Mud Samples Research Articles

Evaluation of Local Clays from Edo and Delta State as Feedstock in Drilling Fluid Formulation

This work investigates the suitability of clay samples collected from Ogwashi-Ukwu and Oyede in Delta State as well as Ikpeshi and Afuze in Edo State for drilling mud formulation. The American Petroleum Institute (API) Standard for drilling mud formulation was adopted using 350 ml of water and 21.0 g of fresh unweathered clay samples collected at 5 ft depth from the mentioned location. The Clay Samples were processed (Weighed, dried, and sieved) and the drilling mud formulated with other additives (Carboxyl Methyl Cellulose, NaOH and Barite). The results from the four samples showed that the pH of Ikpeshi was alkaline while the other samples were acidic. When the mud was mixed with NaOH at 0.5 g, 1.0 g, 1.5 g, 2.0 g, 2.5 g and 3.0 g, the pH rose to 13 and 14 for the Ikpeshi and Ogwashi-Ukwu, while the pH values of the mud formulated with the standard clay gave 9 and increased to 13 when 3.0g of NaOH was added. The mud densities for the four mud samples formulated were within 8.40 to 8.60ppg before addition of chemical additives. After beneficiation addition with Barite, the densities of the four formulated mud rose and almost equal to that of the standard mud of 8.95 ppg at 3 g additive. The plastic viscosity of the locally formulated mud were within 1 to 2 cp before adding cmc and increased to 30cp for Ikpeshi mud, 27 cp for Ogwashi-Ukwu, 17 cp for Afuze and 18 cp for Oyede. The filtration rate for Afuze and Ikpeshi mud was 33 ml and 36 ml for 30 mins and may need additional filtration agent to be up to standard. The results have shown that the Nigeria Clay can be used with beneficiation. Therefore, the production of mud materials locally, should be encourage to reduce the cost of drilling by avoiding importation.

Investigation of potential inhibitor properties of violacein against HIV-1 RT and CoV-2 Spike RBD:ACE-2.

A violacein-producing bacterium was isolated from a mud sample collected near a hot spring on Kümbet Plateau in Giresun Province and named the GK strain. According to the phylogenetic tree constructed using 16S rRNA gene sequence analysis, the GK strain was identified and named Janthinobacterium sp. GK. The crude violacein pigments were separated into three different bands on a TLC sheet. Then violacein and deoxyviolacein were purified by vacuum liquid column chromatography and identified by NMR spectroscopy. According to the inhibition studies, the HIV-1 RT inhibition rate of 1 mM violacein from the GK strain was 94.28% and the CoV-2 spike RBD:ACE2 inhibition rate of 2 mM violacein was 53%. In silico studies were conducted to investigate the possible interactions between violacein and deoxyviolacein and three reference molecules with the target proteins: angiotensin-converting enzyme 2 (ACE2), HIV-1 reverse transcriptase, and SARS-CoV-2 spike receptor binding domain. Ligand violacein binds strongly to the receptor ACE2, HIV-1 reverse transcriptase, and SARS-CoV-2 spike receptor binding domain with a binding energy of −9.94 kcal/mol, −9.32 kcal/mol, and −8.27 kcal/mol, respectively. Deoxyviolacein strongly binds to the ACE2, HIV-1 reverse transcriptase, and SARS-CoV-2 spike receptor binding domain with a binding energy of −10.38 kcal/mol, -9.50 kcal/mol, and −8.06 kcal/mol, respectively. According to these data, violacein and deoxyviolacein bind to all the receptors quite effectively. SARS-CoV-2 spike protein and HIV-1-RT inhibition studies with violacein and deoxyviolacein were performed for the first time in the literature.Graphical abstract

Investigation of Pyrolysis Behavior of Sewage Sludge by Thermogravimetric Analysis Coupled with Fourier Transform Infrared Spectrometry Using Different Heating Rates

In this study, pyrolysis of municipal sewage sludge samples from different sources including cattle and chicken manure as well as brook mud, was investigated using a thermogravimetric analysis coupled with a Fourier transform infrared spectrometer (TG-FTIR) at different heating rates (25, 50 and 100 °C/min). In order to determine the kinetic parameters, Arrhenius, model-free Kissinger–Akira–Sunose (KAS), as well as Friedman and Flynn–Wall–Ozawa (FWO) methods were compared. The thermogravimetric results revealed that pyrolysis involved different stages, and that the main decomposition reactions took place in the range of 200–600 °C. In this range, decomposition of biodegradable components (e.g., lipids and polysaccharides), proteins and carbohydrates occurred; meanwhile, there were samples (e.g., cattle manure, brook mud) in which the decomposition step could be observed even at temperatures above 700 °C. According to the Arrhenius method, the activation energies of the first decomposition stage were between 25.6 and 85.4 kJ/mol, while the activation energies of the second and third stages were in the ranges of 11.4–36.3 kJ/mol and 20.2–135 kJ/mol, respectively. The activation energies were also calculated by the KAS, Friedman and FWO methods, which were in the range of 100–300 kJ/mol for municipal sewage sludge or distillery sludge, and ranged between 9.6 and 240 kJ/mol for cattle manure, chicken manure and brook mud samples.

Performance of Equilibrium Zeolite in Water-Based Mud at Elevated Temperature Conditions

This study looks at the performance of nano equilibrium zeolite treated drilling fluids at high temperatures conditions, and their potential as alternatives for oil-based muds (OBM). Mud samples for this study were prepared and aged with the equilibrium zeolite nanoparticles concentrations of 0.0 g, 0.5 g, 1.0 g and 1.5 g. Tests were performed to determine the rheological, filtration control properties, the pH and consequently the thermal stability of the study mud samples over a temperature range of 120 °F to 360 °F. One sample without the equilibrium zeolite served as a control for the study. From the results obtained, all the nano samples had their rheological properties not exhibiting much significant variation with temperature, thus they were more thermally stable, with the optimum nanoparticle concentration being 1.5 g. It was also hypothesized that the nano equilibrium zeolite behaved as thinners, since they were able to reduce the shear stresses, yield points, plastic viscosities and gel strengths of the mud samples as temperature was varied incrementally. It was therefore concluded that the optimum concentration of aged equilibrium zeolite has the potential to act as a thermal stability additive for Water Based Mud systems (WBMs).

Experimental Study on Damage Characteristics of Solidified Mud under Coupling Action of Freeze-Thaw Cycle and Chloride Salt

The physical properties of solidified mud will deteriorate under the combined action of freezing-thawing cycle and chlorine salt, which will affect the safety and stability of solidified mud engineering. In order to study the damage characteristics of solidified mud under the action of freeze-thaw cycle and chloride salt, the solidified mud samples were soaked in different concentrations of sodium chloride solution and treated with freeze-thaw cycle. Besides, the unconfined compressive strength test was carried out to study the damage characteristics of the samples caused by different concentrations of sodium chloride solution and freeze-thaw cycles. The test results show the following. (1) Under the action of freeze-thaw cycle and sodium chloride solution, the surface of the sample deteriorated in varying degrees. With the increase in freeze-thaw cycle times and sodium chloride solution concentration, the mass loss of the sample was greater. (2) Under the action of chlorine salt and freeze-thaw cycle, the strength of the sample decreases with the increase in freeze-thaw cycle times. With the increase in the concentration of sodium chloride solution, the strength of the sample decreases and the damage degree increases gradually. (3) Under the action of freeze-thaw cycle, the internal pores of the samples gradually expand and more honeycomb holes appear, and the content of hydration products is higher. As the concentration of sodium chloride solution increases, the particle connection inside the sample gradually weakens, and the sample is more likely to be damaged.

Roseicella aquatilis sp. nov., isolated from freshwater lake.

A novel Gram-stain-negative, non-motile, ellipsoidal-shaped, red-pigmented, facultatively aerobic strain designated NE82T was isolated from mud sample from Jiugongli Lake in Inner Mongolia Autonomous Region, China. Optimal growth occurred at 28-33°C (range 15-42°C) and pH 7.0-7.5 (range 5.5-8.5) with 0% (w/v) NaCl (range 0-1.0%). Cells of strain NE82T were 0.4-0.9μm in diameter, catalase-positive and oxidase-negative. Q-10 was the sole respiratory quinone and the major cellular fatty acids (> 10%) in strain NE82T were summed feature 8 (C18:1 ω7c and C18:1 ω6c). The polar lipids of strain NE82T were phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, an unidentified aminophospholipid and four unidentified phospholipids. The G+C content of the genomic DNA was 72.0mol%. Based on the 16S rRNA gene sequence, strain NE82T showed the highest similarity (97.2%) to Roseicella frigidaeris DB1506T within the family Acetobacteraceae, thus representing a novel species of the genus Roseicella, for which the name Roseicella aquatilis sp. nov. is proposed. The type strain is NE82T (= KCTC 62412T = MCCC 1H00292T).

Establishment and application of a TaqMan probe-based qPCR for the detection of Enterocytozoon hepatopenaei in shrimp Litopenaeus vannamei.

Enterocytozoon hepatopenaei (EHP) is a common parasite that invades the epithelial cytoplasm in the hepatopancreas of shrimp Litopenaeus vannamei and results in slow growth of the host shrimps to cause significant economic loss in shrimp aquaculture. In this study, a TaqMan probe-based qPCR for quantitative detection of EHP was established. A pair of specific primers and a TaqMan probe were designed based on the sequence of cysteine desulfurase gene (NFS1) of EHP. The standard curve between cycle threshold (Ct) and the logarithmic starting quantity (SQ) of the template was determined as Ct = - 3.231 lg (SQ) + 40.638, with a correlation coefficient (R2) of 0.998 and an amplification efficiency of 103.9%. The lower limit of quantification was 1.67 × 101 copies/μL for this TaqMan probe-based qPCR and 1.67 × 103 copies/μL for the conventional PCR. The TaqMan probe-based qPCR established in the research was 100 times more sensitive than the conventional PCR method. In addition, the results of clinical sample detection indicated that the present technique was efficient in detecting EHP in the hepatopancreas, feces, water, and pond bottom mud samples. Therefore, the established TaqMan probe-based qPCR is a suitable technique for detecting EHP in both shrimp and aquatic environment samples.

Evaluating the influence of graphene nanoplatelets on the performance of invert emulsion drilling fluid in high-temperature wells

The oil-based mud is preferred to drill highly technical and challenging formations due to its superior performance. However, the inadequate chemical and thermal stability of conventional additives have greatly influenced the performance of oil-based mud at high-temperature conditions. Therefore, it is critical to design an oil-based mud with additives that withstand and improve its performance at high-temperature conditions. The nanoparticles have emerged as an alternative to the conventional additives that can significantly enhance the rheological and filtration characteristics of oil-based mud at high-temperature conditions. In this research study, a novel formulation of OBM enhanced with GNP is formulated, and its performance at high-temperature conditions is investigated. An extensive experimental study has been performed to study the effect of graphene nanoplatelets on the rheological and filtration properties along with flow behaviour, viscoelastic properties, electrical stability and barite sagging of oil-based mud at high temperatures. The graphene nanoplatelets are characterised to ascertain their purity and morphology. The result shows that the graphene nanoplatelets exhibited efficient performance and improved the rheological and filtration properties of oil-based mud. The plastic viscosity and yield point are improved by 11% and 42%, with a concentration of 0.3 ppb. Similarly, the gel strength and barite sagging tendency are enhanced by 14% and 2%, respectively. The filtration loss is also significantly decreased by up to 62% and 46%, with 0.5 ppb concentration at 100 and 120 °C. The addition of GNP results in the formation of a thin mud cake compared to the base mud sample. The rheological modelling recommends the shear-thinning behaviour of oil-based mud (n < 1), which is correlated with the Herschel–Bulkley model. An Artificial Neural Network model is developed to predict the viscosity of OBM based on the four input parameters (concentration of nanoparticles, temperature, shear rate and shear stress). The results demonstrate that graphene nanoplatelets have a favourable impact on the performance of oil-based mud. The addition of graphene nanoplatelets, even at small concatenation, has significantly improved the properties of oil-based mud at high-temperature.Graphical abstract

Bioaccumulation, tolerance, and removal of U(VI) and Th(IV) by a novel thermophilic Bacillus cereus ST14 isolated from hot spring mud samples in Afyonkarahisar, Turkey

Bioaccumulation, tolerance, and removal of U(VI) and Th(IV) by a novel thermophilic Bacillus cereus ST14 isolated from hot spring mud samples in Afyonkarahisar, Turkey

Influence of Anaerobic Degradation of Organic Matter on the Rheological Properties of Cohesive Mud from Different European Ports

The presence of clay-organic flocs in cohesive mud results in a complex rheological behavior of mud, including viscoelasticity, shear-thinning, thixotropy and two-step yielding. In this study, the effect of microbial degradation of organic matter on the rheological properties of mud samples, collected from different ports, was examined. The mud samples were collected from five different European ports (Port of Antwerp (PoA), Port of Bremerhaven (PoB), Port of Emden (PoE), Port of Hamburg (PoH) and Port of Rotterdam (PoR)), displaying varying sediment properties. The rheological analysis of fresh and degraded mud samples was performed with the help of several tests, including stress ramp-up tests, amplitude sweep tests, frequency sweep tests, time-dependent tests and structural recovery tests. The results showed: (i) a significant decrease in yield stresses and complex modulus after organic matter degradation for mud samples from PoA, PoH and PoR, (ii) a negligible change in rheological properties (yield stresses, crossover amplitude and complex modulus) for mud samples from PoB, and (iii) a significant increase in rheological properties for mud samples from PoE. For time-dependent tests, mud samples from PoB showed a substantial increase in hysteresis (~50% mean value) as compared to the changes in yield stresses and crossover amplitude. The analysis of gas production during degradation of organic matter showed a (i) significant release of carbon per g dry matter for mud samples from PoA, PoH and PoR, (ii) lower carbon release per g dry matter for mud samples from PoB, and (iii) a negligible carbon release per g dry matter for mud samples from PoE, which corresponded well with the change in rheological properties.

Unique Cyclized Thiolopyrrolones from the Marine-Derived Streptomyces sp. BTBU20218885.

Two new cyclized thiolopyrrolone derivatives, namely, thiolopyrrolone A (1) and 2,2-dioxidothiolutin (2), together with the kn own compound, thiolutin (3) were identified from a marine-derived Streptomyces sp. BTBU20218885, which was isolated from a mud sample collected from the coastal region of Xiamen, China. Their chemical structures were determined using spectroscopic data, including HRESIMS, 1D and 2D NMR techniques. 1 possessed a unique unsymmetrical sulfur-containing thiolopyrrolone structure. All the compounds were tested for bioactivities against Staphylococcus aureus, Escherichia coli, Bacille Calmette–Guérin (BCG), Mycobacterium tuberculosis, and Candida albicans. 1 displayed antibacterial activities against BCG, M. tuberculosis, and S. aureus with minimum inhibitory concentration (MIC) values of 10, 10, and 100 μg/mL, respectively. Thiolutin (3) showed antibacterial activities against E. coli, BCG, M. tuberculosis, and S. aureus with MIC values of 6.25, 0.3125, 0.625, and 3.125 μg/mL, respectively.

Reduction of formation damage in horizontal wellbores by application of nano-enhanced drilling fluids: Experimental and modeling study

One of the basic challenges during drilling horizontal wellbores is the damage induced by invasion of mud filtrate into the formation. Addition of nanoparticles to drilling fluids has been recognized as a measure of control and reduction of filtrate invasion, which is the primary mechanism of the aforementioned formation damage. Despite notable advances in composing Nano-enhanced drilling fluids, the role of nanoparticle hydrophobicity on performance of the fluids has not been well studied. This study is based on a combined experimental-numerical methodology. In the experimental section, a procedure to find the optimum composition of Nano-enhanced water-based samples, containing nanoparticles of hydrophilic/hydrophobic silica and lipophilic clay to minimize the formation damage associated with mud circulation is recommended. The main idea was to investigate the effect of hydrophobicity of nanoparticles on damage reduction and furthermore, discover how other properties such as types/concentration of nanoparticles/micro-sized additives, temperature and pressure would affect functionality and characteristics of drilling fluids. In order to more accurately and practically investigate any probable enhancements in performance of fluid samples a particular radial filtration setup was designed and used; then, functionality of mud samples was examined on grain packed porous media at radial flooding flow condition. Results revealed that samples containing 0.2 wt. % hydrophobic nanosilica had the best functionality with returned permeability of 68.4% and 51.1% for the cases of water saturated and oil saturated porous media, respectively. In the modeling section, mass balance and momentum equations were solved simultaneously by using elapsed time data. Permeability as well as thickness of mud cake formed on the wellbore wall were evaluated and compared for different Nano-enhanced mud samples. Results showed that nano-enhanced drilling fluid samples generated thinner mud cakes with lower permeability values during quite shorter period of time. Results of this work might be helpful to better understand the behavior of nano-enhanced drilling fluids in radial porous systems at different conditions of nanoparticles hydrophobicity and applicable to minimize the induced formation damage during drilling of the horizontal section of a production well. • A combined experimental-numerical methodology is used to evaluate any possible enhancement in characteristics of drilling fluid, mud cake and damaging potential. • The effects of hydrophobicity of nanoparticles along with types/concentration of nanoparticles/ micro-sized additives, temperature and pressure on characteristics of drilling fluids are investigated. • A particular radial filtration setup is designed and used to more precisely evaluate the damaging potential of mud samples and to measure permeability recovery after mud filtrate invasion. • Samples containing 0.2 wt. % hydrophobic nanosilica had the best functionality with return permeability of 68.4% and 51.1% in water-saturated and oil-saturated porous media, respectively. • In the modeling section, mass balance and momentum equations are solved simultaneously; permeability and thickness of filter cake are evaluated and compared for each of mud samples.

A novel salt-tolerant strain Trichoderma atroviride HN082102.1 isolated from marine habitat alleviates salt stress and diminishes cucumber root rot caused by Fusarium oxysporum

BackgroundSalt stress threaten the growth of plants, and even aggravate plant disease. In this article, salt-tolerant Trichoderma strain was isolated, and its potential to alleviate salt stress and diminish cucumber root rot caused by Fusarium oxysporum was evaluated.ResultsTwenty-seven Trichoderma isolates were isolated from samples of sea muds and algae collected from the South Sea of China. Among these, the isolate HN082102.1 showed the most excellent salt tolerance and antagonistic activity against F. oxysporum causing root rot in cucumber and was identified as T. atroviride. Its antagonism ability may be due to mycoparasitism and inhibition effect of volatile substances. The application of Trichoderma mitigated the adverse effects of salt stress and promoted the growth of cucumber under 100 mM and 200 mM NaCl, especially for the root. When T. atroviride HN082102.1 was applied, root fresh weights increased by 92.55 and 84.86%, respectively, and root dry weights increased by 75.71 and 53.31%, respectively. Meanwhile, the application of HN082102.1 reduced the disease index of cucumber root rot by 63.64 and 71.01% under 100- and 0-mM saline conditions, respectively, indicating that this isolate could inhibit cucumber root rot under salt stress.ConclusionsThis is the first report of salt-tolerant T. atroviride isolated from marine habitat showing antagonistic activity to F. oxysporum, and the results provide evidence for the novel strain T. atroviride HN082102.1 in alleviating salt stress and diminishing cucumber root rot, indicating that T. atroviride strain HN082102.1 can be used as biological control agent in saline alkali land.

Customizing cardboard as a binder for ecofriendly lightweight building materials

Recycling paper and cardboard wastes are becoming important to maintaining a green world. In 2018 manufacturing building materials and their constructions account for 39% of global emissions (13.5 billion tons of CO2). This danger alarm requires immediate action towards seeking for alternatives like traditional materials that have less impact on the environment. Therefore, the current study suggests using new combinations to develop lightweight green building materials. The current research proposes to conduct experimental studies to examine the optimal method for customizing cardboard as a binder for ecofriendly building materials. 17 different mixes were considered in the experimental program; none of these mixes contained cement or consumed any kind of energy. The aim is to develop sustainable lightweight construction materials. Experimental strength results showed a higher strength (up to 7.5 MPa) for some developed substances 22% higher than the strength of traditional mud samples and simultaneously reduction in their weights (dry density 1600 to 1600 kg m−3) in between 13%–16% with superior outdoor durability performance. With these promising results and advantages, the current study can be considered as a primary step towards production of ecofriendly building materials.

Evaluation of the Potential of Periwinkle Shell as pH Enhancer in Water Based Mud

In a quest to provide a direct substitute for foreign chemicals as pH enhancers in drilling mud in the oil and gas industry in Nigeria, the suitability of periwinkle shells, a small gastropod sea snail as a pH enhancer in water-based mud was investigated. The potential evaluation of periwinkle shell as pH enhancer was carried out to determine the effect of periwinkle shell on the pH and mud weight. In this research, the water-based mud sample was formulated using bentonite clay, distilled water (deionized water) with calcined periwinkle shells in varying weight proportions and the pH measurements and mud weight measurements were taken at 25 °C. The results obtained, shows that the periwinkle shell increased the pH value within the range of 64.3% to 92.8% due to incremental addition of 1g to 4g of calcined periwinkle. However, there was little or no increase in the mud weight as the mud weight eventually increased by 0.56%. Consequently, results show that the periwinkle shell has a very high potential for pH enhancement with a reduced potential for mud weight increase.

Effect of organic matter degradation in cohesive sediment: a detailed rheological analysis

PurposeThe presence of organic matter in cohesive sediment results in the formation of clay-organic flocs, which eventually impart complex rheological behavior including shear-thinning, viscoelasticity, thixotropy and two-step yielding to mud. In this study, the influence of microbial degradation of sediment organic matter on the rheological properties of mud samples, having similar densities, was examined.Materials and methodsMud samples were collected from three different locations in the Port of Hamburg, Germany, displaying varying organic matter content. The rheological analysis of fresh and degraded mud samples was performed with the help of several tests including stress ramp-up tests, amplitude sweep tests, frequency sweep tests, time-dependent tests, and structural recovery tests.Results and discussionThe results showed a significant decrease in rheological properties including yield stresses, complex modulus, etc. for degraded mud samples as compared to the fresh mud samples. The slopes of the line, correlating the change (degraded − fresh) in the above-mentioned rheological properties as a function of the same rheological property of the fresh mud, varied within the range of −0.28 to −0.49. The structural recovery tests displayed a better recovery (i.e., stronger system) in mud after the pre-shearing step for the degraded mud samples as compared to the fresh mud samples. The effect of degradation time on the rheological properties of mud samples showed two critical time periods (3 days and 150 days) after which a significant change in rheological properties of mud samples was observed.ConclusionsThis study provided a useful understanding about the influence of organic matter degradation on the rheological properties of mud, which can be used to optimize sediment management strategies in ports and waterways.

Experimental analysis of improving water-based drilling fluid properties by using nanoparticles and poly (AN-co-VP)/zeolite composite

• The influence of various concentrations of chosen nanoparticles containing U-MWCNTs, TiO 2 , ZnO, and F-MWCNTs on water-based drilling fluid was evaluated. The rheological properties such as plastic viscosity, yield point and gel strengths of water-based drilling fluid samples were enhanced by using low concentrations of F-MWCNTs that proved desirable effect in the operational condition of the drilling industry. The most reduction of mud filtrate volume was belonged to F-MWCNTs into drilling fluid composition. The filtration results showed that the poly (AN-co-VP) / zeolite composite with F-MWCNTs could help to prohibit the increase of filtration loss of the mud samples, especially under HPHT environments. The excellence thermal characteristics of poly (AN-co-VP) / zeolite composite and enhancement of mud properties of F-MWCNTs were the best characteristic which could progress the drilling efficiency. In this experimental research, the effect of the poly acrylonitrile-co-N-vinyl pyrrolidone /zeolite composite and four types of hydrophilic and hydrophobic of nanoparticles, namely Zinc oxide, titanium dioxide, untreated multi-walled carbon nanotubes, functionalized multi-walled carbon nanotubes on the rheological and filtrate lost attributes of newly formulated bentonite mud were evaluated. This experimental study compares the drilling fluid properties including different concentrations of nanoparticles to select the most favorite agent through several laboratory tests to generate some engineering guidelines. The different concentrations of nanoparticles (0.0028, 0.0143, 0.028, and 0.143 wt%) were used to investigate the effect on attributes of rheological and mud filtration for bentonite mud. Results of experimental tests indicated that yield point property increases up to 250% with the 0.143 wt% of FMWCNTs in bentonite mud with poly acrylonitrile-co-N-vinyl pyrrolidone/zeolite composite. Also, investigating the effects of higher temperature has shown that an improvement in thermal stability can obtain by using this composite and FMWCNTs in drilling mud rheological properties such as plastic viscosity, yield point, mud filtration volume. Evaluating the effects of using novel formulated water-based mud has shown that it can increase the drilling mud rheological properties and reduce mud filtrate volume and decrease formation damage particularly under the HPHT environment.

Odd palynomorphs (NPPs) from annuli of fern sporangia; Holocene lacustrine and tsunami deposits of the Danish Wadden Sea

Odd palynomorphs are identified in sediments in a shallow core from the Rømø barrier island in the Danish Wadden Sea. The palynomorphs occur in five stratigraphic samples of lacustrine mud, peat and sand. The sand has a chaotic structure and was deposited by a tsunami associated with the Storegga slide in the North Atlantic Ocean, 8150 years ago. The palynomorphs are very common in the lower samples from in situ gyttja and peat and are less common in the overlying sand bed. Reworked lumps of peat occur in the sand and the palynomorphs are therefore also considered reworked into the sand during the tsunami event. The variable morphology of the palynomorphs is considered to represent the ontogeny as well as the specific morphology of fern annuli. The wall tissue of the sporangium is coherent with annulus cells and reveals the fern relationship. The tissue shows a characteristic succession of elongated, rectangular cells in the sporangium wall with stomium and annulus. The palynomorphs are interpreted as parts of annuli from sporangia of leptosporangiate ferns. The modern fern species Hemionitis glabella has a comparable sporangium morphology, and the palynomorphs are considered to come from a fern relative. Hemionitis is cosmopolitan but absent in Europe north of France. This annulus type and the derived palynomorph types have not been described from fossil material before.

Anti-bacteria and toxicity potential of a rare Actinobacterium Pseudonocardia sp. SM1A, isolated from Mangrove Park, West Kalimantan, Indonesia

Abstract. Nofiani R, Rizky, Briliantoro R, Ardiningsih P. 2021. Anti-bacteria and toxicity potential of a rare Actinobacterium Pseudonocardia sp. SM1A, isolated from Mangrove Park, West Kalimantan, Indonesia. Biodiversitas 23: 453-458. This study aimed to identify and evaluate antibacterial and toxicity activities of a rare Actinobacterium isolated from mangrove mud, Mempawah District, West Kalimantan. The mangrove mud sample was inoculated on ISP4 agar dissolved with seawater enriched meropenem (75µg/mL) and nystatin (100 µg/mL) using pour plate procedure and incubated at room temperature until the appearance powdery colony. One of the 2 powdery colonies successfully isolated was SM1A. SM1A was morphologically and biochemically identified to determine its genus and tested antibacterial activities using the cross streak method. SM1A also was cultivated and shaken at room temperature. After 10 days, the culture was extracted using ethyl acetate and then the extract was tested antibacterial activities using a well diffusion method and toxicity using brine shrimp lethality test (BSLT). SM1A was identified as Pseudonocardia sp., then was called Pseudonocardia sp. SM1A. Pseudonocardia sp. SM1A tested anti-bacteria using the cross streak method showed active against Staphylococcus aureus, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Vibrio cholera, and Streptococcus mutants for the ISP4 agar medium and S. typhi, S. mutants, and V. cholera for the ISP1. Pseudonocardia sp. SM1A extract prepared from ISP1 broth medium was active against S. typhi, E. coli, V. cholera, and Streptococcus mutants. In addition, Pseudonocardia sp. SM1A extract cultivated on ISP1 broth medium showed LC50=11.2570 µg/mL based on the BSLT and categorized as moderately toxic level. Pseudonocardia sp. SM1A contained secondary metabolites having high potential as lead compounds for drug discovery.

The Depth-Depended Fungal Diversity and Non-depth-Depended Aroma Profiles of Pit Mud for Strong-Flavor Baijiu.

Microorganisms in pit mud are the essential factor determining the style of strong flavor Baijiu. The spatial distribution characteristics of fungal communities and aroma in the pit mud for strong flavor Baijiu from Xinjiang, China, were investigated using Illumina MiSeq high-throughput sequencing and electronic nose technology. A total of 138 fungal genera affiliated with 10 fungal phyla were identified from 27 pit mud samples; of these, Saccharomycopsis, Aspergillus, and Apiotrichum were the core fungal communities, and Aspergillus and Apiotrichum were the hubs that maintain the structural stability of fungal communities in pit mud. The fungal richness and diversity, as well as aroma of pit mud, showed no significant spatial heterogeneity, but divergences in pit mud at different depths were mainly in pH, total acid, and high abundance fungi. Moisture, NH4+, and lactate were the main physicochemical factors involved in the maintenance of fungal stability and quality in pit mud, whereas pH had only a weak effect on fungi in pit mud. In addition, the fungal communities of pit mud were not significantly associated with the aroma. The results of this study provide a foundation for exploring the functional microorganisms and dissecting the brewing mechanism of strong flavor Baijiu in Xinjiang, and also contributes to the improvement of pit mud quality by bioaugmentation and controlling environmental physicochemical factors.