Fruits come in an impressive array of shapes, sizes, and consistencies, and also display a huge diversity in biochemical/metabolite profiles, wherein lies their value as rich sources of food, nutrition, and pharmaceuticals. This is in addition to their fundamental function in supporting and dispersing the developing and mature seeds for the next generation.
Understanding developmental processes such as fruit development and ripening, particularly at the genetic level, was once largely restricted to model and crop systems for practical and commercial reasons, but with the expansion of developmental genetic and evo-devo tools/analyses we can now investigate and compare aspects of fruit development in species spanning the angiosperms. We can superimpose recent genetic discoveries onto the detailed characterization of fruit development and ripening conducted with primary considerations such as yield and harvesting efficiency in mind, as well as on the detailed description of taxonomically relevant characters.
This free review article focuses on two very morphologically distinct and evolutionary distant fruits: the capsule of opium poppy, and the grain or caryopsis of cereals. Both are of massive economic value, but because of very different constituents; alkaloids of varied pharmaceutical value derived from secondary metabolism in opium poppy capsules, and calorific energy fuel derived from primary metabolism in cereal grains. Through comparative analyses in these and other fruit types, interesting patterns of regulatory gene function diversification and conservation are beginning to emerge.
Sofia Kourmpetli and Sinéad Drea. The fruit, the whole fruit, and everything about the fruit. J Exp Bot. Apr 10 2014.
Anna Tiley, policy and communications intern at the Society of Biology, summarises events from the recent UK PlantSci 2014 conference held at the University of York. This post can also be found on the UK PlantSci blog.
Kew’s Global Kitchen Cookbook is an illustrated celebration of the amazing variety of edible plants and how we can use them. The range of edible plants is far broader than we may suppose, with huge variety, from all corners of the world, and continually changing in how they are used and perceived. Some now regarded as familiar were once exotic, such as tea, grapes and chillies, and the source of fortunes for those who ‘discovered’ and transported them, such as the staples of the Dutch East Indies spice trade – nutmeg, cinnamon and black peppercorns. An introduction gives context to the plants that provide the ingredients for the book’s 101 recipes featuring plants from around the world, including parsnip tart, truffle crepes, Cincinnati chilli, orange vacherin, Kashmiri curry, plantation smoothie, sweetcorn and crab fritters and pineapple cheesecake with chilli. A further section features the herbs of Europe and the Mediterranean and spices from the East, with details on how they grow, tips for growing windowsill box herbs, and how to use and combine different flavours to the best effect. Each plant has its own story of travel and adventure, and historical, botanical and economic themes are brought to life through the text and beautiful botanical illustrations from Kew’s archives. Relishing edible plants today needs to go hand in hand with acknowledging how lucky we are to have access to so much diversity, and how we need to preserve that for the future.
Sample recipe – Pineapple cheesecake with chilli
Native to South America, pineapples were first introduced to Europe by Columbus as the ‘pina de Indias’. Rich in manganese and vitamin C, delicious raw or cooked, they feature in many cuisines. This tasty dessert uses the pineapple’s sweet juice to balance the bite of hot chilli. Serves 6–8.
12 digestive biscuits, crushed
75g (3oz) unsalted butter, melted
40ml (8 tsp) pineapple juice
10ml (2 tsp) powdered gelatine
500g (1lb) cream (or curd) cheese
50g (2oz) icing sugar, sifted
60ml (2½fl oz) light rum
75g (3oz) caster sugar
10ml (2 tsp) fresh lime juice
¼ of a large, medium ripe pineapple (or ½ of a small/medium one), peeled and thinly sliced into bite-sized pieces
1 large red chilli, halved, de-seeded and finely chopped
- Mix the biscuit crumbs and butter and press on to the base of a 19cm (8in) spring-release tin. Chill.
- Put the pineapple juice and gelatine into a small saucepan and leave to soak for 2–3 mins, then warm over the gentlest heat until dissolved.
- Beat the cream cheese with the icing sugar, then slowly beat in the rum. Stir a spoonful of this mixture into the gelatine, and then slowly mix that back into the bulk of the cheese mixture. Spoon on to the biscuit base and level the surface. Cover and chill for at least 4 hours, or up to 24 hours.
- Meanwhile, dissolve the caster sugar in 100ml (3½fl oz) of water, then bring to the boil. Add the lime juice, prepared pineapple and chilli, and bring back to the boil. Immediately switch off the heat and leave the syrup to go cold.
- Remove the cheesecake from its mould and decorate the top with the drained pineapple. Serve the syrup separately.
AoB Blog welcomes the return of guest author, Charlie Haynes, who is currently a final year student in the School of Biological Sciences at the University of Leicester.
For around ten thousand years cereals have been a staple component of human diets. They are ubiquitous, with a cultural and religious significance to many. They permeate our diet. But the component that makes wheat so perfect for making bread dough, with its stretchy, elastic consistency, can also elict a severe autoimmune response for sufferers of coeliac disease.
Gluten proteins split into two subgroups; gliadin (soluble) and glutenin (insoluble), with gliadin proteins contributing the majority of epitopes associated with coeliac disease. The autoimmune reaction results in inflammation of the small bowel resulting in a damaging of the gut lining and vitamin malabsorption. Untreated it can lead to a quadrupling in mortality. And there has been a dramatic increase in prevalence of undiagnosed coeliac disease, with around 1 in 100 people in the UK now affected.
The only current treatment for coeliac disease is strict adherence to a gluten-free diet which is tricky. Gluten permeates the western diet, and there is evidence to suggest that a gluten free diet isn’t the shining beacon of health purported by health magazines. It can be high in fat, and deficient in iron, folate and calcium. Once patients are on a gluten free diet they often put on weight.
But not all gluten proteins contain the allergenic stimulatory epitopes. Various groups have been trying to decrease these epitopes whilst maintaining the technical properties important in bread making. Broeck et al investigated the effect of deleting individual gene loci in Triticum aestivum or chinese spring, the first wheat variety to have its genome sequenced. They were able to identify the specific gliadins that could remove stimulatory epitopes whilst maintaining structural properties (the ω-gliadin, γ-gliadin, and LMW-GS loci from the short arm of chromosome 1 of the D-genome, 1DS).
Barro et al were able to go further using RNA interference (a method of using RNA to prevent gene expression by destroying specific mRNA sequences) to down regulate expression of these gliadins. Gluten extracts from three of these transgenic lines samples were unable to elicit T cell responses and six others caused reduced responses.
This is groundbreaking work for coeliac patients. It means that we are coming closer to being able to marginalise the effect of coeliac disease in the day to day life of sufferers. Being able to have coeliac specialised wheat without any loss of technical properties will make it much easier for sufferers to enjoy more foods, and live more fulfilled, healthier lives.
A stem of Boswellia papyrifera in Ethiopia being tapped in order to collect frankincense, a gum-resin that the tree exudes when the bark is wounded. The resin, which is an impotant source of local income, is produced and transported by a network of canals that is limited to a narrow zone within the inner bark, a fact that can help to inform and improve tapping methods. See Tolera et al.
A reminder that a year after publication, Annals of Botany papers become free access. You can read about Boswellia tapping in Tolera et al’s paper, or you can see the issue’s contents page for somewhat more than just three wise men and women.
AoBBlog welcomes a new guest author, Charlie Haynes, who is currently a final year student in the School of Biological Sciences at the University of Leicester.
The search for healthy, gluten free and vegetarian alternatives to a traditional meat heavy diet has led to a massive increase in demand for the grain Quinoa (Chenopodium quinoa), native to the Bolivian highlands. The UN named 2013 the ‘year of quinoa‘. This is a resurgence for the grain after suppression since the colonial period, when spanish conquistadores scorned the grain due to its significance within religious ceremony. This exciting new grain and has quickly and suddenly become a fashionable food.
Quinoa is a pseudocereal from the family of Amaranthaceae and is unique in the major world grains, in that the edible part of the grain is the perisperm rather than the endosperm. It is coated in chemical saponins, which act as an antifeedant reducing plant palatability, and these are washed off during grain preparation for cooking. But it is a difficult crop to grow outside of the highlands of Peru and Bolivia; the two countries being responsible for almost 90% of global production.
John Brett in Food and Foodways; Explorations in the History and Culture of Human Nourishment discusses the impact of this increase of demand and the consequences of international food aid policy which contributes to the movement of excess commodities (such as wheat) to poor countries, and the movement of more nutritious local produce to wealthy countries. In the past those unable to afford more than very occasional animal protein have been able to supplement their protein intake with quinoa grain. But the skyrocketing of quinoa prices has left poorer urban Bolivians unable to afford it as over half the population is below the poverty line. As international demand for quinoa has caused a net movement of the product out of the country, the majority of US food aid is in the form of white flour which is severely lacking in the essential amino acids quinoa provides and is effectively ‘empty calories’. Despite Brett describing quinoa being rated as a food of high nutritional value in interviews, many said “it is too expensive”, and almost never consumed it. Brett noted that of fifty-seven 24-hour diet recall interviews only two respondents had included quinoa. Everyone mentioned white flour pasta or bread.
As demand for quinoa increased, public initiatives have been developed. This includes an agricultural intensification and income production programme, and a health and food security program. Yet while one was trying to build greenhouses for growing a variety of foods to increase dietary diversity, the other was trying to increase productivity and focus on those crops with the most marketability – quinoa.
Unfortunately these programmes are counterintuitive. Bolivia can take advantage of the sudden swelling of prices due to increased US and European demand (prices tripled between 2006 and 2011) and subsidise a greater variety of fruits and vegetables for those below the poverty line. Alternatively it can encourage the rural poor to grow a greater variety of vegetables themselves for dietary variety.
But it cannot do both.