Role of pomegranate and citrus fruit juices in colon cancer prevention

Colorectal cancer is the second leading cause of cancer-related deaths in the United States.Recent studies prove that though chemotherapeutic agents are being used for the treatment of colon cancer,they become non-effective when the cancer progresses to an invasive stage.Since consumption of certain dietary agents has been linked with various cancers,fruit juices have been investigated for their consistently protective effect against colon cancer.The unique biochemical composition of fruit juices is responsible for their anticancer properties.In this review,the chemo-preventive effect of fruit juices such as pomegranate and citrus juices against colon cancer are discussed.For this purpose,the bioavailability,in vitro and in vivo effects of these fruit juices on colorectal cancer are highlighted.Moreover,there is a scarcity of studies involving human trials to estimate the preventive nature of these juices against colon cancer.This review will support the need for more preclinical tests with these crude juices and their constituents in different colorectal cancer cell lines and also some epidemiological studies in order to have a better understanding and promote pomegranate and citrus juices as crusaders against colon cancer.

Characterization of Bacterial Cellulose From Oil Palm Shoot Juices and Coconut Juice/Poly(ethylene glycol) Biocomposite

A new biocomposite was preformed between bacterial cellulose(BC)pellicle and polyethylene glycol(PEG)at different concentrations(0%,5,10%,15%and 20%)and different molecular weight(600,1000 and 2000).The structure and mechanical properties of BC/PEG biocomposite were investigated.The results indicated that the properties of the BC were improved by the addition of PEG.The morphology of the BC and BC/PEG blend was examined by a scanning electron microscope(SEM).These showed that PEG was coated with a large pore size fibril on the BC and the BC/PEG was dense with an even and smooth surface.All the Fourier transform infrared spectroscopy(FT-IR)thermograms of BC/PEG showed the same functional groups as typical BC and PEG.The DSC result showed that the thermal stability improved which might be associated with a weak interaction between BC and PEG,and may be useful for applications.

Antimicrobial Properties and Phytochemical Composition of <i>Garcinia kola, Bryophyllum pinnatum</i>, and <i>Allium sativum</i>Juices on Some Clinical Pathogens

Background: Medicinal plants have been in use since the origin of man. Many important chemical substances with biological functions that could be used for treatment and prevention of attack from bacteria, fungi, herbivorous mammals and insects are produced by different plants. Such compounds with useful properties have been recorded in their numbers, about 12,000 accounting for about 10% of total plant species. Aim: The aim of the study was to determine the antimicrobial efficacies of herbal extracts on some clinical pathogens. Methods: The antimicrobial activities of pressed juices of Allium sativum (garlic), Bryophyllum pinnatum and Garcinia kola neats and their dilutions were tested on pathogens such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus and Candida albicans to determine their susceptibility to the juices and their combinations. Agar well diffusion method was employed on Muller-Hinton agar to determine their antimicrobial susceptibility pattern. The phytochemical analysis of the plants’ juices were also determined. Results: At 100% (neat) the juices of G. kola, B. pinnatum and Garcinia kola showed substantial zones of inhibition against the pathogens with a zone diameter of about 22.0 mm and above. At 75% concentrations, the juices inhibited the pathogens tested against them. A. sativum (garlic) inhibited K. pneumonia, P. mirabilis, and S. aureus even at 50% concentration. C. albicans isolates were 60% susceptible to G. kola juice, 40% at 100% concentration. At 75% concentration of the juice, C. albicans isolates were also 60% susceptible to the juices. At 50% - 100% concentrations, C. albicans isolates were 100% sensitive to A. sativum extract. Conclusions: The medicinal plant juices tested against the pathogens possess some potentials worth exploiting as potent antimicrobial agents on gram-positive, gram-negative bacteria and the fungus.

Synthesis of highly fluorescent carbon dots from lemon and onion juices for determination of riboflavin in multivitamin/mineral supplements

In this work, lemon and onion biomasses commonly found in street markets are for the first time used to develop a facile, fast and low-cost one-step microwave-assisted carbonization method for synthesis of highly fluorescent carbon dots (CDs). The structure and optical properties of CDs were investigated by TEM, XRD, XRF, UV-Vis, FTIR, and fluorescence spectroscopy. CDs displayed satisfactory optical pro-prieties, a high quantum yield of 23.6%, and excellent water solubility, and the particle size was 4.23-8.22 nm with an average diameter of 6.15 nm. An efficient fluorescent resonance energy transfer (FRET) between the CDs and riboflavin was achieved with CDs acting as donor and riboflavin as acceptor. A linear relationship between FRET and the riboflavin concentration from 0.10 to 3.0 μg/mL was observed, allowing the development of an accurate and fast analytical method to determine this vitamin in multivitamin/mineral supplements. Despite the potential interferences in these supplements, CDs were selective for riboflavin under optimized conditions. A paired t-test at a 95% confidence level indicated no statistically significant difference between the proposed and the reference methods. Recovery test presented values ranged from 96.0% to 101.4%. The limit of detection and relative standard deviation were estimated at 1.0 ng/mL and <2.6% (n = 3), respectively. CDs were successfully synthesized in a domestic microwave oven (1450 W, 6 min), presenting satisfactory parameters when compared with results of other studies reported in the literature, suggesting that the proposed method is a potentially useful method for the synthesis of CDs and determination of riboflavin.

Anti-<i>Helicobacter</i>Activity of Certain Food Plant Extracts and Juices and Their Composition <i>in Vitro</i>

Plant material screening was performed to study anti-Helicobacter pylori activity in vitro using an agar diffusion method on Columbia blood agar. 33 substances, juices and plant extracts and 35 of their combinations were tested. Quince (Cydonia oblonga) juice demonstrated the strongest anti-H. pylori activity followed by cranberry juice. Con-centrated apple juice, plum, red currant, black chokeberry, raspberry and bilberry juice also showed significant activity. Green tea and apple pomace extract as well as sweet flag rhizome, ginger and wild bergamot extract, cherry syrup, red beet juice and whey did not exhibit anti-Helicobacter activity. Quince juice in combination with bilberry, black chokeberry, red currant juice, green tea, sweet flag rhizome or apple pomace extract as well as cranberry juice in combination with sweet flag rhizome extract demonstrated a synergistic effect on inhibition of H. pylori. The obtained results offer new perspectives for development of functional anti-Helicobacter food product(s) for dietary management of H. pylori infection. The essential components of these products could be the most active juices and extracts like quince and cranberry juice supplemented with a corresponding synergist. Further studies are required to investigate the mechanism of antibacterial action of plant products and their efficacy in vivo.

Effects of inhibitors on the protease profiles and degradation of activated Cry toxins in larval midgut juices of Cnaphalocrocis medinalis (Lepidoptera:Pyralidae)

Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.

Nutritional Composition of Orange Juice: A Comparative Study between French Commercial and Home-Made Juices

The study aimed to compare the nutritional composition of commercial and home-made orange juices with a fruit content of 100%, i.e., without dilution with water and without addition of sugars or any other sweeteners. Orange juice samples (n = 12 for both types of juice) were representative of the French market and of French consumers’ habits as determined by a consumer survey. The results showed that both types of juices contained the same concentrations in total sugars and polyphenols and had low levels of dietary fiber (P > 0.05 for all parameters). Commercial orange juice contained less vitamin C (P = 0.035) and folate (P = 0.002) than home-made juice (15% and 27% less, respectively), probably owing to the vitamin degradation that may occur during industrial production (e.g., during pasteurization) and storage of commercial orange juice. The observed differences were of relatively small magnitude overall, however, and within the expected ranges for vitamin loss due to pasteurization and storage at ambient temperature. Indeed, commercial orange juice contained 85% of the vitamin C concentration measured in home-made juice, showing that vitamin C was well preserved in commercial juice. Another study with a larger number of samples would be needed to confirm these observations.

Relationships between Fruit Acceptability and Health-Case of Seven Pomegranate (<i>Punica granatum</i>L.) Juices

The objective of this study was to evaluate acceptability and instrumental measurements (titratable acidity, total soluble sugar, total phenolic, flavonoids, anthocyanins, and condensed tannin contents as well as antioxidant capacity) of seven Tunisian pomegranate cultivars to relate fruit acceptability and beneficial health. Seventy one participants were asked to complete a questionnaire and to indicate their level of acceptance, on a nine point-hedonic scale, for fruit size, sweetness, bitterness, juice color and juice overall acceptability. Taste and aril color were the main criteria to select Pomegranate. Significant differences occurred for all the acceptability tests. Titratable acidity determines the taste and important inter-specific variability in the phenolic contents as well as for the antioxidant capacities was noticed. Anthocyanin and condensed tannin were contributing to the organoleptic properties while bitterness acceptability was negatively correlated to the antioxidant capacity. Also, a relationship was found between the fruit size acceptability and the antioxidant capacity.

Quality Control of Juices Produced in Democratic Republic of Congo and Marketed in Lubumbashi

The consumption of juice has increased sharply in recent years in Lubumbashi. The objective of this study was to determine the standards applicable to the types of juice for domestic consumption in Lubumbashi. A descriptive cross-sectional study on quality control (QC) of ten brands of juice selected from around thirty listed on the Lubumbashi markets focused on the determination of different physico-chemical and microbiological parameters. Physical analysis of the juices was carried out in the laboratory of the Congolese Office of Control (OCC) in February 2019. It appears that five samples, or 25%, have a density lower than the ISO 9001 standard. All the samples have a Brix Degree in accordance with French standards applicable by the Congolese control office. The chemical analysis shows that 4 samples, or 20%, have a pH 4, therefore higher than the prescribed standards. As for the titratable acidity and the formaldehyde index, all the samples have values within normal limits. On the other hand, the glucose level of all the samples is abnormally high (≥40 g/L). The sucrose level of 50% of the samples is normal (≥80 g/L). Microbiological analysis revealed that certain juices were without preservatives and harbored aerobic mesophilic germs (10%), lactic bacteria (20%) yeasts and molds (10%). It is urgent that the public authorities bring all the producers to respect the standards in order to protect the health of the populations.

Survival and Growth Characteristics of <i>Escherichia coli </i>O157:H7 in Pomegranate-Carrot and Pomegranate-Apple Blend Juices

Unpasteurized fruit juice has been implicated in outbreaks of Escherichia coli O157:H7 (E. coli O157:H7). Meanwhile, certain fruit, such as pomegranate, contains antimicrobial components. The objective of this study was to investigate the survival and growth characteristics of E. coli O157:H7 on pomegranate juice in laboratory medium and in pomegranate-carrot and pomegranate-apple blend juices at different concentrations. Single strain of E. coli O157:H7 (E0019, H1730, and Cider) was inoculated into brain heart infusion (BHI) broth or a mixture of three strains was inoculated into the blended juices containing pomegranate juice. Our results showed that the addition of pomegranate juice inhibited the growth of tested E. coli O157:H7 in both laboratory medium and blended juices.The antimicrobial activity increased with increased concentrations of pomegranate juice (P < 0.001) and incubation times.The bacterial population was reduced by at least 2 log CFU/ml in BHI broth and juice blend samples in the presence of 20% and 40% Pomegranate juice respectively. Sensory evaluations performed using a 9 point hedonic scale showed significant satisfaction on using 40% pomegranate juice blend with carrot and apple juices. Our study suggests that pomegranate juice could be used as a natural antimicrobial in different food systems including juices to inhibit the growth of E. coli O157:H7.

Analysis of Certain Fruit Juices Using Microwave Techniques

This paper discusses a novel method of analyzing the dielectric properties of juices at various frequencies of microwave band. The measurements were performed using a rectangular cavity with the perturbation technique at the S-band of microwave frequency with fresh juices made instantly from the fruits as well as collected from the packed fruit juices available in the market with the normal added preservatives in order to keep the increase of the shelf life. From the results, it is observed in the certain dielectric properties, the fresh juices samples and packed juices samples were varying and also varying over a period of time. This measurement method is simple and quick and can be used over a range of juices. These results prove a new method of determining the quality control of juices using microwave principles.

Physicochemical and Microbiological Properties of Bissap (Hibiscus sabdariffa) and Ginger (Zingiber officinale (L) Rose) Juices Sold in the Western Part of Abidjan (Côte d’Ivoire)

Juices made from the calyx of Hibiscus sabdariffa (Malvaceae), commonly called Bissap, and the rhizome of Zingiber officinale (Zingiberaceae), known as Gnamankoudji, are widely consumed in C&ocirc;te d'Ivoire. The artisanal preparation of these juices often makes their quality problematic. The aim of this study is to determine some physicochemical and microbiological properties of these drinks sold in the city of Abidjan. To do this, samples of Bissap and Gnamankoudji juices were collected near schools in the Mamie Adjoua (Yopougon) and Abobodoumé (Attécoubé) districts. Physico-chemical and microbiological analyses were performed on these collected samples. The results show that the Bissap and Gnamankoudji juices have an acid pH (2.47 and 3.71), a low protein content (0.78% and 2.11%) and a high water content (80.13% and 85.21%), respectively. The reducing sugar content ranged from 1.20% to 3.34%, with high total sugar (695 mg/mL and 812 mg/mL), low ash (0.70 ± 0.07;0.91 ± 0.01). On the other hand, these juices contain variable concentrations of minerals from one site to another (magnesium, calcium, phosphorus, potassium and iron). Potassium is the most abundant mineral element, followed by phosphorus and magnesium. Moreover, it is observed that the Gnamankoudji juices contain vitamin C (4.67 to 5.58 mg/100mL), contrary to the Bissap juice. The microbiological analysis indicates the presence of aerobic mesophilic germs (AMG) but a total absence of pathogenic germs in all juices. The important presence of nutrients and the total absence of pathogenic germs in these drinks justify their regular consumption by the population.

Early detection of pancreatic cancer

The diagnosis of pancreatic cancer associates an appalling significance.Detection of preinvasive stage of pancreatic cancer will ameliorate the survival of this deadly disease.Premalignant lesions such as Intraductal Papillary Mucinous Neoplasms or Mucinous Cystic Neoplasms of the pancreas are detectable on imaging exams and this permits their management prior their invasive development.Pancreatic intraepithelial neoplasms(PanIN)are the most frequent precursors of pancreatic adenocarcinoma(PDAC),and its particular type PanIN high-grade represents the malignant non-invasive form of PDAC.Unfortunately,PanINs are not detectable on radiologic exams.Nevertheless,they can associate indirect imaging signs which would rise the diagnostic suspicion.When this suspicion is established,the patient will be enrolled in a follow-up strategy that includes performing of blood test and serial imaging test such as computed tomography or magnetic resonance imaging,which will cost in the best-case scenario a burden of healthcare systems,and potential mortality in the worst-case scenario when the patient underwent resection surgery,worthless when there is no moderate or high grade dysplasia in the final histopathology.This issue will be avoid having at its disposal a diagnostic technique capable of detecting high-grade PanIN lesions,such is the cytology of pancreatic juice obtained by nasopancreatic intubation.Herein,we review the possibility of detection of early malignant lesions before they become invasive PADC.

Nutraceutical Potentiality of Fruits of Red Variety of Pseudospondias microcarpa (A. Rich) Engl.

The red fruits of Pseudospondias microcarpa (A. Rich) Engl. are widely consumed by the populations of northern Congo for their sweet and tangy flavor as well as for their characteristic smell. The objective of this study was to show the food potential of the fruits of this plant for their valorization. Organic solvent extracts were prepared and subjected to phytochemical screening to determine the nutrients and phytonutrients of this fruit. Raw juice was extracted by trituration without adding water and subjected to physicochemical and biochemical analyses in order to determine its quality and its antiradical activity. The raw juice obtained is moderately acidic (pH 3.28), very cloudy and colored (turbidity of 1019 NTU). It has a dry matter content of 3.771% ± 0.013% reflecting the 70% dominance of water in the weight of the fruit and the presence of dissolved organic matter in its juice. Energy nutrients (sugars, amino acids), carotenoids, coumarins, tannins, flavonoids, terpenes and sterols have been highlighted as nutrients with therapeutic potential commonly called phytonutrients of this fruit. The juice presented a dominance in polyphenols (134.8500 ± 0.0023 mg gallic acid/100 g) than in carotenoids (5.100 ± 0.010 mg carotene/100 g), high levels of mineral macroelements (calcium: 3570.00 ± 2.05 mg and potassium: 4576.00 ± 9.49 mg) and trace elements (copper: 11.13 ± 0.10 mg, iron: 3.02 ± 0.03 mg and zinc: 2.57 ± 0.08 mg). These compounds exhibited good antioxidant activity. The presence of these nutrients and phytonutrients in these fruits is interesting for the proper functioning of certain organs and the prevention of certain diseases. This fruit is therefore an energizing and functional food that can compete with conventional fruits whose juices are marketed.

Study on Compound Stabilizer Formulation for Mango Juice with Skin

[Objectives]The effects of stabilizers such as sodium carboxymethyl cellulose,pectin,sodium alginate and xanthan gum on the stability of mango juice with skin were discussed using mango as the raw material.[Methods]The formula and stability of mango beverage with skin were studied using mango juice with skin as the raw material.Four stabilizers,including pectin,sodium alginate and sodium carboxymethyl cellulose,were added to improve the stability of the juice.Based on single factor experiments and a response surface experiment,the stability model of mango juice was established to determine the best compound stabilizer.[Results]According to an orthogonal experiment on the stability of mango juice with skin,the optimum technical parameters were as follows:sodium carboxymethyl cellulose 0.20%,xanthan gum 0.08%,sodium alginate 0.18%,and pectin 0.14%,with which the optimal suspension stability was 69.12%.The optimum technical parameters from the response surface experiment were as follows:sodium carboxymethyl cellulose 0.199%,pectin 0.1185%,sodium alginate 0.163%,and xanthan gum 0.077%,with which the suspension stability was 70.32%.It was found that the stability of mango juice with skin obtained by the response surface experiment was better than that by the orthogonal experiment,and the order of factors affecting the stability of mango was sodium alginate(C)>sodium carboxymethyl cellulose(A)>pectin(D)>xanthan gum(B).[Conclusions]The formula of compound stabilizer for mango juice was optimized by the orthogonal experiment and the response surface method,providing a theoretical basis for the actual production of mango juice with skin.

Characterization of the key aroma compounds in four varieties of pomegranate juice by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O),odor activity value(OAV),aroma recombination,and omission tests

P omegranate(Punica granatum L.)has attracted considerable attention in world markets due to its valuable nutrients and highly appreciated sensory properties.The aroma profiles of 4 varieties of pomegranate juice,including Dahongtian(DP),Jingpitian(JP),Luyudan(LP),and Tianhonngdan(TP),were investigated via gas chromatography-mass spectrometry(GC-MS)and gas chromatography-olfactometry(GC-O)analyses.A total of 43 volatile compounds were identified by using GC-MS.Among these compounds,16 were considered as potential aroma-active compounds as detected by GC-O.These compounds belonged to the classes of terpinenes,alcohols,and aldehydes.Eleven volatile compounds were defined as the main contributors to the overall aroma of pomegranate juice due to their high odor activity values(OAVs≥1).Aroma recombination and omission tests confirmed thatβ-myrcene,1-hexanol,and(Z)-3-hexen-1-ol were the key aroma compounds,and limonene,1-octen-3-ol,linalool,and hexanal were important aroma-active compounds in DP samples.

木星系探测与JUICE任务概述

北京时间2023年4月14日,JUICE探测器的成功发射标志着木星系探测进入黄金时代,后续将重点针对冰卫星的宜居性进行全面探测。除了木星系探测共有的辐射环境恶劣、能源供给困难等技术难点,JUICE任务还有研制难度大、科学载荷多、任务周期长、轨道设计复杂等特点。本文对目前木星系探测发展形势及JUICE任务要点进行了梳理,总结了关键科学问题及技术挑战,对我国未来木星系探测具有借鉴意义。

Intraprocedural gastric juice analysis as compared to rapid urease test for real-time detection of Helicobacter pylori

BACKGROUND Endofaster is an innovative technology that can be combined with upper gastrointestinal endoscopy(UGE)to perform gastric juice analysis and real-time detection of Helicobacter pylori(H.pylori).AIM To assess the diagnostic performance of this technology and its impact on the management of H.pylori in the real-life clinical setting.METHODS Patients undergoing routine UGE were prospectively recruited.Biopsies were taken to assess gastric histology according to the updated Sydney system and for rapid urease test(RUT).Gastric juice sampling and analysis was performed using the Endofaster,and the diagnosis of H.pylori was based on real-time ammonium measurements.Histological detection of H.pylori served as the diagnostic gold standard for comparing Endofaster-based H.pylori diagnosis with RUT-based H.pylori detection.RESULTS A total of 198 patients were prospectively enrolled in an H.pylori diagnostic study by Endofasterbased gastric juice analysis(EGJA)during the UGE.Biopsies for RUT and histological assessment were performed on 161 patients(82 men and 79 women,mean age 54.8±19.2 years).H.pylori infection was detected by histology in 47(29.2%)patients.Overall,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value(NPV)for H.pylori diagnosis by EGJA were 91.5%,93.0%,92.6%,84.3%,and 96.4%,respectively.In patients on treatment with proton pump inhibitors,diagnostic sensitivity was reduced by 27.3%,while specificity and NPV were unaffected.EGJA and RUT were comparable in diagnostic performance and highly concordant in H.pylori detection(κ-value=0.85).CONCLUSION Endofaster allows for rapid and highly accurate detection of H.pylori during gastroscopy.This may guide taking additional biopsies for antibiotic susceptibility testing during the same procedure and then selecting an individually tailored eradication regimen.

Bio-capped and green synthesis of ZnO/g-C_(3)N_(4) nanocomposites and its improved antibiotic and photocatalytic activities: An exceptional approach towards environmental remediation

In this research study, we have synthesized the bio-capped ZnO/g-C_(3)N_(4) nanocomposites by employing lemon juice(Citrus limon) as a stabilizer and mediator. Fruitfully, lemon juice which contains various acidic functional groups and citric acid has the capability to block the surface of g-C_(3)N_(4) from chemical reactivity and activated the surface of g-C_(3)N_(4) for various reactions. Consequently, the agglomeration behavior and controlled shape of g-C_(3)N_(4) has also been achieved. Our experimental results i.e. XRD,TEM, HRTEM, PL, FS, XPS, and PEC have confirmed that the lemon juice mediated and green g-C_(3)N_(4)(L-CN) have good performances and remarkable visible light photocatalytic activities as compared to the chemically synthesized g-C_(3)N_(4)(CN). Furthermore, the small surface area and low charge separation of g-C_(3)N_(4) is upgraded by coupling with Zn O nanoparticles. It is proved that the coupling of Zn O worked as a facilitator and photoelectron modulator to enhance the charge separation of g-C_(3)N_(4). Compared to pristine lemon-mediated green g-C_(3)N_(4)(L-CN), the most active sample 5Zn O/L-CN showed ~ 5-fold improvement in activities for ciprofloxacin(CIP) and methylene blue(MB) degradation. More specifically,the mineralization process and degradation pathways, and the mineralization process of ciprofloxacin(CIP) and methylene blue(MB) are suggested. Finally, our present novel research work will provide new access to synthesize the eco-friendly and bio-caped green g-C_(3)N_(4)nanomaterials and their employment for pollutants degradation and environmental purification.

Appraisal of Improvement in Physiological and Metabolic Processes by Exogenously Applied Natural and Synthetic Ascorbic Acid in Okra(Abelmoschus esculentus L.)Fruit Subjected to Water Deficit Stress

To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective shot-gun approach.Ascorbic acid(AsA)is a potential organic substance,which widely occurs in plants,and is considered to be an effective antioxidant to counteract reactive oxygen species(ROS).Thus,a pot experiment was performed to assess the relative mitigating impacts of synthetic AsA and naturally occurring AsA in the form of lemon juice(LJ)and orange juice(OJ)on two cultivars of okra(Abelmoschus esculentus L.)namely Sabz Pari and Bhindi Sanwali under varying water deficit conditions.After 30 days of seed germination,okra seedlings were subjected to different irrigation regimes,i.e.,water deficit stress[(65%and 50%F.C.)and control conditions(100%F.C.)].Different levels of AsA[control(no spray),14 mg L^(−1)LJ,24 mg L^(−1)OJ and 150 mg L^(−1)AsA]obtained from different sources were applied as a foliar spray to control and water-stressed plants.Drought stress prominently reduced plant growth and yield attributes of the okra cultivars.Water-deficit conditions(65%and 50%F.C.)substantially decreased the fruit chlorophyll(a,b)pigments and the activity of superoxide dismutase(SOD)enzyme,while an increase was observed in the contents of fruit’s hydrogen peroxide(H_(2)O_(2)),malondialdehyde(MDA),total phenolics,total soluble sugars,AsA,and total soluble proteins.Drought stress also increased the activities of antioxidant enzymes like peroxidase(POD)and catalase(CAT).However,plant growth and yield attributes,fruit chlorophyll pigments,total phenolics,total soluble sugars,total free amino acids,total soluble proteins,AsA,GB,H_(2)O_(2),and the activities of antioxidant enzymes(POD and CAT)were increased by the AsA exogenous treatment in both okra cultivars under water deficit and control conditions.Overall,LJ and OJ were more effective than the synthetic AsA in upregulating the physiological and metabolic processes of okra plants.So,cost-effective as well as multi-nutrient natural sources of AsA could be suggested for alleviating the harmful effects of water deficit stress on plants.