The negative number shows how much has to be risked to win aR$100 payout. Thus, if the money line for the team that you picked was -400, it means that if you placed a successfulR$400 bet, you would gainR$100 on payout.
The moneyline when placing a wager on a favorite tells you how much money you would be required to wager in order to return aR$100 profit on your bet. In the case of the Sharks (-230) is telling us that it would be necessary for you to betR$230 on San Jose if you desired to make aR$100 return from your wager.