Ethereum account generation from seed

accounts.ts

const Web3: any = require('web3'); // tslint:disable-line:variable-name
const bip39: any = require('bip39');
const hdkey: any = require('ethereumjs-wallet/hdkey');

const web3: any  = new Web3();

export class Accounts {
  private seed: string;

  constructor(seed: string) {
      this.seed = seed;
  }

  private getSeed(): string {
    return this.seed;
  }

  getPrivateKey(index: number): string {

    const hdwallet: any = hdkey.fromMasterSeed(bip39.mnemonicToSeed(this.getSeed));
    const walletHdPath: any = "m/44'/60'/0'/0/";  // tslint:disable-line:quotemark
    const wallet: any = hdwallet.derivePath(walletHdPath + index).getWallet();
    const privateKey = wallet.getPrivateKey().toString('hex');
    return '0x' + privateKey;
  }

  getAddress(index: number): string {
    const privateKey: string = this.getPrivateKey(index);
    const account: any = web3.eth.accounts.privateKeyToAccount(privateKey);
    return account.address;
  }
}