Flavonoids and phenolic acids from sugarcane: Distribution in the plant, changes during processing, and potential benefits to industry and health.

Sugarcane (Saccharum sp.) plants are grown in warmer climates throughout the world and processed to produce sugar as well as other useful byproducts such as molasses and bagasse. Sugarcane is rich in (poly)phenols, but there has been no attempt to critically evaluate the published information based on the use of suitable methodologies. The objective of this review is to evaluate the quantitative and qualitative (poly)phenolic profiles of individual parts of the sugarcane plant and its multiple industrial products, which will help develop new processes and uses for sugarcane (poly)phenols. The quantitative analysis involves the examination of extraction, concentration, and analytical techniques used in each study for each plant part and product. The qualitative analysis indicates the identification of various (poly)phenols throughout the sugarcane processing chain, using only compounds elucidated through robust analytical methodologies such as mass spectrometry or nuclear magnetic resonance. In conclusion, sugarcane (poly)phenols are predominantly flavonoids and phenolic acids. The main flavonoids, derivatives of apigenin, luteolin, and tricin, with a substantial proportion of C-glycosides, are consistently found across all phases of sugarcane processing. The principal phenolic acids reported throughout the process include chlorogenic acids, as well as ferulic and caffeic acids mostly observed after hydrolysis. The derivation of precise quantitative information across publications is impeded by inconsistencies in analytical methodologies. The presence of multiple (poly)phenols with potential benefits for industrial applications and for health suggests sugarcane could be a useful provider of valuable compounds for future use in research and industrial processes.

Antioxidant and Anti-Diabetic Functions of a Polyphenol-Rich Sugarcane Extract.

Objectives: Dysfunctional metabolism of carbohydrates is a fundamental component of many dietary-related disorders. It has been hypothesized that plant extracts containing high levels of antioxidants may have the ability to stabilize carbohydrate regulation. The aim of this study was to assess the effects of a polyphenol-rich sugarcane extract on cellular pathways related to carbohydrate metabolism.Methods: We evaluated the antioxidant activity of a polyphenol-rich sugarcane extract obtained by a patented hydrophobic extract process and its therapeutic potential to regulate carbohydrate metabolism and protect against metabolic disorders such as type 2 diabetes.Results: Quantitative analytical studies support that the polyphenol-rich sugarcane extract has a high concentration of polyphenols and antioxidant compounds. The follow-up cellular studies via Caco-2 cells and dysfunctional ß-cell models suggested that the polyphenol-rich sugarcane extract may help deter glucose and fructose uptake in intestinal cells and restore insulin production in dysfunctional ß-cells-key functions in managing diabetic conditions.Conclusions: These findings suggest that sugarcane polyphenols may modulate cellular mechanism in a manner that is beneficial to health.

Potential contributions of the methodology to the variability of glycaemic index of foods.

Glycaemic index (GI) testing provides a useful point of comparison between carbohydrate sources. For this comparison to be meaningful, the methods used to determine GI values need to be rigorous and consistent between testing events. This requirement has led to increasing standardization of the GI methodology, with an international standard developed in joint consultation with FAO/WHO (ISO 26642:2010) currently the most up to date document. The purpose of this review is to compare the international standard to methods of published studies claiming to have performed a GI test. This analysis revealed that the international standard permits a wide range of choices for researchers when designing a GI testing plan, rather than a single standardized protocol. It has also been revealed that the literature contains significant variation, both between studies and from the international standard for critical aspects of GI testing methodology. The primary areas of variation include; what glucose specification is used, which reference food is used, how much reference food is given, what drink is given during testing, the blood sampling site chosen and what assay and equipment is used to measure blood glucose concentration. For each of these aspects we have explored some of the methodological and physiological implications of these variations. These insights suggest that whilst the international standard has assisted with framing the general parameters of GI testing, further stan-dardization to testing procedures is still required to ensure the continued relevance of the GI to clinical nutrition.

Anti-cancer effects of polyphenol-rich sugarcane extract.

Plant polyphenols have an array of health benefits primarily thought to be related to their high content of anti-oxidants. These are commonly undervalued and knowledge of their biological properties have grown exponentially in the last decade. Polyphenol-rich sugarcane extract (PRSE), a natural extract from sugar cane, is marketed as high in anti-oxidants and polyphenols, but its anti-cancer activity has not been reported previously. We show that, PRSE exerts anti-cancer properties on a range of cancer cells including human (LIM2045) and mouse (MC38, CT26) colon cancer cells lines; human lung cancer (A549), human ovarian cancer (SKOV-3), pro-monocytic human leukemia (U937) and to mouse melanoma (B16) cell lines; whereas no effects were noted on human breast (ZR-75-1) and human colon (HT29) cancer cell lines, as well as to human normal colon epithelial cell line (T4056). Anti-proliferative effects were shown to be mediated via alteration in cytokines, VEGF-1 and NF-κB expression.

In vitro inhibitory activities of sugarcane extract on avian Eimeria sporozoites.

The current in vitro study aimed to investigate the effects of a processed sugarcane extract on the viability of avian Eimeria sporozoites. Treatments were applied to hatched sporozoites: 1) without additives (no-treatment control); 2) with ethanol; 3) with salinomycin; 4) with Polygain™. All treatments were incubated in RPMI media containing live sporozoites at 37 °C for 14 h and then the number of viable sporozoites were counted. Compared to the no-treatment control, Polygain™ decreased (P < 0.001) the counts of E. maxima, E. acervulina, E. bruneti, and E. mitis sporozoites to a level similar to salinomycin (P > 0.05). In conclusion, Polygain™ could be a potential candidate as an anticoccidial agent.

Antioxidant activity and polyphenol composition of sugarcane molasses extract.

The antioxidant activity of sugarcane molasses ethanol extract (ME) and its fraction (ME-RBF) was evaluated using ABTS, ORAC 6.0 and CAA assays and ME-RBF demonstrated 26-fold, 12-fold and 2-fold higher values, respectively than ME. Likewise, total polyphenol and flavonoid concentration in ME-RBF are more than 10-fold higher than ME, that suggested antioxidant activity is correlated with polyphenol composition. Quantitative analysis of 13 polyphenols (chlorogenic acid, caffeic acid, sinapic acid, syringic acid, vanillin, homoorientin, orientin, vitexin, swertisin, diosmin, apigenin, tricin and diosmetin) was carried out by LCMS. MS/MS analysis allowed the tentative identification of seven apigenin-C-glycosides, three methoxyluteolin-C-glycosides and three tricin-O-glycosides some of which have not been reported in sugarcane before to the best of our knowledge. The results demonstrated that sugarcane molasses can be used as potential source of polyphenols that can be beneficial to health.

Polyphenol Rich Sugar Cane Extract Inhibits Bacterial Growth.

Plants that are primarily used as a food source commonly have undervalued biological properties beyond the basic supply of nutrients. One important example of this are the antimicrobial properties of plants. Inclusion of natural and food grade antimicrobial ingredients in recipes to prevent food spoilage and disease transmission, or in cosmetic products to prevent transient and pathogenic bacteria would have world-wide public health implications. A patented natural polyphenol rich sugar cane extract (PRSE), is marketed as a high anti-oxidant and polyphenol ingredient, but its anti-microbial activity has not been reported previously. We determined the anti-bacterial properties of PRSE on common human pathogens relating to a range of diseases including food poisoning, tooth decay, acne and severe skin infections using disc/well diffusion experiments. Our findings indicate that PRSE is an efficient antimicrobial, which could be included at differing dosages to target a range of food borne and environmental pathogens.