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Background: Lignin is a complex polymer of phenyl propanoid units found in the vascular tissues of the plants as one of lignocellulose materials. Many bacteria secrete enzymes to lyse lignin, which can be essential to ease the production of bioethanol. Current research focused on the study of ligninolytic bacteria capable of producing lignin peroxidase (LiP) which can help in lignin biodegradation and bioethanol production. Ligninolytic bacterial strains were isolated and screened from the soil samples of Simlipal Biosphere Reserve (SBR), Odisha (India), for the determination of their LiP activity. Enzymatic assay and optimization for the LiP activity were performed with the most potent bacterial strain. The strain was identified by morphological, biochemical, and molecular methods. Results: In this study, a total of 16 bacteria (Simlipal ligninolytic bacteria [SLB] 1–16) were isolated from forest soils of SBR using minimal salt medium containing lignin. Out of the 16 isolates, 9 isolates showed decolourization of methylene blue dye on LB agar plates. The bacterial isolates such as SLB8, SLB9, and SLB10 were able to decolourize lignin with 15.51%, 16.80%, and 33.02%, respectively. Further enzyme assay was performed using H2O2 as substrate and methylene blue as an indicator for these three bacterial strains in lignin containing minimal salt medium where the isolate SLB10 showed the highest LiP activity (31.711 U/mg). The most potent strain, SLB10, was optimized for enhanced LiP enzyme activity using response surface methodology. In the optimized condition of pH 10.5, temperature 30 °C, H2O2 concentration 0.115 mM, and time 42 h, SLB10 showed a maximum LiP activity of 55.947 U/mg with an increase of 1.76 times from un-optimized condition. Further chemical optimization was performed, and maximum LiP activity as well as significant dye-decolourization efficiency of SLB10 has been found in bacterial growth medium supplemented individually with cellulose, yeast extract, and MnSO4. Most notably, yeast extract and MnSO4-supplemented bacterial culture medium were shown to have even higher percentage of dye decolourization compared to normal basal medium. The bacterial strain SLB10 was identified as Bacillus mycoides according to morphological, biochemical, and molecular (16S rRNA sequencing) characterization and phylogenetic tree analysis. Conclusion: Result from the present study revealed the potential of Bacillus mycoides bacterium isolated from the forest soil of SBR in producing LiP enzyme that can be evaluated further for application in lignin biodegradation and bioethanol production. Scaling up of LiP production from this potent bacterial strain could be useful in different industrial applications. [ABSTRACT FROM AUTHOR]

Background: Phyllanthus species exhibit a wide range of in vitro and in vivo pharmacological activities; however, little is known about the compounds present in the extracts that are responsible for such actions. Objective: Development and validation of a simple reversed phase HPLC-PDA method for profiling of phyllanthin, hypophyllanthin, nirtetralin, and niranthin in extracts of Phyllanthus species was carried out. Methods: Separation was achieved using an XBridge column® (150x4.6mm, 5.0 µm id) in an isocratic elution mode with mobile phase comprising of a mixture of acetonitrile and water with TFA (0.05%, v/v, pH=2.15) at ambient temperature with a flow rate of 1 mL/min. Results: Phyllanthin, hypophyllanthin, nirtetralin, and niranthin were eluted at mean retention times of 10.47, 11.10, 13.67, and 14.53 min, respectively. LOD and LOQ for all four analytes were 0.75 and 3.00 µg/mL, respectively. RSDr values for intraday and interday precision for phyllanthin, hypophyllanthin, nirtetralin, and niranthin were 0.38-1.32 and 0.45-1.77%; 0.22-3.69 and 0.24-3.04%, 0.73-2.37 and 0.09-0.31%, and 1.56-2.77 and 0.12-0.68%, respectively. Conclusions: The developed and validated HPLC-PDA method was applied for identification and quantification of phyllanthin, hypophyllanthin, nirtetralin, and niranthin in extracts of different plant parts of selected Phyllanthus species. The outcome of the present investigation could be useful for selection of best species to promote its commercial cultivation and suitable extraction solvent for preparation of lignan-enriched fractions. This HPLC-PDA method could be useful for quality control of herbal formulations containing plants from Phyllanthus species. [ABSTRACT FROM AUTHOR]

Myristica fragrans Houtt., the source of very important spice 'nutmeg' used world over is native to India, Indonesia, Sri Lanka, South Africa and Southeast Asia. Phytochemical investigation of M. fragrans stem bark led to the isolation of bis-aryl dimethyl tetrahydrofuran lignans, such as grandisin [(7S,8S,7′S,8′S)-3,3′,4,4′,5,5′-hexamethoxy-7,7′,8,8′-lignan] and (7S,8S,7′R,8′R)-3,3′,4,4′,5,5′-hexamethoxy-7,7′,8,8′-lignan along with important lignans and neolignans, licarinA, licarin B, odoratisol A, (2S, 3R)-7-methoxy-3-methyl-5-((E)-prop-1-enyl)-2-(5-methoxy,3,4-methylenedioxyphenyl)-2,3-dihydrobenzofuran, elemicin, fragransin B1, raphidecursinol B, erythro-(7S,8R)-Δ8′-4,7-dihydroxy-3,5,3′-trimethoxy-8-O-4′-neolignan, erythro-(7S,8R)-Δ8′-7-hydroxy-3,4,3′,5′-tetramethoxy-8-O-4′-neolignan, surinamensin.and β-sitosterol. Structures of the 12 compounds isolated were unambiguously identified by various spectroscopic methods. The former two compounds were isolated from M. fragrans for the first time. Furthermore, the X-ray crystal structure of odoratisol A is reported in this paper for the first time. [ABSTRACT FROM AUTHOR]

Abstract: Podophyllum hexandrum Royle (Syn. P. emodi Wale) a perennial rhizomatous herb found in alpine region distributed in the entire range of Himalayas from Ladakh to Sikkim at an altitude of 3000–4200masl is an preferred commercial source of Podophyllum lignans. It contains three times more Podophyllotoxin than the American species, Podophyllum peltatum. The present study was aimed to investigate variation of Podophyllum lignans contents based on six marker compounds viz. Podophyllotoxin; Deoxypodophyllotoxin; Picropodophyllotoxin; Podophyllotoxin β-d-glucopyanoside; Isopicropodophyllone; 4′-Demethyldeoxypodophyllotoxin, β-d-lucopyanoside, in P. hexandrum population growing at three locations. Further, ontogenetic and morphogenetic variations of Podophyllum lignan contents were studied to investigate dynamics of accumulation of these compounds. Representative collections from three locations viz., Panikhar, Padam and Tangoli located in Trans Himalayan semi-desert region of Zanskar valley were harvested at three stages (dormancy, active growth and maturity). Plants were dissected into root, rhizome and rhizome-buds, dried separately and assayed for Podophyllum lignan contents by high performance liquid chromatography. [Copyright &y& Elsevier]

Spectrofluorometric quantitation of a lignan lactone, diphyllin, and its glycosides cleistanthin A and cleistanthin B, the active principles of the poisonous plant Cleistanthus collinus, is reported for the first time. Thin layer chromatographic resolution of the components precedes the fluorometric measurements. The method is highly reproducible and sensitive to 0.1 microgram/mL for diphyllin and to 1 microgram/mL for cleistanthins A and B in ethanol. The technique is employed for the assay of several biospecimens of forensic and clinical importance.