Ultrasonic-Assisted Extraction of Xanthorrhizol from Curcuma xanthorrhiza Roxb. Rhizomes by Natural Deep Eutectic Solvents: Optimization, Antioxidant Activity, and Toxicity Profiles.

Xanthorrhizol, an important marker of Curcuma xanthorrhiza, has been recognized for its different pharmacological activities. A green strategy for selective xanthorrhizol extraction is required. Herein, natural deep eutectic solvents (NADESs) based on glucose and organic acids (lactic acid, malic acid, and citric acid) were screened for the extraction of xanthorrhizol from Curcuma xanthorrhiza. Ultrasound-assisted extraction using glucose/lactic acid (1:3) (GluLA) gave the best yield of xanthorrhizol. The response surface methodology with a Box-Behnken Design was used to optimize the interacting variables of water content, solid-to-liquid (S/L) ratio, and extraction to optimize the extraction. The optimum conditions of 30% water content in GluLA, 1/15 g/mL (S/L), and a 20 min extraction time yielded selective xanthorrhizol extraction (17.62 mg/g) over curcuminoids (6.64 mg/g). This study indicates the protective effect of GluLA and GluLA extracts against oxidation-induced DNA damage, which was comparable with those obtained for ethanol extract. In addition, the stability of the xanthorrhizol extract over 90 days was revealed when stored at -20 and 4 °C. The FTIR and NMR spectra confirmed the hydrogen bond formation in GluLA. Our study reported, for the first time, the feasibility of using glucose/lactic acid (1:3, 30% water v/v) for the sustainable extraction of xanthorrhizol.

The neuroprotective potential of turmeric rhizome and bitter melon on aspartame-induced spatial memory impairment in rats.

Aspartame is widely used artificial sweetener. However, chronic exposure to aspartame led to spatial memory impairment and elevated oxidative stress in the brain. Extract of turmeric rhizome (Curcuma longa) (TUR) and extract of bitter melon (Momordica charantia) (BM) is known to have antioxidant activity. The present study was aimed to examine the neuroprotective potential of TUR and BM extracts, either as single or as combination, against the effects of aspartame in the brain. Here, Sprague-Dawley rats fed with aspartame (40 mg/kg BW) for 28 days were compared with rats fed with extract and aspartame. To assess neuroprotective potential, rats were given extract 7 days before and during aspartame treatment. Spatial memory was assessed with Morris water maze test followed with H&E staining of hippocampal region. Brain lipid peroxidation and enzymatic activity of malondialdehyde (MDA), glutathione peroxidase (GPx), and Acetylcholinesterase (AChE) were measured to probe status of oxidative stress in the brain. Aspartame-treated rats demonstrated spatial memory impairment and reduced number of hippocampal cells and elevated levels of MDA, downregulated activity of GPx and elevated activity of AChE. In contrast, animals received both aspartame and extract demonstrated better spatial memory function, higher number of hippocampal areas, increased GPX activity, reduced MDA levels, and decreased AChE activity were observed in the brain of extract-treated rats. Taken together, our results suggest that extract of TUR rhizome and BM fruit exhibit antioxidant activity which may contribute to the neuroprotective effects against aspartame-induced memory impairment in rats.

Natural Deep Eutectic Solvent based Ultrasound-assisted extraction: A green approach for extraction of sulfhydryl and mimosine from Leucaena leucocephala (Lam) de Wit seeds.

Leucaena leucocephala (Lam.) de Wit seeds, also known as river tamarind, contain sulfhydryl compounds that exhibit antioxidant effects. However, these seeds also possess a toxic effect from mimosine. In this study, the river tamarind seeds were extracted using a natural deep eutectic solvent (NADES) based UAE. Among six NADES compositions screened, choline chloride-glycerol (ChCl-Gly) and choline chloride-sucrose (ChCl-Suc) were selected to be further optimized using a Box-Behnken Design in the RSM. The optimization of total sulfhydryl content was performed in 17 runs using three variables, namely water content in NADES (39%, 41%, and 43%), extraction time (5, 10, and 15 min), and the liquid-solid ratio (3, 5, and 7 mL/g). The highest concentration of sulfhydryls was obtained from ChCl-Gly-UAE (0.89 mg/g sample) under the conditions of a water content in NADES of 41% (v/v) and a liquid-solid ratio of 3 mL/g for 15 min, followed by that of from ChCl-Suc-UAE extract under the conditions of water content in NADES of 43% (v/v) and the liquid-solid ratio of 3 mL/g for 10 min with total sulfhydryl level was 0.67 mg/g sample. The maceration method using 30% ethanol resulted in the lowest level of sulfhydryls with a value of 0.52 mg/g. The mimosine compounds obtained in the NADES-based UAE (ChCl-Suc and ChCl-Gly) extracts were 4.95 and 7.67 mg/g, respectively, while 12.56 mg/g in the 30% ethanol-maceration extract. The surface morphology of L. leucocephala seed before and after extraction was analyzed using scanning electron microscopy. Therefore, it can be concluded that the use of ChCl-Suc and ChCl-Gly in NADES-based UAE is more selective in attracting sulfhydryl compounds than that of 30% ethanol-maceration extraction.

Detoxification of comfrey (Symphytum officinale L.) extract using natural deep eutectic solvent (NADES) and evaluation of its anti-inflammatory, antioxidant, and hepatoprotective properties.

Comfrey (Symphytum officinale L.) contains rosmarinic acid which has different pharmacological activities, such as antioxidant and anti-inflammatory activities. However, the medicinal use of comfrey is limited by the hepatotoxic effect of lycopsamine in comfrey, which overshadows the health benefits of rosmarinic acid. Natural deep eutectic solvents (NADES) have a wide range of extraction properties, that provides a new approach to the detoxification of comfrey. In the present study, betaine-based and choline chloride-based NADES were screened for selective extraction of rosmarinic acid over lycopsamine. Ultrasonication was used in conjunction with NADES extraction. The chemical profile of the NADES extracts on antioxidant, anti-inflammatory and hepatotoxic activities were investigated using some chemical reagents. Betaine-urea (1:2 molar ratio, 50% water) obtained the highest content of rosmarinic acid and a low level of lycopsamine (1.934 and 0.018 mg/g, respectively). Betaine-urea was also shown to be more effective to extract rosmarinic acid compared to methanol-UAE under the same conditions, which gave lower rosmarinic acid and higher lycopsamine levels (0.007 and 0.031 mg/g, respectively). Betaine-urea extracts showed higher antioxidant and anti-inflammatory properties as compared with other NADES extracts, however, had lower hepatotoxic profile. This study recommends the use of betaine-urea to detroxify comfrey to open wider opportunities for the development of comfrey for medicinal use.

Angiotensin converting enzyme (ACE) inhibitors activity from purified compounds Fructus Phaleria macrocarpa (Scheff) Boerl.

BACKGROUND: Mahkota Dewa [Phaleria macrocarpa (Scheff) Boerl.] fruit in vitro and in- vivo can decrease and prevent elevation of the blood pressure, lower plasma glucose levels, possess an antioxidant effect, and recover liver and kidney damage in rats. This study aimed to determine the structure and inhibitory activity of angiotensin-converting enzyme inhibitors (ACE) from the Mahkota Dewa fruit. METHODS: The fruit powder was macerated using methanol and then partitioned by hexane, ethyl acetate, n-butanol, and water. The fractions were chromatographed on the column chromatography and incorporated with TLC and recrystallization to give pure compounds. The structures of isolated compounds were determined by UV-Visible, FT-IR, MS, proton (1H-NMR), carbon (13C-NMR), and 2D-NMR techniques encompassing HMQC and HMBC spectra. The compounds were evaluated for their ACE inhibitory activity, and the strongest compound was determined by the kinetics enzyme inhibition. RESULTS: Based on the spectral data, the isolated compounds were determined as 6,4-dihydroxy-4-methoxybenzophenone-2-O-ß-D-glucopyranoside (1), 4,4'-dihydroxy-6-methoxybenzophenone-2-O-ß-D-glucopyranoside (2) and mangiferin (3). IC50 values of the isolated compounds 1, 2 and 3 were 0.055, 0.07, and 0.025 mM, respectively. CONCLUSION: The three compounds have ACE inhibitor and mangiferin demonstrated the best ACE inhibitory activity with competitive inhibition on ACE with the type of inhibition kinetics is competitive inhibition.

Xanthorrhizol, a potential anticancer agent, from Curcuma xanthorrhiza Roxb.

BACKGROUND: Xanthorrhizol (XTZ), a bisabolene sesquiterpenoid, is abundantly found in the plant Curcuma xanthorrhiza Roxb. Traditionally, C. xanthorrhiza is widely used for the treatment of different health conditions, including common fever, infection, lack of appetite, fatigue, liver complaints, and gastrointestinal disorders. XTZ exhibits wide-ranging pharmacological activities, including anticancer, antioxidative, anti-inflammatory, antimicrobial, and antidiabetic activities, in addition to a protective effect on multiple organs. The present review provides detailed findings on the anticancer activities of XTZ and the underlying cellular and molecular mechanisms. METHODS: Literature was searched systematically in main databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, with keywords "tumor AND xanthorrhizol" or "cancer AND xanthorrhizol". RESULTS: Studies show that XTZ has preventive and therapeutic activities against different types of cancer, including breast, cervical, colon, liver, lung, oral and esophageal, and skin cancers. XTZ regulates multiple signaling pathways that block carcinogenesis and proliferation. In vitro and in vivo studies showed that XTZ targets different kinases, inflammatory cytokines, apoptosis proteins, and transcription factors, leading to the suppression of angiogenesis, metastasis, and the activation of apoptosis and cell cycle arrest. CONCLUSION: The potential anticancer benefits of XTZ recommend further in vivo studies against different types of cancer. Further, XTZ needs to be confirmed for its toxicity, bioavailability, protective, antifatigue, and energy booster activities. Future studies for the therapeutic development of XTZ may be directed to cancer-related fatigue.

Mitragyna Species as Pharmacological Agents: From Abuse to Promising Pharmaceutical Products.

Mitragyna is a genus belonging to the Rubiaceae family and is a plant endemic to Asia and Africa. Traditionally, the plants of this genus were used by local people to treat some diseases from generation to generation. Mitragyna speciosa (Korth.) Havil. is a controversial plant from this genus, known under the trading name "kratom", and contains more than 40 different types of alkaloids. Mitragynine and 7-hydroxymitragynine have agonist morphine-like effects on opioid receptors. Globally, Mitragyna plants have high economic value. However, regulations regarding the circulation and use of these commodities vary in several countries around the world. This review article aims to comprehensively examine Mitragyna plants (mainly M. speciosa) as potential pharmacological agents by looking at various aspects of the plants. A literature search was performed and information collected using electronic databases including Scopus, ScienceDirect, PubMed, directory open access journal (DOAJ), and Google Scholar in early 2020 to mid-2021. This narrative review highlights some aspects of this genus, including historical background and botanical origins, habitat, cultivation, its use in traditional medicine, phytochemistry, pharmacology and toxicity, abuse and addiction, legal issues, and the potential of Mitragyna species as pharmaceutical products.

Peperomia pellucida (L.) Kunth as an angiotensin-converting enzyme inhibitor in two-kidney, one-clip Goldblatt hypertensive rats.

BACKGROUD: Peperomia pellucida (L.) Kunth has been used widely to treat headache, kidney disease, fever, and hypertension. Previous in vitro studies discovered that the flavonoid-rich extract of this plant has potential hypotensive effects, specifically angiotensin-converting enzyme (ACE)-inhibitory activity. However, there is insufficient scientific evidence to validate the result in vivo. PURPOSE: This study investigated the dose dependencies of the effects of the ethyl acetate fraction of the ethanolic extract of this plant on blood pressure and biomarkers associated with the renin-angiotensin-aldosterone systems (RAAS), such as angiotensin II (AII) and the plasma renin concentration (PRC). STUDY DESIGN: In total, 30 two-kidney, one-clip (2K1C) hypertensive model rats were divided into five groups (n = 6 each): model group, captopril 25 mg/kg BW group, and three different ethyl acetate groups (25, 50, and 100 mg/kg BW). Another six rats comprised the sham group. METHODS: Renal hypertensive rats (RHRs) were generated using stainless steel modification clips. Drugs were administered via oral gavage for 2 consecutive weeks. Blood pressure was measured weekly prior to treatment. Blood samples were collected before treatment and after the last dose to measure AII and PRC. The left kidney was isolated for histopathological examination. RESULTS: Blood pressure, AII levels, and PRC were elevated after 6 weeks in RHRs. Treatment with captopril and the ethyl acetate fraction of P. pellucida (L.) Kunth decreased blood pressure, AII levels, and PRC. The ethyl acetate fraction at a dose of 50 mg/kg BW had similar ACE-inhibitory effects as captopril. Histopathological examination disclosed coagulative necrosis in clipped kidneys. Impairment was alleviated in a dose-dependent manner by P. pellucida (L.) Kunth, similarly as observed in the captopril group. CONCLUSION: P. pellucida (L.) Kunth targets the renin-angiotensin-aldosterone system, which might explain its antihypertensive effects.

Natural Deep Eutectic Solvents (NADES): Phytochemical Extraction Performance Enhancer for Pharmaceutical and Nutraceutical Product Development.

Natural products from plants were extracted and widely studied for their activities against many disease conditions. The selection of the extracting solvent is crucial to develop selective and effective methods for the extraction and isolation of target compounds in the plant matrices. Pharmacological properties of plant extracts and their bioactive principles are related to their excellent solubility, stability, and bioavailability when administered by different routes. This review aims to critically analyze natural deep eutectic solvents (NADES) as green solvents in their application to improve the extraction performance of plant metabolites in terms of their extractability besides the stability, bioactivity, solubility, and bioavailability. Herein, the opportunities for NADES to be used in pharmaceutical formulations development including plant metabolites-based nutraceuticals are discussed.

Effect of gamma irradiation on the caffeoylquinic acid derivatives content, antioxidant activity, and microbial contamination of Pluchea indica leaves.

Pluchea indica (L.) Less. leaf has a long history of being used as a food and in traditional medicines. Although gamma irradiation is an effective decontamination method, it must be performed appropriately to preserve the bioactive constituents and biological activities of the plant. This study investigated the influence of gamma irradiation on the caffeoylquinic acid derivatives content, antioxidant capacity, and microbial burden of P. indica leaf. Dried P. indica leaf powder was exposed to gamma rays from cobalt-60 at the absorbed doses of 2.5, 5.0, 7.5, and 10 kGy. After a maceration of P. indica leaf with 70% ethanol, the content of six caffeoylquinic acid derivatives (CQAs) in the extract was assayed using high-performance liquid chromatography. The antioxidant capacity of the ethanolic extract was also determined using the DPPH, ABTS, and ferric reducing antioxidant power (FRAP) methods. The total aerobic bacteria and total yeast and mold counts were investigated using the Petrifilm method at 0 and 3 months after irradiation. Doses of 5-10 kGy significantly increased the CQA level (P < 0.05). The antioxidant activity was enhanced significantly at 2.5-10 kGy (P < 0.05). Doses of 2.5-10 kGy also effectively reduced the microbial load (P < 0.05). Among the irradiation doses, 10 kGy showed the best results. Thus, gamma irradiation at 10 kGy is useful in increasing CQA content and antioxidant capacity as well as reducing the microbial load of P. indica leaf.

Optimization of betaine-sorbitol natural deep eutectic solvent-based ultrasound-assisted extraction and pancreatic lipase inhibitory activity of chlorogenic acid and caffeine content from robusta green coffee beans.

Natural deep eutectic solvent (NADES) is an alternative approach in natural product extraction with various advantages, including low toxicity, biodegradable, and suitable phytochemical compounds in a wide range of polarity. Chlorogenic acid (CGA) and caffeine, a well-known compound in the coffee bean, have various potential health benefits. This study aims to optimize the betaine-sorbitol NADES-based ultrasound-assisted extraction (UAE) method of CGA and caffeine from Robusta green coffee beans and determine the inhibitory activity of robusta green coffee beans extract of the betaine-sorbitol NADES-UAE from the optimum condition on pancreatic lipase in vitro and in silico. The betaine-sorbitol NADES-UAE factors as experimental design variable parameters include betaine-sorbitol ratio (0.5:1.2, 1.25:1.2, and 2:1.2 mol), extraction time (10, 35, and 60 min), and solid-liquid ratio (1:10, 1:20, and 1:30 g/mL). Response surface methodology and Box-Behnken Design were used to optimize the extraction process. The response surface was calculated by using CGA and caffeine content as response values. CGA and caffeine content was determined by High-Performance Liquid Chromatography. Whereas in vitro lipase inhibitory activity assay examined by spectrophotometric measurement and in silico molecular docking analysis on PDB ID: 1LPB. According to the results, the optimum conditions of the betaine-sorbitol NADES-UAE have obtained the betaine-sorbitol ratio of 1.25: 1.2 mol, solid-liquid ratio of 1:30 mg/mL, and 60 min extraction time. Furthermore, obtained Robusta green coffee extract from the optimum condition of the betaine-sorbitol NADES-UAE showed high potential to inhibit lipase activity with IC50 of 18.02 µg/ml, comparable with IC50 of standard CGA (11.90 µg/ml) and caffeine (15.59 µg/ml), where potential interaction of both standards was confirmed using molecular docking analysis. Our finding demonstrated the optimum condition of the betaine-sorbitol NADES-UAE method for CGA and caffeine extraction and the potential pancreatic lipase inhibition activity from the Robusta green coffee bean.

A green extraction design for enhancing flavonoid compounds from Ixora javanica flowers using a deep eutectic solvent.

In this study, an environmentally friendly extraction method for flavonoid compound from Ixora javanica, as a new raw material candidate for herbal medicine and cosmetics, was developed. The objectives of the present work were to provide recommendations for the optimal extraction conditions and to investigate the effects of any extraction parameters on flavonoid yields from the I. javanica flower. The extraction process was performed using deep eutectic solvent (DES) (choline chloride and propylene glycol at molar ratio of 1 : 1) and the ultrasound-assisted extraction method. Both single-factor and response surface analyses using three-level and three-factor Box Behnken designs were conducted to obtain the optimum flavonoid concentrations. The results showed that the optimum extraction conditions for total flavonoids featured an extraction time of 40 min, 25% water content in DES and a solid-to-liquid ratio of 1 : 25 g ml-1. An extract obtained under optimum extraction conditions showed higher total flavonoid yields than an ethanolic extract which was used for comparison. Scanning electron microscope images demonstrated that both of the solvents also showed different effects on the outer surface of the I. javanica flower during the extraction process. In summary, our work succeeded in determining the optimum conditions for total flavonoids in the I. javanica flower using a green extraction method.

Simultaneous Natural Deep Eutectic Solvent-Based Ultrasonic-Assisted Extraction of Bioactive Compounds of Cinnamon Bark and Sappan Wood as a Dipeptidyl Peptidase IV Inhibitor.

Cinnamon bark (Cinnamomum burmannii) and sappan wood (Caesalpinia sappan) have been reported to be beneficial for Type-2 Diabetes Mellitus (T2DM) and the combination is commonly used by Indonesian herbal industries. In the present study, the simultaneous extraction of bioactive compounds from both plants was conducted using natural deep eutectic solvent (NADES), their content analyzed using high-performance liquid chromatography (HPLC), and their dipeptidyl peptidase IV (DPP IV) inhibitory activity evaluated. An additional in silico molecular docking analysis was conducted to ensure their activity. The results showed that NADES (with a composition of choline chloride-glycerol) extraction from cinnamon and sappan wood had DPP IV inhibitory activity of 205.0 and 1254.0 µg/mL, respectively. Brazilin as a marker substance from sappan wood was responsible for the DPP IV inhibitory activity, while none of the marker substances chosen for cinnamon bark (trans-cinnamaldehyde, coumarin, and trans-cinnamic acid) were found to have significant DPP IV inhibitory activity. These results were confirmed by molecular docking conducted in brazilin, trans-cinnamaldehyde, coumarin, and trans-cinnamic acid.

Application and optimization of ultrasound-assisted deep eutectic solvent for the extraction of new skin-lightening cosmetic materials from Ixora javanica flower.

The high demand for cosmetics has had a great impact on the development of innovative products in the cosmetic industry. The availability of raw materials has become a common problem in the cosmetic industry. Materials from nature can act as alternative sources, such as Ixora javanica. Several studies have shown the potential of I. javanica as an antioxidant and skin lightening agent. The objectives of the present study were to develop and optimize a green ultrasound-assisted deep eutectic solvent extraction of I. javanica. Eleven deep eutectic solvents were evaluated based on extraction efficiency parameters; that is, flavonoid and anthocyanin yields; the antioxidant and tyrosinase inhibitory activities of the extracts. The combination of choline chloride and propylene glycol (1:1) was shown to be the optimal deep eutectic solvent for I. javanica extraction. The extraction parameters of temperature, extraction time, and solid-to-liquid ratio were also optimized using response surface methodology. The total flavonoid compound obtained was 33 mg quercetin equivalent/g dried sample under the optimum extraction condition (extraction time of 5 min, temperature of 57 °C, solid-to-liquid ratio of 0.02 g/mL). In sum, this work demonstrates the potential of natural deep eutectic solvent as an organic solvent replacement to obtain high quality Ixora javanica extract, which is a potential new source of skin-lightening cosmetic materials.

Optimization of choline chloride-glycerol based natural deep eutectic solvent for extraction bioactive substances from Cinnamomum burmannii barks and Caesalpinia sappan heartwoods.

Indonesian cassia (Cinnamomum burmannii Blume) is commonly used as a condiment. It reportedly contains a number of major phytochemical constituents such as trans-cinnamaldehyde and coumarin. Sappan wood (Caesalpinia sappan) is a native plant of Southeast Asia that contains brazilin, a widely known red pigment. This study aimed to determine the optimal extraction conditions using a choline chloride-glycerol (ChCl-glycerol)-based natural deep eutectic solvent (NADES) to obtain greater trans-cinnamaldehyde and brazilin levels from Indonesian cassia and sappan wood. The powders of Indonesian cassia and sappan wood were extracted using ChCl-glycerol-based NADES varied at three different levels: ratio of ChCl to glycerol, ratio of powder to NADES, and the amount of water in NADES. All variables were designed using the Box-Behnken design of response surface methodology to provide 15 extraction conditions. The extraction was performed using ultrasonication-assisted extraction for 30 and 50 min for Indonesian cassia and sappan wood, respectively. Determination of the active compound contents was performed using a high-performance liquid chromatography system equipped with a UV-VIS detector at λmax = 280 nm. The optimization results revealed that the highest levels of trans-cinnamaldehyde, coumarin, and brazilin in NADES extracts were 1907.32, 1735.68, and 368.67 µg/ml, respectively, whereas the lowest levels of these compounds were 453.59, 616.76, and 74.21 µg/ml, respectively. The maximal levels exceeded those obtained using a conventional extraction method, in which 5000 µg/ml Indonesian cassia reflux extract contained only 108.45 µg/ml trans-cinnamaldehyde. Similarly, 1000 µg/ml sappan wood contained only 124.64 µg/ml brazilin. ChCl-glycerol-based NADES was suitable for extracting active compounds from Indonesian cassia and sappan wood; moreover, this solvent is more effective than organic ethanolic coventional solvent.

In silico and in vitro identification of candidate SIRT1 activators from Indonesian medicinal plants compounds database.

Sirtuin 1 (SIRT1) is a class III family of protein histone deacetylases involved in NAD+-dependent deacetylation reactions. It has been suggested that SIRT1 activators may have a protective role against type 2 diabetes, the aging process, and inflammation. This study aimed to explore and identify medicinal plant compounds from Indonesian Herbal Database (HerbalDB) that might potentially become a candidate for SIRT1 activators through a combination of in silico and in vitro methods. Two pharmacophore models were developed using co-crystalized ligands that allosterically bind with SIRT1 similar to the putative ligands used by SIRT1 activators. Then, these were used for the virtual screening of HerbalDB. The identified compounds were subjected to molecular docking and 50 ns molecular dynamics simulation. Molecular dynamics simulation was analyzed using MM-GB(PB)SA methods. The compounds identified by these methods were tested in an in vitro study using a SIRT-Glo™ luminescence assay. Virtual screening using structure-based pharmacophores predicted that mulberrin as the best candidate SIRT1 activator. Virtual screening using ligand-based pharmacophores predicted that gartanin, quinidine, and quinine to be the best candidates as SIRT1 activators. The molecular docking studies showed the important residues involved were Ile223 and Ile227 at the allosteric region. The MM-GB(PB)SA calculations confirmed that mulberrin, gartanin, quinidine, quinine showed activity at allosteric region and their EC50 in vitro values are 2.10; 1.79; 1.71; 1.14 µM, respectively. Based on in silico and in vitro study results, mulberin, gartanin, quinidine, and quinine had good activity as SIRT1 activators.

A new angiotensin-converting enzyme inhibitor from Peperomia pellucida (L.) Kunth

Objective: To isolate, identify, and evaluate a new angiotensin-converting enzyme inhibitor from Peperomia pellucida (L.) Kunth herbs. Methods: A dried sample of Peperomia pellucida herb was successively macerated with n-hexane and ethyl acetate. The ethyl acetate extract solution was evaporated to obtain the crude extract. Vacuum liquid column chromatography and thin layer chromatography were performed to obtain two pure compounds. Then, both compounds were elucidated and identified using the spectroscopic method. Angiotensin-converting enzyme inhibitory activity studies of both compounds were determined using angiotensin-converting enzyme kit WST-1 with spectrophotometer microplate reader 96-well at 450 nm wavelength. Results: Two bioactive compounds were successfully isolated from Peperomia pellucida herb, including a new compound of 2,3,5-trimethoxy-9-(12,14,15-trimethoxybenzyl)-1H-indene and pellucidin A. Both compounds demonstrated angiotensin-converting enzyme inhibitory activity, with IC50 values of 72 μM (27.95 μg/mL) and 11 μM (4.4 μg/mL), respectively. Conclusions: In the present study, two active angiotensin-converting enzyme inhibitors were successfully isolated and purified from Peperomia pellucida which is used as an antihypertensive in traditional medicine, and support its use as an angiotensin-converting enzyme-inhibiting drug.

Potential Gastroprotective Activity of Rice Bran (Oryza sativa L.) Extracted by Ionic Liquid-Microwave-Assisted Extraction against Ethanol-Induced Acute Gastric Ulcers in Rat Model.

The presence of gamma-oryzanol in rice bran oil can be 10⁻20-fold higher than tocopherol and tocotrienol. Gamma-oryzanol has various pharmacological properties. The objective of this study was to evaluate the effectiveness of rice bran extract as a gastroprotective in reducing lesions in ethanol-induced acute gastric ulcer models in rat, using the ionic liquid-microwave-assisted extraction (IL-MAE) method. Rice bran extract was obtained using the IL-MAE method with ionic liquid (IL), 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF4 (concentration 0.7 M), and a ratio of solid/liquid of 15 g/mL, 15 min extraction time, and 10% microwave power. The rats were pretreated with rice bran extract at different doses (100, 200, and 400 mg/kg body weight; BW) for seven days and subsequently exposed to acute gastric lesions induced by 80% ethanol. Omeprazole (36 mg/kg BW) was used as a standard anti-ulcer drug. The ulcer index, gastric juice acidity, and mucus levels were measured to assess the degree of gastroprotection. The results showed that the oral administration of rice bran extract at a dose of 400 mg/kg BW significantly inhibited the development of ulcer formation by 66.75% and reduced gastric acid levels. Moreover, gamma oryzanol and omeprazole protected the gastric mucosa from ethanol-induced gastric lesions by increasing the level of gastric mucus. Rice bran extract is effective as a gastroprotective therapy sourced from natural ingredients in treating the incidence of gastric ulcers. Most likely, this is related to gamma oryzanol as a bioactive compound contained in rice bran (Oryza sativa L.).

Effect of Apium graveolens Extract Administration on the Pharmacokinetics of Captopril in the Plasma of Rats.

Apium graveolens (celery) is an edible and traditionally medicinal plant that is used worldwide, among others for the treatment of hypertension. Combining celery with antihypertensive drugs can affect the pharmacodynamics and pharmacokinetics of the latter drugs. The aim of the study is to assess the effects of administrating the celery extract on captopril pharmacokinetics. Sprague-Dawley strain rats were divided into two groups (n = 6). Group I was given captopril (10 mg/kg Body Weight (BW)) orally, while Group II was pretreated with celery extract orally (40 mg/kg BW) an hour before administration of captopril. The blood samples were withdrawn at various intervals after drug administration. The captopril concentration was determined using liquid chromatography-mass spectrometry (LC-MS/MS) and from the blood data, the values of Ke, Cmax, Tmax, T1/2, and area under the curve (AUC) were calculated. The results showed that oral administration of the celery extract increased Cmax (38.67%), T1/2 (37.84%), and AUC (58.10%) and decreased Ke (27.45%) of captopril in Group II (celery + captopril) compared with Group I (captopril). In conclusion, celery extract can alter the pharmacokinetic of captopril when given in combination. The combination might be beneficial for the treatment of hypertension, as celery causes an increase in the plasma level of captopril, which can enhance its efficacy.

Review of Angiotensin-converting Enzyme Inhibitory Assay: Rapid Method in Drug Discovery of Herbal Plants.

The renin-angiotensin-aldosterone system is a signaling pathway which responsible in the blood pressure regulation. Angiotensin-converting enzyme (ACE) is one of the key elements responsible for the hypertensive mechanism. It converts angiotensin-I to angiotensin-II. The discovery history of the ACE inhibitory activity assay method has been through a long stage for decades and development continues until today. The ACE inhibitory activity has become an effective screening method in the search for new antihypertensive agents from herbal plants. Some of in vitro assay methods were used to examine the activity of ACE inhibitors based on the substrate usage, such as; Cushman and Cheung Method using a substrate hippuryl-histidyl-leucine (HHL), Holmquist method using a substrate furanacryloyl-tripeptide, Elbl and Wagner method using a substrate benzoil-[l-14C] glicyl-L-histidine-L-leucine, Carmel and Yaron method using a substrate o-aminobenzoylglycyl-p-nitrophenylalanilproline, and Lam method using 3-hydroxybutyrylglycyl-glycyl-glycine as substrate. Several different methods to measure the results of enzymatic reactions or separating substrate with products, including spectrophotometric, fluorometric, high-performance liquid chromatography, electrophoresis, and radiochemistry. Application of the test method for screening the ACE inhibitors activity and investigation of active compounds from natural products can be done easily with this method, it is very helpful in research because the results obtained are simple, accurate, and rapid.