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Development and validation of an HPTLC method for estimation of coronarin D in Hedychium coronarium rhizome

Ray A., Dash B., Sahoo S., Sahoo A., Jena S., Kar B., Chatterjee T., Ghosh B., Nayak S.

Acta Chromatographica

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2017

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Vol. 29, no. 3

415--426

EN

Rhizome extracts of Hedychium coronarium are widely used as phytotherapeutics. As of date, there is no documented study on the standardization of H. coronarium extract, and the following research is an effort in this direction. Coronarin D is an important bioactive compound present in H. coronarium which shows chemopreventive activity against cancer. H. coronarium extracts were assessed for coronarin D content for the first time. The extraction was checked using different solvents: n-hexane, acetone, and methanol. Coronarin D was separated on silica gel 60F254 high-performance thin-layer chromatography (HPTLC) plates by isocratic gradient method using n-hexane-ethyl acetate (80:20 v/v) as mobile phase. Densitometric quantification was performed at 231 nm in absorption mode. This method gave a well-defined peak at Rf 0.20 corresponding to coronarin D. The method was validated using International Conference on Harmonization (ICH) guidelines in terms of precision, repeatability, and accuracy. Linearity range of coronarin D was 200–1000 ng spot−1 with a correlation coefficient of R2 ± SD = 0.9987 ± 2.62% in the concentration range of 200–1000 ng spot−1. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 35 and 115 ng, respectively. Accuracy of the method was checked by recovery studies conducted at three different concentration levels, and the average percentage recovery was found to be 98.22 % for coronarin D. Among the different solvents, acetone produced maximum extraction efficiency of coronarin D. The proposed HPTLC method can be applied for robust identification and quantitative determination of coronarin D in H. coronarium extracts.

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A note on inventory model for ameliorating items with time dependent second order demand rate

Panda G. C., Sahoo S., Sukla P K

LogForum

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2013

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Vol. 9, no. 1

43--49

EN

Background: This paper is concerned with the development of ameliorating inventory models. The ameliorating inventory is the inventory of goods whose utility increases over the time by ameliorating activation. Material and Methods: This study is performed according to two areas: one is an economic order quantity (EOQ) model for the items whose utility is ameliorating in accordance with Weibull distribution, and the other is a partial selling quantity (PSQ) model developed for selling the surplus inventory accumulated by ameliorating activation with linear demand. The aim of this paper was to develop a mathematical model for inventory type concerned in the paper. Numerical examples were presented show the effect of ameliorating rate on inventory polices. Results and Conclusions: The inventory model for items with Weibull ameliorating is developed. For the case of small ameliorating rate (less than linear demand rate), EOQ model is developed, and for the case where ameliorating rate is greater than linear demand rate, PSQ model is developed.

PL

Wstęp: Praca porusza zagadnienie rozwoju modeli zarządzania zapasem dla produktów przetworzonych. Dotyczy ona produktów, których użyteczność wzrasta wraz z upływem czasu poprzez zastosowanie procesów ich obróbki ulepszania. Materiały i metody: W pracy oparto się na dwóch modelach: pierwszy z nich to model ekonomicznej wielkości zamówienia (EOQ) dla towarów, których użyteczność wzrasta zgodnie z dystrybucją Weibulla, natomiast drugi to model częściowej sprzedaży (PSQ) nadwyżek zapas nagromadzonych poprzez aktywności mające poprawę ich użyteczności i charakteryzujące się popytem liniowym. Celem tej pracy było wypracowanie matematycznego modelu dla zarządzania zapasem dla typu towarów omawianych tutaj. Praktyczne działanie modelu przedstawiono na zaprezentowanych przykładach. Wyniki i wnioski: Wypracowano model zarządzania zapasem towarów podlegających wzroście wartości Weibulla. Dla przypadku, gdy wskaźnik poprawy przybierał niską wartość (mniejszą niż wskaźnik popytu liniowego) opracowano model EOQ, natomiast dla przypadku, gdy ten wskaźnik był większy niż wskaźnik popytu liniowego, opracowano model PSQ.

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Naturally occurring radionuclides and rare earth elements in weathered Japanese soil samples

Sahoo S., Hosoda M., Prasad G., Takahashi H., Sorimachi A., Ishikawa T., Tokonami S., Uchida S.

Acta Geophysica

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2013

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Vol. 61, no. 4

876--885

EN

The activity concentrations of 226Ra and 228Ac in weathered Japanese soils from two selected prefectures have been measured using a γ-ray spectroscopy system with high purity germanium detector. The uranium, thorium, and rare earth elements (REEs) concentrations were determined from the same soil samples using inductively coupled plasma mass spectrometry (ICP-MS). For example, granitic rocks contain higher amounts of U, Th, and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils since soils are complex heterogeneous mixture of organic and inorganic solids, water, and gases. In this paper, we will discuss about distribution pattern of 238U and 232Th along with REEs in soil samples of weathered acid rock (granite) collected from two prefectures of Japan: Hiroshima and Miyagi.

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Natural radionuclide analysis in Chattarpur area of southeastern coastal area of Odisha, India

Rautela B., Gusain G., Yadav M., Sahoo S., Tokonami S., Ramola R.C.

Acta Geophysica

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2013

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Vol. 61, no. 4

1038--1045

EN

The energy released in a spontaneous decay process of natural radionuclides is the main source of the total radiation dose to human beings. Natural radionuclides are widely distributed in soil, rocks, air, and groundwater. In present investigation, the analysis of terrestrial radionuclides such as 226Ra, 232Th, and 40K in soil and sand of Chattarpur area of southeastern coast of Odisha has been carried out using NaI(Tl) gamma ray detector. The higher activity concentrations of naturally occurring radionuclides have been reported from the study area. The gamma radiationdose originating from the terrestrial radionuclides was found to vary from 95 to 1813 nGy/h with an average of 700 nGy/h. This study is important to generate a baseline data of radiation exposure in the area. Health hazard effects due to natural radiation exposure are discussed in details.

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Effect of dual fillers on the properties of acrylonitrile butadiene rubber nanocomposites in presence of compatibilizer

Rajasekar R., Nayak G.C., Malas A., Sahoo S., Das C.K.

Elastomery

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2011

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T. 15, nr 3

3-13

EN

Acrylonitrile butadiene rubber (NBR) nanocomposites containing nanoclay and carbon black were prepared in presence of compatibilizer. The nanoclay used in this study is Cloisite 20A and the compatibilizer used for dispersing nanoclay in NBR is epoxidized natural rubber (ENR). The preparation of NBR nanocomposites involves two step processes. Initially nanoclay was incorporated in ENR by solution mixing. The minimum loading of the obtained ENR-nanoclay composites (EC) were incorporated in NBR followed by the addition of carbon black. The changes obtained in the morphological, mechanical, swelling and compression set properties upon minimum loading of nanoclay in the carbon black filled NBR compounds were analysed and compared with gum and carbon black filled NBR systems. The morphological studies proved the intercalation of nanoclay in ENR. Incorporation of EC in NBR in presence of carbon black leads to partial exfoliation of nanoclay platelets in the NBR matrix. Curing studies depicted faster scorch time, cure time and increase in torque for the dual filler containing NBR compounds. Dynamic mechanical thermal analysis (DMTA) showed increase in storage modulus and lesser damping characteristics for the dual filler containing NBR compounds accompanied with significant improvement in mechanical, resistance to swelling and low compression set properties.

PL

Nanokompozyty kauczuku butadienowo-akrylonitrylowgo (NBR) zawierające nanoglinokrzemian (Cloisite 20A) i sadzę przygotowano w obecności kompatybilizatora. Jako kompatybilizatora ułatwiającego dyspergowanie nanokrzemianu w NBR użyto epoksydowanego kauczuku naturalnego (ENR). Proces przygotowania nanokompozytów NBR przebiegał dwuetapowo. Najpierw wprowadzano nanokrzemian do ENR przez mieszanie w roztworze. Niewielką ilość uzyskanych kompozytów ENR-nanokrzemian (EC) wprowadzono do NBR, a następnie dodawano sadzę. Przeanalizowano właściwości morfologiczne i mechaniczne oraz pęcznienie i odkształcenie trwałe tak zmodyfikowanych mieszanek. Uzyskane wyniki porównano z właściwościami mieszanek NBR napełnionych tylko sadzą oraz niezawierających napełniaczy. Badania morfologiczne potwierdziły interkalację nanokrzemianu w ENR Stwierdzono, że dodanie EC do NBR w obecności sadzy prowadzi do częściowej eksfoliacji płytek nanoglinokrzemianu w matrycy NBR. Mieszanki NBR zawierające obydwa napełniacze odznaczały się krótszym czasem podwulkanizacji, wulkanizacji i wzrostem momentu obrotowego. Analiza termiczna dynamiczno-mechaniczna (DMTA) wykazała wzrost składowej rzeczywistej modułu zespolonego i gorsze właściwości tłumiące mieszanek NBR zawierających dwuskładnikowy zespół napełniaczy, czemu towarzyszyła znacząca poprawa właściwości mechanicznych, odporności na pęcznienie oraz małe odkształcenie trwałe.