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• Β-sitosterol content was measured first time in different organs of okra. • Bioactive compound contents varied greatly between organs and accessions of okra. • Outstanding accessions with higher levels of bioactive compounds were screened out. • Multivariate analysis of bioactive compounds distinguished and grouped clearly all accessions. • This work provided valuable information on the bioactive compounds in Iranian okra to use in breeding programs. Interest in the bioactive compounds in okra has piqued because of its nutraceuticals, therapeutic properties, and health benefits. Okra has been the subject of several studies, most of which have focused mainly on the properties and concentrations of polyphenols and polysaccharides or their distribution in one organ. Hence, the present study is the first attempt to measure β-sitosterol (BSS) in different organs (leaf, seed, and pod) of 20 accessions of okra commonly cultivated in Iran. Total phenol (TPC), flavonoid (TFC), radical scavenging capacity (AOA), total polysaccharide (TOP), protein content (PT), Total soluble sugar (TSS), proline content (PR), seed oil content, and profile of fatty acids were also assessed. The results indicated that the highest TPC, TFC, and AOA levels were recorded in the A13 (Khorasan Razavi) pods, while TOP, YP, and TSS were highest in A19 (Isfahan) pods. Moreover, PT and BSS levels were highest in A4 seeds from Sistan and Baluchestan. The oil content of okra seed ranged from 22.57% (A3, West Azerbaijan) to 42.30% (A7, Sistan and Baluchestan) among studied accessions. Linoleic acids and palmitic acid were found to be the most abundant fatty acids (42.50% to 52.15% and 27.63% to 31.8%) in all accessions. Principal component analysis and hierarchical cluster analysis confirmed that A19, A13, A4, A7, and A12 are suitable for breeding programs because of their nutritional value, including high polyphenol, oil, linoleic acid, and phytosterol contents. These findings suggest enhancing the exploitation of okra organs such as seeds for oil, PT, and BSS and pods and leaves for TPC, TFC, and TOP and provide valuable information on bioactive compounds in Iranian accessions of okra to use in breeding programs and the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

• Rice water was selected as the cheapest carbon source for formulating rice water medium in order to optimize biosurfactant synthesis by Pseudomonas aeruginosa. • The in vitro and in vivo antifungal efficacy and biocontrol strategy of the biosurfactant against Fusarium wilt of Abelmoschus esculentus were demonstrated. • The identification of the rhl gene, TLC, FT-IR, HPLC, and GC–MS analyses suggested the biosurfactant was rhamnolipid. • The biosurfactant that has been produced will aid in large-scale commercialization and will replace the usage of chemical surfactants in agricultural wastes. Biosurfactants, in comparison to chemical surfactants, have a greater impact on various applications due to their stability, degradability, and other physicochemical characteristics. Increasing yield and lowering production costs are critical to enhancing biosurfactant efficiency. Because biosurfactant production costs are determined by the least expensive substrate, agro-based industrial waste is one of the most promising economic strategies. Therefore, in this study we aimed to achieve the biosurfactant production in Pseudomonas aeruginosa by low cost rice medium using Response surface methodology (RSM) and assessed their competence in controlling the Fusarium wilt of Abelmoschus esculentus. Initially, the selected strain P. aeruginosa PBS29 was confirmed using 16S rRNA sequencing. Then, the 20% (v/v) of rice water was chosen as the cheapest carbon source for formulating rice water medium to optimize biosurfactant production using Central Composite Design. Enhanced biosurfactant yield of 9.35 g/l was attained through RSM by 0.59 fold higher than preliminary analysis. The model was significant with a regression coefficient of 0.98. The optimal condition was identified as 1.18% (w/v) nitrogen source [glutamic acid], pH 6.8, temperature at 37.4 °C, 2.5% (v/v) inoculum size, and 167.9 rpm agitation. In-vitro antifungal activity and biocontrol strategy of the biosurfactant demonstrated against Fusarium wilt of Abelmoschus esculentus at 100 μg/ml concentration by both soil drenching and foliar spray by pot trial. Furthermore, the detection of rhl gene, TLC, FT-IR, HPLC and GC–MS analyses suggested that the biosurfactant is rhamnolipid. Overall, in this study, the biosurfactant was synthesized using inexpensive rice water and substantiated its safe use as a biocontrol agent, which will help large-scale commercialization and interchange chemical surfactant used in agricultural wastes. [ABSTRACT FROM AUTHOR]

Rot disease is responsible for serious economic losses related to okra (Abelmoschus esculentus) crops cultivated in Upper Egypt. Colonies with a consistent morphology were isolated from the infected okra stems and leaves and subjected to morphological and molecular examinations. The causal pathogen was identified as Cochliobolus spicifer based on morphological fungus descriptions, as well as on the amplified 28S rDNA and internal transcribed spacer region (ITS) sequences, which showed 99%–100% similarity to the sequences of C. spicifer - CSN-20 strains. The volatile and non-volatile organic compounds (VOCs and n-VOCs, respectively) produced by the endophytic fungi that are associated with the medicinal plant Solenostemma arghel , namely Fusarium solani -F4-1007, Penicillium verrucosum -F2-1006, and Aspergillus terreus -F5-1008, inhibited the growth of the C. spicifer pathogen by 34.2%,31.4%, and 30.5%, respectively. In total,27 VOCs were identified by GC/MS, among which eight were specific to A. terreus -F5-1008, eight to P. verrucosum -F2-1006, and three to F. solani -F4-1007, whereas nine VOCs were commonly produced by the three endophytic fungi. Moreover, F. solani -F4-1007-produced VOCs and n-VOCs exhibited the highest antifungal activity, with 37.27% and 37.1% inhibition against C. spicifer colony growth, respectively. The potent antifungal VOCs produced by F. solani -F4-1007 were identified as 3,4-dihydro-2 h-1,5-(3″-t-butyl) benzodioxepine, 4-(2-hydroxyethyl) phenol, and phenylethyl alcohol using GC/MS. Therefore, F. solani -F4-1007 was tested as a potential biocontrol agent against C. spicifer- CSN-20 using an in-planta assay. Okra plants treated with endophytic F. solani -F4-1007did not show any disease symptoms, whereas those that were not treated with F. solani -F4-1007 exhibited severe disease symptoms when challenged with inoculation of the C. spicifer pathogen. Our results demonstrated the contribution of the endophytic fungus F. solani -F4-1007 as a potential biocontrol agent against the C. spicifer pathogen, to improve okra growth. [ABSTRACT FROM AUTHOR]

In plants, NO has been proved the function of improving abiotic stress resistance. However, the role of NO in the lignin metabolism of okra under cold stress has not been clarified. Here, histochemical staining and lignin content analysis showed that cold stress promoted the lignin accumulation of cold stored okra pods, and NO inhibited the lignin accumulation and delayed lignification process. To better understand the roles of NO in okra cold stress resistance mechanism, the full-length transcriptome data of 'Hokkaido' was analyzed. The SNP-treated okra transcriptome and cPTIO-treated okra transcriptome were obtained. A total of 41957 unigenes were screened out from three groups at 10 d, among which, 33, 78 and 18 DEGs were found in ddH 2 O-treat, SNP-treat and cPTIO-treat group, respectively. Transcriptomic data suggested that the genes involved in lignin biosynthesis showed downregulation under SNP treatment. Transcriptomic data and enzyme activity showed that exogenous NO significantly promoted the biosynthesis of endogenous NO by enhancing NOS activity. Transcriptomic data and plant hormone data showed that NO played an important role in the process of inhibiting the ethylene and ABA synthesis mechanism of okra and thereby reducing the endogenous ethylene and ABA content under chilling stress. Relevant physiological data showed that NO helped to the protection of ROS scavenging system and removed the MDA and H 2 O 2 induced by cold stress. These results provided a reference for studying the molecular mechanism of nitric oxide delaying the lignification of okra, and also provided a theoretical basis for postharvest storage of vegetables. • Nitric oxide (NO) could inhibit the lignin accumulation and delay lignification process of okra pods under cold stress. • The full-length transcriptome data of okra with NO treatment was analyzed using PacBio SMRT three-generation high-throughput sequencing technology. • Transcriptomic data and plant hormone data showed that NO played an important role in reducing the endogenous ethylene and ABA content under cold stress. • NO also functions in protecting the ROS scavenging system, thereby eliminating the MDA and H 2 O 2 induced by cold stress. [ABSTRACT FROM AUTHOR]

Drought poses a major challenge to global agricultural crop production, as it is considered one of the most severe abiotic stresses. Understanding the effects of exogenous microbial biofertilizer on okra [ Abelmoschus esculentus (L.) Moench] under drought stress can lead to new strategies for coping with drought conditions. The objective of the study was to examine the effects of microbial biofertilizer on growth, physio-biochemical traits, fruit yield, and water productivity of okra under drought stress. A factorial pot experiment, consisting of eight biofertilizer treatments applied as a soil drench (autoclaved inoculum [control], and inoculation with arbuscular mycorrhizal fungi [AMF], phosphate-solubilizing fungi [PSF], plant growth-promoting rhizobacteria [PGPR], AMF + PSF, AMF + PGPR, PGPR + PSF, and AMF + PSF + PGPR) and three soil moisture regimes (50%, 75%, and 100% field capacity [FC]), was carried out. The results indicated that decreasing soil moisture level severely affected growth and fruit yield of okra. The application of microbial biofertilizer effectively enhanced growth, fruit yield, and physio-biochemical traits of okra under different soil moisture levels. Among the biofertilizer treatments considered, the combined application of AMF and PGPR showed remarkable efficacy in enhancing growth and productivity of okra plants under both 75% and 100% FC conditions. This co-inoculation significantly boosted shoot dry matter by 51%, root dry matter by 73%, fruit yield by 113%, and irrigation water productivity by 122% compared with plants grown without inoculation, irrespective of soil moisture levels. Furthermore, the plants treated with AMF and PGPR exhibited a noteworthy decrease in free proline accumulation by 31% compared with their non-inoculated counterparts. The results suggest that application of both AMF and PGPR biofertilizer to soil is an effective strategy to alleviate moderate drought stress. It is recommended to apply AMF and PGPR in combination to improve okra yield and water productivity under drought stress. • We evaluated the effects of biofertilizer on fruit yield and water productivity of okra under drought stress. • Decreasing soil moisture level severely affected growth and yield of okra. • Application of biofertilizer effectively enhanced yield and water productivity of okra. • Co-inoculation of AMF and PGPR exhibited promising results. • It is recommended to apply AMF and PGPR in combination to improve okra yield and water productivity under drought stress. [ABSTRACT FROM AUTHOR]

Okra (Abelmoschus esculentus L. Moench) is an important tropical and subtropical crop species, but okra pods age rapidly after they meet harvest standards. The underlying mechanisms by which okra pods harden are unclear. In this study, we determined the cellulose and lignin contents of 'Chaowuxing' okra pods from 4 to 14 days postanthesis (DPA). Based on the histochemical staining of okra fruit during the active period of cellulose accumulation, we found that the hardening of okra fruit is due to the rapid accumulation of cellulose in the cell walls of vascular cells in the pulp. We used RNA-sequencing (RNA-Seq) analyses to investigate the genes that regulate okra fruit aging. Transcriptome sequencing data showed that after 7 DPA, expression of the cellulose synthase gene (CesA) decreased with time. In addition, expression of the gene encoding the first functional enzyme involved in cellulose hydrolysis (endoglucanase) also decreased, but its rate of decrease was much faster than that of the CesA. The quantitative real-time PCR (qRT-PCR) results were consistent with the RNA-Seq data. Accordingly, we speculate that the accumulation of cellulose during okra pod hardening occurs via a reduction in cellulose hydrolysis activity. The above results suggest that thickening of the cell wall caused by a significant increase in cellulose content in the vascular bundles causes okra hardening. The accumulation of cellulose is not directly achieved via increased expression of CesA but rather indirectly via decreased hydrolysis of cellulose. • The thickening of the cell wall caused by a significant increase in cellulose content causes okra hardening. • The accumulation of cellulose is not directly achieved by an increase in expression of CesA. • The accumulation of cellulose is indirectly achieved by a reduction in cellulose hydrolysis. [ABSTRACT FROM AUTHOR]

The Iranian energy sector has recently discovered a great interest in the concept of renewable and clean energy. The interest is motivated primarily by concerns about greenhouse gas (GHG) emissions and global climate change, as well as the desire to find alternative and sustainable energy sources and create potential job opportunities related to these new technologies for future generations of Iranians. This study supports the search for alternative, sustainable energy sources by assessing okra's usability as a biofuel. Okra is an annual, warm season crop that provides a rich source of industrial oil and protein. According to our investigation, the seeds of Iranian okra ecotypes that have an oil content of 20% could produce up to 325 kg/ha oil yield. Our study on Iranian okra seed oil showed that, the most dominant fatty acids of are linoleic acid (C18:2) (38–40%), Palmitic acid (C16:0) (29–30%), and Oleic acid (C18:1) (19–22%). The biodiesel derived from okra via a transesterification reaction using an ultrasonic system could meet ASTM D6751 standards with satisfactory results in methyl ester content (more than 96%), viscosity (2.3–2.4 mm −2 /S, and flash point (155–158 °C)). Because of its high oil yield, quality, and large ecological adaptation window, okra is a strong contender to provide a new source of non-edible oil for biodiesel production in bioenergy farms. [ABSTRACT FROM AUTHOR]

Abelmoschus esculentus is largely cultivated in Northeastern Brazil for medicinal purposes, e.g. inflammatory conditions. This study aimed to evaluate the efficacy of Abelmoschus esculentus lectin (AEL) in reducing formalin-induced temporomandibular joint inflammatory hypernociception in rats. The behavioral experiments were performed in male Wistar rats (180–240 g). Rats were pre-treated (i.v.) with AEL (0.001, 0.01 or 0.1 mg/kg) 30 min before formalin injection (i.art.). To analyze the possible effect of opioid pathways on AEL efficacy, animals were pre-treated with naloxone or CTOP (μ opioid receptor antagonist), naltrindole (δ opioid receptor antagonist) or nor-binaltorphimine (κ opioid receptor antagonist) (i.t.) 15 min before AEL administration followed by intra-TMJ injection of 1.5% formalin. Animals were monitored for a 45-min observation period. TMJ tissue, trigeminal ganglion, and subnucleus caudalis were collected for TNF-α dosage (ELISA). In addition, the vascular permeability was evaluated by Evans Blue extravasation. AEL significantly reduced formalin-induced TMJ inflammatory hypernociception and decreased Evans blue extravasation. It decreased TNF-α levels in the TMJ tissue, trigeminal ganglion, and subnucleus caudalis. AEL antinociceptive effects were not observed in the presence of naltrindole or nor-binaltorphimine, suggesting that AEL efficacy depends on TNF-α inhibition and the activation of δ and κ opioid receptors. AEL has provided prominent analgesic and anti-inflammatory effects in this pre-clinical model of TMJ, supporting its possible use as a pharmacological tool for the management of painful conditions. [ABSTRACT FROM AUTHOR]

Phenolics play a key role in communication between plants and microbes in the rhizosphere. In this study, shikimic, gallic, fumaric, ferulic, vanillic acid and quercetin in root exudates of Abelmoschus esculentus act as chemoattractants of endophytic Alcaligenes faecalis strains, BHU 12, BHU 16 and BHU M7. In vitro chemotaxis assay showed that BHU 12 expressed highest chemotactic movement (CFU ∼50 × 10 12 ) towards A.esculentus root exudates followed by BHU 16 and BHU M7 (CFU∼ 9 × 10 12 ), thereby confirming their ability to colonize the host rhizoplane region. However, BHU 16 expressed highest biofilm formation ability followed by BHU 12 and BHU M7. Assessment of chemotactic and biofilm formation potential towards individual phenolic acids revealed BHU 12 to be maximally attracted towards 1 μM shikimic acid (2 × 10 15 ) while BHU 16 towards 1 mM vanillic acid (6.5 × 10 12 ) and BHU M7 towards 1 mM ferulic acid (3.5 × 10 12 ), thereby confirming the phenolic acid components responsible for particularly attracting the endophytic isolates. Upon colonization, the endophytic isolates modified the phenolic profiles of root exudates in planta in a manner so as to plausibly attract more of the beneficial rhizospheric microbiota as well as self-fortification against pathogenic microbes. This hypothesis was verified by monitoring the changes in phenolic components of A. esculentus root exudate owing to S. rolfsii infection, a disastrous soil-borne pathogen. Thus, on the whole, the work provides intricate details of plant-endophyte interactions for biotic stress management through careful manipulation of root exudates, thereby aiding in sustainable agriculture. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine the effect of fruit size on nutritional value, chemical composition and antioxidant properties of Mediterranean okra genotypes. For this purpose, pods from four okra cultivars and local landraces commonly cultivated in Greece, as well as pods from four commercial cultivars from North America were collected at two sizes (3–5 and >7 cm). Significant differences were observed between the studied genotypes for both nutritional value and chemical composition parameters. Small fruit had a higher nutritional value, whereas chemical composition differed in a genotype dependent manner with most of the studied cultivars showing better results when harvested in small size. In conclusion, fruit size has a genotype dependent impact on chemical composition and nutritional value of okra pods and the common practice of harvesting okra fruit while they still have a small size helps to increase nutritional value for most of the studied genotypes. [ABSTRACT FROM AUTHOR]

Background and objective In present investigation, ultrasonic assisted followed by microwave irradiation involving extraction process was developed under the umbrella of Box-Behnken design for gaining superior yield of gum from okra fruit, Abelmoschus esculentus . Methods and results Stationed on single factor layout, Box-Behnken design was employed to calculate the optimized conditions for isolating the okra fruit gum (OFG) using ultrasonic waves and microwave radiations. The extracted gum was further characterized for particle size, zeta-potential, surface morphology, thermal stability, functional groups, and polymorphism. The optimized conditions like water to raw material ratio of 44.98 ml/g, extraction time of 40 min and ultrasonic power of 60 W provided the uppermost extraction yield of 31.52% ± 0.22% that was analogous to the predicted value. The average mean diameter of OFG was measured to be 256.3 ± 18.4 nm in addition to the zeta potential of −9.85 ± 0.12 mV. SEM image of OFG powder revealed irregular, rough surfaced and amorphous structure of OFG powder. The degree of esterification was measured to be 7.8 with high thermal stability, as exposed by DSC. The FT-IR spectrum of OFG displayed a broad peak at 3405.20 cm −1 announcing presence of OH group and hydrophilicity attribute. The spectrum also presented the small peak at 1605.20 cm −1 ( C O) owing to the presence of galacturonic acid besides galactose and rhamnose. Conclusion In conclusion, ultrasound and microwave irradiation assisted extraction process under the shed of Box-Behnken design offered superior yield of OFG that may be used as a pharmaceutical excipient for designing medicated or health products. [ABSTRACT FROM AUTHOR]

Okra (Abelmoschus esculentus L.) is a tropical crop species, and its growth and development are severely affected by cold stress. Recent studies have identified a potential association between WRKY transcription factors and the cold response mechanism of crops. In this study, the AeWRKY32 transcription factor that encodes 482 amino acids was amplified from A. esculentus , and its expression level was found to be the highest in the okra flower. AeWRKY32 localized to the nucleus and displayed transcriptional activation capability. Under normal conditions, overexpression of AeWRKY32 induced anthocyanin accumulation, with higher expression levels of AtCHS1 , AtCHI4 , AtF3H1 , and AtDFR2 in transgenic Arabidopsis. Under cold stress, anthocyanin levels were further elevated in transgenic Arabidopsis plants. At the same time, AeWRKY32 overexpression promoted ABA biosynthesis, inhibited H 2 O 2 and O 2 − generation, induced stomatal closure, reduced electrolyte leakage, and thus improved the cold resistance of transgenic Arabidopsis. Furthermore, under cold stress, the expression profiles of AtCOR413 , AtCOR15B , AtCBF1 , and AtCBF2 were upregulated in transgenic Arabidopsis. Overall, our study provides evidence that AeWRKY32 serves as a crucial regulator in both anthocyanin accumulation and cold tolerance of transgenic Arabidopsis. Our findings could provide insights into the molecular mechanism linking AeWRKYs to plant cold tolerance. • Overexpressing AeWRKY32 induced anthocyanin accumulation in transgenic Arabidopsis under normal and cold conditions. • ABA synthesis was activated in transgenic Arabidopsis , leading to suppression of ROS burst and enhanced stomatal closure. • Expression levels of cold response genes were higher in transgenic Arabidopsis. [ABSTRACT FROM AUTHOR]

Sclerotium rolfsii is a highly aggressive pathogen that causes huge economic losses, especially in temperate climates. Alcaligenes faecalis , particularly in endophytic form, has rarely been used to control this fungus. In this study, endophytic Alcaligenes sp. strain BHU 12, BHU 16 (isolated from Abelmoschus esculentus leaf) and BHU M7 (isolated from Andrographis paniculata leaf) were reported to trigger a wide range of host defenses in Okra plant against the collar-rot pathogen S. rolfsii . Endophytic colonization of the strains in ten days old plants was assessed through re-isolation of the rif-tagged strains on rifampicin augmented nutrient agar media. The ability of the endophytic strains to induce systemic defense responses in above-ground organs was assessed by collecting leaf tissues of the Okra plants grown under non-gnotobiotic conditions at different time intervals post seedling bacterization with the endophytic biocontrol agents. The pathogen challenged unprimed plants exhibited flaccidity of the stem and leaves at 48 h post infection (hpi) in contrast to the bioprimed and challenged plants. Biochemical and histochemical analyses explained the above phenomenon as activation of phyto-peroxidases leading to an increased metabolism of the reactive oxygen species (ROS), accompanied by activation of the phenylpropanoid network and a subsequent enhancement in plant phenolics. Interestingly, though the maximum increase in the defense pathways was observed in treatments with native endophytes of Okra plant, yet the enhancement in antioxidant pathway due to A. paniculata borne endophytes was also quite significant. Thus, this work clearly demonstrates how Okra plants respond to the “non-hostile” colonization of bacterial endophytes and how induced defense response can contribute to the biocontrol activity of the endophytic strains. [ABSTRACT FROM AUTHOR]

Temporomandibular joint (TMJ) disorders show inflammatory components, heavily impacting on quality of life. Abelmoschus esculentus is largely cultivated in Northeastern Brazil for medicinal purposes, having it shown anti-inflammatory activity. We evaluated A. esculentus lectin (AEL) efficacy in reducing zymosan-induced temporomandibular joint inflammatory hypernociception in rats along with the mechanism of action through which it exerts anti-inflammatory activity. Animals were pre-treated with AEL (0.01, 0.1 or 1 mg/kg) before zymosan (Zy) injection in the TMJ to determine anti-inflammatory activity. To analyse the possible effect of the hemeoxygenase-1 (HO-1) and the nitric oxide (NO) pathways on AEL efficacy, animals were pre-treated with ZnPP-IX (3 mg/kg), a specific HO-1 inhibitor, or aminoguanidine (30 mg/kg), a selective iNOS inhibitor, before AEL administration. Von Frey test evaluated inflammatory hypernociception, synovial fluid collection was performed to determine leukocyte counting and myeloperoxidase (MPO) activity 6 h after Zy injection, and Evans Blue extravasation determined vascular permeability. TMJ tissue was collected for histopathological analysis (H&E) and immunohistochemistry (TNF-α, IL-1β, HO-1). In addition, TMJ tissue and trigeminal ganglion collection was performed for TNF-α and IL-1β dosage (ELISA). AEL increased inflammatory nociceptive threshold, reduced leukocyte influx along with MPO activity, leukocyte influx into the synovial membrane, and Evans Blue extravasation. It promoted HO-1 overexpression whilst decreased TNF-α and IL-1β expression in the TMJ tissue. AEL reduced TNF-α and IL-1β levels in TMJ tissue and trigeminal ganglion. AEL effects, however, were not observed in the presence of ZnPP-IX. These findings suggest that AEL efficacy depends on TNF-α/IL-1β inhibition and HO-1 pathway integrity. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) improves the scavenging capacity of reactive oxygen species (ROS) in postharvest fruit and vegetable, but the effect of exogenous GSH in okra (Abelmoschus esculentus) has not been clarified. This study investigated the effect of GSH on ROS scavenging in postharvest okra and found that GSH treatment effectively inhibited weight loss and alleviated browning and thereby maintained the appearance and quality of the fruit. Moreover, GSH suppressed levels of hydrogen peroxide (H 2 O 2), superoxide radical (O 2 -), and malondialdehyde (MDA). Treatment with exogenous GSH increased the contents of ascorbic acid (AsA) and GSH in okra, while decreased the contents of dehydroascorbic acid (DHA) and oxidized glutathione (GSSG). GSH treatment also enhanced the ROS-scavenging ability of okra by upregulating the expression of AeAPXs , AeGRs , AeMDHARs and AeDHARs , all of which are associated with redox homeostasis. Collectively, our findings demonstrate that exogenous GSH treatment can extend the shelf life of okra by mediating redox homeostasis. • Exogenous GSH could effectively maintain the quality of okra. • Exogenous GSH could maintain redox homeostasis during okra storage. • GSH enhanced the ROS-scavenging ability by altering related genes expression. • GSH enhanced the activity of the AsA-GSH cycling enzymes. [ABSTRACT FROM AUTHOR]

Okra (Abelmoschus esculentus (L.) Moench) is traditionally used by different populations of Africa, América, Asia, and Europa to control diabetes. Although its action has been evaluated in several preclinical rodent trials, they have not been systematically analyzed. To evaluate the effectiveness of using okra in the treatment of diabetes in experimental rodent models. Controlled and randomized rodent animal trials with induced diabetes published between January 2000 and January 2021 were searched in the PubMed, Scopus, Scielo, and Web of Science databases. The search strategy included studies comprising the descriptors: animal species, diabetes induction method, intervention time, part of okra fruit used (whole, seeds, or peels), and dose as well as observed effects on biochemical and metabolic parameters. The systematic review was carried out according to the PRISMA statement, Cochrane bias risk tool (SYRCLE's RoB tool), and registered for systematic review protocols (PROSPERO). A total of 326 articles were identified and after the exclusion of studies with gestational animal models, non-rodent animals, and non-diabetic animals, 11 studies involving 388 rodents were selected for the synthesis of results. The diabetes induction methods included streptozotocin, streptozotocin-nicotinamide, alloxan monohydrate, insulin resistance by high-fat diets or formulation described in AIN - 76, and feeding with high-fat food. Both Wistar albino rats, Sprague-Dawley males, and rats of both sexes of the Long-Evans lineage as well as male albino mice and C57BL females were included in the experiments. Studies showed that extracts of the fruit, the fresh fruit, or its various fractions had positive effects on the following markers: glycated hemoglobin, cholesterol, HOMA-IR, oral glucose tolerance test, and blood glucose, in acute (2 and 24 h), and chronic (up to 4 months) treatment. An important hypoglycemic effect of okra in its various fractions on induced diabetes was observed by different authors. Moreover, okra promoted improvement in metabolic markers such as insulin sensitivity, lipid profile, and bodyweight loss. [Display omitted] • Okra in its various fractions has hypoglycemic effect on induced diabetes in rodents. • Ethanol extract of okra has a significant effect on reducing blood glucose levels. • The hypoglycemic effect of okra was observed in acute or chronic treatment. • Okra promoted improvement in metabolic markers such as insulin sensitivity, lipid profile, and bodyweight loss. [ABSTRACT FROM AUTHOR]

In this study, the microbial fermentation characteristics of okra pectic-polysaccharide (OPP) and its degraded products (DOPP-1 and DOPP-3) with different molecular weights (M w) and degrees of branching (DB) were investigated, and related impacts on gut microbial composition were also revealed. Results indicated that microbial fermentation characteristics of OPP were obviously affected by its different structural features. The fermentabilities of OPP (high M w and DB), DOPP-1 (middle M w and DB), and DOPP-3 (low M w and DB) were measured to be 49.49%, 58.34%, and 48.16%, indicating that the utilization of total carbohydrates of DOPP-1 was relatively higher compared to OPP and DOPP-3. The ways in which gut bacteria metabolized OPP, DOPP-1 and DOPP-3 were quite different, and a lower M w and a higher DB were more beneficial to the fermentation by intestinal bacteria. Additionally, selective modulations of gut microbial composition by different types of okra pectic-polysaccharides were observed. Both OPP and DOPP-1 could increase relative abundances of several beneficial bacteria, such as Bacteroides and Phascolarctobacterium. While DOPP-3 could notably improve relative abundances of Megasphaera and Megamonas. Results suggested that the modulation of gut microbiota by okra pectic-polysaccharide was structure-dependent, and both DB and M w played critical roles in the selective modulation of gut microbial composition. Collectively, our findings are beneficial to revealing the potential relationship between chemical structures of OPP and its gut microbial fermentation characteristics, which are also helpful for the design of potential OPP for selective modulation of beneficial bacteria in the gut. [Display omitted] • Microbial fermentation characteristics of okra pectic-polysaccharide (OPP) were studied. • Molecular weight (M w) and branched chain notably affected its fermentation characteristics. • A lower M w and a higher degree of branching are more beneficial to the fermentation. • OPP and its degraded products could selectively modulate the microbial composition. • The modulation of gut microbial composition by OPP is structure-dependent. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DtM) is a collection of recurrent metabolic abnormalities that are generally assessed by persistent hyperglycemia. This condition occurs when the insulin released from the pancreatic cells get destroyed and produce little or no insulin. In traditional Chinese medicine, Abelmoschus esculentus (AS) is used for the treatment for type 1 diabetes. This study aims to mitigate type 1 DtM caused by the administration of streptozotocin (STZ). Diabetes was produced in each of the Wistar rats by administering a single shot administration of STZ intraperitoneally. The rats were split into five groups. Group1 and 2 were normal control and diabetic control group. Groups 3, 4, and 5 were received okra mucilage extract and okra seed crude extract at a dosage of 150 mg/kg, 200 mg/kg, and 200 ml/kg. After 4 weeks animals were sacrificed and blood was collected through cardiac puncture and liver and kidney were dissected for further biochemical as well as histopathological examinations. The FBG, %HbA1c, lipid profile, liver function test, oxidative stress, and histopathology investigation were analyzed. Our result showed a significant difference between different groups in each parameter. Our study revealed that okra mucilage extract has advantage over okra seed crude extract significantly. The extract of AS has an antidiabetic activity and contributes to the overall reduction in BG levels. Its properties can be a remedy to manage DtM. Based on the results of the tests, it was determined that a solid oral formulation might be made using okra-derived mucilage crude extract and aqueous seed extract as a pharmaceutical excipient. [ABSTRACT FROM AUTHOR]

In evidently the first study of its kind, vermicompost derived solely from a weed known to possess plant and animal toxicity was used to assess its impact on the germination and early growth of several plant species. No pre-composting or supplementation of animal manure was done to generate the vermicompost in order to ensure that the impact is clearly attributable to the weed. Whereas the weed used in this study, Lantana ( Lantana camara ), is known to possess strong negative allelopathy, besides plant/animal toxicity in other forms, its vermicompost was seen to be a good organic fertilizer as it increased germination success and encouraged growth of all the three botanical species explored by the authors – green gram ( Vigna radiata ), ladies finger ( Abelmoschus esculentus ) and cucumber ( Cucumis sativus ). In terms of several physical, chemical and biochemical attributes that were studied, the vermicompost appeared plant-friendly, giving best results in general when employed at concentrations of 1.5% in soil (w/w). Fourier transform infrared spectrometry revealed that the phenols and the sesquiterpene lactones that are responsible for the allelopathic impact of Lantana were largely destroyed in the course of vermicomposting. There is also an indication that lignin content of Lantana was reduced during its vermicomposting. The findings open up the possibility that the billions of tons of phytomass that is generated annually by Lantana and other invasives can be gainfully utilized in generating organic fertilizer via vermicomposting. [ABSTRACT FROM AUTHOR]

The use of a new biosorbent derived from Abelmoschus esculentus (A. esculentus) seed for the removal of Acid Blue 113 (AB113) in aqueous solutions was investigated in batch mode. Biosorption studies were carried out under varying operational parameters including initial pH, biosorbent dosage, contact time, initial dye concentration and temperature. The results indicated that the biosorption properties were strongly dependent on initial pH. Fourier transform infrared spectroscopy analysis revealed that hydroxyl, carboxylic and amide functional groups present on the biosorbent surface were involved in the dye removal process. Equilibrium data were best fitted by the Langmuir model. The maximum biosorption capacity was 169.9 ± 3.1 mg g-1 at 25 °C and initial pH 5.5. The kinetic data were in good agreement with the pseudo-second-order kinetic model. The process was controlled by diffusion through boundary layer at the initial stage followed by intra-particle diffusion at the later stage. Thermodynamic evaluation showed that the process was endothermic and spontaneous. The present study suggests that A. esculentus seed with maximum biosorption capacity which compared well with values reported in the literature can be a potential biosorbent for AB113 dye removal. [ABSTRACT FROM AUTHOR]

Highlights: [•] Phenotypic description and AFLP analysis of local and imported okra genotypes were performed. [•] Greek germplasm fell into three groups with no overlap based on molecular markers. [•] AFLP analysis revealed low (12%) polymorphism and distinct geographical groupings. [•] Greek germplasm constitutes a significant pool of phenotypical variation. [•] Seed germination may relate to the phenotypes’ geographical origin: island/mainland. [ABSTRACT FROM AUTHOR]

Abstract: The root-knot nematode, Meloidogyne incognita, is one of the major limiting factors affecting plant growth and yield causing an estimated $100 billion loss per year worldwide. Synthetic pesticides, though instantaneously effective, are usually prohibitively expensive, not readily available, may cause hazards to both man and livestock, and inflict injury to the environment. Notable among the alternatives to nematicides is the use of resistant cultivars which are inexpensive and eco-friendly. In the present studies, twelve okra (Abelmoschus esculentus L) cultivars were evaluated for their resistance against M. incognita under field conditions. Ten-day old okra plants of test cultivars were inoculated with 3000 freshly hatched second stage juveniles of M. incognita. The nematode caused reductions in various growth parameters of all the cultivars to varying levels over their respective controls. None of the cultivars was found completely resistant. The cultivar ‘Sharmeeli’ was highly susceptible as >100 galls were recorded on the roots. Sharmeeli also showed maximum reductions in growth among the cultivars evaluated. The cultivars Anmol and Sindha were susceptible with 71–100 galls. The cultivars Sabz Pari, Super Star, PMS-55 and PMS Beauty were moderately susceptible with 31–70 galls and comparatively less reductions in growth. Cultivars Sanam, Dikshah, Arka Anamika, Ikra-1 and Ikra-2 with 11–30 galls were rated as moderately resistant and showed less damage by the nematode as compared to susceptible cultivars and their planting could provide a useful tool to control root-knot nematodes. [Copyright &y& Elsevier]

Highlights: [•] Sequence diversity of begomoviruses and DNA satellites in okra from Cameroon. [•] Leaf curl disease common in the crop plant okra. [•] Three different begomoviruses were found, including a new species. [•] Okra plants were infected by one betasatellite and two divergent alphasatellites. [•] There is a high diversity of begomoviruses and DNA satellites in West Africa. [Copyright &y& Elsevier]

Abstract: A combined leaf and pod transcriptome of okra (Abelmoschus esculentus (L.) Moench) has been produced by RNA sequencing and short read assembly. More than 150,000 unigenes were obtained, comprising some 46million base pairs of sequence information. More than 55% of the unigenes were annotated through sequence comparison with databases. The okra transcriptome sequences were mined for simple sequence repeat (SSR) markers. From 935 non-redundant SSR motifs identified in the unigene set, 199 were chosen for testing in a germplasm set, resulting in 161 polymorphic SSR markers. From this set, 19 markers were selected for a diversity analysis on 65 okra accessions comprising three different species, revealing 58 different genotypes and resulted in clustering of the accessions according to species and geographic origin. The okra gene sequence information and the marker resource are made available to the research community for functional genomics and breeding research. [Copyright &y& Elsevier]

Abstract: In the present work, we describe the synthesis of gold nanoparticles (Au NPs) using seed aqueous extract of Abelmoschus esculentus and its antifungal activity. UV–visible spectroscopy, XRD, FTIR, AFM, FESEM and EDX analyses were performed to ascertain the formation of Au NPs. The synthesized Au NPs were characterized by a peak at 536nm in the UV–visible spectrum. XRD confirmed the crystalline nature of the nanoparticles of 62nm size. The XRD peaks at 38°, 44°, 64° and 77° can be indexed to the (111), (200), (220) and (311) Bragg''s reflections of cubic structure of metallic gold, respectively. The FTIR result clearly showed that the extracts containing unctional group act in capping the nanoparticles synthesis. AFM shows the 3D topological characteristic of Au NPs. FESEM images revealed that all particles were spherical with a narrow size range of 45–75nm. Antifungal activity of Au NPs were tested against Puccinia graminis tritci, Aspergillus flavus, Aspergillus niger and Candida albicans using standard well diffusion method. The maximum zone of inhibition was observed in the Au NPs against P. graminis (17mm) and C. albicans (18mm). The results suggest that the synthesized Au NPs act as an effective antifungal agent. It is confirmed that Au NPs are capable of rendering high antifungal efficacy and hence has a great potential in the preparation of drugs used against fungal diseases. [Copyright &y& Elsevier]

Abstract: The whitefly Bemisia tabaci is one of the most important pests of the tomato Lycopersicon esculentnm in the world; it affects plant vigour, transmits geminiviruses and reduces crop quality. This experiment was conducted to determine the response of Bemisia tabaci population when tomato (Solanum lycopersicum MT1) planted alone (non-choice), tomato planted with brinjal (Solanum malagna MTe1), tomato with chilli (Capsicum annuum MC11), tomato with okra (Abelmoschus esculentus MKBE1), and all together (choice experiment) under glasshouse conditions (30-36°C, 80% RH). The results have shown that, there were significantly higher (P< 0.05) numbers of adults, eggs and nymphs on tomato alone or planted with chilli, whereas significantly lower numbers of adults, eggs and nymphs were seen when tomato was planted with okra and brinjal. Generally, the number of adults and eggs was observed to be more on the upper stratum compared to the lower plant stratum. Interestingly, the number of nymphs was found to be higher on the middle stratum than on the other strata in all treatments. [Copyright &y& Elsevier]

Okra fruit (Abelmoschus esculentus (L.) Moench) has been extensively used for the treatment of skin damage and subcutaneous tissue abscess for many years in Turkish folk medicine. In this study, we aimed to investigate the wound healing potential of okra fruit by in vitro and in vivo experimental models in detail. Furthermore, based on the results of experiments, a wound healing formulation was developed and its activity profile was studied. For this purpose, the phenolic, flavonoid and proanthocyanidin contents and chemical profile of aqueous and ethanolic extracts prepared from okra fruits cultivated in two different locations of Turkey, i.e. Aegean and Kilis regions, were comparatively determined and the tryptophan levels, which is known to be an influential factor in wound healing, were measured. Antioxidant activity of the okra fruit extracts was determined by DPPH test, ABTS radical scavenger activity, iron-binding capacity, total antioxidant capacity and copper reduction capacity assays. Moreover, antibacterial activity potentials of the aqueous and ethanolic extracts of okra fruits were determined. The protective effect of the extracts against H 2 O 2 -induced oxidative stress and anti-inflammatory activity were assessed in HDF (human dermal fibroblast) cells and in RAW 264.7 murine macrophages, respectively. The biocompatibility of the gel formulations prepared with the best performing extract were evaluated by human Epiderm™ reconstituted skin irritation test model. Wound-healing activity was investigated in rats by in vivo excision model and, histopathological examination of tissues and gene expression levels of inflammation markers were also determined. According to our findings, the aqueous and ethanolic extracts of okra fruits were found to possess a rich in phenolic content. Besides, isoquercitrin was found to be a marker component in ethanolic extracts of okra fruits. Both extracts exhibited antioxidant activity with significant protective effect against H 2 O 2 -induced damage in HDF cells by diminishing the MDA level. Also, the highest dose of ethanolic extracts has displayed a potent anti-inflammatory activity on LPS-induced RAW264.7 cells. Besides, both water and ethanolic extracts were shown to possess antimicrobial activity. On the other hand, the formulations prepared from the extracts were found non-irritant on in vitro Epiderm™-SIT. In vivo excision assay showed that tissue TGF-β and IL-1β levels were significantly decreased by the 5% okra ethanolic gel formulation. The histopathological analysis also demonstrated that collagenisation and granulation tissue maturation were found higher in 5% (w/v) okra ethanolic extract-treated group. 5% of okra ethanolic extract might be suggested as a potent wound healing agent based on the antimicrobial, antioxidant and anti-inflammatory tests. The proposed activity was also confirmed by the histopathological findings and gene expression analysis. [Display omitted] [ABSTRACT FROM AUTHOR]

• Interference with viral βC1 ORF offers YVMV resistance in transgenic okra lines. • ihpRNA cassette with sense and antisense strands was cloned in pRNAi-LIC vector. • Ligation independent cloning is an easier, PCR based strategy. • Agrobacterium mediated in planta transformation is an efficient strategy in okra. • Artificial screening with infected vectors in containment has proven the resistance. Begomovirus Yellow vein mosaic virus causes severe yield losses in okra and even the resistant lines developed through conventional breeding show susceptibility at various levels. This paper describes the development of YVMV resistant lines through RNAi strategy. A universal ihpRNA construct harbouring βC1 ORF from the β-satellite of the begomovirus was designed using pRNAi-LIC plasmid. Complementarity checks in sequence databases had shown no off-target effects by the target region and the success of siRNA in interference was proven using Custom Dicer-Substrate siRNA analysis. The βC1 ORF of the begomovirus was PCR amplified and sequenced using the primer combination designed. The pRNAi-LIC vector, a derivative of pCAMBIA2300 containing duplicated CaMV 35S promoter and Nos terminator from pYL44, was Sma I digested and the amplified sense and antisense strands of the βC1 region were cloned. E. coli transformed with the plasmid were screened for antibiotic resistance, and the plasmids confirmed for the sense and antisense regions through sequencing, were transferred to Agrobacterium tumefaciens strain GV3101. In planta transformation strategy was followed to transform a highly susceptible okra cv. Salkeerthi with ihpRNA- βC1 cassette. Transformation success, confirmed by the amplification of sense strand using the primers VLIC1 and VLIC5, was 11.42 %. Transcription of siRNA from the βC1 ORF in the transgenic lines was confirmed by its PCR amplification from the cDNA, using the stem loop primers designed (68 bp). When the transformed and healthy wild-type plants were co-grown with infected wild-type plants, inside an insect cage released with whiteflies and maintained within a containment facility, three of the four transgenic plants remained completely healthy throughout the crop span. [ABSTRACT FROM AUTHOR]

Abstract: The aims of the present work were to identify and quantify the polyphenolic profile of okra (Abelmoschus esculentus), a vegetable almost worldwide consumed. Since the knowledge about the okra polyphenolic compounds is limited, the seeds and the skins of okra were separately analyzed. The seeds, which represent the 17% of the vegetable and are richer in phenolic compounds, were mainly composed by oligomeric catechins (2.5mg/g of seeds) and flavonol derivatives (3.4mg/g of seeds). The skins polyphenolic profile was composed principally by hydroxycinnamic and quercetin derivatives (0.2 and 0.3mg/g of skins). These findings in associations with the high content of okra in carbohydrates and proteins enhance the importance of this foodstuff in the human diet. [Copyright &y& Elsevier]

[Display omitted] • Diabetes mellitus (DM), as a global health problem, is a common endocrine disorder. • Okra is a valuable plant due to its antioxidant compounds, fibers, and bioactive polysaccharides. • Okra products decline oxidative stress in diabetes due to their antioxidant compounds. • Okra products decrease blood glucose and lipid profile through soluble fibers and inhibition of digestive enzymes. Diabetes mellitus (DM) is a prevalent endocrine disorder with clinical manifestations of hyperglycemia and hyperlipidemia due to malfunction and/ or insufficiency of insulin in the body. DM is considered as a public health problem worldwide due to its adverse effects on the body. Okra (Abelmoschus esculentus L.) is an annual medicinal plant rich in antioxidant components, bioactive polysaccharides, and fibers. This systematic review aimed to summarize the effects of okra on glycemic indices and lipid profile. PubMed, Scopus, Web of Knowledge, and Google scholar databases were searched until May 2021 with no limitation. Totally, 54 studies which investigated the effects of okra on glycemic control and lipid profile were included in the present systematic review. Most of the included studies showing favorable effects of okra products on glycemic variables and lipid profile, were performed on animal models. Therefore, more clinical trials are needed for a definitive conclusion. [ABSTRACT FROM AUTHOR]