To export results you can rely on curl
and query your SPARQL endpoint through command line like this:
curl -X POST http://localhost:9999/bigdata/namespace/YOUR_NAMESPACE/sparql --data-urlencode 'query=SELECT * WHERE{ ?s p ?o } LIMIT 1' --data-urlencode 'format=json' > outputfile
You have to specify your endpoint's address of course and your query as you want. This is just an example but it may give you an idea.
Also you can modify your expected output format (CSV, XML, JSON, etc) and include headers if you want.
Here you can read more about it.