Counter-current chromatography for the separation of terpenoids: A comprehensive review with respect to the solvent systems employed

Copyright @ 2014 The Authors.This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Natural products extracts are commonly highly complex mixtures of active compounds and consequently their purification becomes a particularly challenging task. The development of a purification protocol to extract a single active component from the many hundreds that are often present in the mixture is something that can take months or even years to achieve, thus it is important for the natural product chemist to have, at their disposal, a broad range of diverse purification techniques. Counter-current chromatography (CCC) is one such separation technique utilising two immiscible phases, one as the stationary phase (retained in a spinning coil by centrifugal forces) and the second as the mobile phase. The method benefits from a number of advantages when compared with the more traditional liquid-solid separation methods, such as no irreversible adsorption, total recovery of the injected sample, minimal tailing of peaks, low risk of sample denaturation, the ability to accept particulates, and a low solvent consumption. The selection of an appropriate two-phase solvent system is critical to the running of CCC since this is both the mobile and the stationary phase of the system. However, this is also by far the most time consuming aspect of the technique and the one that most inhibits its general take-up. In recent years, numerous natural product purifications have been published using CCC from almost every country across the globe. Many of these papers are devoted to terpenoids-one of the most diverse groups. Naturally occurring terpenoids provide opportunities to discover new drugs but many of them are available at very low levels in nature and a huge number of them still remain unexplored. The collective knowledge on performing successful CCC separations of terpenoids has been gathered and reviewed by the authors, in order to create a comprehensive document that will be of great assistance in performing future purifications. © 2014 The Author(s)

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Not AvailableA study was conducted to assess the biological ability of Malpura rams to counter heat stress challenges and its impact on the productive performance in a semi-arid tropical environment. The eighteen adult Malpura rams (average body weight 55.0 kg) were divided into two groups, GI (n = 9; Control) and GII (n = 9; heat stress). The study was conducted for a period of 60 days. The results showed that body weight, body condition score, heart girth and feed intake were significantly (p < 0.05) lower in GII as compared to GI rams. The physiological responses i.e. respiration rate, pulse rate, rectal temperature and sweating rate (body and scrotum) were significantly (p < 0.05) higher in rams exposed to heat stress. Among the endocrine parameters, plasma T3, T4 and testosterone concentrations were significantly (p < 0.05) lower in GII rams, while cortisol concentration was significantly (p < 0.05) higher in GII rams. In addition, heat stress significantly (p < 0.05) reduced semen volume, total sperm motility, sperm concentration and progressive sperm motility in GII rams. The results indicated that Malpura rams adapted to the heat stress condition, however, while doing so their production performances were compromised.Not Availabl

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Not AvailableA study was conducted to assess the combined effect of heat stress and nutritional restriction on growth and reproductive performances in Malpura rams. Twenty‐eight adult Malpura rams (average body weight (BW) 66.0 kg) were used in this study. The rams were divided into four groups: CON (n = 7; control), HES (n = 7; heat stress), NUS (n = 7; nutritional stress) and COS (n = 7; combined stress). The study was conducted for a period of 2 months. CON and HES rams had ad libitum access to their feed while NUS and COS rams were under restricted feed (30% intake of CON rams) to induce nutritional stress. The HES and COS rams were kept in climatic chamber at 42 °C and 55% relative humidity for 6 h a day between 10 : 00 h and 16 : 00 h to induce heat stress. Body weight increased significantly (p < 0.05) in CON as compared to NUS and COS. When compared within groups, scrotal width morning, scrotal width afternoon, scrotal circumference morning and scrotal circumference afternoon were significantly (p < 0.05) larger in CON while smaller in COS rams. The higher testicular length was recorded both during morning (p < 0.05) and afternoon (p < 0.01) in COS rams while the lowest in NUS rams. The highest plasma testosterone concentration was recorded in CON and lowest in COS rams. Semen volume and mass motility also differed significantly (p < 0.05) between the groups. The highest semen volume and mass motility was recorded in CON and NUS while lowest in both HES and COS rams. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on reproductive performance of rams.Not Availabl

Impact of heat stress, nutritional stress and their combinations on the adaptive capability of Malpura sheep under hot semi-arid tropical environment.

Not AvailableA study was conducted to assess the cumulative effects of combined stresses (heat and nutritional) on physiological adaptability, blood biochemical and endocrine responses in Malpura rams. The study was conducted for a period of 45 days. Twenty eight adult Malpura rams (average BW 66.0 Kg) were used in the present study. The rams were divided into four groups viz., CON (n=7; control), HS (n=7; heat stress), NS (n=7; nutritional stress) and CS (n=7; combined stress). The animals were stall fed with a diet consisting of 60% roughage and 40% concentrate. The CON and HS ewes were provided with ad libitum feeding while NS and CS rams were provided with restricted feed (30% intake of GI ewes) to induce nutritional stress. The HS and NS rams were kept in climatic chamber @ 42ºC and 55% RH for six hours a day between 10:00 hr to 16:00 hr to induce heat stress. The parameters studied were respiration rate (RR), pulse rate (PR), rectal temperature (RT), scrotal volume, sweating rate scrotum, sweating rate skin, haemoglobin (Hb) and packed cell volume (PCV), plasma cortisol, T3 (tri-iodo-thyronine), and T4 (thyroxin) level. Combined stresses significantly (P<0.01) influenced all adaptive parameters studied. The study shows that Malpura rams possess the adaptive capability to two stresses simultaneously. This is evident from the nonsignificant changes in RR, RT, sweating rate of scrotum and skin and Hb concentration between HS and CS groups. Further, the capability to adjust the cortisol level to minimum possible increase to elicit the heat stress relieving effects also proves the superior adaptive capability of Malpura rams to the effects of combined stresses. Keywords: cortisol, combined stress.ICAR-CSWR

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Not AvailableA study was conducted with the primary objective to establish the influence of body condition scoring on the growth and reproductive performance of Garole x Malpura ewes. The duration of the study was for five months involving 97 adult Garole X Malpura (GM) ewes. The animals were allocated in three groups by body condition score (2.5 BCS; n= 11, BCS 3.0; n=59 and BCS 3.5; n=27). All the animals were kept under semi-intensive management system by subjecting the animals to grazing during day time and housing them in the night. Apart from grazing, ewes were provided with concentrate mixture at the rate of 150 g/day/ewe. The ewes in estrus after 12 h of onset of estrus were hand mated twice at 12 h intervals with a ram of proven fertility in the morning and evening. The pregnancy was confirmed by real time B-mode transabdominal ultrasonography. The experiment was continued until lambing. Under the different BCS, the ewe’s growth and reproductive parameters were assessed. Results: BCS significantly (P<0.05) influenced body weight, heart girth, lambing %, and birth weight of lambs. The highest (P<0.05) body weight was recorded in 3.5 BCS group while the lowest (P<0.05) being in 2.5 BCS group (Table 1). The highest (P<0.05) heart girth was recorded in 3.5 BCS group while the lowest (P<0.05) being in 2.5 BCS group. The highest (P<0.05) lambing rate recorded in 3.0 BCS group while the lowest (P<0.05) was in 2.5 BCS group. Further the highest (P<0.05) birth weight recorded being in 2.5 BCS group. Conclusion: Thus it can be concluded from the study that active management of Garole X Malpura sheep flock to maintain optimum BCS will help to ensure an economically viable production system.Not Availabl