Phytochemical analysis and evaluation of antioxidant and antimycobacterial activity of Colletia paradoxa from Brazil.

Colletia paradoxa (Spreng.) Esc. (Rhamnaceae, Colletieae) is a medicinal plant, threatened with extinction in Brazil, presenting great morphological variability. Our objective is to investigate the phytochemical components, antioxidant capacity and antimycobacterial activity of different morphotypes of C. paradoxa in different environments. For this, the crude extract of the leaves and branches of the individuals sampled was used. The elimination capacity of the free radicals was determined by the DPPH method, the antimycobacterial activity by the broth microdilution method and the phenolic content by the spectrophotometric method using the Folin-Ciocalteu reagent and by HPLC. The extracts of C. paradoxa and its morphotypes showed significant amounts of phenolic compounds, including quercetin, quercitrin and rutin, besides considerable antioxidant and antimycobacterial activity No connection was detected between the phytochemical composition and different morphotypes of C. paradoxa.

Hepatoprotective activity and phenolic profile of Zanthoxylum alatum Roxb. fruit extract.

Zanthoxylum alatum Roxb. (Rutaceae) is a medicinal plant, which abundantly grows in the hilly areas of Pakistan. In the present study, the hepatoprotective activity of the Z. alatum whole fruit was evaluated. The hepatoprotective effect of the aqueous extracts was studied on mice liver damage using a single dose of paracetamol (640 mg/kg) orally by monitoring biochemical parameters. Pre-treatment of mice with Z. alatum (100 mg/kg) aqueous extract orally for four days prevented the paracetamol induced rise in serum transaminases (ALT and AST), restored the altered levels of antioxidant enzyme (catalase), thiobarbituric acid reactive substances (TBARS), non-protein thiol and ascorbic acid to near normal levels. The major phenolic acids, some flavonoid aglycone and glycosides were identified in fruit by high performance liquid chromatography. Ellagic acid (24.57±0.01mg/g), chlorogenic acid (10.65±0.01mg/g), gallic acid (9.15±0.02mg/g), chrysin (16.81±0.03), quercetin (16.81±0.03mg/g) and epicatechin (10.93±0.01) were prédominant in infusion of Z. alatum. The result substianted the hepatoprotective activity of Z. alatum which may be associated with its potential use in liver disease.

Evaluation of basil extract ( Ocimum basilicum L. ) on oxidative, anti-genotoxic and anti-inflammatory effects in human leukocytes cell cultures exposed to challenging agents

ABSTRACT Ocimum is one of the most important genera of the Lamiaceae family. Several studies about basil and its popular use reveal many characteristics of the herb, including its use as antioxidant, anti-aging, anti-inflammatory, anti-carcinogenic, anti-microbial, and cardiovascular agents, among others. In this paper, we evaluated genotoxic, oxidative, and anti-inflammatory parameters from the extract of Ocimum basilicum in different concentrations, using human leukocytes cultures exposed to challenging agents. Our results confirm that the O. basilicum extract acts as an antioxidant and effectively reverts or subjugates the effects of high oxidizing agents such as hydrogen peroxide. These actions are attributed to its composition, which is rich in polyphenols and flavonoids as well as compounds such as rosmarinic acid, all of which have well-known antioxidant activity. We also show that our basil extract presents anti-inflammatory properties, the mechanism of which is a composed interaction between the inhibition of pro-inflammatory mediator and the stimulation of anti-inflammatory cytokines. Although pharmacodynamics studies are necessary to evaluate the activities in vivo, our results demonstrated that basil could act as an antioxidant and anti-inflammatory and a possible alternative for medicinal treatment.

Antinociceptive and anti-inflammatory effect of the Scutia buxifolia Reissek stem barks extract.

BACKGROUND: Scutia buxifolia (Rhamnaceae) has been extensively studied for its phenolics groups, which are able to capture free radicals; being therefore, considered promising as an antioxidant in preventing diseases resulting from oxidative stress. HYPOTHESIS: Scutia buxifolia extract (SBE) presents antinociceptive and anti-inflammatory effect in mice. STUDY DESIGN: SBE (400-800mg/kg) was tested in different pain models to investigate its antinociceptive and anti-inflammatory action. METHODS: It was carried out the abdominal writhing test, capsaicin test, thermal hyperalgesia and incisional pain. The inflamed tissue by carrageenan was used for the analysis of interleukins (IL), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), c-reactive protein (CRP), nitrite and nitrate (NOx) determination and myeloperoxidase (MPO) activity. Furthermore, we evaluate the possible action mechanism of SBE using naloxone in capsaicin test. RESULTS: SBE prevented the nociception caused by acetic acid, formalin and capsaicin test. However, neither the SBE prevented the thermal hyperalgesia in hot-plate test, nor the naloxone reversed the SBE antinociceptive effect in capsaicin test. Furthermore, the administration of SBE prevented significantly the increase of MPO activity, the NOx content, and the levels of IL-1, IL-6, TNF-α, INF-γ and CRP and was able to increase the IL-10 levels after the inflammation induced by carrageenan in mice. In addition, SBE prevented mechanical hyperalgesia in a postoperative pain model. CONCLUSION: The SBE presents great antinociceptive and anti-inflammatory activity in mice but this effect not seem to have its action mechanism like opioids. It is possible that its antinociceptive effects are associated with levels decrease of inflammatory mediators.

Tabernaemontana catharinensis ethyl acetate fraction presents antinociceptive activity without causing toxicological effects in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Tabernaemontana catharinensis (Apocynaceae) is a medicinal plant used for the treatment of painful and inflammatory disorders. Here, we investigated the antinociceptive potential of the ethyl acetate fraction (Eta) from T. catharinensis leaves and assessed its toxic effects in mice to validate its popular use. MATERIALS AND METHODS: Adult male Swiss mice (30-35g) were used. The Eta antinociceptive effect (200-800mg/kg, oral route (p.o.)) was evaluated in the acetic acid, formalin, capsaicin and tail-immersion tests. Adverse effects were analyzed using rotarod and open-field tests, body temperature, biochemical analysis and gastric lesions assessment. To evaluate the acute (OECD 423) or sub-acute (OECD 407) toxicity of the Eta, it was administered orally at a single (2000mg/kg) or repeated doses (100-400mg/kg/day for 28 days), respectively. Mortality, behavioral changes, biochemical and hematological parameters were evaluated. The Eta effect on cellular viability also was evaluated. RESULTS: Eta (200-800mg/kg) inhibited the nociception caused by acetic acid (93.9±1.5%), formalin (86.2±10.8%) or capsaicin (75.4±3.3%) without inducing gastric lesions. Moreover, Eta neither altered the body temperature, biochemical parameters, nor forced or spontaneous locomotor activity of mice. The acute administration of the Eta (2000mg/kg) promoted a decrease in blood glucose levels and alanine aminotransferase activity. In the sub-acute toxicity study, Eta increased the aspartate aminotransferase activity (400mg/kg) and platelet distribution width (200mg/kg). Furthermore, Eta did not alter the cellular viability in cortical slices. CONCLUSIONS: Eta presents antinociceptive effects and mild toxicity in mice. These results support its traditional use as a potential analgesic.

Guava leaves polyphenolics-rich extract inhibits vital enzymes implicated in gout and hypertension in vitro.

BACKGROUND/AIM: Elevated uric acid level, an index of gout resulting from the over-activity of xanthine oxidase (XO), increases the risk of developing hypertension. However, research has shown that plant-derived inhibitors of XO and angiotensin 1-converting enzyme (ACE), two enzymes implicated in gout and hypertension, respectively, can prevent or ameliorate both diseases, without noticeable side effects. Hence, this study characterized the polyphenolics composition of guava leaves extract and evaluated its inhibitory effect on XO and ACE in vitro. MATERIALS AND METHODS: The polyphenolics (flavonoids and phenolic acids) were characterized using high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). The XO, ACE, and Fe(2+)-induced lipid peroxidation inhibitory activities, and free radicals (2,2-diphenylpicrylhydrazyl [DPPH]* and 2,2´-azino-bis-3-ethylbenzthiazoline-6-sulphonic [ABTS]*(+)) scavenging activities of the extract were determined using spectrophotometric methods. RESULTS: Flavonoids were present in the extract in the order of quercetin > kaempferol > catechin > quercitrin > rutin > luteolin > epicatechin; while phenolic acids were in the order of caffeic acid > chlorogenic acid > gallic acids. The extract effectively inhibited XO, ACE and Fe(2+)-induced lipid peroxidation in a dose-dependent manner; having half-maximal inhibitory concentrations (IC50) of 38.24 ± 2.32 µg/mL, 21.06 ± 2.04 µg/mL and 27.52 ± 1.72 µg/mL against XO, ACE and Fe(2+)-induced lipid peroxidation, respectively. The extract also strongly scavenged DPPH* and ABTS*(+). CONCLUSION: Guava leaves extract could serve as functional food for managing gout and hypertension and attenuating the oxidative stress associated with both diseases.

Phytochemical Composition, Antifungal and Antioxidant Activity of Duguetia furfuracea A. St.-Hill.

UNLABELLED: Background. Duguetia furfuracea is popular plant used in popular medicine. Hypothesis/Purpose. This claim evaluated the phytochemical composition of the hydroethanolic extract (HEDF), fractions of Duguetia furfuracea, and antioxidant and antifungal activity. Methods. The chemical profile was carried out by HPLC-DAD. The total phenolic contents and flavonoid components were determined by Folin-Ciocalteu and aluminium chloride reaction. The antioxidant activity was measured by scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and ferric reducing ability of plasma (FRAP) methods. The antifungal activity was determined by microdilution assay. RESULTS: HPLC analysis revealed caffeic acid and rutin as major compounds (HEDF), caffeic acid and quercitrin (Mt-OH fraction), and quercitrin and isoquercitrin (Ac-OEt fraction). The highest levels of phenols and total flavonoids were found for Ac-OEt fraction, and the crude extract showed higher in vitro antioxidant potential. The antifungal activity showed synergic effect with fluconazole and EHDF against C. krusei, fluconazole and Mt-OH against C. krusei and C. tropicalis, and Ac-OE and fluconazole against C. albicans. Conclusion. The highest levels of phenols and total flavonoids were marked with antioxidant effect. This is the first report of bioactivity of the synergic effect of HEDF and fractions. More studies would be required to better clarify its mechanism of synergic action.

Effect of Two Ginger Varieties on Arginase Activity in Hypercholesterolemic Rats.

Recently, ginger has been used in traditional Chinese medicine as an herbal therapy for treating several cardiovascular diseases, however, information on its mechanism of action is limited. The present study assessed the effect of two ginger varieties (Zingiber officinale and Curcuma longa) on the arginase activity, atherogenic index, levels of liver thiobarbituric acid reactive substances (TBARSs), and plasma lipids in rats fed with a high-cholesterol (2%) diet for 14 days. Following the treatment period, it was found that feeding a high-cholesterol diet to rats caused significant (p < 0.05) increases in arginase activity, atherogenic index, levels of TBARS, total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C) with a concomitant decrease in high-density lipoprotein cholesterol (HDL-C). However, both ginger and turmeric (2% and 4%) caused significant (p < 0.05) decreases in arginase activity and the atherogenic index, and prevented hypercholesterolemia by decreasing the TC, TGs, and LDL-C while increasing the HDL-C when compared with the controls. In conclusion, dietary supplementation with both types of rhizomes (ginger and turmeric) inhibited arginase activity and prevented hypercholesterolemia in rats that received a high-cholesterol diet. Therefore, these activities of ginger and turmeric represent possible mechanisms underlying its use in herbal medicine to treat several cardiovascular diseases.

Phenolic composition and antiparasitic activity of plants from the Brazilian Northeast "Cerrado".

This work describes the antiparasitic and cytotoxic activities of three plant species from the Cerrado biome, Northeastern Brazil. Significant antiparasitic inhibition was observed against Trypanosoma cruzi (63.86%), Leishmania brasiliensis (92.20%) and Leishmania infantum (95.23%) when using ethanol extract from leaves of Guazuma ulmifolia Lam. (Malvaceae), at a concentration of 500 µg/mL. However, low levels of inhibition were observed when assessing leishmanicidal and trypanocidal (Clone CL-B5) activities of crude ethanol extracts from leaves and bast tissue of Luehea paniculata (Malvaceae) and leaves and bark of Prockia crucis (Salicaceae) at a concentration of 500 µg/mL. The extracts revealed the presence of phenolic acids such as gallic acid, chlorogenic acid, caffeic acid and rosmarinic acid, as well as flavonoids such as rutin, luteolin, apigenin and quercetin - the latter detected only in G. ulmifolia. G. ulmifolia extract displayed higher leishmanicidal activity probably due to the presence of quercetin, a potent known leishmanicidal compound. A cytotoxicity test indicated values over 50% at the highest concentration (1000 µg/mL) for all natural products, which were considered cytotoxic. This points out the need for further tests to enable future in vivo trials, including antineoplastic activity on human tumor cells.

Effect of Ginger and Turmeric Rhizomes on Inflammatory Cytokines Levels and Enzyme Activities of Cholinergic and Purinergic Systems in Hypertensive Rats.

Inflammation exerts a crucial pathogenic role in the development of hypertension. Hence, the aim of the present study was to investigate the effects of ginger (Zingiber officinale) and turmeric (Curcuma longa) on enzyme activities of purinergic and cholinergic systems as well as inflammatory cytokine levels in Nω-nitro-L-arginine methyl ester hydrochloride-induced hypertensive rats. The rats were divided into seven groups (n = 10); groups 1-3 included normotensive control rats, hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats, and hypertensive control rats treated with atenolol (an antihypertensive drug), while groups 4 and 5 included normotensive and hypertensive (Nω-nitro-L-arginine methyl ester hydrochloride) rats treated with 4 % supplementation of turmeric, respectively, and groups 6 and 7 included normotensive and hypertensive rats treated with 4 % supplementation of ginger, respectively. The animals were induced with hypertension by oral administration of Nω-nitro-L-arginine methyl ester hydrochloride, 40 mg/kg body weight. The results revealed a significant increase in ATP and ADP hydrolysis, adenosine deaminase, and acetylcholinesterase activities in lymphocytes from Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats when compared with the control rats. In addition, an increase in serum butyrylcholinesterase activity and proinflammatory cytokines (interleukin-1 and - 6, interferon-γ, and tumor necrosis factor-α) with a concomitant decrease in anti-inflammatory cytokines (interleukin-10) was observed in Nω-nitro-L-arginine methyl ester hydrochloride hypertensive rats. However, dietary supplementation of both rhizomes was efficient in preventing these alterations in hypertensive rats by decreasing ATP hydrolysis, acetylcholinesterase, and butyrylcholinesterase activities and proinflammatory cytokines in hypertensive rats. Thus, these activities could suggest a possible insight about the protective mechanisms of the rhizomes against hypertension-related inflammation.

Safety assessment and behavioral effects of Solanum guaraniticum leaf extract in rats

ABSTRACT Solanum guaraniticum is a medicinal plant traditionally used to treat gastric and liver diseases. However, there is no documented evidence corroborating its safety. The present study evaluated the potential toxicity of S. guaraniticum leaf extract after acute administration in rats. Single doses of the extract (1.250, 2.500, and 5.000 mg/kg) were administered by gavage, and the rats were then monitored for 48 h and/or 14 days. Mortality, acute signs of toxicity, and general activity in the open field test were assessed as well as hematological and biochemical parameters, enzymatic activity (δ-aminolevulinate dehydratase and acetylcholinesterase), and oxidative stress parameters (lipid peroxidation level, non-protein thiol content, tissue catalase activity, and serum ferrous reducing power). Phytochemical analysis was also performed by HPLC. The results showed that extract administration produced no deaths (LD50 > 5,000 mg/kg), and no significant adverse effects regarding food consumption, body weight gain, gross pathology, or other parameters. However, the open field tests showed a decrease in spontaneous activity (crossing and rearing) mainly at 48 h after treatment. The results suggest that S. guaraniticum extract is not acutely toxic, but causes alterations in central nervous system activity.

RESUMO Solanum guaraniticum é uma planta medicinal tradicionalmente usada para tratar doenças gástricas e hepáticas. Porém, não há evidências documentadas sobre sua segurança. O presente estudo avaliou a toxicidade do extrato das folhas de S. guaraniticum após administração aguda em ratos. Doses únicas do extrato (1.250, 2.500 and 5.000 mg/kg) foram administradas por gavagem e os animais foram monitorados por 48 h ou 14 dias. Mortalidade, sinais de toxicidade aguda e atividade geral, através do teste de campo aberto, foram analisados, assim como parâmetros hematológicos e bioquímicos, atividades enzimáticas (δ-aminolevulinato desidratase e acetilcolinesterase) e parâmetros de estresse oxidativo (nível de peroxidação lipídica, conteúdo de tióis não protéicos, atividade da catalase em tecidos e poder redutor em soro). A análise fitoquímica também foi realizada por HPLC. Os resultados mostraram que a administração do extrato não provoca mortes (LD50>5.000 mg/kg) ou efeitos adversos significativos com relação ao consumo de comida, ganho de peso corporal, análise patológica, entre outros. Entretanto, o teste de campo aberto mostrou uma diminuição na atividade espontânea geral (cruzamentos e levantadas), principalmente em 48 h após o tratamento. Portanto, nossos resultados sugerem que o extrato de S. guaraniticum não é agudamente tóxico, mas causa alterações na atividade do sistema nervoso central.

Protective Effects of Aqueous Extract of Luehea divaricata against Behavioral and Oxidative Changes Induced by 3-Nitropropionic Acid in Rats.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease. Accordingly, 3-nitropropionic acid (3-NP) has been found to effectively produce HD-like symptoms. Luehea divaricata (L. divaricata), popularly known in Brazil as "açoita-cavalo," may act as a neuroprotective agent in vitro and in vivo. We evaluated the hypothesis that the aqueous extract of L. divaricata could prevent behavioral and oxidative alterations induced by 3-NP in rats. 25 adult Wistar male rats were divided into 5 groups: (1) control, (2) L. divaricata (1000 mg/kg), (3) 3-NP, (4) L. divaricata (500 mg/kg) + 3-NP, and (5) L. divaricata (1000 mg/kg) + 3-NP. Groups 2, 4, and 5 received L. divaricata via intragastric gavage daily for 10 days. Animals in groups 3, 4, and 5 received 20 mg/kg 3-NP daily from days 8-10. At day 10, parameters of locomotor activity and biochemical evaluations were performed. Indeed, rats treated with 3-NP showed decreased locomotor activity compared to controls. Additionally, 3-NP increased levels of reactive oxygen species and lipid peroxidation and decreased ratio of GSH/GSSG and acetylcholinesterase activity in cortex and/or striatum. Our results suggest that rats pretreated with L. divaricata prior to 3-NP treatment showed neuroprotective effects when compared to 3-NP treated controls, which may be due to its antioxidant properties.

Antidepressant-Like and Antioxidant Effects of Plinia trunciflora in Mice.

The jaboticaba tree, Plinia trunciflora (O. Berg) Kausel, is popularly named "jabuticabeira" in Brazil and is used in folk medicine to treat diabetes and chronic inflammation of the tonsils, but studies evaluating the central effects of this species are limited. This study evaluated the antidepressant-like and antioxidant effects of P. trunciflora (PT) aqueous extract, in which five different anthocyanins were identified. PT showed significant ferric-reduction power and DPPH radical scavenging activity in vitro and reduced lipid peroxidation both in vitro and ex vivo. At the behavioural level, PT (400 and 800 mg/kg, i.p.) dose-dependently reduced immobility time in the tail suspension test in Swiss male mice. The identification of bioactive compounds accompanied by the in vitro and ex vivo antioxidant activity of PT suggests that these activities might be related to the antidepressant-like activity of P. trunciflora.

Chromatographic analysis, antiproliferative effect and genotoxicity of aqueous extracts of Citrus sinensis (L) osbeck on the Allium cepa L test system / Análise cromatográfica, efeito antiproliferativo e genotoxicidade de extratos aquosos de Citrus sinensis (L) osbeck sobre o sistema teste de Allium cepa L

The species Citrus sinensis (L.) Osbeck (orange) is used in folk medicine as an infusion (tea) for the treatment of nerve irritation, insomnia, spasms, whooping cough, flue, and gastrointestinal problems. The aim of this study was to evaluate the antiproliferative and genotoxic potential of aqueous extracts of C. sinensis testing by Allium cepa L., as well as to determine the components in the complex mixture (tea). Leaves from two populations of this species were used in the preparation of infusions at two concentrations: 6g.L-1 and 24g.L-1, besides using distilled water as a negative control and 9.6% glyphosate as a positive control. Six groups of four bulbs of A. cepa were used, each group corresponding to one of the treatments. The bulbs were rooted in distilled water and then transferred to the respective treatments where they remained for 24 hours (the bulbs of the negative control remained in distilled water). The rootlets were collected, fixated in ethanol-acetic acid (3:1) for 24 hours and stored in 70% alcohol. 4,000 cells were analyzed per group of bulbs, and the calculated mitotic indices were submitted to statistical analysis using the c 2 test. The aqueous extracts of C. sinensis have as main components flavonoids and phenolic acids. The values of the mitotic index decreased with increasing concentration of the extracts relative to the control in water. The results indicated that the orange aqueous extracts in the studied concentrations in both populations have antiproliferative and genotoxic effects on the cell cycle of A. cepa.

A espécie Citrus sinensis (laranjeira) (L.) Osbeck é usada na medicina popular como infusão (chá) para o tratamento de irritações nervosas, insônia, espasmos, tosse convulsa, gripes e problemas gastrointestinais. O objetivo desse estudo foi avaliar o potencial antiproliferativo e genotóxico dos extratos aquosos de Citrus sinensis pelo teste de Allium cepa L., bem como determinar os componentes na mistura complexa (chá). Folhas de duas populações dessa espécie foram utilizadas no preparo das infusões em duas concentrações: 6g.L-1 e 24g.L-1, além de serem usados água destilada como controle negativo e glifosato 9,6% como controle positivo. Utilizaram-se seis grupos de quatro bulbos de A. cepa, cada grupo correspondendo a um dos tratamentos. Os bulbos foram enraizados em água destilada e então transferidos para os respectivos tratamentos onde permaneceram por 24 horas (os bulbos do controle negativo permaneceram em água destilada). As radículas foram coletadas, fixadas em etanol-ácido acético (3:1) por 24 horas e armazenadas em álcool 70%. Foram analisadas 4,000 células por grupo de bulbos, e os índices mitóticos calculados submetidos à análise estatística pelo teste c 2. Os extratos aquosos de C. sinensis têm como componentes principais flavonoides e ácidos fenólicos. Os valores dos índices mitóticos diminuíram com o aumento das concentrações dos extratos, em relação ao controle em água. Os resultados indicaram que os extratos aquosos de laranjeira nas concentrações estudadas das duas populações possuem ação antiproliferativa e genotóxica sobre o ciclo celular de A. cepa.

Inhibition of metalloproteinase and proteasome activities in colon cancer cells by citrus peel extracts.

BACKGROUND: Citrus peels are consumed in the form of infusions, candy or wine, based on their well-documented nutritional and medicinal properties. This study sought to investigate the effect of some citrus peels' [grapefruit (Citrus paradisii), orange (Citrus sinensis) and shaddock (Citrus maxima)] extracts on matrix metalloproteinase (MMP) and proteasome activities in primary human colonic tumor (Caco-2) and the metastatic cell lines (LoVo and LoVo/ADR) in a bid to explain the possible mechanism by which the peels could manage/prevent colon cancer. METHODS: The inhibition of MMP and proteasome activities in the cells by the peel extracts, as well as the identification of phenolic compounds using high-performance liquid chromatography with diode-array detection (HPLC-DAD), was determined. RESULTS: Orange peel extracts had the strongest inhibition of MMP in Caco-2 and LoVo cells, while shaddock had the least. Shaddock peel extracts also had the least MMP inhibition in LoVo/ADR lysates. Grapefruit had the least proteasome inhibition in Caco-2 and LoVo lysates, while there was no significant (p>0.05) difference in the proteasome inhibition of the peel extracts in LoVo/ADR lysates. The extracts inhibited proteasome activity in extract-treated cells, and HPLC fingerprinting of the extracts revealed the presence of some phenolic compounds such as quercetin, caffeic acid, kaempferol, catechin and naringin. CONCLUSIONS: The inhibition of MMP and proteasome activities in colon cancer cell lines suggests the potential use of citrus peels as functional food in the management and/or prevention of colon cancer.

Development and Validation of an HPLC-DAD Analysis for Flavonoids in the gel of Scutia buxifolia.

Recent interest in flavonoids has increased greatly due to their biological and pharmacological activities. Flavonoids consist of a large group of low molecular weight polyphenolic substances, naturally occurring in fruits, vegetables and tea, and are an integral part of the human diet. Quercetin and rutin are bioactive markers of Scutia buxifolia and no analytical methods reported so far, associated with quality control of polyherbal formulations containing this species. Therefore, there is a need to develop a sensitive, simple, rapid and reliable method that can simultaneously determine these markers in their combinations. A high-performance liquid chromatography method has been developed and validated as per ICH guidelines. The chromatographic analysis was performed using a C18 column, the mobile phase system consisted of acetonitrile-water (70 : 30, v/v) containing 0.5% (v/v) phosphoric acid and quercetin and rutin were quantificadoa to 356 nm. The proposed method for the quantification of quercetin and rutin in the S. buxifolia fraction (EaSb) and gel was linear, sensitive, precise, specific, accurate and robust. This validated method can be used to control the quality of the EaSb and the gel.

In vitro antimicrobial and modulatory activity of the natural products silymarin and silibinin.

Silymarin is a standardized extract from the dried seeds of the milk thistle (Silybum marianum L. Gaertn.) clinically used as an antihepatotoxic agent. The aim of this study was to investigate the antibacterial and antifungal activity of silymarin and its major constituent (silibinin) against different microbial strains and their modulatory effect on drugs utilized in clinical practice. Silymarin demonstrated antimicrobial activity of little significance against the bacterial strains tested, with MIC (minimum inhibitory concentration) values of 512 µg/mL. Meanwhile, silibinin showed significant activity against Escherichia coli with a MIC of 64 µg/mL. The results for the antifungal activity of silymarin and silibinin demonstrated a MIC of 1024 µg/mL for all strains. Silymarin and silibinin appear to have promising potential, showing synergistic properties when combined with antibacterial drugs, which should prompt further studies along this line.

Centella asiatica and Its Fractions Reduces Lipid Peroxidation Induced by Quinolinic Acid and Sodium Nitroprusside in Rat Brain Regions.

Oxidative stress has been implicated in several pathologies including neurological disorders. Centella asiatica is a popular medicinal plant which has long been used to treat neurological disturbances in Ayurvedic medicine. In the present study, we quantified of compounds by high performance liquid chromatography (HPLC) and examined the phenolic content of infusion, ethyl acetate, n-butanolic and dichloromethane fractions. Furthermore, we analyzed the ability of the extracts from C. asiatica to scavenge the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) radical as well as total antioxidant activity through the reduction of molybdenum (VI) (Mo(6+)) to molybdenum (V) (Mo(5+)). Finally, we examined the antioxidant effect of extracts against oxidant agents, quinolinic acid (QA) and sodium nitroprusside (SNP), on homogenates of different brain regions (cerebral cortex, striatum and hippocampus). The HPLC analysis revealed that flavonoids, triterpene glycoside, tannins, phenolic acids were present in the extracts of C. asiatica and also the phenolic content assay demonstrated that ethyl acetate fraction is rich in these compounds. Besides, the ethyl acetate fraction presented the highest antioxidant effect by decreasing the lipid peroxidation in brain regions induced by QA. On the other hand, when the pro-oxidant agent was SNP, the potency of infusion, ethyl acetate and dichloromethane fractions was equivalent. Ethyl acetate fraction from C. asiatica also protected against thiol oxidation induced by SNP and QA. Thus, the therapeutic potential of C. asiatica in neurological diseases could be associated to its antioxidant activity.

Effect of Scutia buxifolia Reissek in nucleotidase activities and inhibition of platelet aggregation.

This study aimed to determine the effect of lyophilized aqueous extracts of Scutia buxifolia on NTPDase and 5'-nucleotidase activity on platelets and lymphocytes as well as the profile of the platelet aggregation. In vitro tests were used to investigate the effect of the aqueous crude extract obtained from S. buxifolia leaves (SbL) and stem bark (SbS) on enzymatic activities and platelet aggregation. The platelets and lymphocytes were exposed to lyophilized aqueous extracts of S. buxifolia at concentrations of 1-200 µg/mL in the presence of ATP, ADP, AMP as substrates, during the enzymatic assay, as well as the platelet aggregation. The results showed that SbS and SbL potently inhibited NTPDase and 5'-nucleotidase in platelets and lymphocytes. ADP-induced aggregation was inhibited by the SbS (50, 100, and 200 µg/mL) and SbL (200 µg/mL). In addition, these results suggest that S. buxifolia have compounds, such as gallic acid, chlorogenic acid, caffeic acid, quercetin, rutin, and kaempferol, which cause a decrease the NTPDase and 5'-nucleotidase activity, resulting in alterations in adenine nucleotide levels and protection against ADP-induced platelet aggregation.

HPLC-DAD Phenolic Characterization and Antioxidant Activities of Ripe and Unripe Sweet Orange Peels.

Phenolic compounds of unripe and ripe sweet orange peels were determined using a high-performance liquid chromatography separation method with diode array detector (HPLC-DAD). The in vitro antioxidant properties and the EC50 (concentration required to obtain a 50% antioxidant effect) values were also determined. The predominant phenolic compounds were quercitrin, rutin, and quercetin with values of 18.77 ± 0.01 mg/mL, 18.65 ± 0.03 mg/mL, and 10.39 ± 0.01 mg/mL respectively in unripe orange peel and 22.61 ± 0.01 mg/mL, 17.93 ± 0.03 mg/mL, and 14.03 ± 0.02 mg/mL respectively in ripe orange peel. The antioxidant properties revealed 2,2'-azino-bis(3-ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging ability of both unripe and ripe orange peels respectively as 14.68 ± 0.01 and 16.89 ± 0.02 mmol TEAC/g, the Ferric Reducing Antioxidant Properties (FRAP) as 70.69 ± 0.01 and 91.38 ± 0.01 mg gallic acid equivalents/100g, total phenol content as 5.27 ± 0.03 and 9.40 ± 0.01 mg gallic acid equivalents/g and total flavonoid content as 3.30 ± 0.30 and 4.20 ± 0.02 mg quercetin equivalent/g. The antioxidant assays showed enhanced potency of extract from ripe orange peel with EC50 values of 2.71 ± 0.03 mg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 0.67 ± 0.03 mg/mL for hydroxyl radicals (OH*), 0.57 ± 0.02 mg/mL for Fe(2+) chelation, and 0.63 ± 0.06 mg/mL for malondialdehyde (MDA), and was more potent than unripe orange peel.