Botany


https://sites.google.com/a/gauhati.ac.in/research/#ds11092019 Vermicomposting citronella waste

https://sites.google.com/a/gauhati.ac.in/research/botany/#sb14032019 A new plant species from Assam

https://sites.google.com/a/gauhati.ac.in/research/botany#kt09012019 Isolating antimicrobial compounds

https://sites.google.com/a/gauhati.ac.in/research/botany/#kt21112018 Funiculosone - an antimicrobial metabolites

Vermicomposting citronella waste and a mixture of sludge

Hemen Deka and coworkers report about vermicomposting of citronella bagasse and mixture of paper-mill sludge. This work is published in the journal Bioresource Technology.



Authors
T Boruah, A Barman, P Kalita, J Lahkar1, and H Deka
from other institution

Abstract
The vermicomposting potential of Eisenia fetida on citronella bagasse and paper mill sludge mixture was studied. The experiment was carried out in pots by taking a mixture of citronella bagasse and paper mill sludge in 3:2 ratios. The physico-chemical properties such as pH, conductivity, total organic carbon, nitrogen, phosphorus, potassium, calcium, trace elements and heavy metals were studied in the end products. The ash content, humification index, C/N ratio and scanning electron microscopic analysis were done to understand the maturity of the vermicompost. Results revealed that bioconversion of citronella bagasse and paper mill sludge mixture is accompanied with reduction of C/N ratio and humification index; enhancement of nutrients profile, nitrogen fixing, phosphate and potassium solubilising bacterial population. SEM analysis showed that there was more disintegration in vermicompost samples than the initial raw materials and compost. Further, earthworm population and biomass has significantly increased by the end of the experimental trials.

https://sites.google.com/a/gauhati.ac.in/research/botany/#top 
 



Impatiens kamrupana - a new plant species from Assam

Souravjyoti Borah and fellow researchers report about discovery of a new plant species Impatiens kamrupana (Balsaminaceae) from Assam. This is now listed and published in the journal Phytotaxa.


Authors
Souravjyoti Borah, Jatindra Sarma, and Rajib Gogoi

Abstract
Impatiens Kamrupana - a new species is discovered from Kamrup district (rural) of Assam, bordering the adjoining state of Meghalaya. The new species is easily distinguished from its allied taxa by its bicoloured, white and purple flowers and sub-bucciniform lower sepal with straight to slightly curved spur.

Journal Reference
https://sites.google.com/a/gauhati.ac.in/research/botany/#top 
 



Isolating antimicrobial compounds

Kumanand Tayung and fellow researchers have been successful in isolating antimicrobial compound named aspergyllone. This research work is published in Natural Product Research. 



Authors
Srichandan Padhi1, Marco Masi1, Sujogya K Panda1, Walter Luyten1, Alessio Cimmino1, Kumanand Tayung, and Antonio Evidente1
1 from other institutions

Abstract
A new 6-benzyl-γ-pyrone (1), named aspergyllone was isolated from the culture filtrates of an endolichenic fungus Aspergillus niger Tiegh, obtained from lichen thallus Parmotrema ravum (Krog & Swinscow) Serus, collected in India. 1 was isolated for the first time from an endolichenic fungus together with six other known metabolites identified as aurasperones A (2) and D (3), asperpyr- one A (4), fonsecinone A (5), carbonarone A (6) and pyrophen (7). The compounds were tested against a panel of human, plant, food borne and fish pathogens. Aspergyllone showed strong selective antifungal activity against Candida parapsilosis (Ashford) Langeron & Talice, with an IC50 of 52 μg/mL. Aurasperone A and pyrophen showed moderate to strong antimicrobial activity inhibiting seven different test pathogens, being pyrophen active with IC50 ranging from 35 to 97 μg/mL.

Journal Reference
https://sites.google.com/a/gauhati.ac.in/research/botany#top 
 



Funiculosone - a new antimicrobial metabolites

Kumanand Tayung and his collaborators have isolated a new antimicrobial metabolites which also shows anticandidal activity against Candida albicans Berkhout. This research is published in the journal Phytochemistry.



Authors
Srichanadan Padhi1, Marco Masi1, Alessio Cimmino1, Angela Tuzi1, Subhrakanta Jena1, Kumananda Tayung, and Antonio Evidente1
1 from other institutions

Abstract
An undescribed substituted dihydroxanthene-1,9-dione, named funiculosone, was isolated together with its two analogues identified as mangrovamide J and ravenelin, from the culture filtrates of Talaromyces funiculosus (Thom) Samson, Yilmaz, Frisvad & Seifert (Trichocomaceae), an endolichenic fungus isolated from lichen thallus of Diorygma hieroglyphicum (Pers.) Staiger & Kalb (Graphidaceae), in India. Funiculosone was characterised, essentially by spectroscopic methods, as 4,8,9a-trihydroxy-3,4a-dimethyl-4a,9a-dihydro-4H-xanthene-1,9-dione. Its relative stereochemistry was deduced by single crystal X-ray analysis while the absolute configuration was assigned as 4S,4aS,9aS by ECD spectra in comparison to that of the closely related mangrovamide J. This latter, to which, not being an amide, an inappropriate common name was given, was only recently isolated, together with undescribed and known prenylatedindole alkaloids and chromone derivatives from an unidentified Penicillium sp. X-ray structural analysis of the isolated mangrovamide J, for which no biological activity was previously reported, revealed polymorphism and a new crystalline phase is described. All the compounds displayed antibacterial activity with an IC50 range 23–104 μg/mL when assayed against Escherichia coli Escherich and Staphylococcus aureus Ogston. Funiculosone also showed anticandidal activity against Candida albicans Berkhout with an IC50 35 μg/mL.

Journal Reference
https://sites.google.com/a/gauhati.ac.in/research/botany/#top