Japan's Nikkei 225 widened losses to end at a one-and-a-half-week low.  Stocks with significant exposure to China such as construction equipment makers Komatsu and Hitachi Construction Machinery tumbled 2.9 and 2.7 percent, respectively. Steelmakers also extended losses, with JFE Holdings and Japan Steelworks plunging 7.1 and 3.9 percent, respectively.  Oil-related plays such as JX Holdings and Showa Shell Sekiyu lost 1.4 and 2.6 percent, respectively, as U.S. oil prices hover near six-year lows.  A strong quarterly report insulated Seiko Holdings from the sell-off; shares of the watch maker ended up 7.3 percent.  Australian shares dropped to a more than one-month low as the energy and resources sectors, which make up over 30 percent of the S&P/ASX 200 index, declined on the back of a rout in commodity prices.  Santos and Woodside Petroleum eased 4.9 and 3.8 percent, respectively, while index heavyweights BHP Billiton and Rio Tinto lost 5.4 and 4.3 percent, respectively.  However, advances among the gold plays offset some of the downward pressure. Evolution Mining and Kingsgate Consolidated bounced up 1 and 9.1 percent, respectively, as the price of the precious metal held near a three-week high in Asian trade.  Before the market open, Commonwealth Bank of Australia announced a 5 billion Australian dollar ($3.65 billion) rights issue to boost capital in response to regulatory pressure. Earlier, the lender delivered a 5 percent rise in full-year cash profit to A$9.14 billion, from A$8.68 billion a year earlier. Shares of the country's second-biggest lender are in a trading halt.  On the back of the announcement, Westpac, Australia and New Zealand Banking and National Australia Bank closed down nearly 2 percent each.  Among other companies releasing their corporate earnings, Computershare slumped nearly 10 percent after the investment service provider said its full-year net profit fell almost 40 percent. Gaming firm Echo Entertainment tanked 2.4 percent despite delivering a 59 percent rise in full-year net profit.
Asian equities headed further south on Wednesday, as the People's Bank of China allowed the yuan to extend sharp losses for the second straight day.