Clinical,pathologic, and toxicologic characterization of Salvia reflexa (lance-leaf sage) poisoning in cattle fed contaminated hay

Salvia reflexa (lance-leaf sage)-contaminated alfalfa hay was fed to ~500 mixed-breed beef cattle. Within hours of exposure, nearly half of the cattle developed lethargy, anorexia, depression, and recumbency, followed by bellowing, colic, and death. Even though the uneaten contaminated hay was removed the first day, nearly 100 animals died within the first 48 h. Three of these cattle were examined postmortem, and tissues and hay samples were collected for microscopic and chemical analysis. Several days later, a smaller number of the clinically poisoned cattle developed neurologic disease with aberrant behavior, aggression, icterus, blindness, exhaustion, and death. A total of 165 cattle were fatally poisoned. Poisoned cattle had swollen, dark, mottled livers that had a prominent nutmeg-like lobular pattern on cut section. Histologically, there was severe centrilobular-to-panlobular hepatic necrosis with marked hepatocellular swelling, degeneration, and necrosis. The surviving cattle developed liver disease characterized by altered serum biochemical analyses and microscopic hepatocellular degeneration and necrosis. In subsequent biopsies and analysis, these lesions resolved within 6–7 mo. After confirming toxicity of the hay in cattle, goats, and mice, followed by a mouse bioassay–guided chemical fractionation process, Salvia reflexa was identified as the contaminant in the hay responsible for the hepatotoxicity. S. reflexa has not been reported previously to cause fatal hepatotoxicity in livestock in North America, to our knowledge.     

具有广阔发展前景的几种云南天然香料

叙述了云南省天然香料资源开发利用简况及生产现状，提出了发展香料产业区域布局的设想。重点论述了香荚兰、肉桂、薄荷的国内外生产动向及在云南的发展现状和前景。     

薰衣草薄荷叶非精油组分清除自由基作用的研究

【目的】为薰衣草薄荷叶非精油组分的医疗、保健和营养等功能提供理论依据。【方法】分别采用水、甲醇-水、乙酸乙酯和乙醇提取法对薰衣草薄荷叶非精油组分进行了提取,并分别采用超氧阴离子自由基(O2.-)、羟自由基(.OH)、过氧亚硝基(ONOO-)化学发光体系和.OH氧化损伤DNA的化学发光体系以及二苯代苦味肼基自由基(DPPH.)比色体系,对得到的4种提取物抗氧化能力进行比较。【结果】薰衣草薄荷叶非精油组分的有效成分主要存在于极性和弱极性溶剂提取物中。4种薰衣草薄荷叶非精油组分提取物不仅能够直接有效地清除O2.-、.OH、ONOO-和DPPH.,而且能够有效地抑制和延缓.OH对DNA的氧化损伤。【结论】薰衣草薄荷叶非精油组分是一种有效的、多功能的天然抗氧化剂和自由基清除剂,具良好的应用前景。     

砂姜黑土薄荷施肥技术研究

研究了砂姜黑土薄荷施肥技术，结果表明，在薄荷分枝期追施N138kg／hm^2时，基肥施N易使薄荷前期旺长，过早封行，通风透气差，会造成收获期薄荷大量落叶，进而影响薄荷油产量。K肥能显著提高薄荷产量，在低K用量时，氯化钾和硫酸钾增产效果相近，但在高钾用量时，则硫酸钾增产效果明显好于氯化钾，表明高用量的氯对薄荷油有不利的影响，从降低成本和提高产量两方面考虑，硫酸钾和氯化钾配合施用可获得较理想的效果。施用P肥对薄荷生长和产量提高效果不大，且P肥过高会影响薄荷的生长。     

4种薄荷种子萌发对干旱与低温的响应

以柠檬薄荷(Mentha citrata)、胡椒薄荷(Mentha piperita)、美国薄荷(Monarda didyma)、猫薄荷(Nepeta racemosa)为供试材料,采用PEG-6000模拟干旱,研究干旱与低温的交互作用对4种薄荷种子萌发及幼苗生长的影响。结果表明,干旱与低温对这4种薄荷种子的萌发及幼苗生长均有显著影响(P0.05),30%的PEG-6000和8~10℃的低温处理严重抑制了这4种薄荷种子的萌发及生长,柠檬薄荷种子发芽表现出较强的抗旱性。4种薄荷种子在22~24℃处理下发芽率最高,胚芽、胚根和叶的生长表现出差异性,柠檬薄荷在12~14℃时胚根和叶的生长良好。干旱和低温的交互作用对4种薄荷种子的萌发及生长影响显著(P0.001)。     

Effect of Chromium and Lead on Yield,Chemical Composition of Essential Oil,and Accumulation of Heavy Metals of Mint Species

A pot culture experiment was conducted to investigate the effect of increasing levels (30.0 and 60.0 mg kg^?1 soil) of chromium and lead on the yield, chemical composition of essential oil, and phytoaccumulation of heavy metals of three mint species (Mentha arvensis, M. piperita, and M. citrata). The fresh herbage yield of M. arvensis was not significantly affected by the application of chromium and lead, but its essential oil yield was significantly decreased by the application of chromium and lead as compared to the control. The fresh herbage, root yield, and essential oil yield of M. piperita were significantly increased and those of M. citrata were decreased by the increase in the levels of chromium and lead applications. The levels of α-pinene, β-pinene, sabinene, β-myrcene, limonene, menthone, and isomenthone in M. arvensis and M. piperita oil and of sabinene, pinene, and linalyl acetate in M. citrata oil were considerably affected by the application of chromium and lead to soils as compared to control plants. The concentrations of chromium in shoots and roots of mint species significantly increased as the levels of chromium in soil increased. The increases in the levels of lead in soil enhanced the concentrations of lead in the shoots and roots of mint species as compared to the control. The accumulations of chromium and lead were greater in the roots than in the shoots in all the three species of mint. Mentha piperita was found to be the most suitable crop for cultivation in the chromium- and lead-contaminated soils, followed by M. arvensis and M. citrata.     

立枯丝核菌AG-1 IB引起白菜、薄荷、莴苣叶腐病的研究*

 云南省西双版纳地区白菜、薄荷、莴苣叶腐病频繁发生,从有叶腐症状的病害组织中分离到立枯丝核菌（Rhizoctonia solani）菌株。根据培养性状、菌丝直径、细胞核数目、融合群反应、5.8 s rDNA片段序列分析及致病性测定,结果表明引起白菜、薄荷、莴苣叶腐病的病原菌为立枯丝核菌AG-1 IB菌丝融合群。     

镉低积累药用植物盆栽及大田筛选试验

目的 比较不同植物对重金属镉积累能力差异,筛选出镉低积累药用植物种类。方法 以夏枯草、益母草、薄荷为供试材料,通过盆栽和大田试验,采用原子吸收光谱法测定植物中镉的含量。结果 三种植物积累镉的能力存在差异,益母草 > 薄荷 > 夏枯草。益母草在镉污染土壤中其地上部分镉含量随土壤镉浓度增高而增高,而生长不受影响,属于抗性植物。在镉胁迫下,薄荷、夏枯草生长受到抑制,植物中镉含量较低,且随土壤镉浓度增加植物中镉含量变化较小,属于镉低积累植物。结论 益母草为镉高积累植物,且生长不受影响,可以作为富集植物治理镉污染;薄荷中镉主要积累在地下部分,而其以地上部分入药,夏枯草为镉低积累植物,两者均为可在镉污染地区种植的药用植物。     

基于鱼鳞明胶的可食性保鲜膜对金枪鱼肉的保鲜作用研究

为分析不同复合保鲜膜处理对金枪鱼的保鲜效果,以鱼鳞明胶为主料,添加桔子/柠檬精油和薄荷制备可食性保鲜膜,用于金枪鱼肉的冷藏保鲜,检测冷藏过程中金枪鱼肉的TVB-N值、pH值、菌落总数、肌红蛋白与高铁肌红蛋白含量、a^*值、TBA值的变化,并对金枪鱼的品质进行感官评价分析。结果表明,鱼鳞明胶膜中添加薄荷、桔子精油和柠檬精油均能不同程度地抑制金枪鱼肉中的微生物繁殖,减缓TVB-N值、TBA值和高铁肌红蛋白含量的升高,抑制鱼肉色泽的衰变,且薄荷与桔子/柠檬精油的复合有协同增效保鲜金枪鱼肉的作用。明胶膜中复合2%浓度的桔子/柠檬精油对金枪鱼肉风味略有覆盖,低浓度桔子/柠檬精油(1%)有优化金枪鱼鱼肉气味的作用,且以柠檬精油的效果更优,1%薄荷-1%桔子精油-鱼鳞明胶复合膜和1%薄荷-1%柠檬精油-鱼鳞明胶复合膜保鲜处理的金枪鱼肉的货架期可分别延长至 7 d 和8 d。本研究结果为制备高品质水产品可食性保鲜膜材料提供了理论依据和技术支持。     

Yield and Resource Use Optimization in Late Transplanted Mint (Mentha arvensis) under Subtropical Conditions

A field experiment was conducted during 1994 and 1995 at Lucknow (26.5°N, 80.5°E, 120 m above mean sea level) to optimize planting density and fertilizer-N application for high essential oil yield of late transplanted mint ( Mentha arvensis ). The treatments studied were 2.5, 2.0 and 1.66 × 10⁵ mint seedlings ha⁻¹ and 0, 80, 160 and 240 kg N ha⁻¹. Under 3 months delayed planting conditions using 2-month-old seedlings, the high planting density of 2.5 × 10⁵ plants ha⁻¹combined with 160 kg N ha⁻¹ gave significantly higher herb and essential oil yields compared with those of lower planting densities (2 and 1.66 × 10⁵ plants ha⁻¹) and all other rates of N application. It is demonstrated that a transplanted mini crop, yielding essential oil at a level of 164 kg ha⁻¹, is feasible after the harvest of rabi cereal, oil seed or legume crops in the north Indian plains.