New oligosaccharides prepared by acid hydrolysis of the polysaccharides from Nerium indicum Mill and their anti-angiogenesis activities

Structural characterization and chondroprotective activity evaluation of four novel polysaccharides purified from Anoectochilus zhejiangensis on transgenic fluorescent zebrafish

Anoectochilus zhejiangensis (AZJ) exhibits notable anti-inflammatory and anti-swelling properties, making it a potential therapeutic agent for osteoarthritis. However, the specific component responsible for its anti-osteoarthritis effects remains unidentified. In this study, four novel polysaccharides were purified from Anoectochilus zhejiangensis (i.e., AZJP-1a, AZJP-2a, AZJP-2b, and AZJP-2c) through DEAE-cellulose 52 and Sephadex G-200 column chromatographic separation. Their structural and conformational characteristics were comprehensively analyzed. AZJP-1a and AZJP-2a owned high molecular weights of 387 kDa and 947 kDa, while AZJP-2b and AZJP-2c were comparatively lower at 3.989 kDa and 3.045 kDa. The polysaccharides contained predominantly β-glycosidic linkages over α-glycosidic linkages. AZJP-1a primarily consists of mannose, while AZJP-2a and AZJP-2b are rich in glucose, galactose, and arabinose, and AZJP-2c is mainly composed of glucose. Chondroprotective effects of these polysaccharides were evaluated using fluorescence imaging in transgenic fluorescent zebrafish (Tg Col2a1a: eGFP), with all four polysaccharides demonstrating significant cartilage repair activity, surpassing that of the positive control drug alendronate. Among them, AZJP-2c exhibited the most potent effect. The observed variations in their biological activities are likely attributed to differences in their structural compositions.

A toxic shrub turned therapeutic: The dichotomy of Nerium oleander bioactivities

Nerium oleander L. is a medicinal plant, used for the treatment of cancers and hyperglycemia across the world, especially in Indian sub-continent, Turkey, Morocco, and China. Although clinical studies supporting its pharmacological effects remain critically underexplored, accidental and intentional consumption of any part of the plant causes fatal toxicity in animals and humans. While the polyphenolic fraction of oleander leaves has been attributed to its pre-clinical pharmacological activities, the presence of diverse cardiac glycosides (especially oleandrin) causes apoptosis to cancer cells in vitro and results in clinical signs of oleander poisoning. Thus, the dual pharmacological and toxicological role of oleander is a perplexing dichotomy in phytotherapy. The current investigative review, therefore, intended to analyze the intrinsic and extrinsic factors that likely contribute to this conundrum. Especially by focusing on gut microbial diversity, abundance, and metabolic functions, oleander-associated pharmacological and toxicological studies have been critically analyzed to define the dual effects of oleander. Electronic databases were extensively screened for relevant research articles (including pre-clinical and clinical) related to oleander bioactivities and toxicity. Taxonomic preference was given to the plant N. oleander L. and synonymous plants as per 'The World Flora Online' database (WCSP record #135196). Discussion on yellow oleander (Cascabela thevetia (L.) Lippold) has intentionally been avoided since it is a different plant. The review indicates that the gut microbiota likely plays a key role in differentially modulating the pharmacological and toxicological effects of oleander. Other factors identified influencing the oleander bioactivities include dose and mode of treatment, cardiac glycoside pharmacokinetics, host-endogenous glycosides, plant material processing and phytochemical extraction methods, plant genotypic variations, environmental effects on the phytochemical quality and quantity, gene expression variations, host dietary patterns and co-morbidity, etc. The arguments proposed are also relevant to other medicinal plants containing toxic cardiac glycosides.

The Effectively Simultaneous Production of Cello-oligosaccharide and Glucose Mono-decanoate from Lignocellulose by Enzymatic Esterification

Cello-oligosaccharide has drawn an increasing attention as the nutritional ingredients of dietary supplements, whose quality is affected by the concentration of monosaccharide. In the present study, an effective process was developed for the simultaneous production of cello-oligosaccharide and glucose mono-decanoate from lignocellulose by enzymatic esterification. During the process, the excessive glucose in cello-oligosaccharide was converted into glucose mono-decanoate, which is a well-known biodegradable nonionic surfactant. The filter paper was initially used as the model to investigate the feasibility of the process, in which the purity of resultant cello-oligosaccharide was increased from 33.3% to 74.3%, simultaneously producing glucose mono-decanoate with a purity of 92.3%. Further verification of 3 kinds of lignocelluloses (switchgrass, cornstalk, and reed) also indicated a good performance of the process. The present process provided an effective strategy to increase the purity of resultant cello-oligosaccharide with the simultaneous production of high value-added products of sugar monoester. Graphical Abstract Simultaneous production of cello-oligosaccharide and glucose mono-decanoate from lignocellulose.

Preparation of Oligosaccharides by Degradation of Polysaccharides from Chinese Jujube and Its Biological Activity

This study examined the degradation of polysaccharides to oligosaccharides in Chinese jujube fruits. Using a response surface model, the degradation conditions of polysaccharides under acid hydrolysis and enzymatic hydrolysis were optimized in laboratory conditions. A degradation rate of 66.9% was obtained under optimum acid hydrolysis conditions: 0.6 mol/L hydrochloric acid, 3% substrate concentration, and 1 h reaction time. A degradation rate of 41.4% was obtained under optimum enzyme hydrolysis conditions: 4.0 mL cellulose solution (10 mg/mL), 0.3 mL substrate solution (20 mg/mL), 0.7 mL citric acid buffer solution (pH 5), and 7.3 h reaction time. Using the stimulation effect for strain J-4 intestinal probiotic proliferation, the biological activity of oligosaccharides was determined. The results showed that the oligosaccharides from enzyme hydrolysis encouraged intestinal probiotic proliferation.

Emerging concepts in the nutraceutical and functional properties of pectin-A Review

Pectin is a structural heteropolysaccharide found ubiquitously in terrestrial plants. It finds diverse food applications such as that of a gelling agent, stabilizer, and fat replacer. In the pharmaceutical arena, pectin exhibits a number of functions, from decreasing blood fat to combating various types of cancers. This review shows the shift of pectin from its conventional roles to its progressive applications. Insights into the advances in the production of pectin, the role it plays as a nutraceutical, possible prebiotic potential and a delivery vehicle for probiotics, and food applications are highlighted. Bioactive and functional properties of pectin are discussed and how the structural built up defines them, is emphasized. As a biopolymer, the applications of pectin in active packaging are also mentioned.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for 2009-2010

This review is the sixth update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2010. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, arrays and fragmentation are covered in the first part of the review and applications to various structural typed constitutes the remainder. The main groups of compound that are discussed in this section are oligo and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Many of these applications are presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis.

Pharmacological aspects of Nerium indicum Mill: A comprehensive review

Phytomedicine is the oldest medical practice known to man. Since the dawn of mankind, various plant resources are used to cure different diseases and also for a long and healthy life. The ancient knowledge of plant based medicine has transferred from generations to generations and accumulated as ethnopharmacological knowledge among different ethnic groups. India is the spanning bed of traditional phytomedicinal system where Ayurveda was born out of the knowledge of traditional medicine. In various other countries of South-Eastern Asia, South America, and in Arabian countries, still today, a great number of people rely primarily on phytomedicines to cure diseases. In the complementary and alternative medicinal systems, Nerium indicum is one such plant which is famed for its therapeutic efficiency in different diseases globally. In the present time, when the pharmaceutical companies are concentrating more toward the plant based traditional medicines to avoid the side-effects and resistance against synthetic drugs, N. indicum has proved its efficiency in different disease models. Therefore, this review comprehensively covers the medicinal and pharmacological activities of different parts of the plant N. indicum.

Fucanomics and galactanomics: current status in drug discovery, mechanisms of action and role of the well-defined structures

BACKGROUND

With the recent advent of glycomics, many medically relevant glycans have been discovered. Sulfated fucans (SFs) and sulfated galactans (SGs) are one of these classes of glycans with increasing interest to both glycomics and medicine. Besides having very unique structures, some of these molecules exhibit a broad range of pharmacological actions. In certain cases, high levels of effectiveness may be reached when the proper structural requirements are found.

SCOPE OF REVIEW

Here, we cover the fundamental biochemical mechanisms of some of these medicinal properties. We particularly focus on the beneficial activities of SFs and SGs in inflammation, hemostasis, vascular biology, and cancer.

MAJOR CONCLUSIONS

In these clinical systems, intermolecular complexes directly driven by electrostatic interactions of SFs and SGs with P- and L-selectins, chemokines, antithrombin, heparin cofactor II, thrombin, factor Xa, bFGF, and VEGF, overall govern the resultant therapeutic effects. In spite of that, the structural features of SFs and SGs have shown to be essential determinants for formation and stability of those molecular complexes, which consequently account to the differential levels of the biomedical responses.

GENERAL SIGNIFICANCE

Accurate structure-function relationships have mostly been achieved when SFs and SGs of well-defined structures are used for study. Therefore, these types of glycans have become of great usefulness to identify the chemical requirements needed to achieve satisfactory clinical responses.

Structural characterization of a pectic polysaccharide from Nerium indicum flowers

A polysaccharide fraction, J6, was isolated from the hot-water extract of flowers of oleander Nerium indicum Mill., using ethanol precipitation, cetyltrimethylammonium bromide (CTAB) complexing, anion-exchange chromatography and gel permeation chromatography. J6 was found to contain L-rhamnose, L-arabinose, D-galactose, and D-galacturonic acid, in the ratio of 10.1:49.8:30.1:10.0. Its structure was investigated by methylation analysis, periodate oxidation, Smith degradation, partial acid hydrolysis, electrospray ionization mass spectrometry and NMR spectroscopic methods. It was found that J6 is an RG-I type polysaccharide, which contains a rhamnogalacturonan backbone, with various branches attached to O-4 of L-rhamnose. The branches probably involve (1-->4)-beta-D-galactan, branched L-arabino-(1-->3)(1-->6)-beta-D-galactan, and (1-->5)-alpha-L-arabinan. J6 stimulated NO production of macrophage RAW264.7 cells in a preliminary test.