Aflatoxin contamination of pods of Indian Cassia senna L. (Caesalpinaceae) before harvest, during drying and in storage: Reasons and possible methods of reduction

The presence of aflatoxins in senna plants was studied in two different areas of India using an HPLC method. Only pods of Cassia senna angustifolia contained aflatoxins: leaves and flowers were free. Damage by insect larvae (Ephestia elutella) led to aflatoxin formation by fungi in the pods. Fruits damaged by other factors can also contain aflatoxins. The occurrence of aflatoxins in senna pods in South India proved to be unevenly distributed. Before harvest, 55% of samples contained less than 2 μg/kg, and 25% more than 10 μg/kg, with a maximum of 255 μg/kg. Controlled sun drying of pods allowed the aflatoxin content to double, while drying in the shade was followed by a four-fold increase. Only a very small fraction of dried senna pods carried the maximum load of aflatoxins. During storage of Indian senna pods, the aflatoxin content usually fell.

The smallest increase of aflatoxins, but still giving rise to unacceptably high levels, was achieved using a solar dryer. The formation of aflatoxins in Indian senna pods could also be reduced by application of NeemAzal T/S^® and even more by a fresh neem leaf water extract, but not to below the desired level of 2 μg/kg. Northern Indian harvest methods, used in South India, resulted in a reduction of aflatoxins, but again not sufficiently, and with a reduced economic output. Sudan senna (C. senna acutifolia), grown in South India, showed resistance to fungal infections and the aflatoxin content was lower than in Indian senna (C. senna angustifolia), in the field and in the laboratory, but growing Sudan senna elsewhere in India was not economical. The consequences of the findings are discussed.     

Organ Specific Differences in Alteration of Aquaporin Expression in Rats Treated with Sennoside A,Senna Anthraquinones and Rhubarb Anthraquinones

Senna and rhubarb are often used as routine laxatives, but there are differences in mechanism of action and potential side effects. Here, we studied metabolites of senna anthraquinones (SAQ), rhubarb anthraquinones (RAQ) and their chemical marker, sennoside A (SA), in a rat diarrhea model. In in vitro biotransformation experiments, SAQ, RAQ and SA were incubated with rat fecal flora solution and the metabolites produced were analyzed using HPLC. In in vivo studies, the same compounds were investigated for purgation induction, with measurement of histopathology and Aqps gene expression in six organs. The results indicated that SAQ and RAQ had similar principal constituents but could be degraded into different metabolites. A similar profile of Aqps down-regulation for all compounds was seen in the colon, suggesting a similar mechanism of action for purgation. However, in the kidneys and livers of the diarrhea-rats, down-regulation of Aqps was found in the RAQ-rats whereas up-regulation of Aqps was seen in the SAQ-rats. Furthermore, the RAQ-rats showed lower Aqp2 protein expression in the kidneys, whilst the SA-rats and SAQ-rats had higher Aqp2 protein expression in the kidneys. This may have implications for side effects of SAQ or RAQ in patients with chronic kidney or liver diseases.     

用于皮肤病的草本抗菌剂产品的开发

织物的抗菌整理可通过形成物理屏障将微生物向穿着者转移降至最低。本研究涉及具有抗菌活性的番泻和羽芒菊的草本提取物。将草本提取物用于棉织物的抗菌整理,并评估整理后的织物对常见的真菌和细菌的抗菌活性。采用AATCC抗菌测试标准对所有经草本提取物整理的样品进行测试,结果表明采用强极性溶剂提取的草本提取物具有更好的抗菌性能。其中乙醇是最佳的萃取溶剂。使用交联剂(明矾)经轧-烘-焙工艺将草本提取物整理到棉织物上。整理后织物的抗菌活性分别采用AATCC-147、AATCC-100和AATCC-30琼脂扩散测试标准进行测试。     

番泻叶萃取物的气相色谱/质谱分析

分别以正己烷和无水乙醇作为溶剂,在微波辐射条件下对番泻叶进行萃取,用气相色谱/质谱联用仪(GC/MS)对萃取物进行了分析。结果表明,角鲨烯是GC/MS可检测的主要成分,正己烷对番泻叶中角鲨烯的萃取具有较好的选择性。     

六堡茶水提物对小鼠腹泻及肠道菌群的影响

目的 探讨六堡茶水提物对番泻叶诱导的小鼠腹泻及肠道菌群的影响。方法 采用六堡茶水提物对小鼠进行20 d的腹泻预防灌胃,从第16 d开始同时给予小鼠番泻叶煎剂诱导小鼠腹泻模型;试验结束时观察各组小鼠行为状态、体重、腹泻率及腹泻指数,检测盲肠内容物pH值及氨态氮含量、粪便肠道菌群数量,分析空肠绒毛形态结构。结果 与正常组相比,模型组小鼠体重显著减轻(P<0.05)、稀便率和腹泻指数均极显著上升(P<0.01),说明番泻叶诱导小鼠腹泻模型构建成功。与模型组相比,六堡茶防治组特别是高剂量组能明显降低了稀便率和腹泻指数(P<0.05),降低了小鼠盲肠内容物pH值及氨态氮含量(P<0.05),增加了小鼠肠道双歧杆菌数量并减少肠球菌数量(P<0.05),提升了小鼠空肠绒毛长度与隐窝深度的比值(V/C值, P<0.05)。结论 六堡茶对小鼠腹泻具有一定防治作用,其止泻作用可能与改善肠道内环境及修复双歧杆菌和肠球菌数量有关。