TOXICITY AND ANTIBACTERIAL EFFECT OF MACE OF MYRISTICA FRAGRANS USED IN MOROCCAN GASTRONOMY: BIOCHEMICAL AND HISTOLOGICAL IMPACT

The aril of the plant Myristica fragrans is one of the most broadly used spices in Moroccan gastronomy. This research demonstrated its antimicrobial activity against both gram-positive and gram-negative bacterial species. Likewise, its toxicity was investigated on Swiss albino mice. Mice were treated orally with 0.003 and 0.3 mg/day during 7 days. Plasmatic markers and antioxidant defense systems were assessed and histological alterations evaluated. Our results showed a significant increase in creatine phosphokinase level. The microscopic evaluation showed that mace induces morphological perturbation in mice's liver. The results also showed an inhibitory effect of glyceraldehyde 3-phosphate dehydrogenase and an important increase in the level of thiobarbituric acid reactive substances, succinate dehydrogenase activities and no change in catalase activities. All of these results show that M. fragrans at 0.3 mg/g in mice affects energy metabolism and oxidative stress.

PRACTICAL APPLICATIONS

Mace can be used as a natural antioxidant and preservative in the food industry to increase the shelf life of foodstuffs.     

ANTIOXIDANT POTENTIAL OF ORAL FEEDING OF CYNODON DACTYLON EXTRACT ON DIABETES-INDUCED OXIDATIVE STRESS

The present study is an extension of our previous research work and it deals with the scientific evaluation of antioxidant potential of the aqueous extract of Cynodon dactylon on diabetes-induced oxidative stress of diabetic rats. The most effective dose of 500 mg/kg of extract was given orally to diabetic rats for 30 days. Different oxidative stress parameters were analyzed in various tissues of control and treated diabetic rats. The observed elevated level of LPO comes down significantly ( P <  0.05), and decreased activities of antioxidant enzymes such as CAT, SOD, GPx and GST got increased ( P <  0.05) significantly in diabetic rats on extract treatment. The flavonoids present in the aqueous extract of this plant might be responsible for its marked antioxidant efficacy at tissue level in STZ-induced diabetic rats.

PRACTICAL APPLICATIONS

The Cynodon dactylon has been shown to possess varied medicinal properties. The aqueous extract of the rhizome is used as anti-inflammatory, diuretic, antiemetic, antidiabetic and blood-purifying agent. Recently, it has been reported by our research group that the extract of C. dactylon has hypoglycemic as well as antidiabetic potential. The present communication is an endeavor in the direction of evaluating its in vivo antioxidant effect in STZ-induced diabetic rats so that it can be used as a value-added agent for managing diabetes as well as oxidative stress associated with it.     

OXIDATIVE STRESS AND ANTIOXIDANT SYSTEMS IN TOMATO FRUITS DURING STORAGE

Tomato varieties ARTH‐3 (long shelf‐life; 14–15 days) and Sel‐7 (short shelf‐life; 5–7 days), harvested at color turning stage, were stored in open trays at 10, 25 and 35C and sampled at two day intervals until complete deterioration. Variety ARTH‐3 could be stored at all the temperatures for ten days, while Sel‐7 could tolerate 35C only for four days. However, at 10 and 25C, it could be stored for six days. In both varieties, lipoxygenase (LOX) activity, malondialdehyde (MDA) value and H₂O₂ content increased during storage. Increase in storage temperature further enhanced the activity of LOX, and also increased MDA value and H₂O₂ content. Sel‐7 had higher values for these parameters than ARTH‐3. Activities of enzymes responsible for scavenging reactive oxygen species (ROS) viz., superoxide dismutase, peroxidase, ascorbate peroxidase, glutathione reductase and catalase decreased continuously during storage. With increase in temperature, the activities of these enzymes further decreased significantly in both varieties. Sel‐7 had significantly lower activities of ROS scavenging enzymes than ARTH‐3 throughout the storage period. These results suggest that fruits stored at higher temperature are subjected to severe oxidative damage leading to extensive membrane damage and loss of tissue structure.     

鳙鱼内脏蛋白质和脂肪的分析

探讨鳙鱼内脏的利用途径和价值,分析了鳙鱼内脏各部分的组成.其中内脏含有丰富的蛋白质和脂肪.鳙鱼内脏蛋白质中含有8种必需氧基酸且含量丰富,尤其肝脏和肠蛋白质中赖氨酸含量分别高达12.05 g/100 g蛋白质和25.51 g/100g蛋白质.鳙鱼内脏中含脂肪组织17.52 g/100 g,鱼脂肪的碘植为105.21 I2/100 g.这些结果表明鳙鱼内脏具有较好的可利用前景.     

豆渣脱腥脱色制取膳食纤维

试验通过正交组合确定了将豆渣经过脱腥、脱色等一系列处理制取膳食纤维的最佳工艺条件。     

EFFECT OF PROCESSING ON CONSTITUENTS AND OXIDATIVE STABILITY OF MARINE OILS

Changes in the contents of neutral and polar lipids, α-tocopherol, free fatty acids and color of seal blubber oil (SBO) and cod liver oil (CLO) during different processing steps of alkali-refining, bleaching, and deodorization were monitored. Refined, bleached and deodorized (RBD) SBO and CLO contained approximately 39 and 71% less polar lipids than their crude counterparts, respectively. There was also a reduction of 98.5 and 97.4% in the corresponding free fatty acids content of RBD-SBO and RBD-CLO. The content of α-tocopherol in both oils decreased during processing, especially at the bleaching and deodorization steps. The oxidative stability of SBO and CLO following each processing step was determined by measuring peroxide and 2-thiobarbituric acid reactive substances values. Results so obtained indicated that crude oils were most stable while their refined-bleached counterparts were least stable, perhaps due to the removal of endogenous natural antioxidants such as α-tocopherol during processing of oils.     

OXIDATIVE STABILITY OF EXTRACTED SESAME OIL FROM RAW AND PROCESSED SEEDS

Sesame oil was prepared from raw and processed seeds. Processing conditions were roasting at 200C for 20 min, steaming at 100C for 20 min, roasting at 200C for 15 min + steaming for 7 min and microwaving at 2450 MHz for 15 min. Oxidative stability of the resultant hexane-extracted oils was determined during storage under Schaal oven test conditions at 65C for up to 35 days. Methods employed included determination of fatty acid composition, iodine value (IV), peroxide value (PV), conjugated dienes (CD), para-ansidine value (p-AV) and 2-thiobarbituric acid (TBA) value. The oils from raw and roasted-steamed seeds had better oxidative stability than other processed oils. In addition, nuclear magnetic resonance (NMR) spectroscopy was used to evaluate the extent of oxidation of sesame oils by measuring the relative changes of aliphatic to olefinic (R_ao) and aliphatic to diallylmethylene (R_ad) protons of the oils. A gradual increase in the (R_ao) and (R_ad) values was observed during the entire storage period.     

洋葱中黄酮苷的提取及抗氧化稳定性研究

探讨洋葱中黄酮苷的提取工艺,以及pH值、温度和光照条件对洋葱黄酮苷抗氧化稳定性的影响.结果表明:洋葱用40倍75%的丙酮溶液,在60℃条件下提取1 h为最佳提取方法;洋葱中黄酮苷在微酸性条件下的抗氧化性质比较稳定;在70 ℃以上条件下保存1 h基本失去抗氧化活性;洋葱中黄酮苷对光线敏感.     

MICROBIAL ENZYMES AND THEIR EFFECTS ON EXTRACT RECOVERIES FROM UNMALTED ADJUNCTS

Radial diffusion tests were used to detect β-glucan-, starch-, protein-, pentosan- and triglyceride-degrading enzyme activities in a variety of commercial enzyme preparations. Some implications of the presence of unexpected enzymes in particular preparations are discussed. A series of laboratory mashes were made with grists of milled barley, extruded barley, and extruded wheat, using various enzyme additions and temperature-time programmes. In addition a limited number of experiments were made with pale ale barley malt, and wheat flour pellets. Extract yields varied from acceptable to outstandingly good. The most intensive mashing system, with enzyme supplementation, increased the extract yield of an all-malt mash by 3·9% relative to the control mashing programme. Some worts were evaluated for Total Soluble Nitrogen (T.S.N.), Free Amino Nitrogen (F.A.N.) and viscosity. Slow wort-filtration rates occurred in some mashes although the viscosities of the worts from these mashes were low. This problem did not occur in any of the samples intensively mashed over a 5 h period. The results apparently exclude the possibility that a simple, reliable technique for estimating the extract yields of adjuncts could be devised, using these enzyme preparations.