Phytoremediation: a transgenic perspective in omics era.

Phytoremediation is an environmental safety strategy that might serve as a viable preventative approach to reduce soil contamination in a cost-effective manner. Using plants to remediate pollution from the environment is referred to as phytoremediation. In the past few decades, plants have undergone genetic manipulation to overcome inherent limitations by using genetically modified plants. This review illustrates the eco-friendly process of cleaning the environment using transgenic strategies combined with omics technologies. Herbicides tolerance and phytoremediation abilities have been established in genetically modified plants. Transgenic plants have eliminated the pesticides atrazine and metolachlor from the soil. To expand the application of genetically engineered plants for phytoremediation process, it is essential to test strategies in the field and have contingency planning. Omics techniques were used for understanding various genetic, hormonal, and metabolic pathways responsible for phytoremediation in soil. Transcriptomics and metabolomics provide useful information as resources to understand the mechanisms behind phytoremediation. This review aims to highlight the integration of transgenic strategies and omics technologies to enhance phytoremediation efficiency, emphasizing the need for field testing and comprehensive planning for successful implementation.

Aquincola agrisoli sp. nov., isolated from rhizospheric soil of eggplant and in silico genome mining for the prediction of biosynthetic gene clusters.

A Gram-stain negative, aerobic, rod-shaped, motile and flagellated novel bacterial strain, designated MAHUQ-54T, was isolated from the rhizospheric soil of eggplant. The colonies were observed to be light pink coloured, smooth, spherical and 0.2-0.6 mm in diameter when grown on R2A agar medium for 2 days. MAHUQ-54T was able to grow at 15-40 °C, at pH 5.5-9.0 and in the presence of 0-0.5 % NaCl (w/v). The strain gave positive results for both catalase and oxidase tests. The strain was positive for hydrolysis of l-tyrosine, urea, Tween 20 and Tween 80. On the basis of the results of 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Aquincola and is closely related to Aquincola tertiaricarbonis L10T (98.8 % sequence similarity) and Leptothrix mobilis Feox-1T (98.2 %). MAHUQ-54T has a draft genome size of 5 994 516 bp (60 contigs), annotated with 5348 protein-coding genes, 45 tRNA and 5 rRNA genes. The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between MAHUQ-54T and its closest phylogenetic neighbours were 75.8-83.3 and 20.8-25.3 %, respectively. In silico genome mining revealed that MAHUQ-54T has a significant potential for the production of novel natural products in the future. The genomic DNA G+C content was determined to be 70.4 %. The predominant isoprenoid quinone was ubiquinone-8. The major fatty acids were identified as C16  :  0, summed feature 3 (comprising C16  :  1ω7c and/or C16  :  1ω6c) and summed feature 8 (comprising C18  :  1ω7c and/or C18  :  1ω6c). On the basis of dDDH, ANI value, genotypic analysis, chemotaxonomic and physiological data, strain MAHUQ-54T represents a novel species within the genus Aquincola, for which the name Aquincola agrisoli sp. nov. is proposed, with MAHUQ-54T (=KACC 22001T = CGMCC 1.18515T) as the type strain.

Nocardioides agri sp. nov., isolated from garden soil.

A novel bacterial strain, designated as MAH-18T, was isolated from soil sampled in a flower garden. Cells of strain MAH-18T were Gram-stain-positive, aerobic, motile, and rod-shaped. The colonies were beige in colour, smooth, and spherical when grown on Reasoner's 2A agar medium. Strain MAH-18T grew at 20-40 °C, pH 6.0-8.0, and 0-1.0 % NaCl. Cells were able to hydrolyse aesculin, gelatin, and Tween 20. According to the 16S rRNA gene sequence comparisons, the isolate was determined to be a member of the genus Nocardioides and most closely related to Nocardioides pyridinolyticus OS4T (97.9 %), Nocardioides hankookensis DS-30T (97.9 %), Nocardioides aquiterrae GW-9T (97.6 %), Nocardioides soli mbc-2T (97.5 %), Nocardioides conyzicola HWE 2-02T (97.4 %), and Nocardioides mangrovi GBK3QG-3T (96.3 %). Strain MAH-18T has a draft genome size of 4 788 325 bp (eight contigs), 4572 protein-coding genes, 46 tRNA, and three rRNA genes. The average nucleotide identity and digital DNA-DNA hybridization values between strain MAH-18T and the closest type strains were 81.5-83.4 % and 24.4-25.8 %, respectively. In silico genome mining revealed several biosynthetic gene clusters in the genome of the novel strain MAH-18T. The G+C content of the genomic DNA of strain was 72.2 mol% and the predominant isoprenoid quinone was MK-8 (H4). The main polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, and unknown phospholipids. The major cellular fatty acids were determined to be C16:0 iso and C17 : 1 ω6c. The DNA-DNA hybridization results and phenotypic, genotypic, and chemotaxonomic data demonstrated that strain MAH-18T represents a novel species, for which the name Nocardioides agri sp. nov. is proposed, with MAH-18T as the type strain (=KACC 19744T=CGMCC 1.13656T).

Understanding vermicompost and organic manure interactions: impact on toxic elements, nitrification activity, comammox Nitrospira inopinata, and archaea/bacteria.

Vermicompost is a substantial source of nutrients, promotes soil fertility, and maintains or increases soil organic matter levels. Potentially toxic elements (PTEs) in vermicompost impact on nitrification activity. However, it is yet unknown how vermicompost affects nitrifying bacteria and archaea, comammox Nitrospira inopinata (complete ammonia oxidizers), net nitrification rates (NNRs), and PTEs. The effects of vermicompost application on NNRs, potential nitrification rates (NPs), PTEs, and the abundances of comammox N. inopinata bacteria, nitrite-oxidizing bacteria (NOB), and ammonia-oxidizing bacteria (AOB)/archaea (AOA) were studied. NNRs and NPs were significantly higher (p < 0.05) in fresh cow-dung vermicompost (stored for 40 days) as compared with other organic manure. The level of PTEs (Cu2+, Fe2+, Pb2+, Cd2+, and Zn2+) was significantly lower (p < 0.05) in vermicompost as compared with compost of waste material with Trichoderma and cow dung. Comammox N. inopinata, NOB, AOB, and AOA were significantly higher (p < 0.05) in stored cow-dung vermicompost (more than 1 year) as compared with other organic manure. The results of the scatterplot matrix analysis suggested that Fe2+, total nitrogen (TN), soil organic carbon (SOC), and total carbon (TC) were linearly correlated (p < 0.001) with NNRs and NPs in vermicompost and organic manure. Similarly, comammox N. inopinata bacteria, NOB, AOB, and AOA were linearly correlated (p < 0.001) with NNR and NP. These results indicated that vermicompost promoted nitrification activity by increasing microbial diversity and abundance, supplying nutrients and organic matter for microbial growth, and facilitating complex microbial interactions. It may be concluded that the influence of vermicompost, which played a great role in PTE concentration reduction, increased chemical, and biological properties, increased the growth rate of nitrifying bacteria/archaea and the nitrogen cycle.

Isolation and characterization of Pinibacter soli sp. nov., and in silico genome mining of Pinibacter for biosynthetic gene cluster prediction.

A Gram-stain-negative, aerobic, rod-shaped, non-motile and non-flagellated novel bacterial strain, designated MAH-24T, was isolated from the rhizospheric soil of a pine garden. The colonies were observed to be orange-coloured, smooth, spherical and 0.4-0.8 mm in diameter when grown on Reasoner's 2A agar medium for 2 days. Strain MAH-24T was found to be able to grow at 10-35 °C, at pH 6.0-9.0 and in the presence of 0-1.0 % NaCl (w/v). The strain was found to be positive for the catalase and oxidase tests. The strain was positive for hydrolysis of aesculin and l-tyrosine. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Pinibacter and to be closely related to Pinibacter aurantiacus MAH-26T (99.2 % sequence similarity). The novel strain MAH-24T has a draft genome size of 5 918 133 bp (13 contigs), annotated with 4613 protein-coding genes, 47 tRNA and three rRNA genes. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MAH-24T and the closest type strain P. aurantiacus MAH-26T were in the range of 85.3 and 29.9 %, respectively. In silico genome mining revealed that both novel strain MAH-24T and P. aurantiacus MAH-26T have a significant potential for the production of novel natural products in the future. The genomic DNA G+C content was determined to be 41.0 mol%. The predominant isoprenoid quinone was menaquinone-7. The major fatty acids were identified as C15:0 iso, C15:1 iso G and C17:0 iso 3OH. On the basis of dDDH, ANI, genotypic, chemotaxonomic and physiological data, strain MAH-24T represents a novel species within the genus Pinibacter, for which the name Pinibacter soli sp. nov. is proposed, with MAH-24T (=KACC 19747T=CGMCC 1.13659T) as the type strain.

Massilia agrisoli sp. nov., isolated from rhizospheric soil of banana.

A Gram-stain-negative, aerobic, short rod-shaped and motile novel bacterial strain, designated MAHUQ-52T, was isolated from the rhizospheric soil of a banana plant. Colonies grew at 10-35 °C (optimum, 28 °C), pH 6.0-9.5 (optimum, pH 7.0-7.5), and in the presence of 0-1.0 % NaCl (optimum 0 %). The strain was positive for catalase and oxidase tests, as well as hydrolysis of gelatin, casein, starch and Tween 20. Based on the results of phylogenetic analysis using 16S rRNA gene and genome sequences, strain MAHUQ-52T clustered together within the genus Massilia. Strain MAHUQ-52T was closely related to Massilia soli R798T (98.6 %) and Massilia polaris RP-1-19T (98.3 %). The novel strain MAHUQ-52T has a draft genome size of 4 677 454 bp (25 contigs), annotated with 4193 protein-coding genes, 64 tRNA and 19 rRNA genes. The genomic DNA G+C content was 63.0 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MAHUQ-52T and closely related type strains were ≤88.4 and 35.8 %, respectively. The only respiratory quinone was ubiquinone-8. The major fatty acids were identified as C16 : 0 and summed feature 3 (C15 : 0 iso 2-OH and/or C16 : 1 ω7c). Strain MAHUQ-52T contained phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol as the major polar lipids. On the basis of dDDH and ANI values, as well as genotypic, chemotaxonomic and physiological data, strain MAHUQ-52T represents a novel species within the genus Massilia, for which the name Massilia agrisoli sp. nov. is proposed, with MAHUQ-52T (=KACC 21999T=CGMCC 1.18577T) as the type strain.

Pseudomonas oryzagri sp. nov., isolated from a rice field soil.

A Gram-stain-negative, aerobic, rod-shaped and non-motile novel bacterial strain, designated MAHUQ-58T, was isolated from soil sample of a rice field. The colonies were observed to be light pink-coloured, smooth, spherical and 0.6-1.0 mm in diameter when grown on nutrient agar (NA) medium for 2 days. Strain MAHUQ-58T was found to be able to grow at 15-40 °C, at pH 5.5-10.0 and with 0-1.0 % NaCl (w/v). Cell growth occurred on tryptone soya agar, Luria-Bertani agar, NA, MacConkey agar and Reasoner's 2A agar. The strain was found to be positive for both oxidase and catalase tests. The strain was positive for hydrolysis of Tween 20 and l-tyrosine. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Pseudomonas and to be closely related to Pseudomonas oryzae WM-3T (98.9 % similarity), Pseudomonas linyingensis LYBRD3-7T (97.7 %), Pseudomonas sagittaria JCM 18195 T (97.6 %) and Pseudomonas guangdongensis SgZ-6T (97.2 %). The novel strain MAHUQ-58T has a draft genome size of 4 536 129 bp (46 contigs), annotated with 4064 protein-coding genes, 60 tRNA genes and four rRNA genes. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MAHUQ-58T and four closely related type strains were in the range of 85.5-89.5 % and 29.5-38.0 %, respectively. The genomic DNA G+C content was determined to be 67.0 mol%. The predominant isoprenoid quinone was ubiquinone 9. The major fatty acids were identified as C16:0, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c). On the basis of dDDH and ANI values, genotypic results, and chemotaxonomic and physiological data, strain MAHUQ-58T represents a novel species within the genus Pseudomonas, for which the name Pseudomonas oryzagri sp. nov. is proposed, with MAHUQ-58T (=KACC 22005T=CGMCC 1.18518T) as the type strain.

Inhibition of Aldose Reductase by Ginsenoside Derivatives via a Specific Structure Activity Relationship with Kinetics Mechanism and Molecular Docking Study.

This present work is designed to evaluate the anti-diabetic potential of 22 ginsenosides via the inhibition against rat lens aldose reductase (RLAR), and human recombinant aldose reductase (HRAR), using DL-glyceraldehyde as a substrate. Among the ginsenosides tested, ginsenoside Rh2, (20S) ginsenoside Rg3, (20R) ginsenoside Rg3, and ginsenoside Rh1 inhibited RLAR significantly, with IC50 values of 0.67, 1.25, 4.28, and 7.28 µM, respectively. Moreover, protopanaxadiol, protopanaxatriol, compound K, and ginsenoside Rh1 were potent inhibitors of HRAR, with IC50 values of 0.36, 1.43, 2.23, and 4.66 µM, respectively. The relationship of structure-activity exposed that the existence of hydroxyl groups, linkages, and their stereo-structure, as well as the sugar moieties of the ginsenoside skeleton, represented a significant role in the inhibition of HRAR and RLAR. Additional, various modes of ginsenoside inhibition and molecular docking simulation indicated negative binding energies. It was also indicated that it has a strong capacity and high affinity to bind the active sites of enzymes. Further, active ginsenosides suppressed sorbitol accumulation in rat lenses under high-glucose conditions, demonstrating their potential to prevent sorbitol accumulation ex vivo. The findings of the present study suggest the potential of ginsenoside derivatives for use in the development of therapeutic or preventive agents for diabetic complications.

Paenibacillus roseus sp. nov., a ginsenoside-transforming bacterium isolated from forest soil.

A novel, pink-pigmented, Gram-stain-positive, aerobic, motile, rod-shaped and ginsenoside-converting bacterium, designated strain MAHUQ-46T, was isolated from soil of a forest. Strain MAHUQ-46T grew in the pH range 6.0-9.0 (optimum, 7.5), at temperatures between 10 and 37 °C (optimum, 30 °C) and at 0-3% (w/v) NaCl (optimum, 0.5%). 16S rRNA gene sequence analysis showed that strain MAHUQ-46T was closely related to Paenibacillus pinihumi S23T (97.3% similarity), followed by Paenibacillus elymi KUDC6143T (96.7%). The draft genome of strain MAHUQ-46T had a total length of 5,367,904 base pairs. A total of 4,857 genes were identified, in which 4,629 were protein-coding genes and 137 were RNA genes. The genome annotation of MAHUQ-46T showed 172 carbohydrate genes, some of them may be responsible for the biosynthesis of ginsenoside Rd from major ginsenoside Rb1. The DNA G + C content was 48.4 mol% and the major quinone was MK-7. Main fatty acids of strain MAHUQ-46T were C15: 0 anteiso, C16: 0 and C17: 0 anteiso. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidyl-N-methylethanolamine, two unidentified aminophospholipids and five unidentified phospholipids. Diagnostic diamino acid of peptidoglycan was meso-diaminopimelic acid. The novel strain MAHUQ-46T was able to rapidly synthesize ginsenoside Rd from major ginsenoside Rb1. The synthesized ginsenoside was confirmed by TLC and HPLC analysis. According to the phenotypic, genetic and chemotaxonomic evidence, strain MAHUQ-46T was clearly distinguishable from validly published species of genus Paenibacillus and should, therefore, be categorized as a novel species for which the name Paenibacillus roseus sp. nov. is proposed. The type strain is MAHUQ-46T (= KACC 21242T = CGMCC 1.17353T).

Niastella soli sp. nov., isolated from rhizospheric soil of a persimmon tree.

A Gram-stain-negative, aerobic, motile and rod-shaped novel bacterial strain, designated MAH-29T, was isolated from rhizospheric soil of a persimmon tree. The colonies were light pink coloured, smooth, spherical and 0.1-0.8 mm in diameter when grown on Reasoner's 2A (R2A) agar for 2 days. Strain MAH-29T was able to grow at 20-37 °C, at pH 5.0-8.5 and at 0-2.0 % NaCl. Cell growth occurred on nutrient agar and R2A agar. The strain was positive in both oxidase and catalase tests. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Niastella and was closely related to Niastella vici DJ57T (97.7 % similarity), Niastella koreensis GR20-10T (97.1 %) and Niastella yeongjuensis GR20-13T (97.0 %). Strain MAH-29T has a draft genome size of 8 876 333 bp (31 contigs), annotated with 6920 protein-coding genes, 61 tRNA and four rRNA genes. The average nucleotide identity and digital DNA-DNA hybridization values between strain MAH-29T and three closely related type strains were in the range of 78.2-83.2 % and 22.1-27.0 %, respectively. The genomic DNA G+C content was 43.8 mol%. The predominant isoprenoid quinone was menaquinone 7. The major fatty acids were identified as iso-C15:0, iso-C15:1 G and iso-C17:0 3OH. On the basis of DNA-DNA hybridization results, genotypic analysis and chemotaxonomic and physiological data, strain MAH-29T represents a novel species within the genus Niastella, for which the name Niastella soli sp. nov. is proposed, with MAH-29T (=KACC 19969T=CGMCC 1.16606T) as the type strain.

Pinibacter aurantiacus gen. nov., sp. nov., isolated from rhizospheric soil of a pine tree.

A Gram-stain-negative, aerobic and rod-shaped novel bacterial strain, designated MAH-26T, was isolated from rhizospheric soil of a pine tree. The colonies were orange coloured, smooth, spherical and 0.7-1.8 mm in diameter when grown on Reasoner's 2A (R2A) agar for 2 days. Strain MAH-26T was able to grow at 10-40 °C, at pH 6.0-9.0 and with 0-1.0 % NaCl. Cell growth occurred on nutrient agar, R2A agar, tryptone soya agar and Luria-Bertani agar. The strain gave positive results in oxidase and catalase tests. Strain MAH-26T was closely related to Flavihumibacter sediminis CJ663T and Parasegetibacter terrae SGM2-10T with a low 16S rRNA gene sequence similarity (92.8 and 92.9 %, respectively) and phylogenetic analysis indicated that the strain formed a distinct phylogenetic lineage from the members of the closely related genera of the family Chitinophagaceae. Strain MAH-26T has a draft genome size of 6 857 405 bp, annotated with 5173 protein-coding genes, 50 tRNA and two rRNA genes. The genomic DNA G+C content was 41.5 mol%. The predominant isoprenoid quinone was menaquinone 7. The major fatty acids were identified as iso-C15:0, iso-C15:1 G and iso-C17:0 3OH. On the basis of phylogenetic inference and phenotypic, chemotaxonomic and molecular properties, strain MAH-26T represents a novel species of a novel genus of the family Chitinophagaceae, for which the name Pinibacter aurantiacus gen. nov., sp. nov. is proposed. The type strain of Pinibacter aurantiacus is MAH-26T (=KACC 19749T=CGMCC 1.13701T).

Effect of Pesticides and Chemical Fertilizers on the Nitrogen Cycle and Functional Microbial Communities in Paddy Soils: Bangladesh Perspective.

The concept of the Nitrogen (N) cycle has been modified over the years based on certain new pathways, including comammox, anammox, and DNRA (dissimilatory nitrate reduction to ammonium). Comammox, nitrification, anammox, denitrification, DNRA, and nitrogen fixation pathways play key roles in the N cycle in paddy soils. Pesticides and chemical fertilizers' effects on the N cycle in paddy soils together with the possible manifestation of these newly discovery pathways are the focus of this review. Both chemical fertilizers and pesticides' overuse affect nitrifying archaea/bacteria and denitrifying and anammox bacteria, while heavy metals affect the nitrification rates in paddy soils. To add extra value to this study, we quantified the comammox amoA single copy gene from the Nitrospira strain 'Nitrospira inopinata'. This review will help researchers access the latest information on the N cycle, particularly in the light of the most recent discoveries.

Effect of Manure Application on Net Nitrification Rates, Heavy Metal Concentrations and Nitrifying Archaea/Bacteria in Soils.

In this study, we determined the effect of manure application on net nitrification rates (NNRs), heavy metal concentrations (HMCs), and abundance of ammonia-oxidizing archaea (AOA)/bacteria (AOB), and nitrite-oxidizing bacteria (NOB) in soil. HMCs were measured by atomic absorption spectroscopy. Abundance of AOA, AOB, and NOB was enumerated by q-PCR. NNRs ranged from 2.8 to 14.7 mg kg-1 h-1 and were significantly (p < 0.05) increased in manure soils as compared to control soils. NNRs were affected by pH 7 and temperature 30°C. Cd, Fe and Pb concentrations were classified as excessively polluted, moderate contamination and slight pollution, respectively, in the manure soils. NNRs and concentrations of Fe and Pb were significantly (p < 0.00) positive correlated, but Cu and Cd were significantly (p < 0.00) negative correlated with NNRs. Application of manure significantly (p < 0.05) increased HMCs (Fe, Cu, and Pb), which have indirect and direct effects on NNRs and nitrifying bacteria.

Effect of Long-Term Pesticides and Chemical Fertilizers Application on the Microbial Community Specifically Anammox and Denitrifying Bacteria in Rice Field Soil of Jhenaidah and Kushtia District, Bangladesh.

In this study, we investigated the effect of long-term pesticides and chemical fertilizers application on the microbial communities specifically anammox and denitrification bacteria in rice field soils. The abundances of microbial communities (16S rDNA), anammox (hszB), and denitrification (narG, nirK, nirS, and nosZ) genes were quantified by q-PCR. 10 pesticides (5 insecticides, 3 fungicides and 2 herbicides) and chemical fertilizers urea, potassium, phosphate, DAP (di-ammonium phosphate), gypsum, and boric acid were used by local farmers. Nitrate, SOC (ammonia, soil organic carbon), N and C content significantly (p < 0.05) decreased in the rice field soils as compared to the upland soils. Abundance of 16S rDNA, hszB, narG, nirK, nirS, and nosZ genes significantly (p < 0.05) decreased in the rice field soils and positively correlated with chemical properties of soils. Our results provide useful information and further maintenance should be instilled to the potential of chemical and biological factors decreased in rice field soils.

Prevalence of diabetes and prediabetes and their risk factors among Bangladeshi adults: a nationwide survey.

OBJECTIVE: To estimate the prevalence of diabetes and prediabetes in Bangladesh using national survey data and to identify risk factors. METHODS: Sociodemographic and anthropometric data and data on blood pressure and blood glucose levels were obtained for 7541 adults aged 35 years or more from the biomarker sample of the 2011 Bangladesh Demographic and Health Survey (DHS), which was a nationally representative survey with a stratified, multistage, cluster sampling design. Risk factors for diabetes and prediabetes were identified using multilevel logistic regression models, with adjustment for clustering within households and communities. FINDINGS: The overall age-adjusted prevalence of diabetes and prediabetes was 9.7% and 22.4%, respectively. Among urban residents, the age-adjusted prevalence of diabetes was 15.2% compared with 8.3% among rural residents. In total, 56.0% of diabetics were not aware they had the condition and only 39.5% were receiving treatment regularly. The likelihood of diabetes in individuals aged 55 to 59 years was almost double that in those aged 35 to 39 years. Study participants from the richest households were more likely to have diabetes than those from the poorest. In addition, the likelihood of diabetes was also significantly associated with educational level, body weight and the presence of hypertension. The prevalence of diabetes varied significantly with region of residence. CONCLUSION: Almost one in ten adults in Bangladesh was found to have diabetes, which has recently become a major public health issue. Urgent action is needed to counter the rise in diabetes through better detection, awareness, prevention and treatment.

Color, antioxidant and nutritional composition of dehydrated country bean (Lablab purpureus) seeds using solar drying techniques and pretreatments in Bangladesh.

The country bean (Lablab purpureus), is a significant contributor of dietary protein and other essential components in human nutrition. Because of its elevated moisture content, it is susceptible to rapid decay, leading to losses after harvesting. The utilization of solar drying has attracted significant attention as a tactic to minimize nutrient depletion in dried goods and enhance their longevity. This study employed four solar drying techniques, namely long chimney, short chimney, box solar drying and open sun drying, along with pretreatments such as potassium metabisulfite, potassium-sodium tartrate, citric acid and ascorbic acid. The objective was to determine an effective solar drying method, combined with pretreatment, that can maintain the color and nutritional qualities of dried country bean seeds. The treatment combinations were organized in a factorial randomized complete block design (RCBD) with three replications. The data were subjected to a two-way analysis of variance (ANOVA) and a Duncan Multiple Range Test (DMRT) was conducted at a significance level of 5 % (p < 0.05). Results revealed that box solar dryer having the highest drying efficiency, retained the highest ß-carotene (82.94 %), vitamin C (90.15 %), protein (96.48 %), fat (11.63 %), and ash (90.50 %) with maximum DPPH radical scavenging activity (lowest IC50 209.49 µg/ml) compared to other driers. Besides, country bean seeds have noteworthy proximate compositions, antioxidant activity, and bioactive components treated with 1 % potassium metabisulfite. Furthermore, the country bean seeds dehydrated in box solar dryer after 1 % potassium metabisulfite treatment received the highest acceptance score on the five-point Hedonic scale (4.83-4.89 out of 5.00) and color appearance and the similar trend was further supported by principal component analysis. Thus, it can be inferred that using a box solar dryer with a 1 % potassium metabisulfite pretreatment is a feasible method for preserving the color and nutritional value of country bean seeds and reducing postharvest losses.

Colour, nutritional composition and antioxidant properties of dehydrated carrot (Daucus carota var. sativus) using solar drying techniques and pretreatments.

Carrot is a seasonal perishable tuberous root vegetable which presents a preservation challenge owing to its elevated moisture content. Recently, carrot processing has received more attention because of its many health-promoting qualities and the reduction of postharvest losses in a cost-effective safe way. This study was designed to sort out the effective solar drying technique including pre-treatment that would retain the color and quality characteristics of dehydrated carrot. Carrot slices were subjected to dry using open sun drying (D1), solar drying long chimney (D2), solar drying short chimney (D3) and box solar drying (D4) techniques with the pretreatments of ascorbic acid 1 % (C3), citric acid 5 % (C4), potassium metabisulfite 1 % (C5) and potassium sodium tartrate 0.3 % (C6) before drying. Drying characteristics, nutritional attributes, phytochemicals and antioxidant of the dehydrated carrot samples were compared with the fresh sample and untreated (control) sample. Results showed that D4 was a good drying method to preserve nutritional quality with good appearance. Among the pretreatments, C5 and C4 resulted improved nutritional quality retention, enhanced visual acceptability and enriched antioxidant activities. PCA (Principal Component Analysis) and correlation matrix revealed that D4 with C5 retained the maximum amount of vitamin, minerals, total phenolic content, antioxidant and admirable dehydrated carrot color by inactivating enzymatic reaction. Therefore, box solar drying with potassium metabisulfite pretreatment would be very promising for functional carrot drying retaining acceptable color and nutrition composition.

Numerical and analytical solutions of new Blasius equation for turbulent flow.

The Blasius equation for laminar flow comes from the Prandtl boundary layer equations. In this article, we establish a new and generic Blasius equation for turbulent flow derived from the turbulent boundary layer equation that can be used for turbulent as well as laminar flow. The analytical and numerical solutions have been investigated under specific conditions to the developed new Blasius equation. The analytical and numerical results have been compared through tables and graphs to validate the established model. In fluid dynamics, analytical solutions to complicated systems are tedious and time-consuming. Changing one or more constraints can introduce new challenges. In this case, symbolic computation software provides an easier and more flexible solution for fluid dynamical systems, even if boundary conditions are adjusted to explain reality. Therefore, the MATLAB code is used to investigate the new third-order Blasius equation. The comparison and graphical representations demonstrate that the achieved results are encouraging.

Green Synthesis and Potential Antibacterial Applications of Bioactive Silver Nanoparticles: A Review.

Green synthesis of silver nanoparticles (AgNPs) using biological resources is the most facile, economical, rapid, and environmentally friendly method that mitigates the drawbacks of chemical and physical methods. Various biological resources such as plants and their different parts, bacteria, fungi, algae, etc. could be utilized for the green synthesis of bioactive AgNPs. In recent years, several green approaches for non-toxic, rapid, and facile synthesis of AgNPs using biological resources have been reported. Plant extract contains various biomolecules, including flavonoids, terpenoids, alkaloids, phenolic compounds, and vitamins that act as reducing and capping agents during the biosynthesis process. Similarly, microorganisms produce different primary and secondary metabolites that play a crucial role as reducing and capping agents during synthesis. Biosynthesized AgNPs have gained significant attention from the researchers because of their potential applications in different fields of biomedical science. The widest application of AgNPs is their bactericidal activity. Due to the emergence of multidrug-resistant microorganisms, researchers are exploring the therapeutic abilities of AgNPs as potential antibacterial agents. Already, various reports have suggested that biosynthesized AgNPs have exhibited significant antibacterial action against numerous human pathogens. Because of their small size and large surface area, AgNPs have the ability to easily penetrate bacterial cell walls, damage cell membranes, produce reactive oxygen species, and interfere with DNA replication as well as protein synthesis, and result in cell death. This paper provides an overview of the green, facile, and rapid synthesis of AgNPs using biological resources and antibacterial use of biosynthesized AgNPs, highlighting their antibacterial mechanisms.

Effect of pesticides on nitrification activity and its interaction with chemical fertilizer and manure in long-term paddy soils.

Effect of pesticides on nitrification activity and its interaction among heavy metal concentrations (HMCs), antibiotic resistance genes (ARGs), and ammonia monooxygenase (amoA) genes of long-term paddy soils is little known. The aim was to study the effect of pesticides on net nitrification rate (NR), potential nitrification rate (NP), HMCs, ARGs (sulI, sulII, tetO, and tetQ), and amoA (amoA-AOA, amoA-AOB, and amoA-NOB) genes in long-term treated paddy soils. NR and NP were significantly decreased (p < 0.05), whereas HMCs (Pb2+, Cu2+, Zn2+, and Fe3+) were a significantly increased (p < 0.05) in chemical fertilizer with pesticide treated paddy soils as compared with chemical fertilizer treated paddy soils. The scatter plot matrix indicated that total carbon (TC), soil organic carbon (SOC), total nitrogen (TN), and Fe were linearly correlated with NR and NP in long-term treated paddy soils. ARGs and amoA genes were significantly decreased (p < 0.05) in chemical fertilizer and manure with pesticide treated paddy soils. Overall, the result indicated the response of pesticide and their combination of manure with pesticide interaction present in long-term paddy soils, which will play a great role in the control uses of pesticides, manure, and chemical fertilizers in paddy soils and protect the nitrogen cycle as well as environment.