Turmeric (Curcuma longa) whole powder reduces accumulation of visceral fat mass and increases hepatic oxidative stress in rats fed a high-fat diet

Effects of turmeric (Curcuma longa) and its constituent (curcumin) on the metabolic syndrome: An updated review

Metabolic syndrome (MS) involves people with the following risk factors: obesity, hypertension, high glucose level and hyperlipidemia. It can increase the risk of heart disease, stroke and type 2 diabetes mellitus. The prevalence of MS in the world's adult population is about 20%-25%. Today, there is much care to use medicinal plants. Turmeric (Curcuma longa) as well as curcumin which is derived from the rhizome of the plant, has been shown beneficial effects on different components of MS. Thus, the purpose of this manuscript was to introduce different in vitro, in vivo and human studies regarding the effect of turmeric and its constituent on MS. Moreover, different mechanisms of action by which this plant overcomes MS have been introduced. Based on studies, turmeric and its bioactive component, curcumin, due to their anti-inflammatory and antioxidant properties, have antidiabetic effects through increasing insulin release, antihyperlipidemic effects by increasing fatty acid uptake, anti-obesity effects by decreasing lipogenesis, and antihypertensive effects by increasing nitric oxide. According to several in vivo, in vitro and human studies, it can be concluded that turmeric or curcumin has important values as a complementary therapy in MS. However, more clinical trials should be done to confirm these effects.

Determination of Curcuma longa L. (Turmeric) Leaf Extraction Conditions Using Response Surface Methodology to Optimize Extraction Yield and Antioxidant Content

Curcuma longa L. (turmeric) has been used as a functional food material, but other parts of it such as leaves are wasted as a byproduct. This work concentrated on developing turmeric leaves as a functional food material by establishing its optimal extraction condition. Response surface methodology was applied to optimize turmeric leaf extraction conditions. Turmeric leaves were pulled out with water and ethanol (10, 30, and 50%). Then, total phenolic compound content, total flavonoid content, and radical-scavenging activity of each extract were quantified to confirm the optimal extracting solvent. According to the results, water was the most efficient solvent to extract antioxidant contents such as total phenolic compounds (3.65 ± 0.02 mg GAE/g) and flavonoids (4.99 ± 0.17 mg QCE/g) content. Radical-scavenging activity was also higher in water extract compared with others such as DPPH (51.10 ± 2.29%), H2O2 (25.39 ± 2.69%), and ABTS (91.08 ± 0.15%). Central composite design was applied to confirm the effect of independent variables such as temperature (X1) and time (X2) to the yield (Y1). After conducting experiments, the extraction condition was established as 150 min with 1 : 25 ratio at 85°C with a 15.58% yield. Proximate compositions of the extract were determined to suggest background data for further research. In conclusion, this study confirmed the antioxidant property of turmeric leaves and developed the optimal extraction condition of the leaves to promote its application in food industry as a new food source.

Turmeric and chicory seed have beneficial effects on obesity markers and lipid profile in non-alcoholic fatty liver disease (NAFLD)

In an attempt to investigate new strategies aimed at reducing risk factors of non-alcoholic fatty liver disease (NAFLD), effects of turmeric (Curcuma longa L.) and chicory seed (Cichorium intybus L.) supplementation was evaluated in these patients. In this double-blind, randomized, controlled clinical trial, 92 patients with NAFLD aged 20-60 year with body mass index (BMI) ranged 24.9-40 kg/m2 was randomly assigned to 4 groups as follows. 1) Turmeric supplementation (3 g/d) (n = 23, TUR); 2) Chicory seed supplementation (infused 9 g/d (4.5 g /100mL)) (n = 23, CHI); 3) Turmeric and chicory seed supplementation (3 g/d turmeric + infused 9 g/d chicory seed (n = 23, TUR + CHI); 4) Placebo (n = 23, PLA). All intervention periods were 12 weeks. Fasting blood samples, anthropometric measurements, dietary records and physical activity were collected at baseline and at the end of the trial. Significant decreases were observed in BMI and waist circumference (WC) of subjects in CHI and TUR + CHI groups, compared with PLA group (p < 0.05). Combination of turmeric and chicory seed significantly decreased serum alkaline phosphatase level (p < 0.05). Serum levels of HDL-C increased considerably in TUR and TUR + CHI groups (p < 0.05 vs. placebo). Turmeric supplementation alone and plus chicory seed led to significant reduction in serum levels of TG/HDL-C and LDL-C/HDL-C ratio in TUR and TUR + CHI groups in comparison with placebo (p < 0.05). In conclusion, turmeric and chicory seed supplementation can be significantly useful in management of NAFLD risk factors.

Protective Effect of Curcuma Against Chromium Hepatotoxicity in Rats

This study was carried out to investigate the antioxidant effects of curcuma against chromium-induced alterations in hepatic indices and dysfunctions in the antioxidant system. Forty male Wistar rats were randomly divided into four groups and were treated for 30 consecutive days. The control group (0-0) received per os mineral water and normal diet. The second group (0-Cur) received mineral water and an experimental diet containing 2% of curcuma powder, whereas the third group (Cr-0) was orally fed (per os) with 15 mg/kg body weight/day of potassium dichromate and normal diet. The last group (Cr-Cur) received per os 15 mg/kg of potassium dichromate and a diet with 2% of curcuma. The treatment by chromium was found to elicit a perturbation in biochemical parameters producing a significant increase in glycemia, triglycerides, cholesterol, ALP, ALT, AST, and LDH levels. On the contrary, a significant reduction was observed in the oxidative stress-related parameters (GSH, GPx, CAT, and GST). Moreover, we noticed that liver sections of rats intoxicated with chromium showed a disrupted architecture. However, the administration of curcuma revealed an intense reduction in the oxidative stress induced by chromium, ameliorating the levels of the majority of the previous parameters. The data of this study revealed the potent antioxidant effects of curcuma in reducing oxidative stress damage induced by the hexavalent chromium.

Spent turmeric reduces fat mass in rats fed a high-fat diet

Indigestible carbohydrates may improve obesity. Spent turmeric contains high levels of dietary fibre and resistant starch (RS), which have fermentation potential in vitro. We hypothesised that indigestible carbohydrates in spent turmeric might prevent obesity development. In the first study, rats were administered 10% turmeric powder (TP) or spent turmeric powder (STP) in a high-fat (HF) diet for 28 d. In the second study, rats were fed 10% STP in a HF diet with or without antibiotics for 15 d. In the third study, rats were treated with a STP-containing suspension. In study 1, the TP and STP diet increased the caecal short-chain fatty acid (SCFA) content compared to that of a control diet. The lower energy intake in the TP and STP group was strongly related to the decrease in visceral fat weight. In study 2, after caecal fermentation suppression with antibiotics, STP treatment decreased the visceral fat mass. In study 3, the plasma glucose levels and incremental area under the curve (AUC) after ingestion of a STP-containing suspension were lower than those after ingestion of suspension alone. These findings suggest the reduction of carbohydrate absorption during the gastrointestinal passage after TP and STP treatment. Our data indicate that the reduced obesity development in rats fed a HF diet may be attributed to the low metabolisable energy density of carbohydrates in the spent turmeric, independent of SCFA-mediated factors.

In vitro fermentation of spent turmeric powder with a mixed culture of pig faecal bacteria

The fermentation potential of spent turmeric was studied in in vitro swine faecal batch cultures. The spent turmeric residue (the enzyme-resistant fraction from spent turmeric, EST) was obtained through the use of the digestive enzymes amyloglucosidase and pancreatin and compared to cellulose and high-amylose starch (HAS) as carbon sources. EST showed significant increases in total anaerobes, bifidobacteria, lactobacilli and lactic acid bacteria populations compared to cellulose at 12, 24 and 48 h, and the total anaerobic level in the HAS group was significantly higher than that in the cellulose group at 24 and 48 h. However, a significant decrease in the coliform population was only found in the HAS group compared to the cellulose group at 48 h. The total short-chain fatty acid (SCFA) concentrations in the EST and HAS groups were significantly higher than that in the cellulose group at 12 h and 48 h. However, there was no significant difference in the total SCFA concentration between the EST and HAS groups at 12 h and 48 h. Ammonia and pH levels in the EST and HAS groups were significantly lower than those in the cellulose group at 24 and 48 h, but there was no significant difference between the EST and HAS groups. These results indicate that the fermentation potential of the enzyme-resistant fraction from spent turmeric is comparable to that of commercially established resistant starch.