Anti-proliferation of MDA-MB-231 cells by Averrhoa bilimbi extract is associated with G0/G1 perturbation and mitochondria-mediated apoptosis independent of p53

Practiced as folk medicine since ancient times, bilimbi (Averrhoa bilimbi) is commonly consumed and widely cultivated in Malaysia. In search for naturally occurring anticancer agents, a potential fruit extract was found to exert anticancer properties in vitro without any cytotoxic effect on normal cells. This study investigated the anti-proliferative effect and underlying cell death pathway induced by bilimbi ethanolic extract on human non-hormone-dependent breast cancer cell line, MDA-MB-231. Anticancer potential of bilimbi extract was conducted by investigating the in vitro growth inhibitory effect, DNA fragmentation, cell cycle progression and anti-proliferation assay. Release of caspases, cytochrome c and apoptotic proteins were demonstrated to determine the mechanism of cell death pathway. Findings revealed that bilimbi inhibited growth of MDA-MB-231 cells through the induction of apoptosis mediated by cell cycle arrest at G0/G1 checkpoint. Released of cytochrome c coupled with up-regulation of caspase-3/7, caspase-9 and Bax pro-apoptotic proteins in addition to down-regulation of dysfunctional p53 and Bcl-2 anti-apoptotic proteins implied that bilimbi induced a p53-independent mitochondrial apoptosis pathway in MDA-MB-231. These results suggest that bilimbi could induce tumor cell anti-proliferation through apoptosis. As a natural product, bilimbi could be a promising anticancer agent and an inexpensive approach to cancer chemoprevention strategy

Comparison of total phenolic contents and antioxidant activities of turmeric leaf, pandan leaf and torch ginger flower

Synthetic antioxidants are added to food in the powdered form to preserve it. However these compounds posed serious health concern since they have been associated with causing cancer. Thus using fresh herbs with antioxidant activities would be good alternative. The objectives of this study were to evaluate and compare the total phenolic contents and antioxidant activities of both powdered and fresh forms of turmeric leaf, pandan leaf and torch ginger flower. Total phenolic content (TPC) was assayed based on the redox reaction between Folin-Ciocalteu with phenolics in the sample extracts. Antioxidant activity (AA) was assayed using the ß-carotene linoleate model system and the percentage of antioxidant activity was calculated from the values of degradation rate. Scavenging activity (SA) was assayed using the DPPH radical scavenging model system whereby EC50 value was determined from the plotted graph of scavenging activity against the concentration of sample extracts. Analyses revealed that powdered forms of turmeric leaf, pandan leaf and torch ginger flower had higher TPC (2013.09 ± 5.13, 1784.25 ± 7.59 and 1937.42 ± 6.61 mg GAE/100g, respectively) than their respective fresh forms (348.75 ± 1.26, 356.42 ± 1.32 and 211.59 ± 6.29 mg GAE/100g, respectively). Similarly, powdered forms of turmeric leaf, pandan leaf and torch ginger flower possessed better AA (64.31 ± 0.99, 65.09 ± 0.74 and 11.80 ± 0.40 %, respectively) than their respective fresh forms (24.93 ± 0.71, 16.91 ± 0.70 and 1.45 ± 0.10 %, respectively). Powdered forms of turmeric leaf, pandan leaf and torch ginger flower were also better radical scavenger as compared to their respective fresh forms. In conclusion, all samples in their powdered forms have high total phenolic contents, antioxidant and scavenging activities than their respective fresh forms

Variability in nutritional composition and phytochemical properties of red pitaya (Hylocereus polyrhizus) from Malaysia and Australia

The present work sought to investigate the nutritional composition and phytochemical properties of red pitaya (Hylocereus polyrhizus) juices from Malaysia and Australia and to determine the optimum ethanol concentration (in the range of 0-100% ethanol) for the extraction of phenolic, flavonoid and betacyanin contents. The predominant macronutrient in red pitaya juice was carbohydrate while potassium and vitamin A were the major mineral and vitamin content. Red pitaya juice from Malaysia achieved optimal total phenolic content at 20% of ethanol (20mL ethanol in 100mL water, v/v); total flavonoid content at 60% (v/v); and betacyanin content at 0% (v/v). Red pitaya juice from Australia achieved the maximum total phenolic content at 60% (v/v); total flavonoid content at 20% (v/v); and betacyanin content at 80% (v/v). Nutritional composition and the phytochemical properties of red pitaya in Malaysia and Australia were significantly different suggested the role of environmental factors like soil and climate on the phytochemical properties of red pitaya

Chemical composition and antioxidant activity of Strobilanthes crispus leaf extract

This study investigated the components present in and the total antioxidant activity of leaves of Strobilanthes crispus (L.) Bremek or Saricocalyx crispus (L.) Bremek (Acanthacea). Proximate analyses and total antioxidant activity using ferric thiocyanate and thiobarbituric acid methods were employed. Minerals content was determined using the atomic absorption spectrophotometer, whereas the water-soluble vitamins were determined by means of the UV-VIS spectrophotometer (vitamin C) and fluorimeter (vitamins B1 and B2). Catechin, tannin, caffeine, and alkaloid contents were also studied. All data were compared to the previously reported results of Yerbamate, green tea, black tea, and Indian tea. The dried leaves contained a high amount of total ash (21.6%) as a result of a high amount of minerals including potassium (51%), calcium (24%), sodium (13%), iron (1%), and phosphorus (1%). High content of water-soluble vitamins (C, B1, and B2) contributed to the high antioxidant activity of the leaves. The leaves also contained a moderate amount of other proximate composition as well as other compounds such as catechins, alkaloids, caffeine, and tannin, contributing further to the total antioxidant activity. Catechins of Strobilanthes crispus leaves showed highest antioxidant activity when compared to Yerbamate and vitamin E. Consumption of the leafy extract daily (5 g/day) as an herbal tea could contribute to the additional nutrients and antioxidants needed in the body to enhance the defense system, especially toward the incidence of degenerative diseases

Evaluation of total phenolic content, total antioxidant activity, and antioxidant vitamin composition of pomegranate seed and juice

This study aimed to determine total phenolic content (TPC), total antioxidant activity (TAA), antioxidant vitamin composition (A, C, and E) of pomegranate fruit. In addition, two edible parts of pomegranate juice, pomegranate seed, and combination of them were compared based on antioxidant properties. TPC was determined by using Folin-Ciocalteu (FC) method based on colorimetric reduction. Ferric reduction ability power (FRAP assay) was used to test the antioxidant activity. Vitamin assessments were conducted by using high performance liquid chromatography (HPLC). Results for antioxidant vitamin composition in pomegranate juice (PJ) showed that the concentration of vitamin A was 22.8 ± 0.69 μg/100 g, vitamin C was 57.8 ± 0.59 mg/100 g, and vitamin E was 0.07 ± 0.01 mg/100 g. Besides, TPC in PJ, pomegranate seed (PS), and pomegranate seed-juice (PSJ) was 2502 ± 54, 165 ± 49, and 2696 ± 49 mg GAE/L, and TAA was 32 ± 5.1, 20 ± 2.8, and 47 ± 5.5 mmol/L respectively. This study revealed that PSJ contained high level of phenolic compounds, antioxidant activity, and vitamin C. In addition, TPC was as main contributor to antioxidant activities, and positively correlated with TAA (r2 = 0.91, p < 0.05). Therefore, combination of pomegranate seed and juice may become an alternative and potential source of natural antioxidant

Identification and concentration of some flavonoid components in Malaysian young ginger (Zingiber officinale Roscoe) varieties by a high performance liquid chromatography method.

Flavonoids make up one of the most pervasive groups of plant phenolics. Due to their importance in plants and human health, it would be useful to have a better understanding of flavonoid concentration and biological activities that could indicate their potentials as therapeutic agents, and also for predicting and controlling the quality of medicinal herbs. Ginger (Zingiber officinale Roscoe) is a famous and widely used herb, especially in Asia, that contains several interesting bioactive constituents and possesses health promoting properties. In this study, total flavonoids and some flavonoid components including quercetin, rutin, catechin, epicatechin, kaempferol and naringenin were extracted from the leaves and rhizomes of two varieties of Zingiber officinale (Halia Bentong and Halia Bara) at three different growth points (8, 12 and 16 weeks after planting), and analyzed by a high performance liquid chromatography (HPLC) method in order to determine the potential of the subterranean part of the young ginger. The results showed that Halia Bara had a higher content of flavonoids in the leaves and rhizomes as compared to Halia Bentong. In both varieties, the concentration of flavonoids in the leaves decreased (Halia Bentong, 42.3%; Halia Bara 36.7%), and in the rhizomes it increased (Halia Bentong 59.6%; Halia Bara 60.1%) as the growth period increased. Quercetin was abundant in both varieties. The antioxidant activity determined by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay showed high activities (65.7%) in the leaves of Halia Bara at 8 weeks after planting. Results suggested a good flavonoid content and antioxidant activity potential in ginger leaves at 8 weeks after planting. The leaves of these ginger varieties could be useful for both food flavourings and in traditional medicine

Effect of cacao liquor extract on tumor marker enzymes during chemical hepatocarcinogenesis in rats.

This study investigated the effect of cacao liquor extract (CLE) on tumor marker enzymes-alkaline phosphatase (ALP), γ-glutamyl transpeptidase (GGT), glutathione-S-transferase (GST), and glutathione reductase (GR) activities-in plasma and/or liver of hepatocarcinogenic rats, which were induced with diethylnitrosamine and 2-acetylaminofluorene. Twenty-nine male Sprague-Dawley rats (weighing 150-330 g) were divided into four groups (n = 6-8): normal control group (N), normal group + CLE (NE), cancer group (C), and cancer group + CLE (CE). Analysis of variance showed significant differences (P < .05) in the specific activities of ALP, GGT, and GST between the C and N groups. However, GR activity for the C group was not significantly different compared with the N group. In the CE group, the specific activities of ALP, GGT, GST, and GR were significantly lower (P < .05) compared with the C group. The findings showed that CLE could lower the activity of tumor marker enzymes of rats during hepatocarcinogenesis. Based on the results obtained, polyphenol compounds present in the cacao liquor, extracted by using ethanol, have the potential in decreasing the severity of hepatocarcinogenesis

Do managers reappoint auditor for related party transactions? Evidence from selected East Asian countries

We study the association between auditor reappointment (initial relationship stage), including recurring auditor appointment over several consecutive years (close relationship stage) and company engagement in related-party transactions (RPTs) for selected listed companies from Hong Kong, Malaysia, Singapore and Thailand. The results show that auditor reappointment has significant and negative associations with company engagement in RPTs. By contrast, the close ACR relationship increases company engagement in RPTs. The evidence also suggests that Big 4 audit firms can reduce company engagement in RPTs, even when they have a close relationship. However, the findings derived from a sub-sample of RPT companies suggest that the close relationship between Big 4 audit firms and their clients substantially encourages companies to engage in RPTs. Overall, these findings are consistent with theories in which higher audit quality is effective at monitoring RPTs, but the established relationship looks likely to create conflicting opinions that impair auditors’ independent judgment. Nevertheless, the likelihood of conflict disappears when clients operate in countries that more effectively implement and enforce regulations and protect minority shareholders

Elevated carbon dioxide increases contents of flavonoids and phenolic compounds, and antioxidant activities in Malaysian young ginger (Zingiber officinale Roscoe.) varieties.

Zingiber officinale Roscoe. (Family Zingiberaceae) is well known in Asia. The plant is widely cultivated in village gardens in the tropics for its medicinal properties and as a marketable spice in Malaysia. Ginger varieties are rich in physiologically active phenolics and flavonoids with a range of pharmacological activities. Experiments were conducted to determine the feasibility of increasing levels of flavonoids (quercetin, rutin, catechin, epicatechin, kaempferol, naringenin, fisetin and morin) and phenolic acid (gallic acid, vanillic acid, ferulic acid, tannic acid, cinnamic acid and salicylic acid), and antioxidant activities in different parts of Malaysian young ginger varieties (Halia Bentong and Halia Bara) with CO2 enrichment in a controlled environment system. Both varieties showed an increase in phenolic compounds and flavonoids in response to CO2 enrichment from 400 to 800 μmol mol-1 CO2. These increases were greater in rhizomes compared to leaves. High performance liquid chromatography (HPLC) results showed that quercetin and gallic acid were the most abundant flavonoid and phenolic acid in Malaysian young ginger varieties. Under elevated CO2 conditions, kaempferol and fisetin were among the flavonoid compounds, and gallic acid and vanillic acid were among the phenolic compounds whose levels increased in both varieties. As CO2 concentration was increased from 400 to 800 μmol mol-1, free radical scavenging power (DPPH) increased about 30% in Halia Bentong and 21.4% in Halia Bara; and the rhizomes exhibited more enhanced free radical scavenging power, with 44.9% in Halia Bentong and 46.2% in Halia Bara. Leaves of both varieties also displayed good levels of flavonoid compounds and antioxidant activities. These results indicate that the yield and pharmaceutical quality of Malaysian young ginger varieties can be enhanced by controlled environment production and CO2 enrichmen

Effects of Strobilanthes crispus tea aqueous extracts on glucose and lipid profile in normal and streptozotocin-induced hyperglycemic rats.

Strobilanthes crispus (Acanthaceae) has been used traditionally as antidiabetic, diuretic, antilytic, and laxative and has been proven scientifically to possess high antioxidant activity, anti-AIDS, and anticancer properties. It is commonly consumed in the form of herbal tea. The ethnopharmacological value of this plant, such as the development of nutraceutical S. crispus herbal tea (fermented and unfermented) and assessment of their antihyperglycemic properties were investigated. The antidiabetic properties of S. crispus fermented and unfermented tea was carried out in normal and streptozotocin-induced hyperglycaemic rats for 21 days. Glucose and lipid profile (total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol) were determined at day 0 (baseline), day 7, and day 21. The results showed that the hot water extract of both fermented and unfermented S. crispus tea reduced blood glucose in hyperglycaemic rats. S. crispus unfermented tea also reduced glucose level in normal rat. Both fermented and unfermented S. crispus tea also showed to improve lipid profile. Antioxidant and polyphenol content that present in the extracts might contribute to the antihyperglycemic and antilipidemic properties. Further study is needed to be carried out in pre-clinical and clinical environment to prove its efficacy in human