Throughout the cryopreservation process, plants were exposed to a series of
abiotic stresses such as desiccation and osmotic pressure due to highly concentrated
vitrification solution. Abiotic stress stimulates the production of reactive oxygen species
(ROS) which include hydrogen peroxide, superoxide radicals, and singlet oxygen. Higher
production of ROS may lead to oxidative stress which contributes to the major injuries in
cryopreserved explants. Antioxidant enzymes in plant such as ascorbate peroxidase
(APX) can protect plants from cell damage by scavenging the free radicals. This study was
determined based on APX enzyme activity of Aranda Broga Blue orchid’s protocorm-like
bodies (PLBs) in response to PVS2 (Plant Vitrification Solution 2) cryopreservation
treatments at different stages. PLBs that were precultured at 0.25 M sucrose for 3 days
were subjected to vitrification cryopreservation method. Results obtained showed that the
highest APX activity was achieved at PVS2 cryoprotectant treatment prior liquid nitrogen
(LN) storage. This phenomenon indicating that accumulation of osmotic and dehydrating
stress throughout the cryopreservation treatment resulted in oxidative burst which in turn
leads to higher APX activity in order to control the excess production of ROS. To
conclude, PVS2 treatment was revealed as the most detrimental step throughout
cryopreservation treatment. Thus, this research also suggested that exogenous
antioxidant such as ascorbic acid can be added throughout cryopreservation procedure
especially at PVS2 treatment in the future experiments to aid in regrowth of cryopreserved
explants by reducing oxidative stress.
Vigna sinensis also known as long-podded cowpea or Chinese long bean (Family:Fabaceae) is most widely grown in Southeast Asia. They are a good source of protein, vitamin A, vitamin C, iron, phosphorus, and potassium. The antioxidant potential of crude methanol extract, chloroform, and ethyl acetate soluble fractions of Vigna sinensiswas screened for in- vitro antioxidant activity using total phenolic content, ferric reducing power, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay, ferric thiocyanate (FTC) and thiobarbituric acid (TBA) tests. It was found that ethyl acetate fraction have maximum amount of polyphenolics compounds (2.69 mg/g GAE in concentration 0.5 mg/mL); more effective than methanol and chloroform extract.This fraction also exhibited fairly good antioxidant activity with in both TBA (17.39% mg/g GAE) and FTC (12.65% mg/g GAE) methods.
This study was undertaken to evaluate the potential of fruit waste materials as source of natural antioxidant. The fruit peels including mango, guava and papaya peel were used in this study. The total phenolic content (TPC) was determined by Folin-Ciocalteu assay while antioxidant activities were determined by using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferric thiocynate (FTC) and thiobarbituric acid (TBA) assays. These antioxidant activities were compared to synthetic antioxidants, BHA/BHT combination and ascorbic acid. The results demonstrated that TPC ranged from 3.23 to 15.84 g GAE/100 g extract. Mango peels extract exhibited highest TPC compared to guava peel and papaya peel extract. In the FRAP assay, mango peel extract at 200 ppm, guava peel extract at 400 ppm and papaya peel extract at 1200 ppm, exhibited reducing power comparable to the permissible amount of BHA/BHT at 200 ppm. At concentration of 250 μg/ml, the DPPH radical scavenging activity of extracts and standards decreased significantly in the order of mango peel extract > guava peel extract > BHA/BHT > ascorbic acid > papaya peel extract. For the FTC assay, the antioxidant activity of mango peel extract was significantly higher than ascorbic acid, guava peel and papaya peel extract but lower than BHA/BHT while in the TBA assay, percentage inhibition of BHA/BHT and ascorbic acid were found to be higher than fruit peel extracts. The quantitative analysis for flavonoids showed the presence of catechin, epicatechin and kaempferol in the peel extracts.
This study was conducted to determine radical scavenging activity and vitamin antioxidant composition in red pitaya from organic plantation. For antioxidant vitamins analysis, a reverse-phase high performance liquid chromatography was used and radical scavenging activity of methanolic and water extract were determined using 1,1-diphenyl-2-pircrylhydrazyl assay. Results for radical scavenging activity, red pitaya methanolic extract achieved the highest percentage 70.13% compared with water extract (47.13%). Antioxidant vitamins composition in red pitaya showed that the concentration of vitamin A is 120.13 ± 0.69 μg/100 g freeze-dried sample, vitamin C is 540.27 ± 0.59 μg/100 g fresh samples and vitamin E is 105.67 ± 0.56 μg/100 g freeze-dried samples. This shows that red pitaya may become an alternative and potential source of natural antioxidant.
Efficacy of some Malaysian herbal aqueous extracts, BHA/BHT (synthetic antioxidants) and ascorbic acid in retarding oxidative rancidity was tested with cakes. The development of lipid oxidation products during 15 days at room temperature was evaluated by means of Peroxide Value (PV) and Thiobarbituric acidreactive substances (TBARS) value. The six formulations consists of control sample (cake without addition of antioxidant) (F1), cake added with curry leaves extract (F2), cake incorporated with kesum leaves extract (F3), cake added with tenggek burung leaves extract (F4), cake incorporated with ascorbic acid (F5) and cake added with BHA/BHT (F6). Formulation with the incorporation of tenggek burung leaves extract showed powerful oxidative stability effect compared to the formulations with othe plant extracts and control sample. However, cakes with BHA/BHT showed the strongest oxidative stability throughout the storage period. Therefore, it is suggested that tenggek burung leaves extract can be added into the food system for effectiveness as antioxidant to prolong the shelf life of the product.
There is an increase need and demand to update Malaysian Food Composition Database (FCD) which was last updated in 1997. The current FCD program was designed to expand the quantity and improve the quality of the existing database. The present work was aimed to determine the nutrient content of commercial rice products from three rice varieties classified as raw and processed foods, namely Basmati, Siam, and Fragrant rice. A total of six brands from each type of rice were sampled from a local supermarket within Klang Valley. Analyses were carried out for 27 nutrients that include proximate (Energy, Water, Protein, Fat, Carbohydrate, Total Dietary Fibre, and Ash), minerals (Magnesium, Calcium, Sodium, Iron, Zinc, and Copper), water soluble vitamins (C, B1, B2, B3, B6 and B9), fat soluble vitamins (A and E), total sugar, fatty acids (total saturated fat, total monounsaturated fat and total polyunsaturated), trans fatty acids, and cholesterol. The three rice varieties were found to contain comparable nutrient levels except for vitamin C, B1, A, E and total sugar which were not detected in all samples. The fatty acid (total saturated, total monounsaturated, and total polyunsaturated) as well as trans- fatty acid were detected at very low levels. Cholesterol was not detected in all samples. These findings can be utilised in raising public awareness and assistance to better estimate nutrient contents and intake depending on the varieties of rice.
Although Malaysia is one of the important pineapple fruit producing and exporting country, the production of MD-2 pineapple fruit only started in 2009. Pineapple fruit has been harvested at different ripening stages for different markets. The information on Malaysian grown MD-2 pineapple fruit quality is lacking. Therefore this work was carried out with the aim to determine physicochemical quality, antioxidant compounds and activity of MD-2 pineapple fruit at five ripening stages. Ripening stage affected physicochemical quality of MD-2 pineapple fruit. Soluble solids concentration of MD-2 pineapple fruit increased from 15.41 to 18.02% SSC when fruit ripened from stage 1 to 4 and no significant difference was found in fruit between stage 4 and 5. The ascorbic acid content decreased while total carotenoids content increased as ripening stage advanced. The total phenolic content of both 80% methanol and water extraction solvents increased significantly as fruit ripened from stage 1 to 3 and reduced as fruit ripened to stage 5. The antioxidant activity of MD-2 pineapple fruit as assayed using DPPH, FRAP and ABTS showed similar trend as total phenolic content. These results suggest that ripening stage affect MD-2 pineapple fruit quality and nutritional values.
This study aimed to determine and compare antioxidant components and antioxidant capacity in different parts (skin, pulp, mace and seed) of nutmeg. Freeze dried samples were extracted using 80% methanol, while Folin-Ciocalteu assay was employed to determine total phenolic content, aluminium chloride assay was applied to determine total flavonoid content and ascorbic acid was assessed by titrimetric method. Antioxidant activities were evaluated by ferric reducing antioxidant power and trolox equivalent antioxidant capacity (TEAC) assays. Results revealed that nutmeg seed contained the highest TPC followed by mace, skin and pulp. Similar observation was also found for TFC. The highest ascorbic acid content was found in nutmeg mace, while the lowest was in its pulp. For antioxidant activity, nutmeg seed possessed the highest FRAP and TEAC values, while nutmeg pulp had the lowest as compared to other parts. Phenolic compounds in nutmeg samples have exhibited strong correlation with antioxidant capacity. Therefore, nutmeg is a potential functional food with high antioxidants, especially nutmeg seed. Phenolic compounds in nutmeg samples have exhibited strong correlation with antioxidant capacity. Therefore, nutmeg is a potential functional food with high antioxidants, especially nutmeg seed.
Ascorbic acid or vitamin C is mostly found in natural products such as fruits and vegetables. High performance liquid chromatography (HPLC) method has been developed and validated to compare the ascorbic acid content in Benincasa hispida (Bh) fruit extract with three different extraction solvents; i) 3% metaphosphoric acid, ii) 3% citric acid and iii) distilled water. The compound has been detected and quantified by the use of HPLC coupled with UV-Vis detector. The amount of ascorbic acid detected in Bh fruit extract prepared with different extraction solvents; 3% metaphosphoric acid, 3% citric acid and distilled water were 13.18, 7.91 and 9.42 mg/100g respectively. Total run time was 6 min and the retention time was 2.60 min. Calibration curve was linear with the concentration range 1.00 – 16.00 μg/ml. Limits of detection was 0.24 μg/ml, limit of quantification was 0.81 μg/ml and recovery was 93.52%. The result showed ascorbic acid content is higher in Bh fruit extract with 3% metaphosphoric acid, followed by extract with distilled water and 3% citric acid. Thus, Bh is another novel fruit/ vegetable potentially used as food ingredient as it contains a good source of ascorbic acid that can be good for one’s health.
Roselle (Hibiscus sabdariffa L.) from Malvaceae family is an annual crop with potential for use by many industries including food, animal feed, neutraceutical, cosmeticeutical and pharmaceutical industries. Its origin is not fully known but it is believed to be from West Africa, although the plant is found native from India to Southeast Asia. The calyxes, stems and leaves are acid in flavour. The juice is produced from the calyces, and it is claimed to be a prohealth drink due to its high contents of ascorbic acid, anthocyanins and other antioxidants.
The Malaysian skincare industry is growing rapidly with a vast number of new sunscreens being produced annually. Inadequate skincare regulations and lack of enforcement have resulted in the overrating of sunscreens’ quality. The objectives of this study were to evaluate the efficacy and safety of the local and international sunscreens and to determine the effects of adding concentrated antioxidants into them. Three local and three internationally manufactured sunscreens were tested for the in vitro Ultraviolet A protection factor (UVAPF), Sun Protection Factor (SPF) and photostability. The creams were spread onto roughened polymethylmethacrylate plates where the absorbance was measured using a spectrophotometer before and after two hours of sunlight irradiation. The procedure was repeated combining available concentrated vitamin C and E creams. International sunscreens were found to have more accurate SPF labels (p=0.009) while local sunscreens were found to be more photostable (p=0.003). However, both sunscreens had inadequate UVAPF (p=0.471). Vitamin C enhanced the SPF values (p= 0.04) of both groups of sunscreens while vitamin E enhanced their photostability (p=0.000). Interestingly, combining vitamins C and E rich creams with the sunscreens had no effect on the SPF and UVAPF values as compared to the use of a single vitamin. More importantly, the combination of vitamins decreased the photostability (p=0.002) of sunscreens as compared to the addition of vitamin E alone. In conclusion, photoprotection is best achieved when sunscreens are used together with creams containing either vitamin C or E alone.
Physical training is associated with oxidative stress and improvement in blood antioxidant status. In this study, we investigated the effects of training on plasma malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) as markers of lipid peroxidation, superoxide dismutase (SOD) activity, and ascorbic acid (AA) after a single bout of acute exercise. Twelve healthy, untrained young adult men were recruited for 5 weeks of aerobic training period. They were subjected to a rope-skipping exercise for 20 minutes at the intensity of 65-80% of heart rate reserve, thrice weekly. They also had to perform a single, acute bout of the same exercise protocol prior to and after training period. Venous blood samples were collected at resting condition (BL), immediately (0 h) and 24 hours (24 h) post acute exercise on both single bout sessions. Results showed that the pattern changes of oxidative stress response are quite similar on both acute sessions. The acute bouts of rope-skipping is associated with a significant increased (p = 0.001) in lipid peroxidation markers immediately after cessation of exercise, with a concomitant increases in antioxidant levels, albeit higher when compared to pre-training values (p = 0.001). These changes were followed by a significant decreased (p = 0.001) in all parameters, toward resting values, 24 hours thereafter. The training program seemed to induce a significant increase in MDA and 4-1-INE but also enhanced the antioxidant defense system namely SOD and AA among the untrained subjects.
BACKGROUND: Stress is a normal part of everyday life but chronic stress can lead to a variety of stress-related illnesses including hypertension, anxiety, and depression. In the present investigation, standardized leaf extract of Epipremnumaureum was evaluated for its anti-stress potential.
MATERIALS AND METHODS: For the evaluation of anti-stress activity, groups of mice (n = 6) were subjected to forced swim stress and anoxic stress tolerance test in mice 1h after daily treatment of E.aureumextract. Diazepam (5 mg/kg) was taken as a reference standard. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as noninvasive biomarkers to assess the anti-stress activity and plasma cortisol, blood ascorbic acid, and weight of adrenal were measured. The 24 h urinary excretion of VMA and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The hematological parameters (neutrophils, lymphocytes, and eosinophils) were also determined.
RESULTS: Administration of E.aureumat doses of 400 and 600 mg/kg wasfound to be effective in inhibiting the stress induced urinary biochemical changes in a dose-dependent manner. Treatment with E. aureum extract prevents the rise in blood ascorbic acid and plasma cortisol. Moreover, the extract prevented the increase in weight of adrenal gland also significantly increased the anoxia stress tolerance time. Dose-dependent significant reduction in white blood cell count was observed in anoxic stress tolerance test as compared to stressed group.
CONCLUSION: Hence, the present study provides scientific support for the positiveadaptogenic effect of E. aureum extract.
Scurvy resulting from dietary deficiency of vitamin C is characterized by anaemia, tender limbs swelling and hemorrhagic manifestations such as petechiae and bruises. We report a case of scurvy in a 13 years old boy with cerebral palsy who presented with history of limbs bruising and swelling for 2 months. On examination, he was cachexic and pale with poor dentition and swollen gum. There were extensive bruises and swollen limbs as well. His platelet count and coagulation profile were normal. Limbs X-ray revealed classical scorbutic changes in the long bones. Serum ascorbic acid level was low
Magnetic nanoparticles of Fe₃O₄ were synthesized and characterized using transmission electron microscopy and X-ray diffraction. The Fe₃O₄ nanoparticles were found to have an average diameter of 5.48 ±1.37 nm. An electrochemical biosensor based on immobilized alkaline phosphatase (ALP) and Fe₃O₄ nanoparticles was studied. The amperometric biosensor was based on the reaction of ALP with the substrate ascorbic acid 2-phosphate (AA2P). The incorporation of the Fe₃O₄ nanoparticles together with ALP into a sol gel/chitosan biosensor membrane has led to the enhancement of the biosensor response, with an improved linear response range to the substrate AA2P (5-120 μM) and increased sensitivity. Using the inhibition property of the ALP, the biosensor was applied to the determination of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The use of Fe₃O₄ nanoparticles gives a two-fold improvement in the sensitivity towards 2,4-D, with a linear response range of 0.5-30 μgL-1. Exposure of the biosensor to other toxicants such as heavy metals demonstrated only slight interference from metals such as Hg2+, Cu2+, Ag2+ and Pb2+. The biosensor was shown to be useful for the determination of the herbicide 2, 4-D because good recovery of 95-100 percent was obtained, even though the analysis was performed in water samples with a complex matrix. Furthermore, the results from the analysis of 2,4-D in water samples using the biosensor correlated well with a HPLC method.
In the present study, Karanjin and Pongapin, two important furanoflavone, constituents of Pongamia pinnata were studied in the management of Psoriasis. Presently, we have experimentally studied the free radical quenching property of Karanjin and Pongapin. A modified method was used to estimate the scavenging effect of the Karanjin (the highest activity of 95.60%) and Pongapin (68.05%) compared to the ascorbic acid as standard (11.60%) against nitric oxide. Furthermore, Molecular docking studies were performed using CLC drug discovery workbench software version 3.0 of the studied flavones (Karanjin and Pongapin) with the receptors responsible for psoriasis (viz. IL-17A, IL-17F, IL-23, RORγt, and TLR-7). Docking scores of Karanjin and Pongapin with different studied receptors were found to be comparable to that of Methotrexate, a known drug for treating Psoriasis. Docking results suggest that Karanjin and Pongapin might also help in controlling the disease. Overall, our results indicate that flavones (Karanjin and Pongapin) could be a natural and better alternative in curing psoriasis without any side effects.
Bioactive compounds from plant sources are generally categorized as natural antioxidants with well-known health benefits. The health-promoting characteristics of natural antioxidants include anti-inflammatory, anti-diabetic, and hepatic effects as well as free radical scavenging. Herein, a comprehensive and comparative review are presented about the effects of conventional (thermal and mechanical) and relatively new (non-thermal) processing methods on phytochemicals and discussed the importance of implementing the use of those methods that could be of very helpful retaining the quality of the bioactive compounds in plant-based foods. Plant-based foods rich in phenolics, vitamin C, carotenoids, and other compounds undergo a range of processing operations before they are consumed. Most of these methods involve thermal treatments of fruits, stems, leaves, and roots. These techniques have varying effects on bioactive compounds and their activities, and the magnitude of these effects depends on process parameters such as temperature, time, and the food matrix. Thermal processing can be detrimental to bioactive compounds while nonthermal procedures may not cause significant deterioration of important health-promoting phytochemicals and in some cases can improve their bio-activity and bio-availability. The detrimental effects of conventional processing on the quality of natural antioxidants have been compared to the effects of innovative nonthermal food treatments such as gamma and ultraviolet irradiation, ultraviolet light, pulsed electric fields, and high hydrostatic pressure.
The combination of compounds with different classes (hydrophobic and hydrophilic characters) in single chitosan carrier is a challenge due to the hydrophilicity of chitosan. Utilization of l-ascorbic acid (LAA) and thymoquinone (TQ) compounds as effective antioxidants is marred by poor bioavailability and uptake. Nanoparticles (NPs) solved the problem by functioning as a carrier for them because they have high surface areas for more efficient delivery and uptake by cells. This research, therefore, synthesized chitosan NPs (CNPs) containing LAA and TQ, CNP-LAA-TQ via ionic gelation routes as the preparation is non-toxic. They were characterized using electron microscopy, zetasizer, UV⁻VIS spectrophotometry, and infrared spectroscopy. The optimum CNP-LAA-TQ size produced was 141.5 ± 7.8 nm, with a polydispersity index (PDI) of 0.207 ± 0.013. The encapsulation efficiency of CNP-LAA-TQ was 22.8 ± 3.2% for LAA and 35.6 ± 3.6% for TQ. Combined hydrophilic LAA and hydrophobic TQ proved that a myriad of highly efficacious compounds with poor systemic uptake could be encapsulated together in NP systems to increase their pharmaceutical efficiency, indirectly contributing to the advancement of medical and pharmaceutical sectors.
Potatoes are usually stored under low temperatures for sprout prevention and to ensure their continuous supply. Low
temperature sweetening in potato is the major temperature related disorder being faced by the growers and is also
known to be associated with variety specific storage temperature. The present study aimed at identifying the appropriate
storage temperature for the premium potato variety Lady Rosetta with special reference to the changes in its quality
attributes, that is weight loss, total sugars, starch, ascorbic acids, total phenolic contents, radical scavenging activity,
enzymatic activities and potato chip color. The selected potato variety was stored under different temperature (5, 15 and
25o
C) regimes to identify appropriate storage temperature. Our results showed significant variations in the tested quality
attributes in response to different storage temperatures. Storage at 5o
C maintained tuber dormancy up to 126 days,
however, found associated with increased sugar accumulation (2.32 g/100 g), rapid starch depletion (13.25 g/100 g) and
poor post processing performance (L-value, 52.00). In contrast, potato storage at 15o
C retained lower sugar contents
(1.33 g/100g) and superior chip color (L-value, 59.33) till the end of storage. However, they were found associated with
the increased polyphenol oxidase (38.47 U/g f.w) and peroxidase (15.25 U/100 g f.w) activities as compare to those
potatoes stored at 5o
C during the same storage period. Storage life of potato tubers at 25o
C was significantly reduced
due to dormancy break on 84th day and subsequent starch degradation (15.29 g/100 g) increased sugar accumulation
(1.32 g/100 g) and increased polyphenol oxidase (79.89 U/g f.w) and peroxidase activities (40.69 U/100 g f.w). Our
results showed that potato variety Lady
Limited data regarding methemoglobinemia in pregnancy, particularly secondary to dapsone is available up to date. We report a case of dapsone-induced methemoglobinemia in a pregnant mother with multibacillary leprosy who presented with fever, productive cough and cyanosis of 2 days duration 2 weeks after multidrug therapy was commenced. On examination, she had central cyanosis with low oxygen saturation (SpO2 = 84-88%). Arterial blood gas analysis showed PO2 of 111 mmHg and SO2 of 98 mmHg. Patient was administered 100% oxygen inhalation, but there was no improvement in cyanosis. Vitamin C (1000 mg/day) was prescribed. Dapsone was replaced by ofloxacin 200 mg twice daily. There was a gradual increase in SpO2 level. She delivered a healthy baby. In conclusion, clinicians should be aware of the side effects of dapsone and know how to promptly manage any undesirable events. Ofloxacin is a safe and feasible alternative in replacement of dapsone in pregnancy.