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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Sara Centeno-Leija ◽  
Laura Espinosa-Barrera ◽  
Beatriz Velazquez-Cruz ◽  
Yair Cárdenas-Conejo ◽  
Raúl Virgen-Ortíz ◽  
...  

AbstractCarbohydrate metabolism via cyclodextrins (CM-CD) is an uncommon starch-converting pathway that thoroughly depends on extracellular cyclomaltodextrin glucanotransferases (CGTases) to transform the surrounding starch substrate to α-(1,4)-linked oligosaccharides and cyclodextrins (CDs). The CM-CD pathway has emerged as a convenient microbial adaptation to thrive under extreme temperatures, as CDs are functional amphipathic toroids with higher heat-resistant values than linear dextrins. Nevertheless, although the CM-CD pathway has been described in a few mesophilic bacteria and archaea, it remains obscure in extremely thermophilic prokaryotes (Topt ≥ 70 °C). Here, a new monophyletic group of CGTases with an exceptional three-domain ABC architecture was detected by (meta)genome mining of extremely thermophilic Thermoanaerobacterales living in a wide variety of hot starch-poor environments on Earth. Functional studies of a representative member, CldA, showed a maximum activity in a thermoacidophilic range (pH 4.0 and 80 °C) with remarkable product diversification that yielded a mixture of α:β:γ-CDs (34:62:4) from soluble starch, as well as G3–G7 linear dextrins and fermentable sugars as the primary products. Together, comparative genomics and predictive functional analysis, combined with data of the functionally characterized key proteins of the gene clusters encoding CGTases, revealed the CM-CD pathway in Thermoanaerobacterales and showed that it is involved in the synthesis, transportation, degradation, and metabolic assimilation of CDs.


Author(s):  
Shanmugam Abirami ◽  
Sudalaimani Dinesh Kumar ◽  
Athiappan Murugan

Synthetic dyes are hazardous to the environment and humans due to their toxic and recalcitrant nature. Hence, the present study attempts to produce eco-friendly dye from the sago industrial waste using S. marcescens SS1. The dye produced by the bacterial bioconversion of sago was characterized by GC-MS and obtained 13.423 acquisition time, which is similar to the standard prodigiosin. The effects of the dyeing parameters were optimized for Jute fabric using tannic acid as a pre mordant, the maximum uptake of dye was observed at 80 °C, pH 7, 60 mins with the K/S of 6.6. The minimum K/S value of 3.9 was observed at 65 °C, pH 3 in 45 min. Better colour fastness was observed in prodigiosin with mordant compared to without mordant. The antimicrobial activity of dyed fabric was tested against a few pathogenic bacteria and it showed maximum activity against P. aeruginosa. The dye extracted from S. marcescens SS1 prodigiosin was found to be an effective dyeing agent and also pose antimicrobial properties.


Author(s):  
Shivani Kushwaha

Abstract: Nanotechnology is a rising field of science and technology that deals with the particles having size in the range of 1 to 100 nm. Copper oxide nanoparticles has many properties like antifungal activity, antibacterial activity, optical properties, conductive properties, etc. Due to its demand of diversified use, copper oxide nanoparticles were fabricated using ecofriendly and non-toxic Annona muricata stem extract. The extract with copper sulphate pentahydrate showed gradual change in the colour of the extract from brown to green which indicates the CuO nanoparticles synthesis. The fabrication is followed by characterization of CuO nanoparticles using UV-vis spectroscope, FTIR, XRD and SEM. The characterization showed roughly spherical shaped nanoparticles in the range of 100nm with high crystalline monoclinic phase. FTIR absorption spectra conclude that the compounds attached with copper oxide nanoparticles could be polyphenols with aromatic ring. The CuO nanoparticles exhibited antibacterial activity; it showed the maximum activity against E.coli (18 mm). Keywords: Annona muricata, copper sulphate pentahydrate, FTIR, nanomaterials, SEM, XRD.


2021 ◽  
Vol 4 ◽  
pp. 73-77
Author(s):  
Pooja Latti ◽  
R. Subramaniam ◽  
G. M. Prashant

Objectives: To evaluate the antibacterial activity of black pepper, Indian bay leaf, cinnamon, and cumin against Streptococcus mutans and Lactobacillus acidophilus in-vitro and to determine their minimum inhibitory concentration (MIC). Materials and Methods: The spices (cinnamon, cumin, Indian bay leaf, and black pepper) were obtained from local market, were dried and powdered. Solvent extracts were prepared with methanol by maceration, followed by filtration and evaporation. The antimicrobial activity was assessed using cup plate diffusion method, followed by determination of MIC of the extracts. Statistical analysis was performed using one-way analysis of variance and Tukey’s post hoc test was used for pairwise comparison. P < 0.05 was considered statistically significant. Results: All the four extracts showed significant antimicrobial activity. Cinnamon demonstrated maximum activity against S. mutans (zone of inhibition of 18.1 mm ± 0.30) and L. acidophilus (zone of inhibition of 17.9 mm ± 0.44) with the least MIC against the organisms (<0.05 mg/ml). Conclusion: All the spice extracts tested demonstrated significant antibacterial activity against S. mutans and L. acidophilus. On comparison of the antibacterial activities of all the four extracts, cinnamon extract emerged as the potent agent.


2021 ◽  
Author(s):  
Nadia Dawoud ◽  
Hamada El-Gendi ◽  
Abdallah Abdallah ◽  
Esmail M. El-Fakharany ◽  
Doaa Lotfy

Abstract The current study was directed toward developing a new series of fused heterocycles incorporating an indazolylthiazole moiety. The newly synthesized compounds were characterized through elemental analysis and spectral data (IR, 1H-NMR, 13C-NMR, and mass spectrometry). The cytotoxic effect of the newly synthesized compounds was evaluated against normal human cells (HFB-4) and cancer cell lines (HepG-2 and Caco-2). Among the synthesized compounds, derivatives 4, and 6 revealed significant selective antitumor activity, in a dose-dependent manner, against both HepG-2 and Caco-2 cell lines, with a lower risk toward HFB-4 cells (normal cells). Derivative 8 revealed the maximum antitumor activity toward both tumor cell lines, with an SI value of about approximately 26 and an IC50 value of approximately 5.9 µg/ml. The effect of these derivatives (8, 4, and 6) on the expression of 5 tumor regulating genes was studied through quantitative real-time PCR, where their interaction with these genes was simulated through a molecular docking study. Furthermore, the antimicrobial activity results revealed that compounds 2, 7, 8, and 9 have potential antimicrobial activity, with maximum broad spectrum activity through compound 3 against the three tested pathogens: Streptococcus mutans, Pseudomonas aeruginosa, and Candida albicans. The newly prepared compounds also revealed antibiofilm formation activity with maximum activity against Streptococcus mutans, Pseudomonas aeruginosa, and Candida albicans.


2021 ◽  
Author(s):  
Anurag Maurya ◽  
Eepsita Priyadarshini ◽  
Paulraj Rajamani

Abstract Fig (Ficus carica L.; Hindi: Anjeer) is one of the the earliest domesticated fruit. Present study investigates its antiproliferative activity against breast cancer (MDA MB-468) cells. Dry figs were mascerated in sixteen solvent-combinations of varying polartiy and extracts were assessed for antiproliferative activity in vitro. Extracts of moderatly polar solvents, particularly 80% aqueous-methanol extract showed maximum activity (IC50 = 17.9 mg IDF/ml). Antiproliferative efficacy of extracts was supported by respective total phenolic content (41-236 mg GAE/100g) and various antioxidant capacities; ABTS (14-354 µM TE/g), DPPH (18-460 µM TE/g), FRAP (28.7-66.5 µM FeSO4 equivalents/g), ORAC (7.9-32.8 µM TE/g), and superoxide radical scavenging activity. Flow cytometry analysis revealed that extracts of lower IC50 induce more cell death. Phenolic compounds (cyanidin 3-O-glucoside, quercetin 3-β-glucoside, rutin, trans-cinnamic acid, ellagic acid and ferulic acid) were analysed by UPLC-PDA technique and their concentrations in extracts were found to be negatively correlated with respective IC50 values. The negative correlation suggests the involvement of phenolics in fig’s antiproliferative mechanism. Therefore, the study advocates fig as a dietary component having anticancer potential.


Author(s):  
Elzbieta Malarczyk

The allosteric protein of horseradish peroxidase (HRP) shows two main types of activity, peroxidase and oxidase, depending on the kind of low molecular effectors. The effects of very low doses of phenol, prepared by successive dilutions in water or in 75% ethanol, on initial HRP activity in oxidation of o-dianisidine or luminol were tested in a systematic manner by colorimetric and luminometric methods. Results showed that phenol dilutions, including those below Avogadro’s number, could activate or inhibit HRP in peroxidase and oxidase type reactions with a sinusoidal pattern. Km values for the studied substrates changed parallel to HRP peroxidase/oxidase activity and the maximum activity in the peroxidase reaction corresponded to the minimum activity in the oxidase reaction and vice versa. The effect also depended on the type of dilutor. The observations of the peroxidase/oxidase oscillations in the sinusoidal pattern of HRP activity, dependent on the rate of phenol dissolution and the time of preincubation, point out to the conclusion that HRP might be a good model for high dilutions research. The experiments provide strong evidence that horseradish peroxidase (HRP) is a very sensitive detector of subtle changes in the concentration of phenol used as a cofactor in the peroxidase/oxidase reaction. Keywords: HR-peroxidase, peroxidase-oxidase, phenol, hormesis, homeopathy, high dilutions.   Mudanças cinéticas na atividade da HR-peroxidade induzidas por doses muito baixas de fenol Resumo A proteína alostérica da peroxidase do rabano (HRP) mostra dois tipos principais de atividade, peroxidase e oxidase, de acordo com o tipo de efetores de baixa molecularidade. Os efeitos de doses muito baixas de fenol, preparadas através de diluições sucessivas em água ou etanol 75% na atividade inicial da HRP sobre a oxidação da o-dianisidina ou luminol for testados de modo sistemático através de métodos colorimétricos e luminométricos. Os resultados mostram que as diluições de fenol, incluindo aquelas por baixo do número de Avogadro, foram capazes de ativar ou inibir a HRP em reações de tipo peroxidade e oxidase com um padrão sinusoidal. os valores Km dos substratos estudados variaram paralelamente à atividade peroxidase/oxidase da HRP; a atividade máxima da reação peroxidase correspondeu à atividade mínima na reação oxidase e vice-versa. O efeito também se mostrou dependente do tipo do solvente. A observação das oscilações sinusoidais na atividade da HRP, dependentes da taxa de dissolução do fenol e do tempo de pré-incubação, permitem concluir que a HRP pode ser um bom modelo na pesquisa das altas diluições. Os experimentos oferecem fortes evidéncias a favor da HRP como detector muito sensível de mudanças mínimas na concentração do fenol, utilizado como cofator na reação peroxidase/oxigenase. Palavras-chave: HR-peroxidase, peroxidase-oxidase, fenol, hormese, homeopatia, altas diluições.   Cambios cinéticos en la actividad de la HR-peroxidasa inducidos por dosis muy bajas de fenol Resumen La proteína alostérica de la peroxidasa del rábano (HRP) muestra dos tipos principales de actividad, peroxidasa y oxidasa, dependiendo del tipo de efectores de baja molecularidade. Los efectos de doses muy bajas de fenol, preparadas mediante diluciones sucesivas en agua o etanol al 75% sobre la actividad inicial de la HRP sobre la oxidación de o-dianisidina o luminol fueron testados de modo sistemático mediante métodos colorimétricos y luminométricos. Los resultados muestran que las diluciones de fenol, incluyendo aquellas abajo del número de Avogadro, pudieron activar o inhibir la HRP en reacciones de tipo peroxidasa y oxidasa con un patrón sinusoidal. Los valores Km de los sustratos estudiados variaron paralelamente a la actividad peroxidasa/oxidasa de la HRP; la actividad máxima de la reacción peroxidasa correspondió a la actividad mínima en la reacción oxidasa y viceversa. El efecto también se mostró dependiente del tipo de solvente. La observación de las oscilaciones sinusoidales en la actividad de la HRP, dependientes de la tasa de disolución del fenol y del tiempo de preincubación, llevan a concluir que la HRP puede ser un buen modelo para la investigación de las altas diluciones. Los experimentos ofrecen fuertes evidencias a favor de la HRP como detector muy sensible de cambios mínimos en la concentración de fenol, utilizado como cofactor en la reacción peroxidasa/oxigenasa. Palabras-clave: HR-peroxidasa, oxidasa-peroxidasa, fenol, hormesis, homeopatía, altas diluciones.   Correspondence author: Elzbieta Malarczyk, [email protected] How to cite this article: Malarczyk E. Kinetic changes in the activity of HR-peroxidase induced by very low doses of phenol. Int J High Dilution Res [online]. 2008 [cited YYYY Mmm DD]; 7(23): 48-55. Available from: http://journal.giri-society.org/index.php/ijhdr/article/view/37/349.  


2021 ◽  
Vol 14 (4) ◽  
pp. 1730-1736
Author(s):  
Kalpana. P. R

Chitosan, a cationic biopolymer is a major derivative of chitin. It is biocompatible, non-toxic and environ-friendly material and has broad spectrum antimicrobial activity. However, it is less effective in neutral or basic conditions due to its solubility only in acidic medium. Therefore, chemical modification with suitable groups is necessary to enhance the potency of chitosan. The present study was mainly conducted to explore the effect of structural modifications on antimicrobial potential of chitosan. N-Methyl, N-Ethyl and N-Propyl pyrrole were reacted with N-chloroacyl-6-O-triphenylmethylchitosan prepared by stepwise modification of chitosan to form N-Methyl, N-Ethyl and N-Propyl pyrrole derivatives of chitosan. Structural characterization of these pyrrole derivatives was done by IR, NMR, XRD, DSC and Elemental Analysis. The gram-negative bacterium Escherichia coli, gram-positive bacterium Staphylococcus aureus were selected for antibacterial activity and the fungus C. albicans was selected for antifungal activity by agar diffusion method and MIC method. Antimicrobial activity of the N-Methyl, N-Ethyl and N-Propyl pyrrole derivatives on E. coli, S. aureus and C. albicans showed an inhibitory effect on all the organisms. The potency of inhibition was found to be varied with the substitutions. The maximum activity was shown by N-pyrrolylpropylchitosan against E. coli (zone of inhibition 1.2±0.05cm, MIC 0.15±0.03mg/ml), S. aureus (zone of inhibition 1.4±0.03cm, MIC 0.15±0.01mg/ml), C. albicans (zone of inhibition 0.8±0.03cm, MIC 0.2±0.03mg/ml). The study also confirmed that all the three derivatives exhibited higher inhibition than that of chitosan against E. coli (zone of inhibition 0.7±0.03cm, MIC 0.09±0.02mg/ml), S. aureus (zone of inhibition 0.8±0.03cm, MIC 0.09±0.02mg/ml), C. albicans (zone of inhibition 0.6±0.03cm, MIC 0.09±0.03mg/ml). Results demonstrated that these three N-alkylpyrrole chitosan derivatives exhibited improved potency and hence can have the more applicability as antimicrobials.


2021 ◽  
Vol 10 (1) ◽  
pp. 29
Author(s):  
Dawoon Chung ◽  
Woon-Jong Yu ◽  
Ji-Yeon Lim ◽  
Nam-Seon Kang ◽  
Yong-Min Kwon ◽  
...  

Salterns are hypersaline environments that are inhabited by diverse halophilic microorganisms, including fungi. In this study, we isolated a fungal strain SK1-1 from a saltern in the Republic of Korea, which was identified as Asperillus reticulatus. This is the first reported saline-environment-derived A. reticulatus that belongs to the Aspergillus penicillioides clade and encompasses xerophilic fungi. SK1-1 was halophilic, obligately requiring NaCl for growth, with a maximum radial growth of 6%–9% (w/v) NaCl. To facilitate the biotechnological application of halophilic fungi, we screened the SK1-1 strain for proteolytic activity. Proteases have widespread applications in food processing, detergents, textiles, and waste treatment, and halophilic proteases can enable protein degradation in high salt environments. We assessed the proteolytic activity of the extracellular crude enzyme of SK1-1 using azocasein as a substrate. The crude protease exhibited maximum activity at 40–50 °C, pH 9.5–10.5, and in the absence of NaCl. It was also able to retain up to 69% of its maximum activity until 7% NaCl. Protease inhibitor assays showed complete inhibition of the proteolytic activity of crude enzymes by Pefabloc® SC. Our data suggest that the halophilic A. reticulatus strain SK1-1 produces an extracellular alkaline serine protease.


MAUSAM ◽  
2021 ◽  
Vol 65 (1) ◽  
pp. 73-82
Author(s):  
KGHOSH GHOSH ◽  
MRAJAVEL RAJAVEL ◽  
R.P. SAMUI ◽  
G.P. SINGH ◽  
C. KARMAKAR

A study on pest population of American boll worm (Heliothis armigera H.) in cotton crop as influenced by weather parameters like rainfall (RF), maximum temperature (Tmax), minimum temperature (Tmin), morning relative humidity (RH I), evening relative humidity (RH II) and bright sunshine hours (BSS) and its statistical correlation was undertaken with data recorded at Dr. Punjabrao Deshmukh Krishi Vidhyapeeth, Akola. The maximum activity and damage due to high population of Heliothis was observed during 35th to 50th standard weeks. Maximum temperature (40th week) and minimum temperature (37th week), morning and evening relative humidity during 38th week play an important role in pest infestation during 40th standard week. Flowering to boll formation stages of the crop suffered heavy incidence of Heliothis. Critical weather parameters causing the outbreak of Heliothis in Akola was maximum temperature around 32 °C and minimum temperature around 23 °C, morning relative humidity below 88%, evening relative humidity below 60% and hours of bright sunshine above 6.5 hrs / day.


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