Several families of ascidians are known to accumulate extremely high levels of vanadium in their blood cells. The concentration of vanadium has been determined in each species; the highest concentration, found in Ascidia gemmata, reaches 350 mM, corresponding to 10 7 times that of sea water. How and why ascidians accumulate vanadium in a highly selective manner and at such extremely high levels have yet to be determined. To address these questions, our research group sought to identify the genes and proteins responsible for the accumulation and reduction of vanadium in vanadocytes, a type of blood cell, as well as the process of vanadium transport from sea water to blood cells through the branchial sac, intestine, and blood plasma. Here, we review the accumulation steps as a system, especially those related to the concentration and chemical species of vanadium at each step. A comprehensive analysis on each organ has already revealed several categories of protein families, such as vanadium-binding proteins and vanadium transporters. Herein, we also discuss the mechanisms by which ascidians selectively accumulate vanadium ions from a biochemical viewpoint.

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Isolation of naturally occurring bacterial strains from metal-rich environments has gained popularity due to the growing need for bioremediation technologies. In this study, we found that the vanadium concentration in the intestine of the vanadium-rich ascidian Ascidia sydneiensis samea could reach 0.67 mM, and thus, we isolated vanadium-resistant bacteria from the intestinal contents and determined the ability of each bacterial strain to accumulate vanadium and other heavy metals. Nine strains of vanadium-resistant bacteria were successfully isolated, of which two strains, V-RA-4 and S-RA-6, accumulated vanadium at a higher rate than did the other strains. The maximum vanadium absorption by these bacteria was achieved at pH 3, and intracellular accumulation was the predominant mechanism. Each strain strongly accumulated copper and cobalt ions, but accumulation of nickel and molybdate ions was relatively low. These bacterial strains can be applied to protocols for bioremediation of vanadium and heavy metal toxicity.

Medicinal plants have been used for treating many kinds of illness due to their safety, cheap and easy to be accessed by all level of society. This study was aimed to determine the effect of the dosage forms (fresh, boiled and ethanol extracted) and the duration (24 and 42 days) of medicinal plant Centella asiatica to the levels of superoxide dismutase (SOD), malondialdehyde (MDA) and the histopathology of diabetic rat brain. The results showed that administration of various dosage forms of C. asiatica were able to increase the number of pyramid cells and neuroglia in the cerebrum significantly (P <0.01) but had no significant effect (P>0.01) at the administration length and the interaction between both treatments. This finding resulted in the new traditional herbal medicine that can be used for treating degenerative disorders on nervous system.

Antifertility agents with safety and effectiveness in terms of minimum side effects have always been a subject of debate. Many studies have been conducted on plants to observe the antifertility effect, but majority of them were toxic. Centella asiatica and Plucea indica leaves have been traditionally used as medicine for its properties to promote antifertility effect. The objective of the present study was to investigate the combination effects of C. asiatica and P. indica leaf extract to the number of follicles, antioxidant activity, and hormonal profile of female rats. Thirty two fertile female rats (2 months), were divided into six groups and treated with different formula of the combination of C. asiatica and P. indica leaf extract: group 1 (T1) with 25 + 25 mg/kg bw, group 2 (T2) with 50 + 50 mg/kg bw, group 3 (T3) with 75 + 75 mg/kg bw, group 4 (T4) with 125 + 125 mg/kg bw, (T5) group 5 with 200 + 200 mg/kg bw, and control group (T0) treated with only 0,5% Na CMC. They were also fed for 42 days. The rat's blood serum was taken for hormonal analysis, as well they were sacrificed and the ovarium were removed for histological and antioxidant analysis. The results revealed that C. asiatica and P. indica leaf extract influences to the number of follicles, antioxidant activity and hormonal profile of the rats. Group 4 (T4) showed the highest antifertility effect on the ovulation number (corpus lutium), total of ovarian follicles, and level of estrogen, respectively. Group 5 (T5) showed the highes level of superoxide dismutase (SOD) and the lowest level of Malondialdehide (MDA). It is concluded that C. asiatica and P. indica exhibited antifertility effects on reproductive system of the female rats.