的针荔海绵Raphiedotethya sp.中分离到1个新神经酰胺和1个甾醇苷.经波谱分析和化学分析确定了它们的化学结构依次为:(2s,3S,4R,2'R)-N-(2'-羟基-二十二碳酰基)-1,3,4-三羟基-2.氨基-二十一烷(1)和4-O-[β-D-吡喃木糖苷]-孕甾-20-烯-3β,4α-二醇(2).