Botrytis fruit rot management: What have we achieved so far?

Botrytis cinerea is a destructive necrotrophic phytopathogen causing overwhelming diseases in more than 1400 plant species, especially fruit crops, resulting in significant economic losses worldwide. The pathogen causes rotting of fruits at both pre-harvest and postharvest stages. Aside from causing gray mold of the mature fruits, the fungus infects leaves, flowers, and seeds, which makes it a notorious phytopathogen. Worldwide, in the majority of fruit crops, B. cinerea causes gray mold. In order to effectively control this pathogen, extensive research has been conducted due to its wide host range and the huge economic losses it causes. It is advantageous to explore detection and diagnosis techniques of B. cinerea to provide the fundamental basis for mitigation strategies. Botrytis cinerea has been identified and quantified in fruit/plant samples at pre- and post-infection levels using various detection techniques including DNA markers, volatile organic compounds, qPCR, chip-digital PCR, and PCR-based nucleic acid sensors. In addition, cultural, physical, chemical, biological, and botanical methods have all been used to combat Botrytis fruit rot. This review discusses research progress made on estimating economic losses, detection and diagnosis, as well as management strategies, including cultural, physical, chemical, and biological studies on B. cinerea along with knowledge gaps and potential areas for future research.

Characterizations of Ganoderma species causing basal stem rot disease in coconut tree.

The basal stem rot disease incidence ranged from 0 to 5% in Karnataka India during the year 2019-20. Twenty pathogenic isolates of Ganoderma sp varied with cultural characteristics and virulence on coconut seedlings of the variety Tipatur Tall. The identity of each isolate was confirmed through morphological characters and through ITS sequencing. Two isolates viz., G4 and G5 were identified as Ganoderma applanatum and remaining all isolates were identified as G. lucidum. The genetic diversity analysis of Ganoderma isolates was done using ten Random Amplified Polymorphic DNA (RAPD) and fifteen Inter Simple Sequence Repeat (ISSR) primers. Among the ten RAPD primers, only eight primers recorded polymorphism (33.30-66.70%). The primer SBS-Q3 exhibited the highest polymorphism of 66.70%. In case of ISSR primers, all primers recorded polymorphism (33.30-60.00%). The primer UBC866 was the most polymorphic primer with 60.0% polymorphism. RAPD and ISSR markers were compared for their efficacy in assessing the genetic diversity by taking the band frequency, Shannon's index, polymorphic information content, resolving power, and mean resolving power into consideration, and it was concluded that ISSR was marker of choice over RAPD. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03872-w.

Exploiting root exudates to manage soil-borne disease complexes in a changing climate.

Ongoing climate change will both profoundly impact land-use (e.g., changes in crop species or cultivar and cropping practices) and abiotic factors (e.g., moisture and temperature), which will in turn alter plant-microorganism interactions in soils, including soil-borne pathogens (i.e., plant pathogenic bacteria, fungi, oomycetes, viruses, and nematodes). These pathogens often cause soil-borne disease complexes, which, due to their complexity, frequently remain undiagnosed and unmanaged, leading to chronic yield and quality losses. Root exudates are a complex group of organic substances released in the rhizosphere with potential to recruit, repel, stimulate, inhibit, or kill other organisms, including the detrimental ones. An improved understanding of how root exudates affect interspecies and/or interkingdom interactions in the rhizosphere under ongoing climate change is a prerequisite to effectively manage plant-associated microbes, including those causing diseases.

Antitubercular drugs: possible role of natural products acting as antituberculosis medication in overcoming drug resistance and drug-induced hepatotoxicity.

Mycobacterium tuberculosis (Mtb) is a pathogenic bacterium which causes tuberculosis (TB). TB control programmes are facing threats from drug resistance. Multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains need longer and more expensive treatment with many medications resulting in more adverse effects and decreased chances of treatment outcomes. The World Health Organization (WHO) has emphasised the development of not just new individual anti-TB drugs, but also novel medication regimens as an alternative treatment option for the drug-resistant Mtb strains. Many plants, as well as marine creatures (sponge; Haliclona sp.) and fungi, have been continuously used to treat TB in various traditional treatment systems around the world, providing an almost limitless supply of active components. Natural products, in addition to their anti-mycobacterial action, can be used as adjuvant therapy to increase the efficacy of conventional anti-mycobacterial medications, reduce their side effects, and reverse MDR Mtb strain due to Mycobacterium's genetic flexibility and environmental adaptation. Several natural compounds such as quercetin, ursolic acid, berberine, thymoquinone, curcumin, phloretin, and propolis have shown potential anti-mycobacterial efficacy and are still being explored in preclinical and clinical investigations for confirmation of their efficacy and safety as anti-TB medication. However, more high-level randomized clinical trials are desperately required. The current review provides an overview of drug-resistant TB along with the latest anti-TB medications, drug-induced hepatotoxicity and oxidative stress. Further, the role and mechanisms of action of first and second-line anti-TB drugs and new drugs have been highlighted. Finally, the role of natural compounds as anti-TB medication and hepatoprotectants have been described and their mechanisms discussed.

Insect Microbial Symbionts: Ecology, Interactions, and Biological Significance.

The guts of insect pests are typical habitats for microbial colonization and the presence of bacterial species inside the gut confers several potential advantages to the insects. These gut bacteria are located symbiotically inside the digestive tracts of insects and help in food digestion, phytotoxin breakdown, and pesticide detoxification. Different shapes and chemical assets of insect gastrointestinal tracts have a significant impact on the structure and makeup of the microbial population. The number of microbial communities inside the gastrointestinal system differs owing to the varying shape and chemical composition of digestive tracts. Due to their short generation times and rapid evolutionary rates, insect gut bacteria can develop numerous metabolic pathways and can adapt to diverse ecological niches. In addition, despite hindering insecticide management programs, they still have several biotechnological uses, including industrial, clinical, and environmental uses. This review discusses the prevalent bacterial species associated with insect guts, their mode of symbiotic interaction, their role in insecticide resistance, and various other biological significance, along with knowledge gaps and future perspectives. The practical consequences of the gut microbiome and its interaction with the insect host may lead to encountering the mechanisms behind the evolution of pesticide resistance in insects.

Functional traits and phylogenetic analysis of top-soil inhabiting rhizobacteria associated with tea rhizospheres in North Bengal, India.

Rhizobacteria associated with cultivated crops are known to stimulate plant growth through various indirect or direct mechanisms. In recent years, the host list of plant growth promotion/promoting rhizobacteria has expanded to include bean, barley, cotton, maize, rice, vegetables, peanut, rice, wheat, and several plantation crops. However, interaction of rhizobacteria with tea plants of organic and conventional tea gardens is poorly understood. In the present study, rhizobacterial species associated with tea rhizosphere were isolated from 14 tea gardens located in North Bengal, India. In total, 16 rhizobacterial isolates isolated from collected soil samples were assessed for antagonistic and plant growth promotion/promoting activity under laboratory conditions. Molecular characterization based on sequencing of 16S rRNA gene revealed dominance of Bacillus with five species followed by Pseudomonas with two species. Interestingly, only one isolate was affiliated with actinobacteria, i.e., Microbacterium barkeri. Out of 16 isolates, isolates Bacillus subtilis OKAKP01, B. subtilis BNLG01, B. paramycoides BOK01, M. barkeri BPATH02, and Stenotrophomonas maltophilia BSEY01 showed highest growth inhibition against Fusarium solani (68.2 to 72.8%), Pseudopestalotiopsis theae (71.1 to 85.6%), and Exobasidium vexans (67.4 to 78.3%) causing respective Fusarium dieback, gray blight, and blister blight diseases in tea crop. Further, these five isolates also possessed significantly greater antifungal (siderophore producer, protease, chitinase, and cellulase activity) and plant growth promotion/promoting (indole-3-acetic acid production, ACC deaminase, ammonia, and phosphate solubilization) traits over other eleven rhizobacterial isolates. Therefore, these five isolates of rhizobacteria were chosen for their plant growth promotion/promoting activity on tea plants in nursery conditions. Results from nursery experiments revealed that these five rhizobacteria significantly improved growth rates of tea plants compared with the control. Therefore, this study suggests that these rhizobacteria could be used to formulate biopesticides and biofertilizers, which could be applied to sustainable tea cultivation to improve crop health and reduce disease attack.

Stenotrophomonas in diversified cropping systems: friend or foe?

In the current scenario, the use of synthetic fertilizers is at its peak, which is an expensive affair, possesses harmful effects to the environment, negatively affecting soil fertility and beneficial soil microfauna as well as human health. Because of this, the demand for natural, chemical-free, and organic foods is increasing day by day. Therefore, in the present circumstances use of biofertilizers for plant growth-promotion and microbe-based biopesticides against biotic stresses are alternative options to reduce the risk of both synthetic fertilizers and pesticides. The plant growth promoting rhizobacteria (PGPR) and microbial biocontrol agents are ecologically safe and effective. Owning their beneficial properties on plant systems without harming the ecosystem, they are catching the widespread interest of researchers, agriculturists, and industrialists. In this context, the genus Stenotrophomonas is an emerging potential source of both biofertilizer and biopesticide. This genus is particularly known for producing osmoprotective substances which play a key role in cellular functions, i.e., DNA replication, DNA-protein interactions, and cellular metabolism to regulate the osmotic balance, and also acts as effective stabilizers of enzymes. Moreover, few species of this genus are disease causing agents in humans that is why; it has become an emerging field of research in the present scenario. In the past, many studies were conducted on exploring the different applications of Stenotrophomonas in various fields, however, further researches are required to explore the various functions of Stenotrophomonas in plant growth promotion and management of pests and diseases under diverse growth conditions and to demonstrate its interaction with plant and soil systems. The present review discusses various plant growth and biocontrol attributes of the genus Stenotrophomonas in various food crops along with knowledge gaps. Additionally, the potential risks and challenges associated with the use of Stenotrophomonas in agriculture systems have also been discussed along with a call for further research in this area.

Molecular signalling during cross talk between gut brain axis regulation and progression of irritable bowel syndrome: A comprehensive review.

Irritable bowel syndrome (IBS) is a chronic functional disorder which alters gastrointestinal (GI) functions, thus leading to compromised health status. Pathophysiology of IBS is not fully understood, whereas abnormal gut brain axis (GBA) has been identified as a major etiological factor. Recent studies are suggestive for visceral hyper-sensitivity, altered gut motility and dysfunctional autonomous nervous system as the main clinical abnormalities in IBS patients. Bidirectional signalling interactions among these abnormalities are derived through various exogenous and endogenous factors, such as microbiota population and diversity, microbial metabolites, dietary uptake, and psychological abnormalities. Strategic efforts focused to study these interactions including probiotics, antibiotics and fecal transplantations in normal and germ-free animals are clearly suggestive for the pivotal role of gut microbiota in IBS etiology. Additionally, neurotransmitters act as communication tools between enteric microbiota and brain functions, where serotonin (5-hydroxytryptamine) plays a key role in pathophysiology of IBS. It regulates GI motility, pain sense and inflammatory responses particular to mucosal and brain activity. In the absence of a better understanding of various interconnected crosstalks in GBA, more scientific efforts are required in the search of novel and targeted therapies for the management of IBS. In this review, we have summarized the gut microbial composition, interconnected signalling pathways and their regulators, available therapeutics, and the gaps needed to fill for a better management of IBS.

Molecular interaction between plants and Trichoderma species against soil-borne plant pathogens.

Trichoderma spp. (Hypocreales) are used worldwide as a lucrative biocontrol agent. The interactions of Trichoderma spp. with host plants and pathogens at a molecular level are important in understanding the various mechanisms adopted by the fungus to attain a close relationship with their plant host through superior antifungal/antimicrobial activity. When working in synchrony, mycoparasitism, antibiosis, competition, and the induction of a systemic acquired resistance (SAR)-like response are considered key factors in deciding the biocontrol potential of Trichoderma. Sucrose-rich root exudates of the host plant attract Trichoderma. The soluble secretome of Trichoderma plays a significant role in attachment to and penetration and colonization of plant roots, as well as modulating the mycoparasitic and antibiosis activity of Trichoderma. This review aims to gather information on how Trichoderma interacts with host plants and its role as a biocontrol agent of soil-borne phytopathogens, and to give a comprehensive account of the diverse molecular aspects of this interaction.

Modulatory effect of caffeic acid in alleviating diabetes and associated complications.

Diabetes mellitus (DM) is one of the most common metabolic disorders characterized by elevated blood glucose levels. Prolonged uncontrolled hyperglycemia often leads to multi-organ damage including diabetic neuropathy, nephropathy, retinopathy, cardiovascular disorders, and diabetic foot ulcers. Excess production of free radicals causing oxidative stress in tissues is often considered to be the primary cause of onset and progression of DM and associated complications. Natural polyphenols can be used to induce or inhibit the expression of antioxidant enzymes such as glutathione peroxidase, heme oxygenase-1, superoxide dismutase, and catalase that are essential in maintaining redox balance, and ameliorate oxidative stress. Caffeic acid (CA) is a polyphenolderived from hydroxycinnamic acid and possesses numerous physiological properties includ-ing antioxidant, anti-inflammatory, anti-atherosclerotic, immune-stimulatory, cardioprotective, antiproliferative, and hepatoprotective activities. CA acts as a regulatory compound affecting numerous biochemical pathways and multiple targets. These include various transcription factors such as nuclear factor-B, tumor necrosis factor-α, interleukin-6, cyclooxygenase-2, and nuclear factor erythroid 2-related factor 2. Therefore, this review summarizes the pharmacological properties, molecular mechanisms, and pharmacokinetic profile of CA in mitigating the adverse effects of DM and associated complications. The bioavailability, drug delivery, and clinical trials of CA have also been discussed.

Current therapeutic modalities and chemopreventive role of natural products in liver cancer: Progress and promise.

Liver cancer is a severe concern for public health officials since the clinical cases are increasing each year, with an estimated 5-year survival rate of 30%-35% after diagnosis. Hepatocellular carcinoma (HCC) constitutes a significant subtype of liver cancer (approximate75%) and is considered primary liver cancer. Treatment for liver cancer mainly depends on the stage of its progression, where surgery including, hepatectomy and liver transplantation, and ablation and radiotherapy are the prime choice. For advanced liver cancer, various drugs and immunotherapy are used as first-line treatment, whereas second-line treatment includes chemotherapeutic drugs from natural and synthetic origins. Sorafenib and lenvatinib are first-line therapies, while regorafenib and ramucirumab are second-line therapy. Various metabolic and signaling pathways such as Notch, JAK/ STAT, Hippo, TGF-ß, and Wnt have played a critical role during HCC progression. Dysbiosis has also been implicated in liver cancer. Drug-induced toxicity is a key obstacle in the treatment of liver cancer, necessitating the development of effective and safe medications, with natural compounds such as resveratrol, curcumin, diallyl sulfide, and others emerging as promising anticancer agents. This review highlights the current status of liver cancer research, signaling pathways, therapeutic targets, current treatment strategies and the chemopreventive role of various natural products in managing liver cancer.

Grey Blight Disease Detection on Tea Leaves Using Improved Deep Convolutional Neural Network.

We proposed a novel deep convolutional neural network (DCNN) using inverted residuals and linear bottleneck layers for diagnosing grey blight disease on tea leaves. The proposed DCNN consists of three bottleneck blocks, two pairs of convolutional (Conv) layers, and three dense layers. The bottleneck blocks contain depthwise, standard, and linear convolution layers. A single-lens reflex digital image camera was used to collect 1320 images of tea leaves from the North Bengal region of India for preparing the tea grey blight disease dataset. The nongrey blight diseased tea leaf images in the dataset were categorized into two subclasses, such as healthy and other diseased leaves. Image transformation techniques such as principal component analysis (PCA) color, random rotations, random shifts, random flips, resizing, and rescaling were used to generate augmented images of tea leaves. The augmentation techniques enhanced the dataset size from 1320 images to 5280 images. The proposed DCNN model was trained and validated on 5016 images of healthy, grey blight infected, and other diseased tea leaves. The classification performance of the proposed and existing state-of-the-art techniques were tested using 264 tea leaf images. Classification accuracy, precision, recall, F measure, and misclassification rates of the proposed DCNN are 98.99%, 98.51%, 98.48%, 98.49%, and 1.01%, respectively, on test data. The test results show that the proposed DCNN model performed superior to the existing techniques for tea grey blight disease detection.

Mycotoxins along the tea supply chain: A dark side of an ancient and high valued aromatic beverage.

ABSTRACTSTea (Camellia sinensis L.) is a high valued beverage worldwide since ancient times; more than three billion cups of tea are consumed each day. Leaf extracts of the plant are used for food preservation, cosmetics, and medicinal purposes. Nevertheless, tea contaminated with mycotoxins poses a serious health threat to humans. Mycotoxin production by tea fungi is induced by a variety of factors, including poor processing methods and environmental factors such as high temperature and humidity. This review summarizes the studies published to date on mycotoxin prevalence, toxicity, the effects of climate change on mycotoxin production, and the methods used to detect and decontaminate tea mycotoxins. While many investigations in this domain have been carried out on the prevalence of aflatoxins and ochratoxins in black, green, pu-erh, and herbal teas, much less information is available on zearalenone, fumonisins, and Alternaria toxins. Mycotoxins in teas were detected using several methods; the most commonly used being the High-Performance Liquid Chromatography (HPLC) with fluorescence detection, followed by HPLC with tandem mass spectrometry, gas chromatography and enzyme-linked immunosorbent assay. Further, mycotoxins decontamination methods for teas included physical, chemical, and biological methods, with physical methods being most prevalent. Finally, research gaps and future directions have also been discussed.

Recent advances in delivering free or nanoencapsulated Curcuma by-products as antimicrobial food additives.

Food commodities are often contaminated by microbial pathogens in transit or during storage. Hence, mitigation of these pathogens is necessary to ensure the safety of food commodities. Globally, researchers used botanicals as natural additives to preserve food commodities from bio-deterioration, and advances were made to meet users' acceptance in this domain, as synthetic preservatives are associated with harmful effects to both consumers and environments. Over the last century, the genus Curcuma has been used in traditional medicine, and its crude and nanoencapsulated essential oils (EOs) and curcuminoids were used to combat harmful pathogens that deteriorate stored foods. Today, more research is needed for solving the problem of pathogen resistance in food commodities and to meet consumer demands. Therefore, Curcuma-based botanicals may provide a source of natural preservatives for food commodities that satisfy the needs both of the food industry and the consumers. Hence, this article discusses the antimicrobial and antioxidant properties of EOs and curcuminoids derived from the genus Curcuma. Further, the action modes of Curcuma-based botanicals are explained, and the latest advances in nanoencapsulation of these compounds in food systems are discussed alongside knowledge gaps and safety assessment where the focus of future research should be placed.

Trichoderma reesei as an elicitor triggers defense responses in tea plant and delays gray blight symptoms.

Gray blight caused by Pestalotiopsis-like species is a major disease of tea crop worldwide including India, causes significant losses in tea production. Management of disease using fungal biocontrol agents is considered an alternative eco-friendly approach to synthetic fungicides. The present study explores the efficacy of Trichoderma reesei in the gray blight management in tea crop and activation of defense related enzymes against gray blight pathogen by developing a tri-trophic interaction system. Out of 16 isolates of Trichoderma species screened in laboratory against Pseudopestalotiopsis theae, a gray blight pathogen, isolate TRPATH01 had highest antagonistic activity (81.2%) against Ps. theae and was found to produce inhibitory volatile and non-volatile metabolites. Based on ITS and TEF-1 alpha sequencing, the isolate TRPATH01 was recognised as T. reesei. The methanolic extract of T. reesei was also found effective against Ps. theae at 200 µg/mL also confirmed presence of highest volatile compounds. The isolate also produced hydrolytic enzymes such as chitinase, cellulase, protease, and lipase. Under nursery conditions, 2% and 5% concentrations with 2 × 106 conidia/ml of T. reesei were able to reduce 67.5% to 75.0% of disease severity over pathogen inoculated controls. Moreover, compared with positive and negative controls, T. reesei -treated tea plants showed increased shoot height, stem diameter, shoot and root fresh weight at 45 days after inoculation. Principal component analysis capturing 97.1% phenotypic variations, which revealed that the tea plants co-inoculated with Ps. theae and T. reesei exhibited significantly upregulated accumulation of defensive enzymes viz., polyphenol oxidase, peroxidase, phenylalanine ammonia lyase, phenolics, ß-1, 3-glucanase, and chitinase when compared to both controls. Hence, T. reesei could provide an eco-friendly and viable mitigation option for gray blight in tea gardens by inducing defense-related enzymes.

Characterization and identification of fungicide insensitive Pestalotiopsis-like species pathogenic to tea crop in India.

Gray blight, a fungal disease caused by Pestalotiopsis-like species, is a widespread disease affecting tea crop (Camellia sinensis (L.) Kuntze) in many tea-growing countries, including India, resulting in huge losses in tea production. In India, several studies have been conducted to understand the fungal diseases of tea crop, but gray blight has not been well described in major tea growing areas such as in North Bengal, based on its geographic distribution, molecular analysis, or pathogenicity, and even fungicide resistance. The objective of this study was to identify and characterize the causative agents of gray blight disease in symptomatic leaf sample of tea crop collected from 27 tea gardens located in North Bengal, India and to evaluate some common fungicides against them in order to understand the resistance mechanism. In this study, we characterized Pestalotiopsis-like species based on the phylogenies of DNA sequences (internal transcribed spacers) and assessment of conidial characteristics. The study revealed that out of 27 isolates of gray blight pathogens, 17 belonged to the genus Pseudopestalotiopsis (Ps.), six isolates were Neopestalotiopsis, and four were Pestalotiopsis. Two novel species, Ps. thailandica and N. natalensis were introduced through this study. The most frequently isolated genus from C. chinensis was Pseudopestalotiopsis. Pathogenicity tests showed that the isolates displayed significantly different virulence when inoculated onto wounded tea leaves and the mycelial growth rate was positively correlated with pathogenicity (P < 0.01). Based on the 13 ISSR (Inter Simple Sequence Repeat) markers used and principal coordinate analysis, it was found that isolates were very diverse. Out of 27 isolates, IND0P2, DLG0P10, and BHAT0P11 isolates were insensitive against both MBC + M3 (Carbendazim + Mancozeb) and DMI (Hexaconazole) fungicides, while isolates SANY0P18, PAHG0P19, RANG0P24, and SING0P25 were insensitive only against MBC + M3 fungicide. Further, these insensitive isolates were grouped into separate clusters by ISSR, indicating their distinctiveness. However, all the evaluated isolates were susceptible to M1 (copper oxychloride) and another DMI (propiconazole) fungicides. Therefore, to manage gray blight, fungicide resistance management strategies as recommended by Fungicide Resistance Action Committee should be implemented.

Role of baicalin as a potential therapeutic agent in hepatobiliary and gastrointestinal disorders: A review.

Baicalin is a natural bioactive compound derived from Scutellaria baicalensis, which is extensively used in traditional Chinese medicine. A literature survey demonstrated the broad spectrum of health benefits of baicalin such as antioxidant, anticancer, anti-inflammatory, antimicrobial, cardio-protective, hepatoprotective, renal protective, and neuroprotective properties. Baicalin is hydrolyzed to its metabolite baicalein by the action of gut microbiota, which is further reconverted to baicalin via phase 2 metabolism in the liver. Many studies have suggested that baicalin exhibits therapeutic potential against several types of hepatic disorders including hepatic fibrosis, xenobiotic-induced liver injury, fatty liver disease, viral hepatitis, cholestasis, ulcerative colitis, hepatocellular and colorectal cancer. During in vitro and in vivo examinations, it has been observed that baicalin showed a protective role against liver and gut-associated abnormalities by modifying several signaling pathways such as nuclear factor-kappa B, transforming growth factor beta 1/SMAD3, sirtuin 1, p38/mitogen-activated protein kinase/Janus kinase, and calcium/calmodulin-dependent protein kinase kinaseß/adenosine monophosphate-activated protein kinase/acetyl-coenzyme A carboxylase pathways. Furthermore, baicalin also regulates the expression of fibrotic genes such as smooth muscle actin, connective tissue growth factor, ß-catenin, and inflammatory cytokines such as interferon gamma, interleukin-6 (IL-6), tumor necrosis factor-alpha, and IL-1ß, and attenuates the production of apoptotic proteins such as caspase-3, caspase-9 and B-cell lymphoma 2. However, due to its low solubility and poor bioavailability, widespread therapeutic applications of baicalin still remain a challenge. This review summarized the hepatic and gastrointestinal protective attributes of baicalin with an emphasis on the molecular mechanisms that regulate the interaction of baicalin with the gut microbiota.

Onion anthocyanins: Extraction, stability, bioavailability, dietary effect, and health implications.

Anthocyanins are high-value compounds, and their use as functional foods and their natural colorant have potential health benefits. Anthocyanins seem to possess antioxidant properties, which help prevent neuronal diseases and thereby exhibit anti-inflammatory, chemotherapeutic, cardioprotective, hepatoprotective, and neuroprotective activities. They also show different therapeutic effects against various chronic diseases. Anthocyanins are present in high concentrations in onion. In recent years, although both conventional and improved methods have been used for extraction of anthocyanins, nowadays, improved methods are of great importance because of their higher yield and stability of anthocyanins. In this review, we compile anthocyanins and their derivatives found in onion and the factors affecting their stability. We also analyze different extraction techniques of anthocyanins. From this point of view, it is very important to be precisely aware of the impact that each parameter has on the stability and subsequently potentiate its bioavailability or beneficial health effects. We present up-to-date information on bioavailability, dietary effects, and health implications of anthocyanins such as antioxidant, antidiabetic, anticancerous, antiobesity, cardioprotective, and hepatoprotective activities.