How the way an android checkbox when it check then convert to string and insert into database?

I have a little problem when i adding a checkbox in my app project, i hope when a checkbox selected or check, then it will be change to string and can be insert into mysql database. Any help would be appreciated. thank u.

Here my mainactivity code

private void addEmployee(){

    final String nama = editTextName.getText().toString().trim();
    final String pyg = editTextDesg.getText().toString().trim();
    final String tmpt = editTextSal.getText().toString().trim();
    final String tgl = Date.getText().toString().trim();
    final String jam = Waktu.getText().toString().trim();
    final Boolean email = Penting.isChecked();


    class AddEmployee extends AsyncTask<Void,Void,String>{

        ProgressDialog loading;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            loading = ProgressDialog.show(MainActivity.this,"Menambahkan...","Tunggu...",false,false);
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            loading.dismiss();
            Toast.makeText(MainActivity.this,s,Toast.LENGTH_LONG).show();
        }

        @Override
        protected String doInBackground(Void... v) {
            HashMap<String,String> params = new HashMap<>();
            params.put(konfigurasi.KEY_EMP_NAMA,nama);
            params.put(konfigurasi.KEY_EMP_PENYELENGGARA,pyg);
            params.put(konfigurasi.KEY_EMP_TEMPAT,tmpt);
            params.put(konfigurasi.KEY_EMP_TGL,tgl);
            params.put(konfigurasi.KEY_EMP_JAM,jam);
            params.put(konfigurasi.KEY_EMP_EMAIL, String.valueOf(email.equals("Penting")));

            RequestHandler rh = new RequestHandler();
            String res = rh.sendPostRequest(konfigurasi.URL_ADD, params);
            return res;

and this my php code to insert into database

<?php


if($_SERVER['REQUEST_METHOD']=='POST'){

    //Mendapatkan Nilai Variable
    $nama = $_POST['nama'];
    $desg = $_POST['pyg'];
    $sal = $_POST['tmpt'];
    $tgl = $_POST['tgl'];
    $jam = $_POST['jam'];
    $email = $_POST['email'];

    //Pembuatan Syntax SQL
    $sql = "INSERT INTO tb_pegawai (namaagenda,penyelenggara,tempat,tanggal,jam) VALUES ('$nama','$desg','$sal',str_to_date('".$tgl."', '%d-%m-%Y'),'$jam', '$email')";

    //Import File Koneksi database
    require_once('koneksi.php');

    //Eksekusi Query database
    if(mysqli_query($con,$sql)){
        echo 'Berhasil Menambahkan Pegawai';
    }else{
        echo 'Gagal Menambahkan Pegawai';
    }

    mysqli_close($con);
}?>