Assessment of anti-oxidant activity of plant extracts using microbial test systems

Aims:  To evaluate the anti-oxidant properties of extracts from 20 medicinal herbs growing in western Siberia using microbial test systems and different in vitro methods.
Methods and results:  In vivo anti-oxidant activity of extracts was evaluated for their capacity to protect bacteria, Escherichia coli , against bacteriostatic and bactericidal effects of H₂O₂ and menadione, and action on anti-oxidant gene expression. In vitro anti-oxidant activity has been examined by a number of methods including: the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH^•)-scavenging assay, chelating activity and capacity to protect plasmid DNA against oxidative damage. In addition, total polyphenol content was determined. The extracts of Fragaria vesca , Rosa majalis , Pentaphylloides fruticosa , Alchemilla vulgaris and Pulmonaria mollis possessed the highest levels of anti-oxidant activity in vivo and in vitro . The protective properties were more closely related to the DPPH^• radical-scavenging activity, tannin content and action on anti-oxidant gene expression than to other parameters.
Conclusion:  The extracts of medicinal plants may have anti-oxidant effects on bacteria simultaneously through several different pathways, including direct inhibition of reactive oxygen species, iron chelation and anti-oxidant genes induction.
Significance and Impact of the Study:  Using microbial test systems, we revealed herbs that may be used as potential sources of natural anti-oxidants.     

Extracts of Coleus forskohlii relieves cough and asthma symptoms via modulating inflammation and the extracellular matrix

Asthma is characterized by airway inflammatory infiltration, which leads to airway remodeling and airway hyperreactivity. Coleus forskohlii (CFK) has been used to treat asthma, however, the mechanism involved is not clear. To explore the antiasthma mechanism of extracts of Coleus forskohlii (ECFK), guinea pigs were administered with a spray of phosphoric acid histamine, and rats were sensitized with ovalbumin (OVA). Hematoxylin and eosin staining (H&E) were used to evaluate pathological changes in lung tissue. Enzyme-linked immunosorbent assay (ELISA) was used to determine cytokine levels in serum and bronchoalveolar lavage fluid (BALF). Immunohistochemistry and Western blot analysis were used to assess the expression of intercellular cell adhesion molecule-1 (ICAM-1), phosphorylation of p65 (p-p65), matrix metallopeptidase 9 (MMP-9), and tissue inhibitor of metalloproteinase 1 (TIMP-1). After ECFK treatment, the asthma incubation period of guinea pigs was significantly prolonged. The H&E results showed that the number of eosinophils in the 12.8 g/kg ECFK group was significantly lower when compared with the control group. Moreover, ELISA results demonstrated that interleukin (IL)-4, IL-5, and IL-17 in serum and BALF were significantly decreased, and interferon-γ (IFN-γ) and IL-10 were increased after ECFK treatment. In addition, ECFK treatment resulted in downregulation of ICAM-1, p-p65, MMP-9, and TIMP-1 in lung tissue after being sensitized by OVA. In conclusion, our findings indicated that ECFK significantly alleviated OVA-induced inflammatory infiltration and airway remodeling in asthma. This study laid a theoretical foundation for the clinical use of ECFK.     

四味镇痛中药对内腓肽降解酶作用的实验研究

目的 :研究四味镇痛中药对内腓肽降解酶的作用。方法 :从大鼠的肾脏制备含有内腓肽降解酶的物质 ,建立内腓肽降解酶活性检测模型 ;并用此模型观察四味镇痛中药提取物对内腓肽降解酶特别是对中性内肽酶活性 (NEP2 4 .11)的抑制作用。结果 :(1)钩藤和羌活的水提物显示很强的NEP2 4 11酶抑制作用 ;(2 )无论是有机提取物还是水提物 ,延胡索和川芎对NEP2 4 11的抑制作用都弱于钩藤和羌活 ;(3)钩藤和羌活不仅是氨肽酶和中性内肽酶的双重抑制剂 ,而且是氨肽酶、中性内肽酶和血管紧张素转化酶的三重抑制剂。结论 :四味镇痛中药具有不同的镇痛机制 ,其中 ,钩藤和羌活通过抑制氨肽酶和中性内肽酶而发挥镇痛作用     

高温杀菌对预浸泡豆杆的杀菌效果及品质影响

本研究以预浸泡豆杆为研究对象,研究高温杀菌对预浸泡豆杆中微生物的杀灭效果及其品质的影响,以期获得具有良好感官品质和理化品质的产品。结果表明:当温度≥105℃和时间≥10 min时,样品的菌落总数由初始的8.72×108cfu/g减少到50 cfu/g以内,样品的大肠菌群从1.6×105MPN/g减少到3 MPN/g以内,致病菌均未检出。杀菌温度和杀菌时间对预浸泡豆杆中脂肪含量、pH、弹性影响差异不显著(p>0.05),对水分含量、蛋白质、色差、硬度和咀嚼性影响显著(p<0.05),综合微生物、理化指标、色泽、质构的变化结果,经105℃、15 min和110℃、10 min处理后的预浸泡豆杆既能满足产品卫生要求也可以较好的保留产品原有的品质。     

新疆土著大豆根瘤菌的表型多样性

选用分离自新疆昌吉市郊土壤的大豆根瘤菌61株和参比菌5株,对它们进行唯一碳氮源、抗生素抗性和抗逆性等表型性状分析,结果表明所有菌株在70.1％相似水平上分为快生大豆根瘤菌和慢生大豆根瘤菌2群,其中快生大豆根瘤菌在81.4％相似水平上又分为2个亚群,40株供试的新疆快生大豆根瘤菌与新疆中华根瘤菌聚为一群;7株供试菌聚为一小群,抗逆性强。所有供试快生菌株都与费氏中华根瘤菌相似性低,所以新疆快生大豆根瘤菌可能是与费氏中华根瘤菌相独立的一个种。     

The differential effect of disulfiram on lipoxygenases from Glycine max

A kinetic analysis of the effect of disulfiram on the isoenzymes of lipoxygenase from soybean has been carried out. The compound is an effective inhibitor of type-2 isoenzymes but has no effect on the type-1 isoenzyme under the conditions employed in this study. The inhibitory effect is reversible and therefore does not result from covalent modification of the enzyme. The inhibition is manifest as a prolongation of the lag phase commonly seen in progress curves for lipoxygenases rather than as a reduction of the catalysed rate. A variety of structurally related and unrelated compounds have been investigated to identify the nature of the inhibitory effect. The antioxidant properties of disulfiram account for its ability to inhibit type-2 lipoxygenases. The inhibitory effect of antioxidants on type-2 lipoxygenase is only partly reversed when product hydroperoxide is included in the incubation mixture. These observations support the conclusion that free radical intermediates are integral to the catalytic mechanism of type-2 lipoxygenases.     

Ultrastructural features of soybean somatic cells at the beginning of an organogenic process: toward a new concept*

Summary— Histological and ultrastructural observations of soybean protoplast-derived calli allowed establishment of the very early cellular reorganization that initiates a proliferating process at the beginning of regeneration. These cytological events appeared more clearly in an inductive medium containing 2.4 D. The cells that participate in the somatic regeneration are characterized by special features that chiefly affect the nucleus and mitochondria: an increase of nucleo-cytoplasmic exchange by means of deep invaginations of the nuclear envelope, the occurrence of specific attachments of chromatin dense masses at the bottom of these invaginations and the disappearance of some mitochondria while a great number of them proliferates around the nucleus. All these events are comparable to the cytological reorganization affecting the female gametic lineage that generally occurs during the female gametophytic phase in sexual plant reproduction.     

Development and seed number in indeterminate soybean as affected by timing and duration of exposure to long photoperiods after flowering

BACKGROUND AND AIMS: Long photoperiods from flowering to maturity have been found to delay reproductive development in soybean (Glycine max) and to increase the number of seeds per unit land area. This study was aimed to evaluate whether sensitivity to photoperiod after flowering (a) is quantitatively related to the length of exposure to long days and (b) persists throughout the whole pod-setting period. It was also evaluated whether seed number was related to changes in the duration of post-flowering phenophases. METHODS: Two field experiments were conducted with an indeterminate cultivar of soybean of maturity group V. In expt 1, photoperiods 2 h longer than natural daylength were applied during different numbers of days from the beginning pod stage (R3) onwards, while in expt 2 these photoperiod extensions were imposed during 9 consecutive days starting at different times between R3 and R6 (full seed) stages. KEY RESULTS: There was a quantitative response of development to the number of cycles with a long photoperiod. The exposure to long photoperiods from R3 to R5 (beginning of seed growth) increased the duration of R3-R6 regardless of the timing of exposure. The stages of development comprised in the R3-R6 phase were delayed by current as well as by previous exposure to long days. A positive relationship was found between seed number and the duration of R3-R6, irrespective of the timing and length of exposure to the long photoperiod. CONCLUSIONS: Sensitivity to photoperiod remained high during the reproductive period and was highly and positively coupled with the processes of generation of yield.     

The genus Laggera (Asteraceae) – Ethnobotanical and Ethnopharmacological Information,Chemical Composition as well as Biological Activities of Its Essential Oils and Extracts: A Review

Most species of the genus Laggera are often used in traditional and folk medicines for the treatment of jaundice, inflammation, leukemia, removing phlegm, bronchitis and bacterial diseases. The essential oils obtained from Laggera plants are rich sources of oxygenated monoterpenes and sesquiterpenes. Among oxygenated monoterpenes, aromatic ether 2,5‐dimethoxy‐p‐cymene is the most abundant and dominant compound of many essential oils of the Laggera species. Till today, to the best of our knowledge, chemical compounds of the essential oils and/or extracts of only eight Laggera species were reported from different countries. Thus, this review presents the chemical compositions and biological activities of the essential oils of these plants studied in thirteen countries. In addition, it discusses the reported ethnobotanical and ethnopharmacological information as well as biological activities of the extracts and some of the isolated compounds of Laggera plants species.     

Determination of endogenous fat loss and true total tract digestibility of fat in mink (Neovison vison)

The objective of this study was to determine the endogenous fat loss (EFL) and to calculate true total tract digestibility (TTTD) of fat in mink (Neovison vison) using soybean oil–based diets with different fat levels. In the digestibility assay, four diets with 6.30%, 13.9%, 22.0% and 34.0% fat in dry matter were used. Sixteen adult male mink were distributed in a complete randomised design. The apparent total tract digestibility (ATTD) of dietary fat was 90.8%, 95.9%, 96.9% and 97.8%, respectively. The apparent total digestible fat was linearly related to dietary fat intake (r² = 0.99). The EFL was estimated from the slope of the regression equation and was determined to be 5.09 g/kg DM intake. The TTTD of soybean oil was determined to be 99.3%. Therefore, TTTD values will have negligible impact in feed formulation as they are close to ATTD values with the dietary fat levels normally used for mink.