Antioxidant effect of garlic and aged black garlic in animal model of type 2 diabetes mellitus

Changes in Garlic Quality during Fermentation under Different Conditions

One of the garlic processing methods is fermentation, which produces black garlic with completely different chemical, physical, sensory, culinary, and health-enhancing properties. Our study aimed to compare the influence of various processing conditions on the quality indicators of black garlic (BG). Samples of white garlic (WG) were placed in laboratory climatic chambers. BG1 samples were packed in plastic bags and vacuumed, BG2 and BG3 samples were packed in textile mesh bags. BG1 samples were fermented in 70% humidity at 50 °C for 28 days, BG2 samples in 85% humidity at 60 °C for 99 days, and BG3 samples in 80% humidity at 80 °C for 14 days. The dependence of changes in chemical composition, color, and texture of garlic on fermentation conditions was analyzed. Proximate composition analyses and antioxidant activity of WG and BG were performed using standard methods. It was established that regardless of the fermentation conditions, BG's chemical composition became richer than WG's. They significantly increased vitamin C content (1.5-5.8 fold), titratable acidity (14.7-21.0 fold), protein (1.4-3.2 fold), fiber (4.6-7.0 fold), and ash (1.2-3.9 fold) content, amount of total phenolic compounds (6.6-9.6 fold) and antioxidant activity (5.3-9.9 fold). Fermented garlic turned dark in color and soft and sticky in texture. The higher fermentation temperature (80 °C) but the shorter time (14 days) had the greatest positive effect on the quality of black garlic.

Anti-Cancer and Anti-Inflammatory Properties of Black Garlic

Black garlic (BG) is a fermented form of garlic (Allium sativum L.), produced at precisely defined temperatures, humidities, and time periods. Although garlic has been used for thousands of years, black garlic is a relatively new discovery. There are many bioactive compounds in black garlic that give it medicinal properties, including anti-inflammatory and anti-cancer properties. In our review article, we present scientific studies examining the anti-inflammatory and anti-cancer effects of black garlic. According to research, this effect is mainly due to the reduction in the production of pro-inflammatory cytokines, as well as the ability to scavenge free oxygen radicals and induce apoptosis. In addition, the phytochemicals contained in it have antiproliferative and antiangiogenic properties and inhibit the growth of cancer cells. Black garlic is a valuable source of biologically active substances that can support anti-inflammatory and anti-cancer therapy. Compared to Allium sativum, black garlic has fewer side effects and is easier to consume.

Current studies and potential future research directions on biological effects and related mechanisms of allicin

Allicin, a thiosulfonate extract from freshly minced garlic, has been reported to have various biological effects on different organs and systems of animals and human. It can reduce oxidative stress, inhibit inflammatory response, resist pathogen infection and regulate intestinal flora. In addition, dozens of studies also demonstrated allicin could reduce blood glucose level, protect cardiovascular system and nervous system, and fight against cancers. Allicin was widely used in disease prevention and health care. However, more investigations on human cohort study are needed to verify the biological or clinical effects of allicin in the future. In this review, we summarized the biological effects of allicin from previous outstanding and valuable studies and provided useful information for future studies on the health effects of allicin.

Evaluation of the Effect of Garlic Tablet as a Complementary Treatment for Patients with Diabetic Retinopathy

PURPOSE

The aim of this study was to investigate the effectiveness of garlic (Allium sativum L.) tablets as a complimentary herbal medication in diabetic macular edema.

METHODS

A total of 91 diabetic participants (117 eyes) with central involved macular edema underwent a double-blind randomized trial. The patients used garlic tablets (500 mg) (2 tab/day) or placebo for 4 weeks and subsequently were examined by an expert ophthalmologist. Clinical manifestations including the best-corrected visual acuity (BCVA, logMAR), central macular thickness (CMT, μm), and intraocular pressure (IOP) were measured as the main outcomes.

RESULTS

BCVA was significantly improved by a 0.18 decrease in mean logMAR value in the garlic-treated patients in comparison with 0.06 in the control ones (P value = 0.027). CMT was decreased in both groups by a 102.99 μm decrease in the garlic group compared to 52.67 μm in the placebo group, albeit in a nonsignificant manner (P value: 0.094). IOP was decreased in the garlic group by 1.03 mmHg (P value: 0.024) and increased by 0.3 mmHg (P value: 0.468) in the placebo group.

CONCLUSION

Our trial suggests that garlic supplements can improve visual acuity, decrease the CMT and lower the IOP, and can be considered as an adjuvant treatment in patients with diabetic macular edema. Garlic was satisfactorily tolerated in diabetic patients, and no significant adverse effect interrupting the safety profile was observed.

An Overview on the Therapeutic Function of Foods Enriched with Plant Sterols in Diabetes Management

Diabetes is one of the most significant health issues across the world. People identified with diabetes are more vulnerable to various infections and are at a greater risk of developing cardiovascular diseases. The plant-based food we consume often contains many sterol-based bioactive compounds. It is well documented that these compounds could effectively manage the processes of insulin metabolism and cholesterol regulation. Insulin resistance followed by hyperglycemia often results in oxidative stress level enhancement and increased reactive oxygen species production. At the molecular level, these changes induce apoptosis in pancreatic cells and hence lead to insulin insufficiency. Studies have proved that plant sterols can lower inflammatory and oxidative stress damage connected with DNA repair mechanisms. The effective forms of phyto compounds are polyphenols, terpenoids, and thiols abundant in vegetables, fruits, nuts, and seeds. The available conventional drug-based therapies for the prevention and management of diabetes are time-consuming, costly, and with life-threatening side effects. Thereby, the therapeutic management of diabetes with plant sterols available in our daily diet is highly welcome as there are no side effects. This review intends to offer an overview of the present scenario of the anti-diabetic compounds from food ingredients towards the therapeutic beneficial against diabetes.

Black Garlic and Its Bioactive Compounds on Human Health Diseases: A Review

Black garlic (BG) is a form of aged garlic obtained from raw garlic (Allium sativum) via Millard reaction under high temperature (60-90 °C) and humidity (70-90%) for a period of time. Several studies reported higher contents of water-soluble antioxidants compounds (S-allyl cysteine, S-allyl-mercapto cysteine), 5-hydroxymethylfurfural, organosulfur compounds, polyphenol, volatile compounds, and products of other Millard reactions compared to fresh garlic after the thermal processing. Recent studies have demonstrated that BG and its bioactive compounds possess a wide range of biological activities and pharmacological properties that preserve and show better efficacy in preventing different types of diseases. Most of these benefits can be attributed to its anti-oxidation, anti-inflammation, anti-obesity, hepatoprotection, hypolipidemia, anti-cancer, anti-allergy, immunomodulation, nephroprotection, cardiovascular protection, and neuroprotection. Substantial studies have been conducted on BG and its components against different common human diseases in the last few decades. Still, a lot of research is ongoing to find out the therapeutic effects of BG. Thus, in this review, we summarized the pre-clinical and clinical studies of BG and its bioactive compounds on human health along with diverse bioactivity, a related mode of action, and also future challenges.

The Effect of Garlic Tablets on the Endometriosis-Related Pains: A Randomized Placebo-Controlled Clinical Trial

Endometriosis is a common chronic inflammatory disease. Garlic contains components that have antiproliferative, anti-inflammatory, and antioxidative effects. The current study aimed to evaluate the effectiveness of garlic on endometriosis symptoms. This was a randomized placebo-controlled triple-blind clinical trial. A convenience sample of 60 women was randomly allocated into two groups. The intervention group received usual care supplemented with 400 mg garlic tablets, and the placebo group received identical placebo tablets. A four-part Visual Analogue Scale (VAS) was used to measure the severity of pains. The pains were measured on four occasions (before the intervention and on one-, two-, and three-month follow-ups). Data were analyzed using the t-test, chi-square, repeated measures ANOVA, and ANCOVA by SPSS 16. The overall severity of pain reduced from 6.51 ± 0.86 to 1.83 ± 1.25 in the intervention group (p < 0.05). It increased from 6.41 ± 1.12 to 6.65 ± 1.37 in the control group (p = 0.02). The repeated measures ANOVA showed that there is a significant difference in the change of pain scores between intervention and control groups (p < 0.001, np2 = 0.572). Garlic extract can reduce pelvic and back pain, dysmenorrhea, and dyspareunia which are important symptoms of endometriosis.

Improving the bioavailability and bioactivity of garlic bioactive compounds via nanotechnology

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future.

Contributions from Mexican Flora for the Treatment of Diabetes Mellitus: Molecules of Psacalium decompositum (A. Gray) H. Rob & Brettell

Diabetes mellitus (DM) is cited as a serious worldwide health problem that occupies second place in causes of annual mortality in Mexico. Among Mexican flora, nearly 300 plant species have been employed as hypoglycemic in popular use. Thus, their study entertains great relevance In this context, this work contributes a clear and timely review of the plant species utilized in Traditional Mexican Medicine and experimental biological models in which not only have the hypoglycemic properties of the extracts and the isolated compounds been considered, but also the anti-inflammatory and antioxidant properties, taking into account an integral focus based on the complex mechanisms involved in the pathogenesis and physiopathology of DM. Among the species reviewed, we highlight Psacalium decompositum (Asteraceae), due to the potent hypoglycemic, anti-inflammatory, and antioxidant activity of the sesquiterpenes identified as majority compounds isolated from the root, such as cacalol and cacalone that also possess the capacity of increasing insulin levels. In this manner, the present manuscript attempts to contribute necessary information for the future study of bioactive molecules that are useful in the treatment of DM, as well as also being a contribution to the knowledge and diffusion of Mexican Traditional Medicine.

Ameliorative effects of garlic oil on FNDC5 and irisin sensitivity in liver of streptozotocin-induced diabetic rats

OBJECTIVES

This study was aimed to investigate the effects of garlic oil (GO), an important natural constituent used in alleviating diabetes and its complications, on the expression levels of irisin and related genes.

METHODS

Thirty-two rats were divided into four groups: Control, Diabetes-Control, Diabetes+GO 100 mg/kg/day and Control+GO 100 mg/kg/day for 45 days. The measurements included: changes in liver Peroxisome proliferator-activated receptor-gamma-coactivator (PGC)-1α, Fibronectin Type-III-Domain-Containing5 (FNDC5), irisin expression, mRNA expression of p38 and TNF-α (Tumour necrosis factor-α), total-antioxidant-status (L-TAS; S-TAS), total-oxidant-status (L-TOS; S-TOS) in liver and serum, respectively.

KEY FINDINGS

There was a significant reduction in serum levels of irisin and S-TAS and expression of PGC-1α and FNDC5 in liver in Diabetes-control compared to Control-group, while a significant increase in serum levels of fasting blood glucose (FBG) and TOS, also p38 and TNF-α expressions in liver. In Diabetes+GO group, there was a significant increase in serum irisin and S-TAS, also expression of PGC-1α and FNDC5 in liver, while serum FBG, S-TOS levels, and mRNA expression of p38 and TNF-α in liver were decreased compared to Diabetes-control group (P < 0.05).

CONCLUSIONS

GO alleviated the diabetic liver injury by decreasing Oxidative-Stress parameters and regulation PGC-lα, FNDC5, irisin and P38, keeping the balance of TAS/TOS and TNF-α.

Types of garlic and their anticancer and antioxidant activity: a review of the epidemiologic and experimental evidence

Garlic, an Allium vegetable, contains rich flavonoids organosulfur compounds (OSCs) that have potent anticancer properties. The aim of the review is to provide an overview of the different types of garlic, their active compounds, and the potential anticancer benefits with a focus on antioxidant activity. Animal and cell line studies have provided convincing evidence that garlic and its organosulfur compounds inhibit carcinogenesis through a number of events including induction of apoptosis, inhibiting cellular proliferation, scavenging radical oxygen species (ROS), increasing the activities of enzymes such as glutathione S-transferase, and reducing tumor size. Epidemiological studies showed compelling evidence that garlic consumption is associated with decreased risk of colorectal cancer, but inconsistent evidence for stomach, breast, and prostate cancers. Studies also suggest that the presence and potency of garlic OSCs varies with respect to the preparation and form of garlic. Further epidemiological studies with information on garlic form consumed or preparation methods and molecular studies regarding its antioxidant mechanisms, such as increasing enzymatic and nonenzymatic antioxidants levels, are warranted.

Herbal therapy as a promising approach for regulation on lipid profiles: A review of molecular aspects

Impaired lipid profile is defined as abnormal plasma levels of low-density lipoprotein, triglycerides, and total cholesterol. This disease state is associated with the development and progression of various disorders, such as diabetes mellitus, cardiovascular diseases, and acute myocardial infarction. Globally, all of these disorders are related to a significant rate of death. Therefore, finding a suitable approach for the prevention and treatment of lipid profile-related disorders is in the spotlight. Recently, herbal therapy has been considered a promising therapeutic approach for the treatment of hyperlipidemia or its related disorders due to its safety and efficacy. Hereby, we address the potential benefits of some of these herbal compounds on different aspects of lipid profile and its abnormalities with a special focus on their underlying mechanisms. Using herbal products, such as teas and mushrooms, or their derivatives, Rosmarinus officinalis Linn, Curcuma longa, Green tea, Lippia triphylla, Lippia citriodora, Plantago asiatica L, Vine tea, and Grifola frondosa have been proved to exert several therapeutic impacts on lipid profile and its related disorders, and we would provide a brief review on them in this literature.

Evaluation of Bioactive and Physicochemical Properties of White and Black Garlic (Allium sativum L.) from Conventional and Organic Cultivation

The aim of this study was to evaluate the bioactive and physicochemical properties of white and black garlic (Allium sativum L.) from conventional and organic cultivation. Both white conventional (G) and organic (EG) garlic were processed during 45 days heat treatment at 70 °C temperature and 80% relative humidity. In black garlic (BG) samples the content of soluble solids, total reducing sugars, total polyphenol as well as antioxidant activity significantly (p < 0.05) increased (by about 33.5%, 60.5%, 118.4%, 125.8%, respectively), while a pH significantly (p < 0.05) decreased (by about 41.1%) as compared to white garlic samples. The study showed significant differences between colour of white and black garlic, both in the L*a*b* and RGB colour space, especially in the case of the L* parameter, indicating that the colour of garlic changed from white to dark brown or black during the thermal processing. All organic garlic samples had improved bioactive ingredients and antioxidant activity compared to conventional garlic for both fresh (unprocessed) and heat-treated black garlic. The production of black garlic, especially organic (EBG), allows one to obtain a product with higher amount of bioactive compounds, which can be widely used in the design of health-promoting functional food.

Influence of Thermal Processing on the Bioactive, Antioxidant, and Physicochemical Properties of Conventional and Organic Agriculture Black Garlic (Allium sativum L.)

This study examines the effect of fermentation processes (70 °C temperature; 80% humidity; 45 days) on the content of bioactive compounds (total polyphenols, selected phenolic acids, and flavonoids), antioxidant activity and physicochemical properties of conventional and organic garlic (Allium sativum L.). Raw garlic from conventional cultivation (GR) showed significantly lower content of phenolic components and antioxidant activity compared to raw garlic from organic cultivation (GREcol) (by 22.8% and 25.1%, respectively). The fermentation processes of the garlic from both the conventional (BG) and organic (BGEcol) cultivation significantly increased the content of total polyphenols (more than two times), phenolic acids (more than 1.5 times) and flavonoids (1.5 and 1.3 times, respectively). The garlic fermentation process also significantly increased antioxidant potential: two times for BG and three times for BGEcol. The content of bioactive compounds (total polyphenols, phenolic acids, and flavonoids) was significantly (p < 0.05) higher in organic black garlic (BGEcol) compared to conventional black garlic (BG). Heat treatment leading to changes in both the physicochemical, organoleptic and health-promoting properties allowed to obtain a new product gaining in sensory attractiveness and enabling a wide range of applications.

Anti-Diabetic Obesity Effects of Wasabia Japonica Matsum Leaf Extract on 45% Kcal High-Fat Diet-Fed Mice

The present study examined the effects of Wasabi leaf (WL) on 45% Kcal high-fat diet (HFD)-fed mild diabetic obese mice. In particular, the hepatoprotective (i.e., liver weight, histopathology of liver, serum aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltransferase) effects of 12 weeks of continuous oral administration of 250 mg/kg metformin, and 200, 100, or 50 mg/kg WL were investigated. In addition, the hypolipidemic (i.e., serum triglyceride, total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein levels), hypoglycemic (i.e., glycated hemoglobin, blood glucose and insulin levels, pancreatic weight, and immunohistochemical-histopathological analysis of the pancreas), and anti-obesity effects (i.e., body weight, mean food consumption, total and abdominal body fat mass, periovarian fat weight, and histopathology of the periovarian and abdominal wall adipocytes) were monitored. The liver and general antioxidant defense systems were also assessed by lipid metabolism-related gene expression. All diabetes manifestations and related complications, including obesity and non-alcoholic fatty liver disease (NAFLD), were dose-dependently reduced after 84 days of oral treatment with metformin or each of the three dosages of WL. In particular, 50 mg/kg WL showed effective suppression effects against HFD-induced diabetes and related complications of obesity, NAFLD, and hyperlipidemia, comparable to the effects of metformin.

Impact of steaming pretreatment process on characteristics and antioxidant activities of black garlic (Allium sativum L.)

Impact of steaming pretreatment processes on physical properties, bioactive compounds and antioxidant activities, of black garlics (Allium sativum L.) was studied. Steaming pretreatment at different times (0, 4 and 6 min) was conducted before incubating in 60 °C-incubator at different incubation times (0, 9 and 18 days). Different steaming pretreatment processes affected the color and hardness of black garlic differently, while total polyphenol content (TPC) and total flavonoid content (TFC) were also determined by the steaming pretreatment time used. TPC and TFC increased with increasing of incubating time, where the highest those bioactive compounds was observed from 18-day incubation, especially with 4 min of steaming pretreatment (p ≤ 0.05). Increase of those bioactive compounds was in accordance with increasing of DPPH radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP) of black garlic during incubation. In addition, black garlic obtained from 18-day incubation with steaming pretreated for 4 min revealed the optimum condition providing the black garlic with high in both DPPH and FRAP, compared with others (p ≤ 0.05). Therefore, steaming pretreatment could effectively improve the efficiency of black garlic production process by increase the generation rate of bioactive compounds as well as induce antioxidant properties of black garlic with shorten process time.

Garlic (Allium sativum) improves anxiety- and depressive-related behaviors and brain oxidative stress in diabetic rats

This study investigated the effects of garlic on anxiety- and depression-related behaviors and brain oxidative markers in streptozotocin (STZ)-induced diabetes in rats. Fifty-six male Wistar rats were randomly divided into seven experimental groups (n = 8/group): control, diabetic + saline, diabetic + garlic, diabetic + imipramine, and diabetic + diazepam groups. Animals received garlic homogenate (0.1, 0.25, and 0.5 g/kg) for 10 days. At the end of the treatments, anxiety- and depressive-related behaviors were evaluated by elevated plus maze (EPM) and forced swimming test (FST), respectively. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and malondialdehyde (MDA) levels were measured in the brain. Diabetic + garlic (0.5 g/kg) group showed lower anxiety- and- depressive-like behaviors as compared to the diabetic rats. Furthermore, garlic treatment (0.5 g/kg) attenuated MDA levels and enhanced SOD and GPx activities in the brain. Our findings indicate that garlic alleviates anxiety- and depression-related behaviors in the diabetic rats possibly by attenuation of brain oxidative stress.

Determination of S-Allylmercaptocysteine in Rat Plasma by LC-MS/MS and its Application to a Pharmacokinetics Study

In this work, a rapid, simple, sensitive and specific LC-MS/MS method was developed and validated for the quantification of S-Allylmercaptocysteine (SAMC) in plasma. After a simple sample procedure by one step protein precipitation with acetontrile, the samples were separated on Gemini-NX C18 column (2.1 mm i.d. 150 mm, 3 μm, Phenomenex). The mobile phase was composed of water-acetonitrile (20:80, v/v) at an isocratic flow rate of 0.3 mL/min. The developed method was validated based on the International Conference on Harmonization (ICH) guidelines. The results show that the method had satisfactory specificity, precision and accuracy in a linear range of 50-3,000 ng/mL for SAMC. The precision conformed to the acceptance criteria, and the lower limit of quantification was 50 ng/mL for the analyte. The plasma samples stored for 10 days or after two freeze-thaw cycles (-80°C) were stable. This method was successfully applied to a pharmacokinetics study of SAMC in rats. It was found that SAMC metabolized very quickly in rats and its plasma half-life was less than 5 min.

Formation, nutritional value, and enhancement of characteristic components in black garlic: A review for maximizing the goodness to humans

Black garlic (BG) is essentially a processed food and obtained through the transformation of fresh garlic (FG) (Allium sativum L.) via a range of chemical reactions (including the Maillard reaction) and microbial fermentation. This review provides the up-to-date knowledge of the dynamic and complicated changes in major components during the conversion of FG to BG, including moisture, lipids, carbohydrates (such as sugars), proteins, organic acids, organic sulfur compounds, alkaloids, polyphenols, melanoidins, 5-hydroxymethylfurfural, vitamins, minerals, enzymes, and garlic endophytes. The obtained evidence confirms that BG has several advantages over FG in certain product attributes and biological properties (especially antioxidant activity), and the factors affecting the quality of BG include the type and characteristics of FG and processing technologies and methods (especially pretreatments, and processing temperature and humidity). The interactions among garlic components, and between garlic nutrients and microbes, as well as the interplay between pretreatment and main manufacturing process, all determine the sensory and nutritional qualities of BG. Before BG is marketed as a novel snack or functional food, more research is required to fill the knowledge gaps related to quantitative monitoring of the changes in metabolites (especially those taste-active and/or biological-active substances) during BG manufacturing to maximize BG's antioxidant, anticancer, antiobesity, anti-inflammatory, immunostimulatory, anti-allergic, hepatoprotective, cardioprotective and oxidative stress-/hangover syndrome-reducing functions, and beneficial effects on memory/nervous systems. Assessments of the quality, efficacy, and safety of BG should be performed considering the impacts of BG production conditions, postproduction handling, and intake methods.

An Overview of Disease Burden, Mechanism, Traditional and Non-traditional Management of Type 2 Diabetes

Diabetes is a major global health problem leading to high morbidity, mortality, and economic burden. Diabetes is connected to complex social, environmental, and behavioral factors and requires multisectoral evidence-based strategies to reduce its incidence and prevalence. Here we attempt to connect existing diabetes data with the underlying mechanism of the disease, while touching disease processes and traditional management approaches for diabetes and its complications. The major objective of this manuscript is to examine the effect of nontraditional treatment modalities, e.g. non-pharmaceutical interventions, supplements, alternative and integrative therapies etc., on diabetes. We performed an extensive literature search and review using electronic databases (PubMed and Google Scholar) to examine recent and historical diabetes statistics, the underlying mechanism of the disease, traditional treatments, remission possibility, and finally, the role of alternative therapies and supplements in its management. We found that there is no sufficient evidence to make most of the alternative therapies the first line of management and prevention approach for diabetes. Long-term and large-scale studies are needed to evaluate the safety and efficacy of alternative medicine. We feel that this review could urge other health researchers to plan comprehensive studies to examine the role of alternative or newly-identified therapies in diabetes. Also, this information can be useful for diverse health professionals and policymakers in developing and implementing evidence-based strategies.

Utilization of Pectinase Cocktail and High Hydrostatic Pressure for the Production of Aged Black Garlic Juice with Improved Nutritional Value

In comparison with raw garlic, aged black garlic has been shown to display multiple pharmacological activities. We recently reported that pretreatment of pectinase cocktail with high hydrostatic pressure (HHP) before the process of aging garlic juice improves its antidiabetic activity and increases S-allylcysteine (SAC) content. Thus, this study was designed to investigate the influence of pectinase cocktail with HHP on the quality of aged black garlic juice formation and to identify the optimal manufacturing conditions. In the pretreatment step, garlic juice is heated at 55°C for 24 h. The contents of SAC and total polyphenols were increased with treatment of pectinase cocktail; this increase was greater under HHP processing. In contrast, the total flavonoid content was decreased in all pretreatment conditions. Garlic juice pretreated with pectinase cocktail and HHP had a significantly higher content of SAC in the early phase of aging than raw garlic juice, and the SAC was increased over time in both treatment groups. The total polyphenol content of garlic juice was significantly higher in the pretreatment group during the aging period, and the antioxidant activity of garlic juice showed a positive correlation with polyphenol content. Interestingly, HHP increased the enzymatic activity of the pectinase cocktail.

Hepatoprotective and Renoprotective Properties of Lovastatin-Loaded Ginger and Garlic Oil Nanoemulsomes: Insights into Serum Biological Parameters

Background and Objectives: Dyslipidemia is gaining much attention among healthcare professionals because of its high association with the malfunctioning of a number of normal physiological and metabolic processes in the body. Obesity is directly interconnected with dyslipidemia and is said to be a denouement of hyperlipidemia and, if left untreated, may lead to intense damage to organs that are directly involved in fat metabolism. The objective of this study was to investigate the synergistic antiobesity and anti-hyperlipidemic activities along with hepato- and renoprotective potential of nanoemulsomes (NES) of lovastatin (LTN)-loaded ginger (GR) and garlic (GL) oils. Materials and Methods: LTN nanoemulsomes co-encapsulated with GR oil and GL oil were prepared by a thin hydration technique. Eight-week-old male Wistar rats weighing 200-250 g were induced with hyperlipidemia via a high-fat diet (HFD) comprising 40% beef tallow. Body weight, serum biochemical lipid parameters, and those for liver and kidney functions, serum TC, LDL-C, vLDL-C, HDL-C, TG, atherogenic index (AI), ALT, AFT, ALP, γ-GT, total protein (TP), serum albumin and globulin ratio (A/G), serum creatinine, blood urea nitrogen (BUN) and blood urea, and histopathology of hematoxylin and eosin (H&E) stained liver and kidney sections of all aforementioned groups were examined in the treated animals. Results: Nanoemulsomes of LTN-loaded GR and GL oils provided synergistic effects with LTN, exerted better ameliorative actions in reducing serum TC, LDL-C, vLDL-C, triglycerides, and AI, and improved serum HDL-C levels. Serum ALT, AST, ALP, and γ-GT levels were in the normal range for nanoemulsome groups. H&E stained liver and kidney sections of these animals confirmed better hepatoprotective and renoprotective effects than LTN alone. Serum biochemical parameters for renal functions also claimed to be in the moderate range for nanoemulsome-treated groups. Conclusion: This study demonstrated that nanoemulsomes of LTN-loaded GR and GL oils synergistically provided better antihyperlipidemic, hepatoprotective, and renoprotective effects as compared to LTN alone.

Lactobacillus bulgaricus improves antioxidant capacity of black garlic in the prevention of gestational diabetes mellitus: a randomized control trial

Objectives:Lactobacillus bulgaricus may improve antioxidant capacity of black garlic in the prevention of gestational diabetes mellitus (GDM).

Methods: Black garlic was prepared with or without L. bulgaricus. Volatile and polysaccharides were analyzed by using LC-MS, Fourier Transform infrared (FTIR) and ¹³C nuclear magnetic resonance (NMR). The study design was parallel randomized controlled trial and 226 GDM patients were randomly assigned into BG (black garlic and L. bulgaricus) and CG (black garlic) groups, and allocation ratio was 1:1. The treatment duration was 40 weeks. Fasting blood glucose (FBG) and 1- and 2-h blood glucose (1hBG and 2hBG) after oral glucose tolerance test (OGTT) were detected. Antioxidant function of black garlic was determined by measuring plasma malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and total antioxidant capacity (T-AOC) in GDM patients. The comparison between two groups was made using two independent samples t test.

Results: The intake of nutrients was similar between two groups (P>0.05). L. bulgaricus promoted the transformation of the glucopyranoside to glucofuranoside. L. bulgaricus increased the abilities of black garlic for scavenging hydroxyl radicals, 2,2′-azino-bis (3-ethylbenzenthiazoline-6-sulfonic) acid (ABTS) and DPPH free radicals. L. bulgaricus reduced the levels of FBG, 1hBG and 2hBG, and incidence of perinatal complications (P<0.01). Plasma MDA level in the BG group was lower than in the CG group, whereas the levels of SOD, GSH-PX and T-AOC in the BG group were higher than in the CG group (P<0.01).

Conclusions:L. bulgaricus improves antioxidant capacity of black garlic in the prevention of GDM.

Influence of Variety and Storage Time of Fresh Garlic on the Physicochemical and Antioxidant Properties of Black Garlic

Black garlic is made from the fresh kind, submitting it to a controlled temperature (~65 °C) and humidity (>85 °C) for a prolonged period of time. The aim of this study was to assess the differences in the process and in the final product as a result of employing three garlic varieties (Spanish Roja, Chinese Spring and California White), and to check the influence of the storage time on fresh garlic in the quality of the final product by using garlic obtained in two different agricultural seasons, that of the current year (2014) and of the previous one (2013). The results revealed some differences in the parameters analysed during the manufacturing of the black garlic from the three varieties used, and even according to the harvest in question. However, when comparing initial and final values of the samples, a very similar evolution in their acidity, reducing sugars, °Brix, pH, polyphenol content, and antioxidant capacity was noted.

Effect of Aged Garlic Ethyl Acetate Extract on Oxidative Stress and Cholinergic Function of Scopolamine-Induced Cognitive Impairment in Mice

This study was performed to investigate the effect of aged black garlic ethyl acetate extract on scopolamine-induced cognitive impairment in mice. Aged garlic ethyl acetate extract (BG) was administrated at a dose of 25 or 50 mg/ kg in scopolamine-induced mice. Cognitive ability was evaluated using a Morris water maze test and a passive avoidance test. BGs (50 mg/kg) shortened the latency time that was increased by scopolamine and increased the platform crossing numbers that was significantly shortened by scopolamine after 5 days training in the Morris water maze test (P<0.05). BG (50 mg/kg) also significantly prolonged the latency time in the passive avoidance test (P<0.05). Result from biochemical analysis showed that BG increased levels of glutathione, glutathione peroxidase activity, and glutathione reductase activity, whereas BG significantly inhibited lipid peroxidation (P<0.05). BG also attenuated cholinergic degradation through inhibiting acetylcholinesterase activity and increasing choline acetyltransferase activity (P<0.05). In conclusion, BG protected against scopolamine-induced cognitive impairment through decreasing oxidative damage and regulating cholinergic function in the brains of mice. BG may therefore be a beneficial food for protecting against neurodegeneration such as Alzheimer’s disease.

Physicochemical Characterization and Biological Activities of Black and White Garlic: In Vivo and In Vitro Assays

White and three types of black garlic (13, 32, and 45 days of aging, named 0C1, 1C2, and 2C1, respectively) were selected to study possible differences in their nutraceutic potential. For this purpose, garlic were physicochemically characterized (Brix, pH, aW, L, polyphenol, and antioxidant capacity), and both in vivo and in vitro assays were carried out. Black garlic samples showed higher polyphenol content and antioxidant capacity than the white ones. The biological assays showed that none of the samples (neither raw nor black garlic) produced toxic effects in the Drosophila melanogaster animal genetic model, nor exerted protective effects against H₂O₂, with the exception of the 0C1 black garlic. Moreover, only white garlic was genotoxic at the highest concentration. On the other hand, 0C1 black garlic was the most antigenotoxic substance. The in vivo longevity assays showed significant extension of lifespan at some concentrations of white and 0C1and 1C2 black garlic. The in vitro experiments showed that all of the garlic samples induced a decrease in leukemia cell growth. However, no type of garlic was able to induce proapoptotic internucleosomal DNA fragmentation. Taking into account the physicochemical and biological data, black garlic could be considered a potential functional food and used in the preventive treatment of age-related diseases. In addition, our findings could be relevant for black-garlic-processing agrifood companies, as the economical and timing costs can significantly be shortened from 45 to 13 days of aging.

The aqueous extract of aged black garlic ameliorates colistin-induced acute kidney injury in rats

The use of colistin in the treatment of multidrug-resistant Gram-negative bacterial infections is restricted due to nephrotoxicity. We investigated the effects of aged black garlic extract (ABGE) on colistin-induced kidney injury in rats. Rats were assigned to four groups. Normal saline was intraperitoneally and intragastrically injected for control group. ABGE was intragastrically injected for garlic group. Ten mg/kg of colistin was intraperitoneally injected for 6 consecutive days for colistin group. One percent of ABGE was done 30 min prior to colistin injection for treatment group. Rats were sacrificed on the next day after last colistin injection. Colistin injection increased the serum levels of blood urea nitrogen and creatinine; however, ABGE prevented deterioration of these serum levels. ABGE also alleviated tubular damage, including vacuolation and necrosis. TUNEL-positive cells were observed less frequently for the ABGE-treated groups. CD68 positive cells were significantly decreased by pretreatment with ABGE. Levels of oxidative stress biomarkers such as 8-hydroxydeoxyguanosine and malondialdehyde were lower in the ABGE-treated groups. Levels of NF-κB, inducible NO synthase, COX-2, and TGF-β1 were lower in rats that had been treated with ABGE injection. Renal levels of IL-1β and TNF-α were increased by colistin administration whereas renal SOD, catalase, and GSH levels were restored by ABGE administration. These results suggest that ABGE, which has antioxidant and anti-inflammatory properties, might be a potential therapeutic agent to prevent renal toxicity of colistin.

Beneficial Effects of an Aged Black Garlic Extract in the Metabolic and Vascular Alterations Induced by a High Fat/Sucrose Diet in Male Rats

Aged black garlic (ABG) is a functional food with antioxidant and anti-inflammatory properties. Recent studies also report its beneficial metabolic effects in a context of obesity or diabetes, although the mechanisms involved are poorly understood. The aim of this work was to analyze the effects of an ABG extract in the vascular and metabolic alterations induced by a high-fat/sucrose diet in rats. For this purpose, male Sprague–Dawley rats were fed either a standard chow (controls; n = 12) or a high-fat/sucrose diet (HFD; n = 24) for 16 weeks. From week 8 on, half of the HFD rats were treated with a commercial ABG extract concentrated in S-allyl cysteine and melanoidins (ABG10+®; 250 mg/kg daily by gavage; 5 mL/kg). ABG10+®-treated rats showed lower mean caloric intake, body weight, triglycerides, low density lipoprotein cholesterol (LDL-c), insulin and leptin serum concentrations and higher high density lipoprotein cholesterol (HDL-c) and adiponectin serum concentrations than non-treated rats. In the hypothalamus, ABG10+® treatment induced an increase in the gene expression of proopiomelanocortin (POMC) and a decrease in leptin receptor (ObR) mRNA levels. No significant changes were found in visceral adipose tissue except for an overexpression of β3-adrenergic receptor (β3-ADR) in ABG-treated rats. In subcutaneous adipose tissue, ABG10+® treatment decreased adipose weight and downregulated the gene expression of PPAR-γ, LPL, ObR and HSL. In brown adipose tissue, an overexpression of InsR, GLUT-4, UCP-1 and β3-ADR in ABG10+®-treated rats was found, whereas PPAR-γ mRNA levels were significantly decreased. Regarding vascular function, ABG10+® treatment attenuated the obesity-induced vasoconstriction in response to potassium chloride both in presence/absence of perivascular adipose tissue (PVAT). On the contrary, aorta segments from ABG-treated rats showed and improved relaxation in response to acetylcholine only when PVAT was present, with this fact possible being related to the decreased gene expression of proinflammatory cytokines in this tissue. In conclusion, ABG10+® administration partially improves the metabolic and vascular alterations induced by a high-fat/high-sucrose diet in rats through modifications in the gene expression of proteins and neuropeptides involved in inflammation, fat metabolism and food intake regulation. Further studies are required to assess the bioavailability of ABG between rats and humans.

Amelioration of Single Clove Black Garlic Aqueous Extract on Dyslipidemia and Hepatitis in Chronic Carbon Tetrachloride Intoxicated Swiss Albino Mice

Single clove garlic is the product of atypical bulbing process of garlic under specific conditions. Therefore, the number of researches on single clove garlic bioactivity is limited. Recently, the hepatoprotective effect of single clove garlic has been demonstrated. In this study, we investigated amelioration of single clove black garlic aqueous extract, a processed product from single clove garlic, on dyslipidemia and hepatitis induced by chronic administration of CCl₄. Mice were randomly divided into four groups: control, extract control, CCl₄ intoxication, and coadministrated CCl₄ and extract group. Mice were orally given a dose of 1 ml/kg body weight of CCl₄ for 28 days twice a week to establish chronic liver injury model. To evaluate the hepatoprotective effect of single clove black garlic, mice were cotreated with CCl₄ and single clove black garlic extract (200 mg/kg body weight) via gastric gauge for 30 days. Cotreatment with CCl₄ and extract could improve the changes of body weight, liver weight, and relative liver weight as compared to CCl₄ intoxicated mice. Single clove black garlic ameliorated dyslipidemia and the elevation of ALT and AST levels induced by chronic CCl₄ intoxication. Histological studies revealed that single clove black garlic could prevent mononuclear cells infiltration and hepatocyte necrosis.

Aged (Black) versus Raw Garlic against Ischemia/Reperfusion-Induced Cardiac Complications

Recent evidence from studies suggests that aged black garlic also has an effect on health. The major aim of the present study is to compare the effect of raw and aged black garlic on postischemic cardiac recovery. Male Sprague Dawley rats were randomly divided into three groups. Animals of the first group were fed with raw garlic, animals of the second group received aged black garlic, while the third group served as vehicle-treated controls. Upon conclusion of the treatment, isolated hearts were undertaken to ischemia/reperfusion. Heart function and infarct size were measured and the level of HO-1 and iNOS were studied. Superior postischemic cardiac function and reduced infarct size in both garlic treated groups compared to the drug-free control group, indicated cardioprotective effects. However, no significant differences between the garlic treated groups were observed. Western blot analysis revealed that raw garlic enhanced the level of HO-1 before ischemia, while in ischemic samples, we found elevated HO-1 expression in both garlic treated groups. The level of iNOS was the same before ischemia in all groups, however, a markedly reduced iNOS level in ischemic/reperfused hearts originating from control and raw garlic treated animals was observed. Samples from aged black garlic treated animals demonstrated that the level of iNOS was not significantly reduced after ischemia/reperfusion. Taken together these results indicate that not only raw but also aged black garlic possess a cardioprotective effect.

Protective effect of black garlic extracts on tert-Butyl hydroperoxide-induced injury in hepatocytes via a c-Jun N-terminal kinase-dependent mechanism

Black garlic has been reported to show multiple bioactivities against the development of different diseases. In the present study, the hepatoprotective effect of black garlic on injured liver cells was investigated. Rat clone-9 hepatocytes were used for all experiments; tert-Butyl hydroperoxide (tBHP) was used to induce injury of rat clone-9 hepatocytes. The contents of malondialdehyde (MDA) and glutathione (GSH); anti-oxidative enzyme activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx); and mRNA expression levels of interleukin (IL)-6 and IL-8 in rat clone-9 hepatocytes were determined to evaluate the level of cell damage. Black garlic extracts were demonstrated to significantly attenuate tBHP-induced cell death of rat clone-9 hepatocytes (P<0.05). Pretreatment with black garlic extracts antagonized GSH depletion, tBHP-increased MDA accumulation and the mRNA expression level of IL-6/IL-8, and tBHP-decreased antioxidative enzyme activities (all P<0.05). Moreover, the present study revealed that c-Jun N-terminal kinase signaling regulated black garlic-inhibited tBHP effects in rat clone-9 hepatocytes. Our findings demonstrate that black garlic has the hepatoprotective potential to block tBHP-damaged effects on cell death, lipid peroxidation, oxidative stress, and inflammation in rat clone-9 hepatocytes. Thus, the present study indicates that black garlic may be an excellent natural candidate in the development of adjuvant therapy and healthy foods for liver protection.

Characterization of microbial community structure and metabolic potential using Illumina MiSeq platform during the black garlic processing

Black garlic is a distinctive garlic deep-processed product made from fresh garlic at high temperature and controlled humidity. To explore microbial community structure, diversity and metabolic potential during the 12days of the black garlic processing, Illumina MiSeq sequencing technology was performed to sequence the 16S rRNA V3-V4 hypervariable region of bacteria. A total of 677,917 high quality reads were yielded with an average read length of 416bp. Operational taxonomic units (OTU) clustering analysis showed that the number of species OTUs ranged from 148 to 1974, with alpha diversity increasing remarkably, indicating the high microbial community abundance and diversity. Taxonomic analysis indicated that bacterial community was classified into 45 phyla and 1125 distinct genera, and the microbiome of black garlic samples based on phylogenetic analysis was dominated by distinct populations of four genera: Thermus, Corynebacterium, Streptococcus and Brevundimonas. The metabolic pathways were predicted for 16S rRNA marker gene sequences based on Kyoto Encyclopedia of Genes and Genomes (KEGG), indicating that amino acid metabolism, carbohydrate metabolism and membrane transport were important for the black garlic fermentation process. Overall, the study was the first to reveal microbial community structure and speculate the composition of functional genes in black garlic samples. The results contributed to further analysis of the interaction between microbial community and black garlic components at different stages, which was of great significance to study the formation mechanism and quality improvement of black garlic in the future.

Characterization of garlic endophytes isolated from the black garlic processing

The objectives of this study were to isolate and identify garlic endophytes, and explore the characteristics of dominant strains. Garlic endophytes were studied through phenotypical characterization and comparative sequence analysis of 16S rDNA based on culture‐dependent approaches. Representative strains inferred from 16S rDNA sequencing were selected for further identification by gyrA and rpoB gene loci and phylogenetic analysis based on concateneted house‐keeping sequences. Seven kinds of Bacillus were found from garlic and black garlic, respectively. Further studies demonstrated that the total bacteria and endophytes showed a sharp decrease firstly, followed by a rapid rise, then maintained at a certain level, and finally slowed down during the black garlic processing. B. subtilis, B. methylotrophicus, and B. amyloliquefaciens were the dominant strains. The selected strains were capable of fermenting glucose, lactose, sucrose, and garlic polysaccharide to produce acid but no gas, with a strong ability of heat resistance. The results indicated that there were a certain number of garlic endophytes during the black garlic processing, and Bacillus was the dominant strains under the conventional culture‐dependent methods. This report provided useful information for the presence and type of garlic endophytes during the black garlic processing, which were of great significance to study the formation mechanism and quality improvement of black garlic in the future, as well as the security of garlic powder.

Anti-obesity effects of yellow catfish protein hydrolysate on mice fed a 45% kcal high-fat diet

Obesity contributes to the etiologies of a variety of comorbid conditions, such as type 2 diabetes, hypertension and cardiovascular disease. In the present study, the anti-obesity effects of yellow catfish protein hydrolysate (YPh) were observed in mice fed a 45% kcal high-fat diet (HFD) compared with those of mice treated with simvastatin. The HFD-fed control mice exhibited noticeable increase in body weight, and whole-body and abdominal fat densities, periovarian and abdominal wall-deposited fat pad weight, as well as in the levels of triglycerides (TG), blood total cholesterol (TC), low-density lipoprotein, alanine aminotransferase, aspartate aminotransferase, creatinine, blood urea nitrogen, and in the fecal TG and TC contents. However, they exhibited a decrease in serum high-density lipoprotein levels. In addition, an increase was detected in periovarian and dorsal abdominally deposited fat pad thickness, adipocyte hypertrophy, the number of steatohepatitis regions, hepatocyte hypertrophy and lipid droplet deposition-related renal tubular vacuolation degenerative lesions, along with increased hepatic lipid peroxidation and a deteriorated endogenous antioxidant defense system (glutathione, catalase and superoxide dismutase). However, all the above-mentioned obesity-related complications were dose-dependently and significantly inhibited after 84 days of thye consecutive oral administration of 125, 250 and 500 mg/kg YPh. In addition, YPh dose-dependently depleted the liver endogenous antioxidant defense system and inhibited hepatic lipid peroxidation. Overall, the effects of 250 mg/kg YPh on HFD-induced obesity and related complications were similar or more potent than those of 10 mg/kg simvastatin. These results indicate that YPh is a promising new potent medicinal ingredient for possible use in the treatment of obesity and related complications.