ABSTRACT
In malaria, development of resistance towards artemisinin derivatives has urged the need for new drugs or new drug combinations to tackle the drug resistant malaria. We studied the fresh root extract of Vetiver zizanioides (Linn.) Nash (VET) with a CDRI-CIMAP antimalarial α/β arteether (ART) together for their antimalarial potential. Our results showed additive to synergistic antimalarial activity of VET and ART with sum fractional inhibitory concentrations Σ FICs 1.02±0.24 and 1.12±0.32 for chloroquine sensitive (CQS) and chloroquine resistant (CQR) strain of Plasmodium falciparum (William H. Welch), respectively. Further, these combinations were explored against multidrug resistant rodent malaria parasite i.e. P. yoelii nigeriensis. Analysis of in vivo interaction of ART and VET showed that 10 mg/kg×5days of ART with 1000 mg/kg of VET ×5 days cured 100% mice infected with MDR parasite, while the same dose of ART could produce only up to 30% cure and VET fraction was not curative at all. Synergism/additiveness, found between VET and ART is reported for the first time. The curative dose of ART in the combination was reduced to its one fourth, and thus limits the side effects, if any. Although antimalarial potential of ART was enhanced by VET, action mechanism of later needs to be elucidated in detail.
ABSTRACT
Background: Vetiveria zizanioides (VZ) (family: Poaceae), an aromatic plant commonly known as “Vetiver” has been used for various ailments. Concerning the various ailments being listed as the traditional uses of VZ, no mention about anxiety and memory was found. Objective: The present study examined the anxiolytic and memory enhancing activity of ethanolic extract of V. zizanioides (EEVZ) dried roots in mice. Materials and Methods: Activity of EEVZ was assessed using models of anxiety (elevated plus‑maze [EPM], light/dark test, hole board test, marble‑burying test) and learning and memory (EPM, passive shock avoidance paradigm). Results: EEVZ at doses of 100, 200, and 300 mg/kg b.w. illustrated significant anxiolytic activity indicated by increase in time spent and number of entries in open arm, time spent in lightened area, number of head poking and number marble buried when compared to that of diazepam (1 mg/kg b.w.), a reference standard. The same treatment showed a significant decrease in transfer latency to reach open arm, shock‑free zone, and number of mistakes when compared to that of scopolamine (0.3 mg/kg b.w.). EEVZ in all the doses (100, 200, and 300 mg/kg b.w.) significantly decreased mortality in sodium nitrite (250 mg/kg b.w.) induced hypoxia and also significantly increases contraction induced by acetylcholine on rat ileum preparation. Conclusion: The result emanated in the present investigation revealed EEVZ possesses significant anxiolytic and nootropic activity by possibly interplaying with neurotransmitters implicated in anxiety and learning and memory.
ABSTRACT
Chrysopogon zizanioides (L.) Roberty, Poaceae, is a plant widely used in northeast Brazil in folk medicine for the treatment of various pathological conditions, including inflammatory pain. The present study evaluated the antinociceptive and anti-inflammatory effects of C. zizanioides essential oil (EO) in rodents. EO was further characterized by GC/MS. The major components of EO were identified as khusimol (19.57%), E-isovalencenol (13.24%), α-vetivone (5.25%), β-vetivone (4.87%) and hydroxy-valencene (4.64%). Following intraperitoneal injection (i.p.), EO at 50 and 100 mg/kg significantly reduced the number of writhes (51.9 and 64.9%, respectively) and the number of paw licks during phase 2 (56.7 and 86.2%, respectively) of a formalin model when compared to control group animals. However, EO-treated mice were ineffective at all doses in hot-plate and rota-rod tests. The EO inhibited the carrageenan-induced leukocyte migration to the peritoneal cavity in a dose-dependent manner (34.7, 35.4, and 62.5% at doses of 25, 50 and 100 mg/kg, respectively). In the paw edema test, the EO (100 mg/kg) inhibited all three phases of the edema equally well, suggesting that the EO has a non-selective inhibitory effect on the release or actions of these mediators. Our results suggest possible antinociceptive and anti-inflammatory effects of the EO.
ABSTRACT
Experiments were conducted to evaluate lead tolerance and accumulation in vetiver grass Vetiveria zizanioides (L.), grown in hydroponics and a pot study and to examine the effect of lead on vetiver oil production. Elevated concentrations of lead decreased the length of shoots and roots of plants. However, vetiver grown in highly contaminated soils showed no apparent phytotoxicity symptoms. Lead concentrations in the shoots and roots of vetiver plants grown in hydroponics were up to 144 and 19530 mg kg-1 and those grown in soil were 38 and 629 mg kg-1, respectively. Lead had an effect on vetiver oil production and composition by stimulating oil yield and the number of its constituents. Oil yield ranged from 0.4-1.3%; the highest yields were found in plants grown in nutrient solution with 100 mg Pb l-1 for 5 weeks (1.29%) and 7 weeks (1.22%). The number of total constituents of vetiver oil also varied between 47-143 compounds when lead was present in the growth medium. The highest number (143) was found in plants grown in soil spiked with 1000 mg Pb kg-1. The predominant compound was khusimol (10.7-18.1%) followed by (E)-isovalencenol (10.3-15.6%). Our results indicated that lead could increase the oil production of vetiver.