Phyllanthus watsonii Airy Shaw is an endemic plant found in Peninsular Malaysia. Although there are numerous reports on the anti cancer properties of other Phyllanthus species, published information on the cytotoxicity of P. watsonii are very limited. The present study was carried out with bioassay-guided fractionation approach to evaluate the cytotoxicity and apoptosis induction capability of the P. watsonii extracts and fractions on human gynecologic (SKOV-3 and Ca Ski) and colon (HT-29) cancer cells. P. watsonii extracts exhibited strong cytotoxicity on all the cancer cells studied with IC50 values of ≤ 20.0 µg/mL. Hexane extract of P. watsonii was further subjected to bioassay-guided fractionation and yielded 10 fractions (PW-1→PW-10). PW-4→PW-8 portrayed stronger cytotoxic activity and was further subjected to bioassay-guided fractionation and resulted with 8 sub-fractions (PPWH-1→PPWH-8). PPWH-7 possessed greatest cytotoxicity (IC50 values ranged from 0.66 – 0.83 µg/mL) and was selective on the cancer cells studied. LC-MS/MS analysis of PPWH-7 revealed the presence of ellagic acid, geranic acid, glochidone, betulin, phyllanthin and sterol glucoside. Marked morphological changes, ladder-like appearance of DNA and increment in caspase-3 activity indicating apoptosis were clearly observed in both human gynecologic and colon cancer cells treated with P. watsonii especially with PPWH-7. The study also indicated that P. watsonii extracts arrested cell cycle at different growth phases in SKOV-3, Ca Ski and HT-29 cells. Cytotoxic and apoptotic potential of the endemic P. watsonii was investigated for the first time by bioassay-guided approach. These results demonstrated that P. watsonii selectively inhibits the growth of SKOV-3, Ca Ski and HT-29 cells through apoptosis induction and cell cycle modulation. Hence, P. watsonii has the potential to be further exploited for the discovery and development of new anti cancer drugs.

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Atherosclerosis is an impairment of the artery walls made up of two membrane layers, intima and media. Oxidative stress, hypertension, and hypercholesterolemia are the three main factors that cause atherosclerosis. These conditions are frequently found together and may cause atherogenesis to rapidly occur. The edible genus Pleurotus is commonly known as oyster mushrooms. Pleurotus spp. has been proven to have valuable medicinal attributes. Hence, they have been listed among "mushroom nutriceuticals" and categorized as both functional foods and medicinal mushrooms. In this review, we report the benefits of Pleurotus spp. for the prevention and treatment of atherosclerosis via reduction of oxidative stress, hypertension, and hypercholesterolemia in terms of the therapeutic compounds responsible. This review revealed that at least ten different types of Pleurotus spp. have been reported to have anti-atherogenic capabilities, with six of them possessing high levels of anti-atherogenic compounds such as ACE inhibitor peptide, ergothioneine, chrysin, and lovastatin. Hence, it has been demonstrated that Pleurotus spp. has great potential for use as food or extracts from fruiting bodies or mycelium in an alternative therapy for atherosclerosis, through prevention and treatment of oxidative stress, hypertension, and hypercholesterolemia.

The polysaccharide fraction from Solanum nigrum Linne has been shown to have antitumor activity by enhancing the CD4+/CD8+ ratio of the T-lymphocyte subpopulation. In this study, we analyzed a polysaccharide extract of S. nigrum to determine its modulating effects on RAW 264.7 murine macrophage cells since macrophages play a key role in inducing both innate and adaptive immune responses. Crude polysaccharide was extracted from the stem of S. nigrum and subjected to ion-exchange chromatography to partially purify the extract. Five polysaccharide fractions were then subjected to a cytotoxicity assay and a nitric oxide production assay. To further analyze the ability of the fractionated polysaccharide extract to activate macrophages, the phagocytosis activity and cytokine production were also measured. The polysaccharide fractions were not cytotoxic, but all of the fractions induced nitric oxide in RAW 264.7 cells. Of the five fractions tested, SN-ppF3 was the least toxic and also induced the greatest amount of nitric oxide, which was comparable to the inducible nitric oxide synthase expression detected in the cell lysate. This fraction also significantly induced phagocytosis activity and stimulated the production of tumor necrosis factor-α and interleukin-6. Our study showed that fraction SN-ppF3 could classically activate macrophages. Macrophage induction may be the manner in which polysaccharides from S. nigrum are able to prevent tumor growth.

SummaryThis paper reports on the vinca alkaloid produced by a novel Nigrospora sphaerica isolated from Catharanthus roseus. Through liquid chromatography–mass spectrometry (LCMS), only the crude mycelia extract of this fungus was positive for determination of vinblastine. This vinca alkaloid was then purified by using high‐performance liquid chromatography (HPLC) and tested for cytotoxicity activity using MTT assays. The breast cell line cancer (MDA‐MB 231) was treated with a purified vinblastine which was intracellulary produced by N. sphaerica. The purified vinblastine from extracted leaf of C. roseus was used as a standard comparison. A positive result with a value of half maximal inhibitory concentration (IC 50) of > 32 μg ml−1 was observed compared with standard (IC 50) of 350 μg ml−1 only. It showed that a vinblastine produced by N. sphaerica has a high cytotoxicity activity even though the concentration of vinblastine produced by this endophytic fungus was only 0.868 μg ml−1.