Madhuri Kaushish Lily

Desulfurization of dibenzothiophene (DBT) by a novel strain Lysinibacillus sphaericus DMT-7 isolated from diesel contaminated soil

A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620) using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively. The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.

Evaluation and comparison of polyphenols and bioactivities of wild edible fruits of North-West Himalaya, India

ABSTRACT Objective To evaluate and compare the polyphenol contents, antioxidant, anti-elastase, anti-collagenase, anti-tyrosinase and anti-inflammatory activities of 13 wild edible fruits [ Pyracantha crenulata, Berberis asiatica ( B. asiatica ) , Ficus subincisa ( F. subincisa ) , Morus serrata, Ziziphus nummularia, Leea asiatica ( L. asiatica ) , Dendrobenthamia capitata, Ziziphus mauritiana, Prunus cerasoides, Ampelocissus latifolia ( A. latifolia ) , Vitis jacquemontii, Morus alba and Grewia optiva ] of North-West Himalayan Region of India. Methods Fruits extracts were prepared with 80% aqueous acetone and evaluated for total phenolic contents (TPC) and total flavonoid contents (TFC). Free radical scavenging activities [against 1,1-diphenyl-2-picryl-hydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), linoleate hydroperoxyl and superoxide radicals], ferric reducing ability, ferrous metal chelating capacity, anti-elastase, anti-collagenase, anti-tyrosinase and anti-inflammatory activities were determined by using various in vitro assays. Results TPC varied from 58.83 to 4 496.39 mg gallic acid equivalents/100 g fruit weight (FW), being highest in A. latifolia and lowest in F. subincisa . TFC ranged from 108.00 to 1 963.75 mg catechin equivalents/100 g FW, standing highest in L. asiatica and lowest in Prunus cerasoides. A. latifolia and L. asiatica possessed the highest antioxidant activities while B. asiatica and L. asiatica owned uppermost anti-elastase and anti-collagenase activities, respectively. B. asiatica revealed the highest anti-tyrosinase activity and F. subincisa demonstrated the highest anti-inflammatory activity. The present study revealed differential contribution of TPC and TFC in various antioxidant activities. However, no obvious relationship was visible between anti-elastase/anti-collagenase/anti-tyrosinase/anti-inflammatory activities and TPC/TFC, suggesting the role of individual or combination of specific phenolics and flavonoids. Conclusions The abilities of Himalayan wild edible fruits to scavenge a variety of free radicals, inhibit enzymes causing skin-aging and skin-darkening are highly appreciable, suggesting their possible utilization for the development of effective formulations for general health maintenance and anti-aging, skin-whitening cosmetics.

Viburnum mullaha D. DON fruit (Indian cranberry): A potential source of polyphenol with rich antioxidant, anti-elastase, anti-collagenase, and anti-tyrosinase activities

ABSTRACT Viburnum mullaha (Buch.-Ham. Ex D. Don), is an underexplored wild edible fruit of Indian Himalayan region, analyzed for total polyphenol contents, antioxidant, anti-elastase, anti-collagenase, and anti-tyrosinase activities using in vitro assays. High values of total phenolic contents of 1257 ± 40 mg gallic acid equivalents/100 g fruit weight and total flavonoid contents of 3501 ± 203 mg catechin equivalents/100 g fruit weight were observed. V. mullaha fruit extracts showed outstanding antioxidant activities (ABTS+, 1,1-diphenyl-2-picrylhydrazyl, superoxide anion, linoleate peroxyl radicals scavenging, and ferric reducing activities) and remarkable anti-elastase, anti-collagenase, and anti-tyrosinase activities. High resolution liquid chromatography–mass spectroscopy analysis revealed presence of 15 phenolic compounds, namely, chlorogenic acid, acetyl salicylic acid, dihydrorobinetin, dihydromyricetin, 2-isoprenylemodin, rutin, cosmosiin hexaacetate, pectolinarin, dihydroquercetin, eriodictyol, iriginol hexaacetate, theaflavin, epicatechin-pentaacetate, lomatin, and peucenin in fruit extracts. This study recommends utilization of V. mullaha fruit as functional food with prospective pharmaceutical, nutraceutical, and cosmeceutical properties.

Comparative purification and characterization of two distinct extracellular monocrotophos hydrolases secreted by Penicillium aculeatum and Fusarium pallidoroseum isolated from agricultural fields.

The present study aimed at a comparative characterization of two distinct extracellular monocrotophos hydrolases, from Penicillium aculeatum ITCC 7980.10 (M3) and Fusarium pallidoroseum ITCC 7785.10 (M4), isolated from agricultural fields. The MCP hydrolases were purified by Sephadex G-100 column and DEAE-Sepharose CL-6B ion-exchange column followed by SDS–PAGE analysis, which showed the presence of two hydrolases, of 33 and 67 kDa respectively. Both enzymes were most active at alkaline pH and were stable over a wide range of temperatures (60–70 °C). Between the strains, the MCP hydrolases from M3 were 2-fold more active than that from M4. Enzyme kinetic studies showed lowest K m (33.52 mM) and highest V max (5.18 U/mg protein) for OPH67 of M3 in comparison to the K m and V max of the other hydrolases purified from M3 and M4, suggesting that M3 OPH67 was the most efficient MCP hydrolase. To the best of our knowledge, this is the first report of the purification of two distinct extracellular thermostable MCP hydrolases from fungal strains Penicillium aculeatum ITCC 7980.10 and Fusarium pallidoroseum ITCC 7785.10. Owing to its potential MCP hydrolyzing activity, M3 OPH67 can perhaps used directly or in the encapsulated form for remediation of MCP contaminated sites.

Benzo(a)pyrene degradation pathway in Bacillus subtilis BMT4i (MTCC 9447)

Abstract Background Benzo(a)pyrene (BaP), a high molecular weight pentacyclic aromatic hydrocarbon, is a priority pollutant of extreme concern. Bacillus subtilis BMT4i (MTCC 9447) degrades BaP through chromosomally encoded pathway. Nevertheless, inadequate information is available on BaP degradation pathway in genus Bacillus despite of its species being shown as potent BaP degrader. The objective of this study was to elucidate BaP degradation pathway in B. subtilis strain BMT4i by identifying metabolites through UHPLC-MS. Materials and methods Batch experiments were conducted to characterize metabolic pathway of BaP in the bacterium B. subtilis BMT4i. The metabolites were separated and characterized by UHPLC-MS. Results The major intermediates of BaP metabolism that had accumulated in the culture media after 15 days of incubation were benzo(a)pyrene-11,12-epoxide, 7,8,9,10-tetrahydrobenzo[pqr]tetraphene-7,8,9,10-tetraol, benzo(a)pyrene-cis-7,8-dihydrodiol, 8-carboxy-7-hydroxy pyrene, chrysene-4 or 5-carboxylic acid, cis-4-(8-hydroxypyrene-7yl)-2-oxobut-3-enoic acid, hydroxymethoxybenzo(a)pyrene and dimethoxybenzo(a)pyrene. Among above, 8-carboxy-7-hydroxy pyrene, chrysene-4 or 5-carboxylic acid, and cis-4-(8-hydroxypyrene-7yl)-2-oxobut-3-enoic acid are ring cleavage products of BaP. Conclusion The identified metabolites indicated that BMT4i initially oxidized BaP with monooxygenases and dioxygenases at C-11,12 or and C-7,8 and C-9,10 positions, suggesting operation of multiple pathways for BaP degradation in B. subtilis. Further studies are essential to find out whether the entire biodegradation process in B. subtilis results into metabolic detoxification of BaP or not.