Onion (Allium cepa L.) peel extract effects on 3T3-L1 adipocytes and high-fat diet-induced obese mice

The Immune-Stimulating and Anti-Diabetic Effects of Allium hookeri Leaves Grown in a Plant Factory with Artificial Lights in Immunosuppressed Obese C57BL/6 Mice

We investigated the immune-stimulating and anti-diabetic effects of Allium hookeri leaves grown in a plant factory with artificial lights. The immunomodulatory effects of A. hookeri leaves' ethanol extracts were evaluated with immune-related hematological factors in blood, the proliferation of splenocytes, NK cell activity, IgG and cytokine levels, and their mechanisms in immunosuppressed obese mice. Anti-diabetic effects were determined by the inhibitory activity against α-amylase and α-glucosidase in vitro and fasting blood glucose levels and biochemical factors in the serum of immunosuppressed obese mice. A. hookeri leaf extracts increased WBC and LYM counts, the proliferation of splenocytes, and serum IgG and IL-1β concentrations compared to those of the NC group, which was used as a negative control. A. hookeri leaf extracts also improved serum HDL levels while they decreased the activities of digestive enzymes, fasting blood glucose, and biochemical factors (ALT, AST, T-Chol, TG, LDL, and GLU). The expressions of IL-1β, JNK, c-Jun, p65, and iNOS in the thymus of immunosuppressed mice were activated by the treatment of A. hookeri leaf extracts. The results suggest that A. hookeri leaves grown in a plant factory with artificial lights also have immune-stimulatory and anti-diabetic effects and can be used as novel functional supplements to control related diseases and to improve public health.

Onion supplementation and health metabolic parameters: A systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Functional foods, such as onions, have been the center of many recent investigations. In this systematic-review and meta-analysis, we aimed to gather up the existing information with regard to the impact of onion supplementation on anthropometric measurements/indices, lipid profile, indices of glycemic control and hepatic health, systolic and diastolic blood pressures (SBP and DBP), and adiponectin and leptin.

METHODS

All major online datasets (PubMed, Web of Science, Cochrane, and Scopus) were thoroughly searched from inception up to October 2022. Relevant randomized controlled trials (RCTs) were obtained using the eligibility criteria. Weighted mean differences (WMDs) were calculated and reported. Statistical significance was set as p-values <0.05.

RESULTS

Among all the retrieved data, 14 RCTs were eligible to be included. The results of the crude analysis showed that onion supplementation significantly improved body fat percentage (BFP), low-density lipoprotein-cholesterol (LDL-c), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-c), systolic blood pressure, adiponectin, and aspartate aminotransferase (AST). Subgroup analysis revealed that interventions lasting more than 12 weeks can significantly alter weight, waist circumference (WC), body mass index (BMI), BFP, LDL-c, TC, SBP, and DBP. Moreover, the intake of dosages of >300 mg/day of onion supplementation could significantly improve weight, WC, BMI, BFP, LDL-c, HDL-C, TC, AST, ALT, SBP and DBP.

CONCLUSION

It seems that the intake of onion supplementation can improve health metabolic parameters. We observed that with either longer follow-up periods or higher dosages of onion supplementation, improvements in cardio-metabolic parameters could be expected.

Potential of enhancing anti-obesogenic agriceuticals by applying sustainable fertilizers during plant cultivation

Overweight and obesity are two of the world's biggest health problems. They are associated with excessive fat accumulation resulting from an imbalance between energy consumed and energy expended. Conventional therapies for obesity commonly include synthetic drugs and surgical procedures that can lead to serious side effects. Therefore, developing effective, safe, and readily available new treatments to prevent and treat obesity is highly relevant. Many plant extracts have shown anti-obesogenic potential. These plant extracts are composed of different agriceuticals such as fibers, phenolic acids, flavonoids, anthocyanins, alkaloids, lignans, and proteins that can manage obesity by suppressing appetite, inhibiting digestive enzymes, reducing adipogenesis and lipogenesis, promoting lipolysis and thermogenesis, modulating gut microbiota and suppressing obesity-induced inflammation. These anti-obesogenic agriceuticals can be enhanced in plants during their cultivation by applying sustainable fertilization strategies, improving their capacity to fight the obesity pandemic. Biofertilization and nanofertilization are considered efficient, eco-friendly, and cost-effective strategies to enhance plant growth and development and increase the content of nutrients and bioactive compounds, representing an alternative to overproducing the anti-obesogenic agriceuticals of interest. However, further research is required to study the impact of anti-obesogenic plant species grown using these agricultural practices. This review presents the current scenario of overweight and obesity; recent research work describing different plant species with significant effects against obesity; and several reports exhibiting the potential of the biofertilization and nanofertilization practices to enhance the concentrations of bioactive molecules of anti-obesogenic plant species.

Health-promoting foods and food crops of West-Africa origin: The bioactive compounds and immunomodulating potential

The rural communities of the sub-Sahara regions in Africa are rich in diverse indigenous culinary knowledge and foods, food crops, and condiments such as roots/tubers, cereal, legumes/pulses, locust beans, and green leafy vegetables. These food crops are rich in micronutrients and phytochemicals, which have the potentials to address hidden hunger as well as promote health when consumed. Some examples of these are fermented foods such as ogi and plants such as Vernonia amygdalina (bitter leaf), Zingiber officinales (garlic), Hibiscus sabdariffa (Roselle), and condiments. Food crops from West Africa contain numerous bioactive substances such as saponins, alkaloids, tannins, phenolics, flavonoids, and monoterpenoid chemicals among others. These bioresources have proven biological and pharmacological activities due to diverse mechanisms of action such as immunomodulatory, anti-inflammatory, antipyretic, and antioxidant activities which made them suitable as candidates for nutraceuticals and pharma foods. This review seeks to explore the different processes such as fermentation applied during food preparation and food crops of West-African origin with health-promoting benefits. The different bioactive compounds present in such food or food crops are discussed extensively as well as the diverse application, especially regarding respiratory diseases. PRACTICAL APPLICATIONS: The plants and herbs summarized here are more easily accessible and affordable by therapists and others having a passion for promising medicinal properties of African-origin plants.The mechanisms and unique metabolic potentials of African food crops discussed in this article will promote their applicability as a template molecule for novel drug discoveries in treatment strategies for emerging diseases. This compilation of antiviral plants will help clinicians and researchers bring new preventive strategies in combating COVID-19 like viral diseases, ultimately saving millions of affected people.

The Phytochemical and Nutritional Composition of Shallot Species (Allium × cornutum, Allium × proliferum and A. cepa Aggregatum) Is Genetically and Environmentally Dependent

Shallots are a perennial plant from the Alliaceae family, classified with the common onion under the name of the Allium cepa Aggregatum group. The term shallot is also used for diploid and triploid viviparous onions, known as Allium × proliferum (Moench) Schrad and Allium × cornutum Clementi ex Vis., respectively. In this study, we compared the dry matter, pyruvic acid content, sugar content, flavonoid content, antioxidant capacity and mineral composition of 34 shallot accessions falling into three shallot species (Allium × cornutum, Allium × proliferum and A. cepa Aggregatum). Shallot accessions belonging to the A.× cornutum and A. × proliferum groups are characterized by high dry matter content (around 25%), of which a little less than 50% is formed of inulin-type sugars, polysaccharides, considered an excellent prebiotic with beneficial effects on human health. On the other hand, accessions belonging to the A. cepa Aggregatum group have lower dry matter content and, as a result, lower pungency (measured as pyruvic acid content), making them more suitable for fresh consumption by a broader range of consumers, but, at the same time, abundant in phenolic compounds, especially quercetin and isorhamnetin glycosides. We also observed a greater biodiversity among accessions within the A. cepa Aggregatum group in all the analyzed physico-chemical parameters compared to the other shallot groups. The investigated shallot accessions have an excellent in vitro antioxidant capacity, as well as excellent nutritional properties.

Effects of Onion Extract and Onion Peel Extract on the Formation of Polycyclic Aromatic Hydrocarbons in Charcoal-Grilled Pork Patties

ABSTRACT

This study investigated the effects of different concentrations (0.0005, 0.005, 0.05, 0.25, and 0.5%) of onion extract (OE) and onion peel extract (OPE) on the formation of four polycyclic aromatic hydrocarbons (PAHs) in charcoal-grilled pork patties. Both OE and OPE inhibited the formation of four PAHs in charcoal-grilled pork patties, with the highest inhibition rate reaching 88.33% on 0.50% OE addition and 98.79% on 0.05 and 0.25% OPE addition. OPE has greater inhibitory effect on the formation of four PAHs than OE does; this may be related to OPE's higher concentrations of flavonoids and higher free-radical scavenging activities. Both OE and OPE worked to lower thiobarbituric acid reactive substance values of charcoal-grilled pork patties. The inhibitory effect of OE and OPE on four PAHs showed the same trend as their antilipid oxidation effects, but the correlation was not strong. In addition to antilipid oxidation, other pathways are also involved in the inhibition of PAH formation.

HIGHLIGHTS

Onion (Allium cepa L.) peels: A review on bioactive compounds and biomedical activities

Huge quantities of byproducts/wastes generated in onion processing are usually discarded, but they are excellent sources of bioactive compounds and phytochemicals. However, with growing interest in the sustainable use of resources and the circular economy to reduce adverse impacts on the environment, food processing wastes such as onion peel/skin can be extracted and employed as inputs in developing or reformulating nutrient supplements, and pharmacological drugs. This review highlights major bioactive components, especially total phenolics, total flavonoid, quercetin and its derivatives present in onion peel/skin and their therapeutic applications as cardioprotective, neuroprotective, antiobesity, antidiabetic, anticancer and antimicrobial agents. The present review emphasized that onion peel is one of the important agricultural by-products which is rich in bioactive compounds and can be utilized as health promoting ingredient especially in pharmacological and biomedical fields. Thus, with increasing burden of life style disorders/non-communicable diseases, finding suitable natural alternative for their treatment is one major concern of the researchers and onion peel and its extract can be exploited as a prime ingredient.

Natural Dietary and Medicinal Plants with Anti-Obesity Therapeutics Activities for Treatment and Prevention of Obesity during Lock Down and in Post-COVID-19 Era

Overweight and obesity have become global epidemics, especially during the lockdown due to the COVID-19 pandemic. The potential of medicinal plants as a better and safe option in treating obesity and overweight has gained attention in recent years. Obesity and overweight has become a major public health concern, and its incidence rising at an alarming rate. Obesity is one of the major types of metabolic syndrome, resulting in various types of problems such as hypertension, diabetes, dyslipidemia, and excess fat accumulation. The current searching was done by the keywords in main indexing systems including Scopus, PubMed/MEDLINE, the search engine of Google Scholar, and Institute for Scientific Web of Science. The keywords were traditional medicine, health benefits, pharmaceutical science, pomegranate, punicalin, punicalagin, and ellagitannins. Google Scholar was searched manually for possible missing manuscripts, and there was no language restriction in the search. This review was carried out to highlight the importance of medicinal plants which are common in traditional medicinal sciences of different countries, especially Asia to prevent and treatment of obesity and overweight during the global pandemic and the post-COVID-19 era.

Recent Advances in Bioactive Compounds, Health Functions, and Safety Concerns of Onion (Allium cepa L.)

Onion (Allium cepa L.) is a common vegetable, widely consumed all over the world. Onion contains diverse phytochemicals, including organosulfur compounds, phenolic compounds, polysaccharides, and saponins. The phenolic and sulfur-containing compounds, including onionin A, cysteine sulfoxides, quercetin, and quercetin glucosides, are the major bioactive constituents of onion. Accumulated studies have revealed that onion and its bioactive compounds possess various health functions, such as antioxidant, antimicrobial, anti-inflammatory, anti-obesity, anti-diabetic, anticancer, cardiovascular protective, neuroprotective, hepatorenal protective, respiratory protective, digestive system protective, reproductive protective, and immunomodulatory properties. Herein, the main bioactive compounds in onion are summarized, followed by intensively discussing its major health functions as well as relevant molecular mechanisms. Moreover, the potential safety concerns about onion contamination and the ways to mitigate these issues are also discussed. We hope that this paper can attract broader attention to onion and its bioactive compounds, which are promising ingredients in the development of functional foods and nutraceuticals for preventing and managing certain chronic diseases.