1,3-Diferuloyl-sn-glycerol from the biocatalytic transesterification of ethyl 4-hydroxy-3-methoxy cinnamic acid (ethyl ferulate) and soybean oil

Enhancement of the hydrophilic feruloyl glycerol synthesis using A-35 as a catalyst and its functional characteristics

Feruloyl glycerol (FG) is the hydrophilic ester of ferulic acid (FA), which has a high solubility in water and a strong ability to resist ultraviolet (UV) radiation. In this work, several solid acids were used as novel economical catalysts and FA was used as a cheap substrate for FG preparation. The effects of reaction variables on the esterification of FA with glycerol were investigated and optimized by response surface methodology (RSM). Results showed that a cheap solid acid cation exchange resin A-35 showed the best performance for esterification. The reaction conditions were optimized by RSM as follows: 15 : 1 (glycerol/FA) substrate molar ratio and 14% catalyst loading at 90 °C for 7 h. The maximum FG yield (98.50 ± 0.58%) was achieved under the optimized conditions. The activation energy of the esterification was 53.71 kJ mol^-1. The results of UV absorbance showed that FG had good anti-UV activity and photostability, which can be used as a potential antioxidant and UV absorber in food and sunscreen products.

Sparganii Rhizoma: A review of traditional clinical application, processing, phytochemistry, pharmacology, and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Sparganii Rhizoma (SR), a traditional Chinese medicine (TCM), is the rhizome of Sparganium stoloniferum Buch.-Ham. mainly distributed in East Asia. It has been used for eliminating blood stasis, promoting the flow of Qi, removing the retention of undigested food and relieving pain in China for hundreds of years.

AIM OF THE REVIEW

This review summarizes comprehensive information in traditional clinical application, processing, phytochemistry, pharmacology, quality control and toxicity of SR, in exploring future scientific and therapeutic potentials.

MATERIALS AND METHODS

Pertinent information was systematically collected from several electronic scientific databases (e.g., Web of Science, PubMed, China Knowledge Resource Integrated, Springer, Elsevier, ScienceDirect, and Google Scholar), PhD and MS dissertations, and classic Chinese medical books.

RESULTS

SR is a gynecological drug which is often used to treat dysmenorrhea, mass in the abdomen, amenorrhea due to blood stasis, and abdominal distension in TCM. Two kinds of processed products of SR are included in Chinese Pharmacopoeia, which have better pharmacological effects than the crude herb. Approximately 180 compounds have been identified from SR, including phenylpropanoids, flavonoids, anthraquinones, organic acids, alkaloids, steroids, volatile oils, diarylheptanes, etc. The crude extracts and isolated components of SR have been reported to have anti-tumor, antithrombotic, estrogen antagonistic , anti-inflammatory, analgesic, antioxidant, anti organ fibrosis and other pharmacological activities. SR also has reproductive toxicity.

CONCLUSIONS

As an important TCM, SR has been demonstrated by modern pharmacological researches to have significant bioactivities, especially on anti-tumor, antithrombotic, and estrogen antagonistic activities. These activities provide prospects for the development of new drugs and therapeutics for future applications. Nevertheless, quality control and evaluation, in-depth pharmacological mechanism, and toxicological effect of SR require further detailed research.

Rapid Raman spectroscopic determination of 1-feruloyl-sn-glycerol and 1,3-diferuloyl-sn-glycerol

Ferulic acid and its derivatives are important natural products found throughout the plant kingdom and are of special interest due to their health benefits. 1-Feruloyl-sn-glycerol (FG) and 1,3-diferuloyl-sn-glycerol (F₂G) are two common bioproducts of ferulic acid that co-occur in nature and during the biocatalytic production of feruloylated lipids. In this paper, we report a comprehensive characterization of FG and F₂G using Raman and UV spectroscopies and theoretical density functional theory calculations at the B3LYP/6-311+G** level. UV spectroscopy produced spectra for FG and F₂G with similar peak shape, but difference intensities. The vibrational frequency calculations aided in the assignment of the Raman bands. The Raman analysis demonstrates that Raman spectroscopy is a rapid label free method to clearly distinguish between FG and F₂G.

Enzymatic Synthesis and Flash Chromatography Separation of 1,3-Diferuloyl-sn-Glycerol and 1-Feruloyl-sn-Glycerol

Ethyl ferulate was transesterified with Enova Oil (a soy-based vegetable oil containing 80-85% diacylglycerol) using Novozym 435 at 60 °C. The resultant feruloylated vegetable oil reaction product produced a precipitate (96.4 g, 4.02 wt%) after 7 d of standing at room temperature. Preliminary characterization of the precipitate identified the natural phenylpropenoids 1,3-diferuloyl-sn-glycerol (F2G) and 1-feruloyl-sn-glycerol (FG) as the major components. A flash chromatography method was developed and optimized (e.g., mass of sample load, flow rate, binary solvent gradient slope, and separation run length) using a binary gradient of hexane and acetone mobile phase and silica gel stationary phase to separate and isolate F2G and FG. The optimized parameters afforded F2G (1.188 ± 0.052 g, 39.6 ± 1.7%) and FG (0.313 ± 0.038 g, 10.4 ± 1.3%) from 3.0 g of the transesterification precipitate, n = 10 trials. Overall, all flash chromatography separations combined, F2G (39.1 g, 40.6%) and FG (9.4 g, 9.8%) were isolated in a combined yield of 48.5 g (51.4%), relative to the 96.4 g of transesterification precipitate collected. The optimized flash chromatography method was a necessary improvement over previously reported preparative HPLC and column chromatography methods used to purify milligram to low gram quantities of F2G and FG to be able to process ~100 g of material in a timely, efficient manner.

Hydrophilic Glyceryl Ferulates Preparation Catalyzed by Free Lipase B from Candida antartica

Ferulic acid (FA), 4-hydroxyl-3-methoxy-2-benzylacrylic acid, has antioxidant, anticancer and ultraviolet absorption activities. However, the low hydrophilicity of FA has limited its application. Glyceryl ferulate (FG), which is an all-natural hydrophilic derivative of FA, can be used as an antioxidant and UV filter in food and cosmetic formulations. However, the applications of FG in these fields are limited due to its low content in nature. In this work, free liquid lipase was firstly used as a catalyst for FG preparation. Several different free liquid lipases (Candida antartica lipase-B, Candida antartica lipase-A, Thermomyces lanuginosus (Lipozyme TL 100L)) were screened and compared. The effects of the transesterification parameters (time, temperature, enzyme load and substrate ratio) were optimized and evaluated by response surface methodology. A reaction thermodynamic investigation was also performed. The results showed that, among the tested free lipases, the maximum FG yield (84.8±1.5%) was achieved using free Candida antartica lipase-B. Under the optimized conditions (an atmospheric system, an enzyme load of 11.1% and a 20:1 molar ratio of glycerol to EF at 70°C for 39.5 h), the FG yield and EF conversion were 84.8±1.5% and 95.7±1.2%, respectively. The activation energies of FG formation and EF conversion were 56.4 and 58.0kJ/mol, respectively.

Bioactive chemical constituents from the root bark of Morus australis

Two new pyranoflavonoids, morustralins A (1) and B (2), a new natural benzene derivative, one benzenoid (Z)-1-hydroxy-4-(2-nitroethenyl)benzene (3), and thirty known compounds were isolated and characterized from the root bark of Morus australis. The structures of the new compounds were established from spectroscopic and spectrometric analyses. Ten isolates (1-10) were examined for inhibitory effects on adenosine diphosphate (ADP)-, arachidonic acid (AA)-, and platelet-aggregating factor (PAF)-induced platelet aggregation. Among the tested compounds, compound 3 displayed the most significant inhibition of ADP- and AA-induced platelet aggregation with IC₅₀ values of 9.76±5.54 and 9.81±2.7μM, respectively. In addition, eight purified compounds (3-10) were examined for inhibition of nitric oxide (NO) production in RAW 264.7 cells and six compounds (3-8) displayed significant inhibitory effects with IC₅₀ values ranging from 2.1±0.3 to 6.3±0.6μM.

Enzymatic synthesis of bioactive compounds with high potential for cosmeceutical application

Cosmeceuticals are cosmetic products containing biologically active ingredients purporting to offer a pharmaceutical therapeutic benefit. The active ingredients can be extracted and purified from natural sources (botanicals, herbal extracts, or animals) but can also be obtained biotechnologically by fermentation and cell cultures or by enzymatic synthesis and modification of natural compounds. A cosmeceutical ingredient should possess an attractive property such as anti-oxidant, anti-inflammatory, skin whitening, anti-aging, anti-wrinkling, or photoprotective activity, among others. During the past years, there has been an increased interest on the enzymatic synthesis of bioactive esters and glycosides based on (trans)esterification, (trans)glycosylation, or oxidation reactions. Natural bioactive compounds with exceptional theurapeutic properties and low toxicity may offer a new insight into the design and development of potent and beneficial cosmetics. This review gives an overview of the enzymatic modifications which are performed currently for the synthesis of products with attractive properties for the cosmeceutical industry.

Biotransformation: a green and efficient way of antioxidant synthesis

Antioxidant compounds play a vital role in human physiology. They prevent the oxidation of biomolecules by scavenging free radicals produced during physiochemical processes and/or as a result of several pathological states. A balance between the reactive oxygen species (free radicals) and antioxidants is essential for proper physiological conditions. Excessive free radicals cause oxidative stress which can lead to several human diseases. Therefore, synthesis of the effective antioxidants is crucial in managing the oxidative stress. Biotransformation has evolved as an effective technique for the production of structurally diverse molecules with a wide range of biological activities. This methodology surpasses the conventional chemical synthesis due to the fact that enzymes, being specific in nature, catalyze reactions affording products with excellent regio- and stereoselectivities. Structural transformation of various classes of compounds such as alkaloids, steroids, flavonoids, and terpenes has been carried out through this technique. Several bioactive molecules, especially those having antioxidant potential have also been synthesized by using different biotransformation techniques and enzymes. Hydroxylated, glycosylated, and acylated derivatives of phenols, flavonoids, cinnamates, and other molecules have proven abilities as potential antioxidants. A critical review of the biotransformation of these compounds into potent antioxidant metabolites is presented here.

Enhanced transesterification of ethyl ferulate with glycerol for preparing glyceryl diferulate using a lipase in ionic liquids as reaction medium

Glyceryl diferulate (DFG) is a water-soluble ester of ferulic acid. A novel ionic liquid (IL) system for enzymatic transesterification of ethyl ferulate (EF) with glycerol to produce DFG was developed. Of three ILs with different anions (BF4 (-), PF6 (-) and TF2N(-)) and cations (BDMIM, OMIM, HMIM, BMIM, and EMIM), EMIMTF2N proved the best using a commercial lipase. It had a significant protective effect against thermal inactivation of the enzyme. High EF conversion (~100 %) and DFG yield (45 %) were achieved using 45 mg enzyme/ml; temperature, 70 °C; reaction time, 12 h.