Optimization of Magnetic and Paper-Based Molecularly Imprinted Polymers for Selective Extraction of Charantin in Momordica charantia.

Charantin is a mixture of ß-sitosterol and stigmastadienol glucosides, which effectively lowers high blood glucose. Novel molecularly imprinted polymers coated magnetic nanoparticles (Fe3O4@MIPs) and filter paper (paper@MIPs) were synthesized by sol-gel polymerization to selectively extract charantin. ß-sitosterol glucoside was selected as a template for imprinting a specific recognition owing to its larger molecular surface area than that of 5,25-stigmastadienol glucoside. Factorial designs were used to examine the effects of the types of porogenic solvents and cross-linkers on the extraction efficiency and imprinting factor before investigating other factors (for example, amounts of template and coated MIPs, and types of substrates for MIP immobilization). Compared to traditional liquid-liquid extraction, the optimal Fe3O4@MIP-based dispersive micro-solid phase extraction and paper@MIP extraction provided excellent extraction efficiency (87.5 ± 2.1% and 85.0 ± 2.9%, respectively) and selectivity. Charantin was well separated, and a new unidentified sterol glucoside was observed using the developed high-performance liquid chromatography with diode-array detection (Rs ≥ 2.0, n > 16,400). The developed methods were successfully utilized to extract and quantify charantin from M. charantia fruit powder and herbal products. Moreover, these methods are rapid (<10 min), inexpensive, simple, reproducible, and environmentally friendly.

Momordica charantia Suppresses Inflammation and Glycolysis in Lipopolysaccharide-Activated RAW264.7 Macrophages.

Macrophage activation is a key event that triggers inflammatory response. The activation is accompanied by metabolic shift such as upregulated glucose metabolism. There are accumulating evidences showing the anti-inflammatory activity of Momordica charantia. However, the effects of M. charantia on inflammatory response and glucose metabolism in activated macrophages have not been fully established. The present study aimed to examine the effect of M. charantia in modulating lipopolysaccharide (LPS)-induced inflammation and perturbed glucose metabolism in RAW264.7 murine macrophages. The results showed that LPS-induced NF-κB (p65) nuclear translocation was inhibited by M. charantia treatment. In addition, M. charantia was found to reduce the expression of inflammatory genes including IL6, TNF-α, IL1ß, COX2, iNOS, and IL10 in LPS-treated macrophages. Furthermore, the data showed that M. charantia reduced the expression of GLUT1 and HK2 genes and lactate production (-28%), resulting in suppression of glycolysis. Notably, its effect on GLUT1 gene expression was found to be independent of LPS-induced inflammation. A further experiment also indicated that the bioactivities of M. charantia may be attributed to its key bioactive compound, charantin. Taken together, the study provided supporting evidences showing the potential of M. charantia for the treatment of inflammatory disorders.

Pharmacokinetic Profile and Oral Bioavailability of Diosgenin, Charantin, and Hydroxychalcone From a Polyherbal Formulation.

Background: Diosgenin, charantin, and hydroxychalcone are utilized for standardization of popular antidiabetic herbal drugs Trigonella foenum-graecum L. belonging to family Fabaceae, Momordica charantia L. belonging to family Cucurbitaceae, and Cinnamomum verum J. Presl belonging to family Lauraceae. However, no reports on the bioavailability of these markers were available. The present study was undertaken to determine the bioavailability and pharmacokinetic profile of the markers and formulations containing the herbs. Methods: The pharmacokinetic profile and absolute bioavailability of the pure active markers were determined in male Wistar rats by administrating individually the doses of 1.5 mg/kg i.v. and 15 mg/kg p.o., followed by estimation of serum levels of the markers at 0, 10, 30, 60, 120, and 240 mins till 24 h time points by a validated bioanalytical HPTLC method. Two standardized antidiabetic capsule formulations containing spray dried hydroalcoholic extracts of seeds of Trigonella foenum-graecum L. (42.8 mg equivalent to 0.95%w/w of diosgenin), fresh fruits of Momordica charantia L. (21.4 mg equivalent to 0.4% w/w of charantin), and bark of Cinnamomum verum J. Presl (10.71 mg equivalent to 0.079 %w/w hydroxychalcone) were prepared. In one formulation, piperine 1.5 mg was added along with the other herbal extracts mentioned. Bioavailability and pharmacokinetic profile of these two formulations were determined in male Wistar rats through estimating serum levels of active markers diosgenin, charantin, and hydroxychalcone at 0, 10, 30, 60, 120, and 240 mins till 24 h later oral administration of the formulations (Formulation without piperine F1 and formulation with Piperine F2). Results: Plasma concentrations were found to decline mono-exponentially following intravenous administration, and the mean elimination half-life (t1/2) was observed to be 7.93, 8.21, and 4.66 h, respectively. The absolute oral bioavailability of pure markers was observed to be 9.0 ± 0.2%, 8.18 ± 0.36%, and 10.54 ± 0.52% by the dose normalization method. The oral bioavailabilities of the formulations with respect to diosgenin, charantin, and hydroxychalcone were found to be 9.78, 10.743, and 8.07%, respectively. The formulation containing piperine indicated a significant (p < 0.01) increase in the bioavailabilities of all the marker compounds. Conclusion: In conclusion, diosgenin and charantin have low bioavailabilities as compared to hydroxychalcone. The bioavailabilities of all the three marker compounds can be increased exponentially with the addition of piperine.

Physicochemical and Functional Characterization of Newly Designed Biopolymeric-Based Encapsulates with Probiotic Culture and Charantin.

The identification of novel sources of synbiotic agents with desirable functionality is an emerging concept. In the present study, novel encapsulates containing probiotic L. acidophilus LA-05® (LA) and Charantin (CT) were produced by freeze-drying technique using pure Whey Protein Isolate (WPI), pure Maltodextrin (MD), and their combination (WPI + MD) in 1:1 core ratio, respectively. The obtained microparticles, namely WPI + LA + CT, MD + LA + CT, and WPI + MD + LA + CT were tested for their physicochemical properties. Among all formulations, combined carriers (WPI + MD) exhibited the highest encapsulation yields for LA (98%) and CT (75%). Microparticles showed a mean d (4, 3) ranging from 50.393 ± 1.26 to 68.412 ± 3.22 µm. The Scanning Electron Microscopy revealed uniformly amorphous and glass-like structures, with a noticeably reduced porosity when materials were combined. In addition, Fourier Transform Infrared spectroscopy highlighted the formation of strong hydrogen bonds supporting the interactions between the carrier materials (WPI and MD) and CT. In addition, the thermal stability of the combined WPI + MD was superior to that of pure WPI and pure MD, as depicted by the Thermogravimetric and Differential Scanning Calorimetry analysis. More interestingly, co-encapsulation with CT enhanced LA viability (8.91 ± 0.3 log CFU/g) and Cells Surface Hydrophobicity (82%) in vitro, in a prebiotic-like manner. Correspondingly, CT content was heightened when co-encapsulated with LA. Besides, WPI + MD + LA + CT microparticles exhibited higher antioxidant activity (79%), α-amylase inhibitory activity (83%), and lipase inhibitory activity (68%) than single carrier ones. Furthermore, LA viable count (7.95 ± 0.1 log CFU/g) and CT content (78%) were the highest in the blended carrier materials after 30 days of storage at 4 °C. Synbiotic microparticle WPI + MD + LA + CT represents an effective and promising approach for the co-delivery of probiotic culture and bioactive compounds in the digestive tract, with enhanced functionality and storage properties.

Bitter Melon (Momordica charantia L.) Fruit Bioactives Charantin and Vicine Potential for Diabetes Prophylaxis and Treatment.

Natural products are gaining clinical significance in modern day health care systems to prevent diseases. Bitter melon, a health promoting vegetable, is traditionally used for medical nutrition therapy to cure diabetes but to reap maximum health claims, vigilant control of its substances in diet is crucial as part of curative action for effective diabetes management. In the present research, first phase focused on detection of key bioactive components, i.e., charantin and vicine in different parts of its fruit. In the second phase, normal and hyperglycemic Sprague Dawley rats were fed on skin, flesh and whole fruit of bitter melon at 150 and 300 mg/kg body weight and assessed for diabetes prophylaxis and treatment. The highest amount of charantin (0.16 ± 0.02 mg/g) was recorded in flesh while vicine was present in abundance in whole fruit (0.21 ± 0.01 µg/100 g). In normal rats, bitter melon supplementation was helpful in managing the onset of diabetes. Hyperglycemic rats showed diabetic complications including polydipsia, polyuria, glycosuria, renal hypertrophy and increased glomerular filtration rate. However, bitter melon consumption showed significant improvements in these parameters. The most potent dose was 300 mg/kg whole fruit that resulted in 31.64% lowering of blood glucose level and 27.35% increase in insulin level in hyperglycemic rats.

Evaluation of Growth, Yield, and Biochemical Attributes of Bitter Gourd (Momordica charantia L.) Cultivars under Karaj Conditions in Iran.

Vegetative and reproductive characteristics, fruit yield, and biochemical compounds of six bitter melon cultivars (Iranshahr, Mestisa, No. 486, Local Japanese, Isfahan, and Ilocano) were evaluated under Karaj conditions in Iran. The phytochemical properties of the cultivars were evaluated using both shade-dried and freeze-dried samples at three fruit developmental stages (unripe, semi-ripe, and ripe). There were significant differences in the vegetative and reproductive characteristics among cultivars, where cv. No. 486 was superior to most vegetative attributes. The fruit yield of cultivars varied from 2.98-5.22 kg/plant. The number of days to male and female flower appearance ranged from 19.00-25.33 and from 25-33 days, respectively. The leaf charantin content was in the range of 4.83-11.08 µg/g. Fruit charantin content varied with developmental stage, drying method, and cultivar. The highest charantin content (13.84 ± 3.55 µg/g) was observed at the semi-ripe fruit stage, and it was much higher in the freeze-dried samples than the shade-dried samples. Cultivar No. 486 had the highest (15.43 ± 2.4 µg/g) charantin content, whereas the lowest charantin content (8.51 ± 1.15 µg/g) was recorded in cultivar cv. Local Japanese. The highest total phenol content (25.17 ± 2.27 mg GAE/g) was recorded in freeze-dried samples of ripe fruits of cv. No. 486, whereas the lowest phenol content was detected in the shade-dried samples of semi-ripe fruits of Isfahan. cv. Flavonoid content was higher with the shade-drying method, irrespective of cultivar. In conclusion, considering the fruit yield and active biological compounds in the studied cultivars, cv. No. 486 should be grown commercially because of its higher yield and production of other secondary metabolites.

Isolation, characterization and quantitative HPLC-DAD analysis of components of charantin from fruits of Momordica charantia.

Charantin, a steroidal glycoside, exists as a mixture of stigmasterol glucoside (STG) and ß-sitosterol glucoside (BSG) in the fruits of Momordica charantia. Charantin has anti-diabetic activity comparable to insulin. The present work discusses a method for separation of components of charantin namely STG and BSG by simple extraction technique followed by preparative HPLC. The identity of separated components was established by chromatographic as well as spectral techniques. Also reversed phase HPLC-DAD method was developed and validated for estimation of STG and BSG present in fruits of Momordica charantia. The method used C18 column (75 mm × 4.6 mm, 3.5 µm) as stationary phase and methanol: water (98:02, v/v) as mobile phase. Retention times of STG and BSG were found to be 10.707 min and 11.870 min, respectively. The validated method was applied to evaluate content of these components in different extracts and some commercial herbal formulations containing fruits of Momordica charantia.

Accumulation of Charantin and Expression of Triterpenoid Biosynthesis Genes in Bitter Melon (Momordica charantia).

Charantin, a natural cucurbitane type triterpenoid, has been reported to have beneficial pharmacological functions such as anticancer, antidiabetic, and antibacterial activities. However, accumulation of charantin in bitter melon has been little studied. Here, we performed a transcriptome analysis to identify genes involved in the triterpenoid biosynthesis pathway in bitter melon seedlings. A total of 88,703 transcripts with an average length of 898 bp were identified in bitter melon seedlings. On the basis of a functional annotation, we identified 15 candidate genes encoding enzymes related to triterpenoid biosynthesis and analyzed their expression in different organs of mature plants. Most genes were highly expressed in flowers and/or fruit from the ripening stages. An HPLC analysis confirmed that the accumulation of charantin was highest in fruits from the ripening stage, followed by male flowers. The accumulation patterns of charantin coincide with the expression pattern of McSE and McCAS1, indicating that these genes play important roles in charantin biosynthesis in bitter melon. We also investigated optimum light conditions for enhancing charantin biosynthesis in bitter melon and found that red light was the most effective wavelength.

Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology.

BACKGROUND: Momordica charantia Linn. (Cucurbitaceae) fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. OBJECTIVE: The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. MATERIALS AND METHODS: Response surface methodology (RSM) was used for the optimization of ultrasound-assisted extraction (UAE) conditions. RSM was based on a three-level, three-variable Box-Behnken design (BBD), and the studied variables included solid to solvent ratio, extraction temperature, and extraction time. RESULTS: The optimal conditions predicted by the BBD were: UAE with methanol: Water (80:20, v/v) at 46°C for 120 min with solid to solvent ratio of 1:26 w/v, under which the yield of charantin was 3.18 mg/g. Confirmation trials under slightly adjusted conditions yielded 3.12 ± 0.14 mg/g of charantin on dry weight basis of fruits. The result of UAE was also compared with Soxhlet extraction method and UAE was found 2.74-fold more efficient than the Soxhlet extraction for extracting charantin. CONCLUSIONS: A facile UAE protocol for a high extraction yield of charantin was developed and validated.

Differential anti-diabetic effects and mechanism of action of charantin-rich extract of Taiwanese Momordica charantia between type 1 and type 2 diabetic mice.

Momordica charantia Linn. (Cucurbitaceae), also called bitter melon, has traditionally been used as a natural anti-diabetic agent for anti-hyperglycemic activity in several animal models and clinical trials. We investigated the differences in the anti-diabetic properties and mechanism of action of Taiwanese M. charantia (MC) between type 1 diabetic (T1D) and type 2 diabetic (T2D) mice. To clarify the beneficial effects of MC, we measured non-fasting glucose, oral glucose tolerance, and plasma insulin levels in KK/HIJ mice with high-fat diet-induced diabetes (200 mg/kg/day of charantin-rich extract of MC [CEMC]) and in ICR mice with STZ-induced diabetes. After 8 weeks, all the mice were exsanguinated, and the expression of the insulin-signaling-associated proteins in their tissue was evaluated, in coordination with the protective effects of CEMC against pancreatic ß-cell toxicity (in vitro). Eight weeks of data indicated that CEMC caused a significant decline in non-fasting blood glucose, plasma glucose intolerance, and insulin resistance in the KK/HIJ mice, but not in the ICR mice. Furthermore, CEMC decreased plasma insulin and promoted the sensitivity of insulin by increasing the expression of GLUT4 in the skeletal muscle and of IRS-1 in the liver of KK/HIJ mice; however, CEMC extract had no effect on the insulin sensitivity of ICR mice. In vitro study showed that CEMC prevented pancreatic ß cells from high-glucose-induced cytotoxicity after 24 h of incubation, but the protective effect was not detectable after 72 h. Collectively, the hypoglycemic effects of CEMC suggest that it has potential for increasing insulin sensitivity in patients with T2D rather than for protecting patients with T1D against ß-cell dysfunction.