[Angular] Pluck value from Observable

export class MailFolderComponent implements OnInit{

  title: Observable<string>;
  messages: Observable<Mail[]>;

  constructor(
    private route: ActivatedRoute
  ){

  }

  ngOnInit() {
      this.messages = this.route.data.pluck('messages');
      this.title = this.route.params.pluck('name')
  }
}