Early Detection of Fusarium Basal Rot Infection in Onions and Shallots Based on VOC Profiles Analysis.

Gas chromatography ion-mobility spectrometry (GC-IMS) technology is drawing increasing attention due to its high sensitivity, low drift, and capability for the identification of compounds. The noninvasive detection of plant pests and pathogens is an application area well suited to this technology. In this work, we employed GC-IMS technology for early detection of Fusarium basal rot in brown onion, red onion, and shallot bulbs and for tracking disease progression during storage. The volatile profiles of the infected and healthy control bulbs were characterized using GC-IMS and gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS). GC-IMS data combined with principal component analysis and supervised methods provided discrimination between infected and healthy control bulbs as early as 1 day after incubation with the pathogen, classification regarding the proportion of infected to healthy bulbs in a sample, and prediction of the infection's duration with an average R2 = 0.92. Furthermore, GC-TOF-MS revealed several compounds, mostly sulfides and disulfides, that could be uniquely related to Fusarium basal rot infection.

Development of effluent-free dry-peeling method for shallots (Allium cepa L. aggregatum): Spectral characterization of mid and long infrared peak wavelengths for maximizing the peeling performance.

Different wavelength emitting infrared (IR) lamps (transparent quartz tungsten (TQT), ruby-coated quartz tungsten (RCQT), and ceramic) were used for dry peeling and evaluating the spectral characteristics of emitted radiations. The maximum temperatures for ceramic, RCQT, and TQT were 560, 662, and 861°C, respectively. The peak wavelength determined by Wien's law was between 3.37 and 21.47 µm. Comparatively, longer wavelength was emitted by ceramic lamp. The spectral emissive power determined by Stefan Boltzmann's law was 1.14-37.49 kW m-2 using the IR emitters at different power levels. The radiant efficiency was higher for the ceramic lamp. The peak wavelength and emissive power had a major influence on the peeling performance and quality during IR peeling. The optimized parameters for IR dry peeling of shallots are 60 mm distance between lamp and product, 59.74% IR power level, 15 min of heating time using the ceramic (peak wavelength 8.16 µm) lamp. Practical Application: Infrared dry peeling of shallots is a sustainable alternative to traditional peeling methods that leaves adverse environmental footprints. Spectral characteristics of the infrared lamp can be used to determine the suitable emitter for the dry-peeling operation. It is necessary to check the wavelength emitted by the source for designing the IR system based on the food product and application. This study will be helpful in food processing industries to use an effective infrared lamp that can efficiently peel the agricultural product and sustainably maintain quality.

Quercetin extraction from small onion skin (Allium cepa L. var. aggregatum Don.) and its antioxidant activity.

In the present study, the maximum yield of quercetin was optimized for the ethanol extraction of small onions (Allium cepa L. var. aggregatum Don.), and the antioxidant activity was investigated in vitro. The extraction of quercetin from the small onion skin was carried out through ethanol solvent extraction with different ratios of ethanol and water. Ethanol: water ratio produced the highest quercetin from the onion skin. RP-HPLC analysis of the extracted material showed 2, 122 mg/g of quercetin and 0.34 mg/g of isorhamnetin. A total of 301.03 mg GAE/g dry weight and 156 mg/g quercetin equivalents were found in the onion skin extract. DPPH and ABTS free radical scavenging potentials of the tested extract (90:10 v/v) were dose-dependent, with IC50 values of 62.27 µg/mL and 53.65 µg/mL, respectively. Therefore, the present study reports that small onion skin extract rich in quercetin may serve as a promising antioxidant and anticancer agent.

Screening of Anti-carcinogenic Properties of Phytocompounds from Allium ascalonicum for Treating Breast Cancer Through In Silico and In Vitro Approaches.

Plants, rich in phytocompounds, have been in usage since time immemorial for treating various diseases, namely, cancer. One such plant species, Allium ascalonicum (Shallot) belonging to Amaryllidaceae family is being studied here for its anti-carcinogenic properties against breast cancer. GC-MS characterization of A. ascalonicum exhibited 48 phytocompounds containing five peak phytocompounds and 13 phytocompounds with anti-carcinogenic properties. These 13 anti-carcinogenic phytocompounds were docked with three hormonal receptors involved in breast cancer malignancy, namely, ERα, PR, and human EGFR with tamoxifen as standard for in silico analysis. The results exhibited three phytocompounds that had better binding scores compared to that of the standard drug, tamoxifen. Lyophilized powder of aqueous A. ascalonicum extract, also referred as ASE, was used for in vitro approaches. Antioxidant study using DPPH assay revealed that the highest percentage of FRSA in ASE, nearly 51%, was observed at 50 µg/ml concentration. Cytotoxicity study on MCF-7 cell line using MTT assay demonstrated IC50 value at 1400 µg/ml and anti-proliferative study using Trypan blue assay for the determination of percentage viability of MCF-7 cells at IC50 concentration was observed to be 49%. Anti-mitotic activity using Vigna radiata seed germination assay revealed clear morphological differences in a dose-dependent manner between the seeds grown at various concentrations of ASE with nearly 56.5% growth inhibition observed at 1500 µg/ml concentration. Hence, this research work proves that Allium ascalonicum has very good anti-carcinogenic properties and this can be confirmed further through in vivo animal model studies and it can also be formulated as a promising drug to treat breast cancer. GC-MS characterization of Allium ascalonicum demonstrated the presence of five peak compounds and thirteen anti-carcinogenic compounds. The thirteen anti-carcinogenic compounds were docked with three target proteins (in silico analysis) involved in breast cancer malignancy and identified the presence of three potential phytocompounds that can be used for treating breast cancer. In vitro approaches also confirmed the presence of anti-carcinogenic properties such as antioxidative potential, cytotoxic, anti-proliferative, and anti-mitotic effects. Hence, Allium ascalonicum can be taken further to in vivo studies so that it can be formulated to treat breast cancer.

Preliminary Studies on Detection of Fusarium Basal Rot Infection in Onions and Shallots Using Electronic Nose.

The evaluation of crop health status and early disease detection are critical for implementing a fast response to a pathogen attack, managing crop infection, and minimizing the risk of disease spreading. Fusarium oxysporum f. sp. cepae, which causes fusarium basal rot disease, is considered one of the most harmful pathogens of onion and accounts for considerable crop losses annually. In this work, the capability of the PEN 3 electronic nose system to detect onion and shallot bulbs infected with F. oxysporum f. sp. cepae, to track the progression of fungal infection, and to discriminate between the varying proportions of infected onion bulbs was evaluated. To the best of our knowledge, this is a first report on successful application of an electronic nose to detect fungal infections in post-harvest onion and shallot bulbs. Sensor array responses combined with PCA provided a clear discrimination between non-infected and infected onion and shallot bulbs as well as differentiation between samples with varying proportions of infected bulbs. Classification models based on LDA, SVM, and k-NN algorithms successfully differentiate among various rates of infected bulbs in the samples with accuracy up to 96.9%. Therefore, the electronic nose was proved to be a potentially useful tool for rapid, non-destructive monitoring of the post-harvest crops.

Study on the characteristics of gluten/alginate-cellulose/onion waste extracts composite film and its food packaging application.

The study aimed to improve the properties of SA-CMC film by gluten (G) blends and bioactive compounds from onion waste extracts (OWEs) peel (OPE) and stalk (OSE). The applicability of film on the quality of peeled shallot onion during storage was also examined. Water barrier (0.62 g/msPa × 10-14) and tensile strength (11.50 MPa) of G/SA-CMC film improved more than SA-CMC film (1.55 g/msPa × 10-13 and 7.05 MPa). OPE and OSE increase the total phenolic content (43.86 and 38.35 mgGAE/g) and radical scavenging activity (88.74 and 68.30 %) of G/SA-CMC film than control (20.33 mgGAE/g and 39.20 %). Microbial load (logCFU/g) in terms of total bacterial count, yeast and mold count of shallot onion packed in OPE (5.34 and 5.21) and OSE (4.26 and 4.21) film was reduced than control (6.03 and 4.68). Thus, the G/SA-CMC/OWEs film had improved properties than SA-CMC film and can be used to store peeled onion at 4℃ for 21 days.

Antiallergic activities of shallot (Allium ascalonicum L.) and its therapeutic effects in allergic rhinitis.

BACKGROUND: Onion has antiallergic activity but lack of evidence for shallot. OBJECTIVE: To determine whether shallot owns similar antiallergic activity to onion and its therapeutic effects in allergic rhinitis when added to standard treatment. METHODS: In-vitro ß-hexosaminidase inhibitory activities of shallot was compared with onion on RBL-2H3 cells. In clinical study, a randomized, double-blind, placebo-controlled trial was performed. Sixteen AR patients were randomized equally into the controls who received cetirizine 10 mg once daily and placebo capsules for 4 weeks, and the treatment who received 3g of oral shallot per day (equivalent to 1 ½ bulbs) and cetirizine. Visual analog scores of overall symptoms (VAS), total nasal and ocular symptom scores (TNSS and TOSS), nasal airway resistance (NAR), and adverse events were assessed. RESULTS: Shallot extract at 200 µg/mL had an average ß-hexosaminidase inhibition rate of 97% while onion extract had 73%. HPLC chromatograms (λ = 290nm) of both plants showed nearly identical patterns of quercetin compounds, such as quercetin 3,4'-diglucoside, quercetin 4'-glucoside, and quercetin. After 4-week of treatment, 62.5% of patients in shallot group and 37.5% of patients in control group showed improvement of post-treatment VAS. TNSS were significantly reduced in both groups, however no difference between groups (P = 0.18). TOSS were significantly improved only in the shallot group (P = 0.01). Adverse events from shallot were not different from placebo. CONCLUSIONS: Shallot had antiallergic activity and similar quercetin compounds to onion. The shallot oral supplement and cetirizine was shown to improve the overall AR symptoms more than cetirizine alone.

Antibacterial and antioxidant potential of the phenolic extract and its fractions isolated from Allium ascalonicum (onion) peel.

Aqueous methanolic (20:80) crude extract of the outer peel of Allium ascalonicum (onions) was fractionated into anthocyanin (II), acidic (i.e., phenolic acids, Ia), neutral A (i.e., flavanols, Ib) and neutral B (i.e., flavonols, Ic) phenols using C-18 and hydrophilic-lipophilic balanced (HLB) Co-polymer cartridges. The fractions were analysed for total phenolic, total flavonoids, antibacterial activity, antioxidant potential and lipoxygenase (LOX) inhibition. The recovery of total phenols and bio functional activity in all fractions were found to be more in HLB. All fractions showed antimicrobial activity against tested strains with phenolic acids (Ia) being most active and flavanol (Ib) least active, while the highest free radical scavenging, reducing power and LOX inhibition was exhibited by flavonol (Ic) and least by flavanols (Ib). HPLC analysis revealed the presence of vanillic acid and quercetin in non-anthocyanin I and cyanidin in anthocyanin II.

Shallot skin profilling, computational evaluation of physicochemical properties, ADMET, and molecular docking of its components against P2Y12 receptor.

OBJECTIVES: Medicinal plants are a source of many compounds that are useful in the pharmaceutical field for novel drug development. Polyphenols and the flavonoid group in plants are known to have several activities, such as relieving cardio vascular disease (CVD). The outer skin of the shallot which is disposed of as waste is known to have an antiplatelet activity which was tested in vitro assay. To date, there is no study reported on the ADMET profile and physicochemical properties of the active component of the shallot skins. METHODS: The extraction of shallot skins was conducted by ultrasonic irradiation using ethanol. The phytochemical screenings were carried out by TLC and color reaction. The profiling of its active ingredient was presented by GC-MS, HPLC and spectrophotometry UV-vis. Whereas their physicochemical properties were analyzed by ChemDraw 17.00 program and the ADMET predictions were studied using pkCSM online tool. The MVD program was operated in the docking study on protein P2Y12 (PDB ID 4PXZ). RESULTS: The extract showed the presence of polyphenol, flavonoids, quercetin, natalensine-3,5-dinitrobenzoate; bis[2-(2-fluorophenyl)-6-fluoroquinolin-4-yl]amine, benzo[a]heptalene, N-(trifluoroacetyl) methyl-N-deacethyl-colchicine. The ADMET prediction data displayed that the compounds in the extract have good absorption so that they can be used in the oral and transdermal routes. Some components in the extract have lower MDS than clopidogrel. CONCLUSIONS: The ultrasonicated shallot skin extract can be used as additional resources of the active pharmaceutical ingredients and to have the potency to be developed as an oral or transdermal preparation.

Cryopreservation of Plant Shoot Tips of Potato, Mint, Garlic, and Shallot Using Plant Vitrification Solution 3.

Cryopreservation of shoot tips facilitates long-term storage of plant genetic resources which can otherwise only be propagated vegetatively. The vitrification approach using the cryoprotectant plant vitrification solution 3 (PVS3, 50% sucrose and 50% glycerol) is easy to handle, has shown to produce high regrowth percentages in a number of potato, mint, garlic, and shallot accessions, and is, thus, highly suitable for routine cryopreservation of plant genetic resources. In the current chapter, the vitrification procedure is described for potato, mint, garlic, and shallot and includes details about modifications for the different plant species. Special emphasis is given on the preparation of the different culture media, solutions, the culture conditions prior and post-cryopreservation, and the preparation of the shoot tips from different sources. Furthermore, protocols to introduce plants into in vitro culture and methods to estimate cryopreservation success are provided.

Analysis of volatile compound changes in fried shallot (Allium cepa L. var. aggregatum) oil at different frying temperatures by GC-MS, OAV, and multivariate analysis.

Flavor is a key attribute of fried oil that shows a critical correlation with temperature. Therefore, selecting the appropriate temperature is important in preparing fried shallot oil (FSO). Volatile compounds from five different FSOs were identified and comparatively studied using gas chromatography-mass spectrometry (GC-MS) coupled with multivariate data analysis, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). GC-MS results identified a total of 93 volatiles, among which aldehydes, alcohols, pyrazines, and sulfur-containing compounds were the major compounds. Eighteen compounds had odor active values (OAV) >1. Among the compounds, hexanal, (E)-2-heptenal, (E)-2-octenal, dipropyl disulfide, 2-ethyl-3,5-dimethylpyrazine, and 1-octen-3-ol were important to the overall aroma profile of FSOs. In the PCA model, all the detected FSOs were divided into three clusters, which were assigned as cluster A (FSO5), B (FSO4), and C (the rest FSOs). Multivariate data analyses revealed that nonanal, 2-ethyl-5-methylpyrazine, (E,E)-2,4-decadienal, (E)-2-heptenal, and hexanal contributed positively to the classification of different FSOs. GC-MS coupled with multivariate data analysis could be used as a convenient and efficient analytical method to classify raw materials.

Integration of Nitrogen and Biofertilizer on the Agronomic Efficiency and Quality of Shallot (Allium ascalonicum L.) Plant in the Rainy Season.

BACKGROUND AND OBJECTIVE: In the rainy season farmers don't interest to cultivate shallot because in addition to providing a high dosage of fertilizer they are also sensitive to pathogenic attacks so they are afraid of crop failure and cause low shallot production. This study aimed to knew effect of agronomic component and quality of shallot under different concentrations of biofertilizer and Ammonium Sulphate (AS) fertilizer dose in the rainy season. MATERIALS AND METHODS: The study was conducted in Cangkring, Srandakan, Bantul, Special Region of Yogyakarta Indonesia from August to October 2019. The study was arranged in RCBD factorial with three replications. The first factor was a various dose of ammonium sulphate (100, 200 and 300 kg ha-1). The second factor was various concentrations of biofertilizer (2, 3 and 4%), and control. The observed variables were the analysis of growth yield and quality component of shallot plant. The analyzed using analysis of variance at 5% of significance then continued by DMRT at 5% of significance. RESULTS: There was the interaction between the application of AS dosage and biofertilizer concentration on all of variable observations. There was a significant difference between treatment with control on all of the observation variables. CONCLUSION: The combination of AS fertilizer 200 kg ha-1 dose and 3% biofertilizer concentration increased agronomic efficiency, growth, bulbs yields, and quality of bulbs include provitamin A, oleoresin compounds.

Metabolome-Based Discrimination Analysis of Shallot Landraces and Bulb Onion Cultivars Associated with Differences in the Amino Acid and Flavonoid Profiles.

Shallot landraces and varieties are considered an important genetic resource for Allium breeding due to their high contents of several functional metabolites. Aiming to provide new genetic materials for the development of a novel bulb onion cultivar derived from intraspecific hybrids with useful agronomic traits from shallots, the metabolic profiles in the bulbs of 8 Indonesian shallot landraces and 7 short-day and 3 long-day bulb onion cultivars were established using LC-Q-TOF-MS/MS. Principal component analysis, partial least squares discriminant analysis, and dendrogram clustering analysis showed two major groups; group I contained all shallot landraces and group II contained all bulb onion cultivars, indicating that shallots exhibited a distinct metabolic profile in comparison with bulb onions. Variable importance in the projection and Spearman's rank correlation indicated that free and conjugated amino acids, flavonoids (especially metabolites having flavonol aglycone), and anthocyanins, as well as organic acids, were among the top metabolite variables that were highly associated with shallot landraces. The absolute quantification of 21 amino acids using conventional HPLC analysis showed high contents in shallots rather than in bulb onions. The present study indicated that shallots reprogrammed their metabolism toward a high accumulation of amino acids and flavonoids as an adaptive mechanism in extremely hot tropical environments.

Effect of Extraction Methods on Antioxidant Activity of Papery Skin Extracts and Fractions of Maja Cipanas Onion (Allium cepa L. var. ascalonicum).

Extraction can be carried out at ambient temperature or high temperature to accelerate the extraction process of secondary metabolites from simplicia. This study aimed to determine the effectiveness of extraction methods on antioxidant activity of secondary metabolites of papery skin extracts and fractions of Maja Cipanas onion (Allium cepa L. var. ascalonicum). Extraction methods were maceration, percolation, reflux, and Soxhlet method, and then, concentrated extracts were fractionated by liquid-liquid extraction based on the polarity of secondary metabolites. Antioxidant activity was determined by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The phytochemical screening showed that onion papery skin contained alkaloids, polyphenols, flavonoids, and tannins. The IC50 value of the extract, ethyl acetate fraction, and water fraction of the four extraction methods in the concentration range 25-400 µg/mL were in the range of 55.62-107.08, 31.31-84.06, and 126.05-139.82 µg/mL, respectively, while the IAA value was in the ranges of 0.25-0.49, 0.32-0.86, and 0.19-0.21, respectively. Variation in IC50 and IAA values indicate that the extraction method affects antioxidant activity, due to extracted secondary metabolites from simplicia. The highest antioxidant activity was an ethyl acetate fraction by the reflux method, while the lowest was water fraction by the percolation method.

Isolation and characterization of Cepa2, a natural alliospiroside A, from shallot (Allium cepa L. Aggregatum group) with anticancer activity.

Exploration of new and promising anticancer compounds continues to be one of the main tasks of cancer research because of the drug resistance, high cytotoxicity and limitations of tumor selectivity. Natural products represent a better choice for cancer treatment in comparison with synthetic compounds because of their pharmacokinetic properties and lower side effects. In the current study, we isolated a steroidal saponin, named Cepa2, from the dry roots of shallot (Allium cepa L. Aggregatum group), and determined its structure by using two-dimensional nuclear manganic resonance (2D NMR). The 1H NMR and 13C NMR data revealed that the newly isolated Cepa2 compound is identical to alliospiroside A (C38H60O12) [(25S)-3ß-hydroxyspirost-5-en-1ß-yl-2-O-(6-deoxy-α-L-mannopyranosyl)-α-L-arabinopyranoside], whose anticancer activity remains elusive. Our in vitro examination of the cytotoxic activity of the identified Cepa2 against P3U1 myeloma cancer cell line showed its high efficiency as an anticancer with 91.13% reduction in P3U1 cell viability 12 h post-treatment. The reduction of cell viability was correlated with the increase in reactive oxygen species levels in Cepa2-treated P3U1 cells, as compared with untreated cells. Moreover, scanning electron microscope results demonstrated apoptosis of the Cepa2-treated P3U1 cells in a time course-dependent manner. The results of our study provide evidence for the anticancer properties of the natural Cepa2/alliospiroside A extracted from shallot plants, and a strong foundation for in-depth investigations to build theoretical bases for cell apoptosis and development of novel anticancer drugs.

TLC determination of flavonoids from different cultivars of Allium cepa and Allium ascalonicum.

This study comprises the optimization and validation of a new TLC method for determination of flavonols in the bulbs of seven cultivars of onions and shallots. Separation was performed on RP-18 plates with the solvent mixture tetrahydrofuran/water/formic acid (40+60+6, V/V/V) as a mobile phase. The method was evaluated for precision, linearity, LOD, LOQ, accuracy and robustness. Chromatographic analysis of the extracts revealed the presence of three main flavonols, quercetin, quercetin-4'-O-glucoside and quercetin-3,4'-O-diglucoside in the majority of analyzed cultivars. The content of flavonols in the analyzed extracts of onion bulbs varied from 123 ('Exihibition') to 1079 mg kg-1 fresh mass (fm) ('Hybing') in edible parts, and from 1727 ('Hyline') to 28949 mg kg-1 fm ('Red Baron') in outer scales. The bulbs of two shallot cultivars contained 209 ('Ambition') and 523 mg kg-1 fm ('Matador') of flavonols in edible parts and 5426 and 8916 mg kg-1 fm in outer scales, respectively.

An investigation of antimicrobial and wound healing potential of Allium ascalonicum Linn.

BACKGROUND: The pharmacological properties of Allium ascalonicum Linn., commonly called shallot, have been reported as including those that are antibacterial and antioxidant. OBJECTIVE: The present study aimed to evaluate the antimicrobial effect and wound-healing activity ofthe ethanolic extracts of Allium ascalonicum Linn. (AAE). MATERIAL AND METHOD: The antimicrobial activity of AAE was tested in vitro against using the disc diffusion method and a broth micro-dilution technique to determine the minimal inhibition concentrations (MIC) and the minimal microbicidal concentrations (MMC). Wound-healing activity of the extract was performed on rat test subjects. RESULTS: The AAE showed potential antimicrobial activity by inhibiting gram-positive bacteria Staphylococcus epidermidis and Bacillus subtilis ATCC 6633. MIC and MMC varied from 25-50 mg/ml and 25-200 mg/ml, respectively. After surgery 14 days, wound contractions oftreated groups and standard group were 78.61 +/- 1.20%, 78.55 +/- 1.93% and 100%, respectively; but, in the control group, wound contraction was 64.90 +/- 3.55%. Histological studies showed the complete epidermis and found the collagen fibers and fibroblasts as similar appearance as standard group in dermis. The results of histological evaluation have confirmed remarkable wound-healing activities of AAE. CONCLUSION: Taken together the present study provides evidence that AAE extract processes antimicrobial and wound-healing activities.

Screening and incorporation of rust resistance from Allium cepa into bunching onion (Allium fistulosum) via alien chromosome addition.

Bunching onion (Allium fistulosum L.; 2n = 16), bulb onion (Allium cepa L. Common onion group), and shallot (Allium cepa L. Aggregatum group) cultivars were inoculated with rust fungus, Puccinia allii, isolated from bunching onion. Bulb onions and shallots are highly resistant to rust, suggesting they would serve as useful resources for breeding rust resistant bunching onions. To identify the A. cepa chromosome(s) related to rust resistance, a complete set of eight A. fistulosum - shallot monosomic alien addition lines (MAALs) were inoculated with P. allii. At the seedling stage, FF+1A showed a high level of resistance in controlled-environment experiments, suggesting that the genes related to rust resistance could be located on shallot chromosome 1A. While MAAL, multi-chromosome addition line, and hypoallotriploid adult plants did not exhibit strong resistance to rust. In contrast to the high resistance of shallot, the addition line FF+1A+5A showed reproducibly high levels of rust resistance.

Combined use of high-resolution α-glucosidase inhibition profiling and high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy for investigation of antidiabetic principles in crude plant extracts.

Type 2 diabetes is a metabolic disorder affecting millions of people worldwide, and new drug leads or functional foods containing selective α-glucosidase inhibitors are needed. Crude extract of 24 plants were assessed for α-glucosidase inhibitory activity. Methanol extracts of Cinnamomum zeylanicum bark, Rheum rhabarbarum peel, and Rheum palmatum root and ethyl acetate extracts of C. zeylanicum bark, Allium ascalonicum peel, and R. palmatum root showed IC50 values below 20 µg/mL. Subsequently, high-resolution α-glucosidase profiling was used in combination with high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy for identification of metabolites responsible for the α-glucosidase inhibitory activity. Quercetin (1) and its dimer (2), trimer (3), and tetramer (4) were identified as main α-glucosidase inhibitors in A. ascalonicum peel, whereas (E)-piceatannol 3'-O-ß-D-glucopyranoside (5), (E)-rhapontigenin 3'-O-ß-D-glucopyranoside (6), (E)-piceatannol (8), and emodin (12) were identified as main α-glucosidase inhibitors in R. palmatum root.

The Low FODMAP Diet and Its Application in East and Southeast Asia

There is growing interest in using food choice/dietary change to influence clinical outcomes in patients with irritable bowel syndrome (IBS). The low fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs) diet is an evidence-based approach that is gaining popularity in many Western countries. The low FODMAP diet is based on restricting dietary intake of short chain carbohydrates that are slowly absorbed or indigestible and not absorbed during passage through the small intestine. These are collectively described as "FODMAPs" and comprise oligosaccharides (mostly fructans, galacto-oligosaccharides), sugar polyols, fructose in excess of glucose, and lactose in lactose malabsorbers. The general strategy of the diet is to avoid foods high in FODMAPs and replace them with foods low in FODMAPs, with long-term restriction limited to what is required to control symptoms. The likely mechanism of action is minimisation of the stimulation of mechanoreceptors exerted by distension of the intestinal lumen with water from osmotic effects and gases from bacterial fermentation in those with visceral hypersensitivity. The success of this dietary approach greatly depends on detailed knowledge about the FODMAP composition of food commonly consumed in that country. While the content of foods associated with East and Southeast Asian cuisines has not been fully explored, major high FODMAP sources are frequently used and include onion, garlic, shallots, legumes/pulses, and wheat-based products. Thus, this dietary approach holds great promise in treating IBS patients in East and Southeast Asia. The aim of this review is to highlight how the diet is implemented, its efficacy, and troublesome ingredients frequently used in Asian dishes.