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Antioxidant Properties and Yield of Wood Ear Mushroom, Auricularia polytricha (Agaricomycetes), Cultivated on Rubberwood Sawdust

Teoh HL, Ahmad IS, Johari NMK, Aminudin N, Abdullah N

Int J Med Mushrooms, 2018;20(4):369-380.
PMID: 29953397 DOI: 10.1615/IntJMedMushrooms.2018025986

Mushroom cultivation has become an important component of agriculture, providing food and contributing to the global economy. It uses vertical space and addresses issues of food quality, health improvement, and environmental sustainability. Auricularia mushrooms are popular ingredients in traditional Chinese cuisine. The objective of this study was to determine yield and evaluate radical scavenging capacity of A. polytricha cultivated on rubberwood sawdust on a large scale; we measured total phenolic content; DPPH, hydroxyl, superoxide anion, and peroxyl radical scavenging; and reducing power. Cultivation on rubberwood sawdust produces an average of 4 harvests per bag and a biological efficiency of 80-82%. The antioxidant capacity investigations revealed that the ethyl acetate fraction was the most potent radical scavenger in all assays except that for superoxide anions, whereas the aqueous fraction exhibited mild to moderate antioxidant capacity in scavenging the various radicals. Artificial cultivation of A. polytricha on rubberwood sawdust yields many sporophores with potent antioxidant capacity.

Matched MeSH terms: Peroxides/metabolism
Improvement of enzymatic bioxylitol production from sawdust hemicellulose: optimization of parameters

Rafiqul ISM, Mimi Sakinah AM, Zularisam AW

Prep Biochem Biotechnol, 2021;51(10):1060-1070.
PMID: 33724897 DOI: 10.1080/10826068.2021.1897840

Enzymatic production of bioxylitol from lignocellulosic biomass (LCB) provides a promising alternative to both chemical and fermentative routes. This study aimed to assess the impacts of catalytic variables on bioxylitol production from wood sawdust using xylose reductase (XR) enzyme and to optimize the bioprocess. Enzyme-based xylitol production was carried out in batch cultivation under various experimental conditions to obtain maximum xylitol yield and productivity. The response surface methodology (RSM) was followed to fine-tune the most significant variables such as reaction time, temperature, and pH, which influence the synthesis of bioxylitol from sawdust hydrolysate and to optimize them. The optimum time, temperature, and pH became were 12.25 h, 35 °C, and 6.5, respectively, with initial xylose 18.8 g/L, NADPH 2.83 g/L, XR 0.027 U/mg, and agitation 100 rpm. The maximum xylitol production was attained at 16.28 g/L with a yield and productivity of 86.6% (w/w) and 1.33 g/L·h, respectively. Optimization of catalytic parameters using sequential strategies resulted in 1.55-fold improvement in overall xylitol production. This study explores a novel strategy for using sawdust hemicellulose in bioxylitol production by enzyme technology.

Matched MeSH terms: Peroxides/metabolism*
Endometriosis and infertility: the role of exogenous lipid peroxides in the peritoneal fluid

Arumugam K, Dip YC

Fertil Steril, 1995 Jan;63(1):198-9.
PMID: 7805914

OBJECTIVE: To determine if lipid peroxides were raised in the pelvic peritoneal fluid of patients with endometriosis.
DESIGN: Control study involving patients with and without endometriosis.
METHODS: The lipid peroxide (malondialdehyde) levels in the pelvic PF of 12 patients with moderate-to severe endometriosis, 15 patients with minimal-mild endometriosis and 13 patients with normal pelvises were compared.
RESULTS: The level of lipid peroxides were not affected by the presence nor the severity of endometriosis.
CONCLUSION: Accelerated lipid peroxidation does not appear to play a role in the causal relationship between endometriosis and infertility.

Matched MeSH terms: Lipid Peroxides/metabolism
High levels of oxidative stress in rats infected with Blastocystis hominis

Chandramathi S, Suresh K, Shuba S, Mahmood A, Kuppusamy UR

Parasitology, 2010 Apr;137(4):605-11.
PMID: 19961647 DOI: 10.1017/S0031182009991351

Numerous studies have revealed the presence of oxidative stress in parasitic infections. However, such studies were lacking in the Malaysian population. Previously, we have provided evidence that oxidative stress is elevated in Malaysians infected with intestinal parasites. Stool examinations revealed that about 47.5% of them were infected with the polymorphic protozoa, Blastocystis hominis. However, they were found to have mixed infection with other intestinal parasites.

Matched MeSH terms: Lipid Peroxides/metabolism
Fulltext Colostrum supplementation protects against exercise-induced oxidative stress in skeletal muscle in mice

Appukutty M, Radhakrishnan AK, Ramasamy K, Ramasamy R, Abdul Majeed AB, Noor MI, et al.

BMC Res Notes, 2012;5:649.
PMID: 23173926 DOI: 10.1186/1756-0500-5-649

This study examined the effects of bovine colostrum on exercise -induced modulation of antioxidant parameters in skeletal muscle in mice. Adult male BALB/c mice were randomly divided into four groups (control, colostrum alone, exercise and exercise with colostrum) and each group had three subgroups (day 0, 21 and 42). Colostrum groups of mice were given a daily oral supplement of 50 mg/kg body weight of bovine colostrum and the exercise group of mice were made to exercise on the treadmill for 30 minutes per day. Total antioxidants, lipid hydroperoxides, xanthine oxidase and super oxide dismutase level was assayed from the homogenate of hind limb skeletal muscle.

Matched MeSH terms: Lipid Peroxides/metabolism
alpha-Tocopherol increased nitric oxide synthase activity in blood vessels of spontaneously hypertensive rats

Newaz MA, Nawal NN, Rohaizan CH, Muslim N, Gapor A

Am J Hypertens, 1999 Aug;12(8 Pt 1):839-44.
PMID: 10480480

Antioxidant protection provided by different doses of alpha-tocopherol was compared by determining nitric oxide synthase (NOS) activity in blood vessels of spontaneously hypertensive rats (SHR) treated with alpha-tocopherol. SHR were divided into four groups namely hypertensive control (C), treatment with 17 mg of alpha-tocopherol/kg diet (alpha1), 34 mg of alpha-tocopherol/kg diet (alpha2), and 170 mg of alpha-tocopherol/kg diet (alpha3). Wister Kyoto (WKY) rats were used as normal control (N). Blood pressure were recorded from the tail by physiography every other night for the duration of the study period of 3 months. At the end of the trial, animals were sacrificed. The NOS activity in blood vessels was measured by [3H]arginine radioactive assay and the nitrite concentration in plasma by spectrophotometry at wavelength 554 nm using Greiss reagent. Analysis of data was done using Student's t test and Pearson's correlation. The computer program Statistica was used for all analysis. Results of our study showed that for all the three alpha-tocopherol-treated groups, blood pressure was significantly (P < .001) reduced compared to the hypertensive control and maximum reduction of blood pressure was shown by the dosage of 34 mg of alpha-tocopherol/kg diet (C: 209.56 +/- 8.47 mm Hg; alpha2: 128.83 +/- 17.13 mm Hg). Also, NOS activity in blood vessels of SHR was significantly lower than WKY rats (N: 1.54 +/- 0.26 pmol/mg protein, C: 0.87 +/- 0.23 pmol/mg protein; P < .001). Although alpha-tocopherol in doses of alpha1, alpha2, and alpha3 increased the NOS activity in blood vessels, after treatment only that of alpha2 showed a statistical significance (P < .01). Plasma nitrite concentration was significantly reduced in SHR compared to normal WKY rats (N: 54.62 +/- 2.96 mol/mL, C: 26.24 +/- 2.14 mol/mL; P < .001) and accordingly all three groups showed significant improvement in their respective nitrite level (P < .001). For all groups, NOS activity and nitrite level showed negative correlation with blood pressure. It was significant for NOS activity in hypertensive control (r = -0.735, P = .038), alpha1 (r = -0.833, P = .001), and alpha2 (r = -0.899, P = .000) groups. For plasma nitrite, significant correlation was observed only in group alpha1 (r = -0.673, P = .016) and alpha2 (r = -0.643, P = .024). Only the alpha2 group showed significant positive correlation (r = 0.777, P = .003) between NOS activity and nitrite level. In conclusion it was found that compared to WKY rats, SHR have lower NOS activity in blood vessels, which upon treatment with antioxidant alpha-tocopherol increased the NOS activity and concomitantly reduced the blood pressure. There was correlation of lipid peroxide in blood vessels with NOS and nitric oxide, which implies that free radicals may be involved in the pathogenesis of hypertension.

Matched MeSH terms: Lipid Peroxides/metabolism
Flavonoid quercetin protects against swimming stress-induced changes in oxidative biomarkers in the hypothalamus of rats

Haleagrahara N, Radhakrishnan A, Lee N, Kumar P

Eur J Pharmacol, 2009 Oct 25;621(1-3):46-52.
PMID: 19744476 DOI: 10.1016/j.ejphar.2009.08.030

Quercetin is a bioflavonoid abundant in onions, apples, tea and red wine and one of the most studied flavonoids. Dietary quercetin intake is suggested to be health promoting, but this assumption is mainly based on mechanistic studies performed in vitro. The objective of this study was to investigate the effect of quercetin on stress-induced changes in oxidative biomarkers in the hypothalamus of rats. Adult male Sprague Dawley rats were subjected to forced swimming stress for 45 min daily for 14 days. Effect of quercetin at three different doses (10, 20 and 30 mg/kg body weight) on serum corticosterone and oxidative biomarkers (lipid hydroperoxides, antioxidant enzymes and total antioxidants) was estimated. Swimming stress significantly increased the serum corticosterone and lipid hydroperoxide levels. A significant decrease in total antioxidant levels and super oxide dismutase, glutathione peroxidase and catalase levels was seen in the hypothalamus after stress and treatment with quercetin significantly increased these oxidative parameters and there was a significant decrease in lipid hydroperoxide levels. These data demonstrate that forced swimming stress produced a severe oxidative damage in the hypothalamus and treatment with quercetin markedly attenuated these stress-induced changes. Antioxidant action of quercetin may be beneficial for the prevention and treatment of stress-induced oxidative damage in the brain.

Matched MeSH terms: Lipid Peroxides/metabolism
Neuroprotective effect of bioflavonoid quercetin in 6-hydroxydopamine-induced oxidative stress biomarkers in the rat striatum

Haleagrahara N, Siew CJ, Mitra NK, Kumari M

Neurosci Lett, 2011 Aug 15;500(2):139-43.
PMID: 21704673 DOI: 10.1016/j.neulet.2011.06.021

An increasing large body of research on Parkinson's disease (PD) has focused on the understanding of the mechanisms behind the potential neuro protection offered by antioxidants and iron chelating agents. In this study, the protective effect of the bioflavonoid quercetin on 6-hydroxydopamine (6-OHDA)-induced model of PD was investigated. PD was induced by a single intracisternal injection of 6-hydroxydopamine (300μg) to male Sprague-Dawley rats. Quercetin treatment (30mg/kg body weight) over 14 consecutive days markedly increased the striatal dopamine and antioxidant enzyme levels compared with similar measurements in the group treated with 6-OHDA alone. There was a significant decrease in protein carbonyl content in the striatum compared with that of rats that did not receive quercetin. A significant increase in neuronal survivability was also found with quercetin treatment in rats administered 6-OHDA. In conclusion, treatment with quercetin defended against the oxidative stress in the striatum and reduced the dopaminergic neuronal loss in the rat model of PD.

Matched MeSH terms: Lipid Peroxides/metabolism
Protective effects of Etlingera elatior extract on lead acetate-induced changes in oxidative biomarkers in bone marrow of rats

Haleagrahara N, Jackie T, Chakravarthi S, Rao M, Pasupathi T

Food Chem Toxicol, 2010 Oct;48(10):2688-94.
PMID: 20600524 DOI: 10.1016/j.fct.2010.06.041

Several environmental toxins with toxic effects to the bone marrow have been identified. Pathology associated with lead intoxication is due to the cellular damage mediated by free radicals. In the current study, we examined the effect of Etlingera elatior extract on lead-induced changes in the oxidative biomarkers and histology of bone marrow of rats. Sprague-Dawley rats were exposed to 500 ppm lead acetate in their drinking water for 14 days. E. elatior extract was treated orally (100mg/kg body weight) in combination with, or after lead acetate treatment. The results showed that there was a significant increase in lipid hydroperoxide, protein carbonyl content and a significant decrease in total antioxidants, super oxide dismutase, glutathione peroxidase and glutathione--S-transferase in bone marrow after lead acetate exposure. Treatment with E. elatior decreased lipid hydroperoxides and protein carbonyl contents and significantly increased total antioxidants and antioxidant enzymes. Treatments with E. elatior extract also reduced, lead-induced histopathological damage in bone marrow. In conclusion, these data suggest that E. elatior has a powerful antioxidant effect, and it protects the lead acetate-induced bone marrow oxidative damage in rats.

Matched MeSH terms: Lipid Peroxides/metabolism