Local processing and nutritional composition of indigenous fruits: The case of monkey orange (Strychnos spp.) from Southern Africa

Monkey orange (Strychnos spp.) is a widely distributed fruit species in Southern Africa commonly consumed by the local population. It has potential to improve the nutritional status of rural populations, being a precious food source in areas with periodic shortages, since it is rich in vitamin C, zinc, and iron. To improve the availability of this food outside its production season, processing and preservation techniques used at household level need upgrading as they are unreliable and their effects on nutritional quality are unknown. Based on this review, we recommend better indigenous fruit production as a sustainable solution to malnutrition in rural areas in transition countries.     

Strychnos nux‐vomica an eco‐friendly corrosion inhibitor for mild steel in 1 M sulfuric acid medium

The inhibition efficiency of the extract of Strychnos nux‐vomica for the corrosion of mild steel in 1 M sulfuric acid was investigated using weight loss test (carried out at 303–323 K), electrochemical measurement, and scanning electron microscope (SEM). The results of weight loss studies indicated that the inhibition efficiency increased with inhibitor concentration and the temperature of the system (following Temkin adsorption isotherm). Electrochemical studies proved that the inhibitor acts through mixed mode of inhibition and the inhibitor molecules adsorb on the metal–solution interface. SEM studies supported the adsorption of the inhibitor over the metal surface. The possible active ingredient responsible for the anticorrosion effect is identified as brucine which is isolated and screened for the anticorrosion effect using electrochemical studies and quantum chemical studies. The possible mode of corrosion inhibition of brucine is also derived using FT‐IR studies.     

基于5种生物碱定量分析的马钱子总碱提取工艺优化

首先以乙腈-水为流动相,梯度洗脱,体积流量1 mL/min,柱温35℃,检测波长260 nm,建立同时测定5种马钱子生物碱(士的宁、马钱子碱、士的宁氮氧化物、马钱子碱氮氧化物与番木鳖次碱)含量的反相HPLC法;然后以上述5种生物碱的总量为指标,采用L9(33)正交实验法,对马钱子总碱的回流提取工艺条件(溶剂用量、质量浓度和提取次数)进行优化。结果表明,上述5种马钱子生物碱质量浓度线性范围依次为14.64~468.48、11.625~372.0、0.555~17.76、0.891~28.512μg/mL与2.5~80.0μg/mL,回收率分别为100.3%、101.7%、97.7%、98.8%与99.6%。优化后马钱子总碱的回流提取工艺条件为:加入20倍量体积分数70%的酸性乙醇,回流提取4次,每次1 h。在此提取条件下,马钱子提取物中5种生物碱总质量分数达3.633%。反相HPLC法同时测定5种马钱子生物碱含量的方法简便、准确;以此作为马钱子总碱提取工艺优化的指标更为全面、可靠。     

红栓菌液体发酵条件下马钱子中士的宁和马钱子碱的质量分数变化

在单因素实验条件优化的基础上,采用L16(45)正交试验,以士的宁和马钱子碱的质量分数为主要考察指标,结合菌体生物量,研究不同碳源、氮源、装液量、中药量、菌球数量以及发酵时间对红栓菌发酵马钱子的影响,优化红栓菌液体发酵马钱子的最佳培养基和培养条件。优化工艺为:以麦芽糖为碳源,豆饼粉为氮源,装液量为100mL(250mL的三角瓶),加入0.25g马钱子细粉,接入3个大小均一的红栓菌菌球,28℃摇床培养5d。与发酵空白比较,红栓菌-马钱子发酵液中士的宁和马钱子碱的质量分数总和降低了8.74%,菌体生物量达10.6g/L,增加37.7%,同时马钱子碱氮氧化物和士的宁氮氧化物的质量分数增加。马钱子能促进红栓菌菌体的生长,液体发酵培养可达到降低马钱子中毒性成分质量分数的目的。