Development and validation of a High performance liquid chromatography-Mass spectrometry method for 17 a -methyltestosterone in Aquatic water systems
Ashok Marwah*1, Xu Nianzu2, Padma Marwah1 and Terence P. Barry3
1Department of Biochemistry, Institute for Enzyme Research, University of Wisconsin at Madison, 1710 University Avenue, Madison, WI 53726, USA
3Department of Animal Science, University of Wisconsin, 660 N Park St., Madison, WI 53706, USA
1Current address: Chemilent Inc., 5240 Tennyson Parkway, #207 , Plano , TX 75024 , USA
2Current address: Key Lab of Marine Biotechnology, Ningbo University , Ningbo , 513211, P. R. CHINA
*Corresponding author. E-mail: email@example.com
Abstract : 17 a -Methyltestosterone is used as feed additive to manipulate the gender of fish for aquaculture. Earlier a simple, yet specific and robust validated high performance liquid chromatographic method has been developed for the determination of 17 a-methyltestosterone in fish feed. The present work describes a highly sensitive and robust Liquid Chromatography-Mass Spectrometry method for the quantitation of 17 a-methyltestosterone in aquatic water systems using 17 β-hydroxy-3 β-methoxyandrost-5-en-7-one as internal standard. The method was validated in the concentration range of 0.2 to 25 ng of 17 a -methyltestosterone on column leading to a limit of quantitation of 0.08 ppb or 0.08 mg/L in water, and has potential to increase the limit of detection and quantitation by an order of magnitude, if required.
Keywords : High-performance liquid chromatography-Mass spectrometry, Electrospray ionization, 17 a -Methyltestosterone, Solid phase extraction, Method validation
Studies on pollinator fauna and their relative abundance of sunflower (Helianthus annuus L.) at Pantnagar, Uttarakhand, India
Vimla Goswami*, M. S. Khan and Usha
Department of Entomology, College of Agriculture, G.B. Pant University of Agriculture and Technology, Pantnagar-263145 (Uttarakhand), INDIA
*Corresponding author. E-mail: firstname.lastname@example.org
Abstract : Pollinators provide key services to both natural and agricultural ecosystems. Agricultural productivity depends, in part on pollinator populations from adjacent semi natural habitats.The diversity and abundance of different insect visitors on sunflower (Helianthus annuus L.) were studied at Pantnagar. A total of 12 insect visitors belonging to order Hymenoptera (9), Diptera (1), Lepidoptera (1), and Coleoptera (1) were observed visiting the blossom of sunflower. The abundance (percentage of insect/m2/2min.) of Hymenopterans were maximum (86.09 %) followed by the Dipterans (22.80 %) and others (3.87%). In Hymenopterans, the honeybees (Apis bees) were observed maximum (65.22 %) followed by non Apis bees (20.39 %) and the scolid wasp (1.69 %).
Keywords : Abundance, Diversity, Helianthus annuus, Pollinator