Bacterial Inoculant and Sucrose Amendments Improve the Growth of Rheum palmatum L. by Reprograming Its Metabolite Composition and Altering Its Soil Microbial Community

Rheum palmatum L. is an important traditional Chinese medicinal herb now in demand worldwide. Recently, the theoretical framework suggested that sucrose triggers colonization of PGPM (plant growth-promoting microbes) in the rhizosphere, but their interactions on the plant remain largely unknown. Here, we applied three concentrations of both Bacillus amyloliquefaciens EZ99 inoculant (1.0 × 10⁵, 1.0 × 10⁶, and 1.0 × 10⁷ colony-forming units (CFU)/mL, denoted as LB, MB, and HB, respectively) and sucrose (0.15, 1.5, and 15 g/L, denoted as LS, MS, and HS, respectively) to investigate their co-effects on R. palmatum in a field experiment. The results showed that LB + MS (1.0 × 10⁵ CFU/mL Bacillus + 1.5 g/L sucrose) and LB + LS (1.0 × 10⁵ CFU/mL Bacillus + 0.15 g/L sucrose) treatments significantly increased root fresh weight (p ≤ 0.05). Metabolite analysis revealed that the treatment LB + LS significantly increased the relative content of major active components in rhubarb, namely anthraquinones and phenolic compounds, by 1.5% and 2.3%. Although high sucrose addition increased the activities of certain soil enzymes, the LB + LS treatment significantly increased total potassium (TK), whereas it decreased available potassium (AK), which facilitated the potassium utilization in rhizosphere soil. Furthermore, rhizosphere microbiomes revealed that fungal diversity was augmented in LB + LS treatment, in which the common causative fungal pathogen Fusarium spp. showed an effective suppression. Additionally, the redundancy analysis and Spearman correlations revealed a positive relationship of Sphingomonas associated with change in potassium bioavailability. Altogether, our findings suggest that the combined application of a bacterial inoculant and sucrose can improve the growth and quality of R. palmatum, and stimulate uptake of plant nutrients that contribute to alter the microbial community for biocontrol potential. Hence, this work not only has broad application prospects across economical plants, but also emphasizes agroecological practices for sustainable agriculture.     

抗果蔬致腐真菌中草药的筛选及有效成分的分析

研究了陈皮、肉桂、丁香、五倍子、艾叶、辛夷、姜黄、川芎、虎仗和蜂胶10种中草药提取物对果蔬致腐真菌扩展青霉和黑曲霉的抑制作用。结果表明：中草药丁香提取物具有较强的抗菌活性，对扩展青霉和黑曲霉的MIC分别为25％和50％；通过GC-MS从丁香挥发油中分离分析出14种化合物，其中丁香酚的相对含量最高，达68％；抑菌试验表明，丁香挥发油MIC中丁香酚的浓度高于丁香酚的MIC。     

Phytochemical Profiles and Antimicrobial Activity of Aromatic Malaysian Herb Extracts against Food‐Borne Pathogenic and Food Spoilage Microorganisms

Preliminary phytochemical and flavonoid compounds of aqueous and ethanolic extracts of 6 aromatic Malaysian herbs were screened and quantified using Reverse‐Phase High Performance Liquid Chromatography (RP‐HPLC). The herbal extracts were tested for their antimicrobial activity against 10 food‐borne pathogenic and food spoilage microorganisms using disk diffusion assay. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)/minimum fungicidal concentration (MFC) of herbal extracts were determined. In the phytochemical screening process, both aqueous and ethanolic extracts of P. hydropiper exhibited presence of all 7 tested phytochemical compounds. Among all herbal extracts, the aqueous P. hydropiper and E. elatior extracts demonstrated the highest antibacterial activity against 7 tested Gram‐positive and Gram‐negative bacteria with diameter ranging from 7.0 to 18.5 mm and 6.5 to 19 mm, respectively. The MIC values for aqueous and ethanolic extracts ranged from 18.75 to 175 mg/mL and 0.391 to 200 mg/mL, respectively while the MBC/MFC values for aqueous and ethanolic extracts ranged from 25 to 200 mg/mL and 3.125 to 50 mg/mL, respectively. Major types of bioactive compounds in aqueous P. hydropiper and E. elatior extracts were identified using RP‐HPLC instrument. Flavonoids found in these plants were epi‐catechin, quercetin, and kaempferol. The ability of aqueous Persicaria hydropiper (L.) H. Gross and Etlingera elatior (Jack) R.M. Sm. extracts to inhibit the growth of bacteria is an indication of its broad spectrum antimicrobial potential. Hence these herbal extracts may be used as natural preservative to improve the safety and shelf‐life of food and pharmaceutical products.     

生物碱生理功能及其提取分离研究进展

生物碱是一类具有生理活性物质,是许多药用植物有效成分之一。该文综述生物碱的分类、提取、分离与鉴别方法及其应用,旨在对生物碱应用提供参考。     

小波变换及其在色谱信号中的应用

介绍了小波变换的基本理论,并对其应用研究进行了评述。小波变换作为信号处理的强有力工具,其已在色谱信号的基线校正、平滑滤噪、谱图压缩、重叠色谱峰解析、中药指纹图特征提取等方面都有成功的应用。最后分析了小波变换在色谱应用研究中现存的问题,并对其未来的发展进行了探讨。     

药食两用中药来源石头饼的工艺优化及质量控制研究

目的 优化药食两用中药来源石头饼工艺,并建立质量控制方法。方法 以感官评价为指标,在单因素考察基础上,采用随机正交试验,对石头饼关键工艺参数进行优化。采用薄层色谱法鉴别、高效液相色谱法对石头饼中黄芪、山茱萸等药味及所含马钱苷进行定性和定量分析。结果 单因素试验结果表明,药食两用中药与小麦粉配比为5%～10%、饼皮厚度为1～2 mm、200℃烘焙10～15 min时,石头饼感官评价得分较高;酵母、棕榈油添加量对石头饼总体感官评价结果影响不大,结合实际,确定酵母添加量为1%,棕榈油涂抹石子进行加工。正交试验结果表明,药食两用药粉配比为10%、饼皮厚度为1～2 mm、200℃烘焙16 min时,所得石头饼感官评价结果良好,工艺稳定可行。薄层色谱及含量测定结果表明,黄芪、山茱萸等药味薄层色谱鉴别方法斑点清晰、阴性无干扰,含量测定方法学考察结果良好,马钱苷平均含量为0.14mg/g。结论 优化的药食两用石头饼工艺稳定可行,建立的定性、定量方法能够有效对该石头饼进行质量控制。     

Influences of freeze- and spray-drying vs. encapsulation with soy and whey proteins on gastrointestinal stability and antioxidant activity of Mediterranean aromatic herbs

The aim of the present research was to study the chemical profile of volatile and non-volatile compounds in freeze- and spray-dried oregano, thyme, sage, and rosemary as well as to study the gastrointestinal stability and the biological activity of the samples after encapsulation using two proteins (soy and whey). Chemical analysis was performed by HS-SPME/GC-MS and HPLC-PDA techniques. The antioxidant activity (FRAP, DPPH and ORAC assays) and HPLC-PDA analyses were performed before and after simulated two-phase digestion process (gastric and duodenal) using human gastrointestinal enzymes. The effect of protein carriers was depended on the plant matrix and the class of compound. Soy protein is useful for the protection of thymol and carvacrol content in thyme and the increase of the antioxidant activity of sage. Whey protein is useful for flavanols stability in all studied herbs before and after the duodenal digestive phase.     

药用植物中残留有机磷农药的定性和定量分析

研究了气相色谱-火焰光度检测器(GC-FPD)定量和气相色谱 离子阱质谱(GC-ITMS)定性法测定药用植物中25种有机磷类农药残留的分析方法。以丙酮为提取溶剂,采用超声波辅助提取药用植物中残留的有机磷农药,经凝胶渗透色谱(GPC)净化,气相色谱-火焰光度检测器定量,气相色谱-离子阱质谱定性,同时检测药用植物中25种有机磷类农药的残留量。添加浓度为0.01～0.04 mg•kg^-1时,回收率为66.58%～111.20%,相对标准偏为0.75%～8.07%。     

Comparative Flavonoids Contents of Selected Herbs and Associations of Their Radical Scavenging Activity with Antiproliferative Actions in V79-4 Cells

ABSTRACT:  To elucidate the health benefit of herbal teas on the cytotoxicity induced by H₂O₂ in V79-4 cells, herbal extracts and its flavonoids were tested using lactate dehydrogenase release and determining intracellular reactive oxygen species generation and antioxidant activity with superoxide radical scavenging assay. Significant decrease in cell viability was observed on V79-4 cells treated with H₂O₂ (1 mM), while herbal extracts and its flavonoids including catechin and epigallocatechin gallate prevented the LDH release from H₂O₂ cytotoxicity. Total catechin contents of green tea (65.6 mg/g of dry matter) were significantly higher than other herbal teas (35.8 to 1.2 mg/g of DM). The relative concentration of the 4 major tea catechins ranked EGCG > EGC > EC > C. Green tea exhibited the lowest IC₅₀ values (2 g fresh herb/100 mL) of superoxide radical scavenging activity among the tested herbal tea, which indicates powerful antioxidant activity in O₂^·− radicals scavenging, followed by black tea, dandelion, hawthorn, rose hip, chamomile.     

Adaptogenic-active components from Kaempferia parviflora rhizomes

Kaempferia parviflora rhizome extracts obtained by maceration with hexane, chloroform, methanol, and ethanol were screened for their adaptogenic activities using swimming tests of mice. The effective adaptogenic extract dose was 500 mg/kg of body weight and was given orally once a day. Crude hexane extract showed significantly shorter mouse immobilisation time than those of the other and control extracts. This crude hexane extract was separated into three fractions by column chromatography. Among these fractions, the fraction rich in terpenoids possessed the highest adaptogenic activity and was comparable to that of the crude ginseng root powder used as a reference control. Therefore, terpenes contained in this fraction could be attributed to the decrease in exhaustion during the swimming of mice. There was no effect on body weight, heart, liver, kidneys, and adrenal glands of the mice. Chemical characterisation of this adaptogenic-active fraction by NMR and GC-MS showed germacene D, β-elemene, α-copaene, and E-caryophyllene as major constituents. Accordingly, these terpenes are considered the adaptogenic agents of K. parviflora rhizomes.