chapter  24
4 Pages

Concluding Remarks

ByGlenn R. Gibson, Marcel B. Roberfroid

The science of prebiotics has come a longway since initiation of the concept in 1995. Concomitantly, new product developments have also moved at a rapid pace. This handbook has attempted to pull together the latest scientific developments, health applications of the concept and human/animal applications. Prebiotics were developed as gut microflora modulatory tools. This has

similarities to the original probiotic aim, and the two approaches have been long associated. However, they are somewhat different in nature, albeit that the intended (health) outputs are, at least partly, similar. The various advantages and disadvantages of both are discussed elsewhere in this book. What is clear is that both, aswell as their combination in a synbiotic, enjoy amajor role in the current functional food sector. In the United Kingdom alone, the estimated sales (by the Institute of GroceryDistributors) of functional foods in 2007 will be £1720 million. There has been a move toward gut flora modulation being a primary focus for diet and health perspectives. Hopefully, the important research avenues are identifiable to readers of

this handbook. What is clear is that many further opportunities exist. These include

• Effects systemic to the gut • Structure to function explanations of mechanisms of effect • New food product developments • Extrapolation into other areas of human and animal welfare • The development of new prebiotics, perhaps offering multiple

functionality • A generation of new variant probiotics that exploit the synbiotic

route • Improved knowledge of the symbiotic relationships between the

colonic microbiota and whole body physiopathology

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Science cannot progress without funding into appropriate research avenues. The prebiotics area has obvious commercial interest that has attracted sponsorship from the functional foods industry-as does probiotics. Historically this has been something of a “sea change” in that the food industry is not conventionally seen as major research sponsors when compared to pharmaceutical conglomerates. This has been criticized, but the independent nature of this work has helped propel the concept into mainstream science. Commercial sponsorship is easy to understand from the viewpoint of product initiatives; yet, as this handbook shows, the scientific value, understanding, and future perspectives of prebiotic research attracts many disciplines and discovery opportunities. Without such funding, the prebiotic concept itself would not exist-neither wouldmany research groups pioneering important diet, basic physiology, and health issues. On the contrary, prebiotic and probiotic research does not seem to be at all

attractive to themore traditional sponsors ofworldwide science (e.g., research councils, government bodies, health organizations, and food standards agencies). Perhaps “tradition” is the problem. The only exception to this is the EuropeanUnion, who through their lateral thinkingFrameworkProgrammes 4-6, have brought together much interdisciplinary expertise and answered many important questions. Their approach to food research is refreshingly proactive and not reactive, but sadly unique among the major sponsors. This is a pity, as the health impact is profound (e.g., the ubiquity of

gastrointestinal disorder is probablyuniversal, and the roles of an appropriate colonicmicroflora in health andwellbeing appearmore andmore important), the expertise is high-quality, crossingmanydisciplines and thefield ismoving quickly. The good news is that the research has happened anyway. However, it is rare that in little over a decade, there has been such rapid

progression, albeit seen as “puritan” by some parties. So, why is this? Our belief is that the prebiotic initiation correlated with, or even perhaps helped stimulate, a major development in bacteriology-specifically human gut microbiology. This was the advent of molecular-based procedures for identifying prokaryotic type, composition, and number. Examples largely include polymerase chain reaction (PCR)-based approaches to diagnostic molecules such as 16SrRNA. The research had coincidentally been provided with tools to robustly identify mechanisms of interaction applicable to human trials in large numbers, multiple laboratories, relevant clinical states, age groups, and across populations. Similarly, laboratory-based research could more closely identify mechanisms of effect and transpose studies into appropriate animal situations-often leading to significant developments in the companion pet industryandagriculturalpurposes (e.g., prebiotics arenowviewedas realistic alternatives to antibiotics in the farmyard). Where next? The prebiotics field is moving well and has attracted excellent

scientists (many of whom are represented here). However, there could be a new research development that even outstrips that of molecular approaches to gut microbiology and has prebiotics as the forefront. This is the science of “metabolomics.” Here, approaches such as high-quality nuclear magnetic

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resonance (NMR) and mass spectrometry have the ability to assess entire metabolic profiles in serum, urine, and feces and correlate these with gut microbial functionality. This is applicable to human and animal work, with the same generic approach that the output drives the technology. Indeed, the combined metabolic output of human metabolism and that of our resident bacterialmicroflora is nowknown as the humanmetabonome (J.K.Nicholson and colleagues). Here, it is suggested that the metabolic capacity of the gut microbiome is so vast that it impacts hugely overall upon human metabolism, thereby dictating the environmental impact of, for example, many food and pharmaceutical approaches. The questions that arise are major, with acute and chronic gut difficulties, cognitive disorders, metabolic syndrome, and obesity-related conditions all under investigation. Unlike our genetic makeup, the gut microbiota is amenable to change through diet. For prebiotics, this has been confirmed with reliable forms such as the inulin type fructans and, later, the galactans. For other candidates, the jury is still out, and much more evidence is needed. Nevertheless, the capabilities of prebiotic-induced gut microbiota change

are now known, as is the potential to determine metabonome impact. Coupling the two may mean that the prebiotic story for improving human health/well-being standards is only just beginning.