**Exhibit 10.6**

**THIS NOTE AND THE COMMON EQUITY ISSUABLE UPON CONVERSION OF THIS NOTE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. THIS NOTE AND THE COMMON EQUITY ISSUABLEUPON CONVERSION OF THIS NOTE MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF (A) AN EFFECTIVE REGISTRATION STATEMENT AS TO THIS NOTE UNDER SAID ACT AND ANY APPLICABLE STATE SECURITIES LAWS OR (B) AN EXEMPTIONFROM SUCH REGISTRATION REQUIREMENTS.**

**SECURED CONVERTIBLE DEMAND NOTE**

 

FOR VALUE RECEIVED, PA LLC,a Delaware limited liability company (together with its successors, the “Maker”) promises to pay to PetroTech Holdings, Corp., (the “Payee”) on demand at c/o Laurus Capital Management, LLC, 335 Madison Avenue, 10th Floor, New York, New York 10017, or at such other place as may be designated in writing by the holder of this Convertible Demand Note, theprincipal sum (the “Principal Amount”) of SEVEN MILLION NINE HUNDRED SEVENTY SIX THOUSAND and 00/100 Dollars ($7,976,000.00), which sum shall all be payable in lawful money of the United States of America, together with interestthat shall accrue on the unpaid principal balance computed from the date hereof at twelve percent (12.0%) per annum. Interest shall be calculated on the basis of the actual number of days elapsed over a year of 360 days and shall be paid infull upon demand by Payee of repayment of the Principal Amount under this Note. 

The aggregate Principal Amount of thisConvertible Demand Note that shall be deposited into the Restricted Account (as defined in the Restricted Account Agreement, dated as of the date hereof by and among the Maker and LV Administrative Services, Inc., as administrative and collateralagent, (“LV”) for Payee (as amended, restated, modified, and or supplemented from time to time, the “Restricted Account Agreement”) is $7,976,000. 

1. DEFINITIONS. 

“Common Stock” shall mean the shares of stock representing the Parent’s common stock, $0.001 par value per share. 

“Conversion Shares” shall mean the shares of Common Stock to be issued upon conversions of principal, interest or fees hereunder and in accordance with the terms hereof. 

“Exchange Act” shall mean the Securities Exchange Act of 1934, asamended. 

“Fixed Conversion Price” shall mean $5.43. 

“Parent” shall mean PetroAlgae Inc., a Delaware corporation. 

“Principal Market” means the NASD Over The Counter Electronic Bulletin Board, NASDAQ Capital Market, NASDAQ NationalMarket System, American Stock Exchange or New York Stock Exchange (whichever of the foregoing is at the time the principal trading exchange or market for the Common Stock). 

2. USE OF PROCEEDS. The proceeds of the loan made pursuant to this Convertible Demand Note shall be used by Maker solely for working capital purposes.

3. OPTIONAL REDEMPTION IN CASH. The Maker may prepay this Convertible Demand Note (“Optional Redemption”) by paying tothe Payee a sum of money equal to the Principal Amount outstanding at such time together with accrued but unpaid interest thereon and any and all other sums due, accrued or payable to the Payee arising under this Convertible Demand Note (the“Redemption Amount”) outstanding on the Redemption Payment Date (as defined below). The Maker shall deliver to the Payee a written notice of redemption (the “Notice of Redemption”) specifying the date for suchOptional Redemption (the “Redemption Payment Date”), which date shall be no sooner than ten (10) business days after the date of the Notice of Redemption (the “Redemption Period”). A Notice of Redemption shallnot be effective with respect to any portion of this Convertible Demand Note for which the Payee has previously delivered a Notice of Conversion (as hereinafter defined) or for conversions elected to be made by the Maker pursuant to Section 5during the Redemption Period. The Redemption Amount shall be determined as if the Payee’s and Maker’s, as applicable, conversion elections had been completed immediately prior to the date of the Notice of Redemption. On the RedemptionPayment Date, the Redemption Amount must be paid in good funds to the Payee. In the event the Maker fails to pay the Redemption Amount on the Redemption Payment Date as set forth herein, then such Redemption Notice will be null and void. 

4. MAKER’S PAYMENT OF INTEREST ON OPTIONAL INTEREST PAYMENT DATES. 

a. Subject to the restrictions set forth below in this Section 4, commencing on June 1, 2009 and on the first business day ofeach succeeding September, December and March thereafter (each, an “Optional Interest Payment Date”) through the date of repayment in full of all amounts outstanding under this Note, the Maker shall have the right, but not theobligation, to pay all accrued and unpaid interest as of such Optional Interest Payment Date through the issuance by Parent of fully paid and non-assessable shares of Common Stock to the Payee at a price per share equal to the greater of(i) the volume weighted average price of the Common Stock for the fifteen (15) days immediately prior to the applicable Optional Interest Payment Date and (ii) the Fixed Conversion Price (the “Interest ConversionPrice”). 

b. Mechanics of Maker’s Conversion. In the event that the Maker elects to convert accruedand unpaid interest into Common Stock, the Maker shall give no less than five (5) business days written notice of such election by delivering an executed and completed notice of conversion in substantially the form of Exhibit A hereto(appropriate completed) (“Notice of

Interest Conversion”) to the Payee and Parent and such Notice of Interest Conversion shall provide a breakdown in reasonable detail of theaccrued and unpaid interest that are being converted. On each Optional Interest Payment Date and in accordance with its Notice of Interest Conversion, the Payee shall make the appropriate reduction to the accrued and unpaid interest as entered inits records and shall provide notice thereof to the Maker. Pursuant to the terms of the Notice of Interest Conversion, the Parent will issue instructions to the transfer agent within one (1) business day of the date of the delivery to the Payeeand Parent of the Notice of Interest Conversion and shall cause the transfer agent to transmit the certificates representing the Conversion Shares to the Payee by crediting the account of the Payee’s designated broker with the Depository TrustCorporation (“DTC”) through its Deposit Withdrawal Agent Commission (“DWAC”) system within three (3) business days after receipt by the Payee and Parent of the Notice of Interest Conversion (the“Interest Conversion Delivery Date”). In the case of the exercise of the conversion rights set forth herein the conversion privilege shall be deemed to have been exercised and the Conversion Shares issuable upon such conversionshall be deemed to have been issued upon the date of receipt by the Payee and Parent of the Notice of Interest Conversion. The Payee shall be treated for all purposes as the record holder of the Interest Conversion Shares, unless the Payee providesthe Maker or Parent, written instructions to the contrary. 

c. Additional Interest Conversion Mechanics. The numberof shares of Common Stock to be issued upon each conversion accrued and unpaid interest shall be determined by dividing that portion of the interest to be converted by the applicable Interest Conversion Price. 

5. PAYEE’S CONVERSION RIGHTS 

a. Optional Conversion of Payee. The Payee shall have the right, but not the obligation, to convert all or any portion of the issued and outstanding Principal Amount and/or accrued interest and fees due and payable into fully paidand non-assessable shares of Common Stock at the Fixed Conversion Price. 

b. Mechanics of Payee’s Conversion.In the event that the Payee elects to convert this Convertible Demand Note into Common Stock, the Payee shall give notice of such election by delivering an executed and completed notice of conversion in substantially the form of Exhibit Bhereto (appropriate completed) (“Notice of Conversion”) to the Maker and Parent such Notice of Conversion shall provide a breakdown in reasonable detail of the Principal Amount, accrued interest and fees that are being converted. Oneach Conversion Date (as hereinafter defined) and in accordance with its Notice of Conversion, the Payee shall make the appropriate reduction to the Principal Amount, accrued interest and fees as entered in its records and shall provide writtennotice thereof to the Maker within two (2) business days after the Conversion Date. Each date on which a Notice of Conversion is delivered or telecopied to the Maker and Parent, in accordance with the provisions hereof shall be deemed aConversion Date (the “Conversion Date”). Pursuant to the terms of the Notice of Conversion, the Maker will issue instructions to the transfer agent within one (1) business day of the date of the delivery to the Maker and Parentof the Notice of Conversion and shall cause the transfer agent to transmit the certificates representing the Conversion Shares to the Payee by crediting the account of the Payee’s designated broker with the DTC through its DWAC system withinthree (3) business days after receipt by the Maker and Parent of the Notice of Conversion (the “Payee Conversion Delivery Date” and 

together with the Interest Conversion Delivery Date, the “Delivery Dates” and each, a “Delivery Date”). In the case of theexercise of the conversion rights set forth herein the conversion privilege shall be deemed to have been exercised and the Conversion Shares issuable upon such conversion shall be deemed to have been issued upon the date of receipt by the Maker andParent of the Notice of Conversion. The Payee shall be treated for all purposes as the record holder of the Conversion Shares, unless the Payee provides the Maker or Parent, written instructions to the contrary. 

c. Additional Conversion Mechanics.

1. The number of shares of Common Stock to be issued upon each conversion of this Convertible Demand Note shall be determined by dividing that portion of the principal and interest and fees to be converted, if any, bythe Fixed Conversion Price. 

2. The Fixed Conversion Price and number and kind of shares to be issued upon conversion issubject to adjustment from time to time upon the occurrence of certain events, as follows: 

(a) If the shares of CommonStock are subdivided or combined into a greater or smaller number of shares of Common Stock, or if a dividend is paid on the Common Stock or any preferred stock issued in shares of Common Stock, the Fixed Conversion Price, as the case may be, shallbe proportionately reduced in case of subdivision of shares or stock dividend or proportionately increased in the case of combination of shares, in each such case by the ratio which the total number of shares of Common Stock outstanding immediatelyafter such event bears to the total number of shares or units of Common Stock outstanding immediately prior to such event. 

6. COVENANTS OFTHE PARENT. 

a. During the period that conversion rights exist hereunder, the Parent will reserve from its authorized andunissued Common Stock a sufficient number of shares to provide for the issuance of Common Stock upon the full conversion of this Convertible Demand Note, including, without limitation, all interest that may accrue hereunder over a three year term.

b. During the period the conversion right exists, Parent covenants and agrees that (i) the number of shares of CommonStock that may be issued upon conversion hereunder will be validly issued, fully paid and nonassessable, and will be free of any liens or encumbrances, (ii) all such issued and outstanding shares of Common Stock will be issued in compliancewith applicable state and federal laws. 

7. OTHER RELATED CONVERSION PROVISIONS. 

a. Issuance of New Note. Upon any partial conversion of this Convertible Demand Note, a new Note containing the same date andprovisions of this Convertible Demand Note shall, at the request of the Payee, be issued by the Maker to the Payee for the principal balance of this Convertible Demand Note and interest which shall not have been converted or paid. 

b. Rights of Equityholders. The Payee shall not be entitled to vote or receivedividends or be deemed the holder of the Conversion Shares or any other securities of the Parent which may at any time be issuable upon conversion of this Convertible Demand Note for any purpose, nor shall anything contained herein be construed toconfer upon the Payee, as such, any of the rights of a equityholder of the Parent or any right to vote for the election of directors or upon any matter submitted to equityholders at any meeting thereof, or to give or withhold consent to anycorporate action (whether upon the recapitalization, issuance of shares, reclassification of shares, change of nominal value, consolidation, merger, conveyance or otherwise) or to receive notice of meetings, or to receive dividends or subscriptionrights or otherwise, in each case, until the Delivery Date applicable to the respective Conversion Equity purchasable upon the conversion hereof shall have occurred as provided herein. 

c. Investment Representations. By acceptance of this Note, the Payee represents to the Maker and Parent and agrees that:

 
 (i)The Note is being acquired for the account of the Payee, and the Payee has no present intention of offering, selling, transferring or otherwise disposing of the Note or the sharesof Common Stock issuable upon conversion or exercise thereof. 
 
 (ii)The Payee will not sell, transfer or otherwise dispose of the Note or shares of Common Stock issuable upon conversion or exercise thereof, unless either: 
 
 (I)a registration statement under the Securities Act of 1933, as amended (the “Act”), covering such portion of the Note or such shares of Common Stock issued orissuable upon conversion or exercise thereof which is to be so offered, sold, transferred or otherwise disposed of has become effective; or 
 
 (II)the proposed offer, sale, transfer or other disposition of the Note or the shares of Common Stock issued or issuable upon conversion or exercise thereof are exempt from theregistration provisions of the Act. 
 
 (iii)Maker and Parent are under no obligation to register the Note or the shares of Common Stock issuable upon conversion or exercise thereof under the Act or any securities laws of anystate or take any action to make any exemption from such registration provisions available unless otherwise subsequently agreed in writing by the parties hereto. 

6. EVENT OF DEFAULT. The occurrence of any of the following events set forth in this section shallconstitute an event of default (“Event of Default”) hereunder: 

a. Failure to Pay. The Maker failsto pay on demand hereunder any of principal, interest or other fees hereon in accordance herewith, or the Maker fails to pay any of the other Obligations (under the Master Security Agreement, dated as of the August 21, 2008 (as amended,restated, modified and/or supplemented from time to time, the “Master Security Agreement”) by and between LV Administrative Services, Inc., as Agent (in its capacity as administrative and/or collateral agent, the“Agent”) and the Maker when due; or 

b. Breach of Covenant. The Maker or any of its subsidiariesbreaches any covenant or any other term or condition of this Convertible Demand Note, the Master Security Agreement or any other Document (as defined in the Master Security Agreement) in any material respect and such breach, if subject to cure,continues for a period of fifteen (15) days after the occurrence thereof; or 

c. Breach of Representations andWarranties. Any representation, warranty or statement made or furnished by the Maker or Parent, as applicable, in this Convertible Demand Note, the Master Security Agreement or any other Document (as defined in the Master Security Agreement)shall at any time be false or misleading in any respect on the date as of which made or deemed made; or 

d. Default Underthe Master Security Agreement. The occurrence of any default (or similar term) in the observance or performance of the Master Security Agreement or any other Document (as defined in the Master Security Agreement) or condition relating to anyindebtedness or contingent obligation of the Maker or any of its subsidiaries; or 

e. Bankruptcy. The Maker shall(i) apply for, consent to or suffer to exist the appointment of, or the taking of possession by, a receiver, custodian, trustee or liquidator of itself or of all or a substantial part of its property, (ii) make a general assignment for thebenefit of creditors, (iii) commence a voluntary case under the federal bankruptcy laws (as now or hereafter in effect), (iv) be adjudicated a bankrupt or insolvent, (v) file a petition seeking to take advantage of any other lawproviding for the relief of debtors, (vi) acquiesce to, any petition filed against it in any involuntary case under such bankruptcy laws, or (vii) take any action for the purpose of effecting any of the foregoing. 

f. Judgments. Attachments or levies in excess of $5,000 in the aggregate are made upon the Maker’s assets or a judgment isrendered against the Maker’s property involving a liability of more than $5,000.00; 

g. Insolvency. The Maker orany of their respective subsidiaries shall admit in writing its inability, or be generally unable, to pay its debts as they become due or cease operations of its present business; 

h. Change of Control. A Change of Control (as defined below) shall occur with respect to the Maker, unless Payee shall haveexpressly consented to such Change of Control in writing. A “Change of Control” shall mean any event or circumstance as a result of which (i) any “Person” or “group” (as such terms are defined in Sections 13(d) and14(d) of the 

Exchange Act, as in effect on the date hereof), other than the Payee, is or becomes the “beneficial owner” (as defined in Rules 13(d)-3 and 13(d)-5under the Exchange Act), directly or indirectly, of 35% or more on a fully diluted basis of the then outstanding voting equity interest of the Maker (other than a “Person” or “group” that beneficially owns 35% or more of suchoutstanding voting equity interests of the Maker on the date hereof), (ii) the Board of Directors of the Maker shall cease to consist of a majority of the Maker’s board of directors on the date hereof (or directors appointed by a majorityof the board of directors in effect immediately prior to such appointment) or (iii) the Maker or any of its subsidiaries merges or consolidates with, or sells all or substantially all of its assets to, any other person or entity; 

i. Indictment; Proceedings. The indictment or threatened indictment of the Maker or any of its respective subsidiaries or anyexecutive officer of the Maker or any of its subsidiaries under any criminal statute, or commencement or threatened commencement of criminal or civil proceeding against the Maker or any of its subsidiaries or any executive officer of the Maker or ofits subsidiaries pursuant to which statute or proceeding penalties or remedies sought or available include forfeiture of any of the property of the Maker, or any of its subsidiaries; or 

j. The Master Security Agreement. (i) An Event of Default shall occur under and as defined in the Master Security Agreement,(ii) the Maker or any of its subsidiaries shall breach any term or provision of the Master Security Agreement in any respect, (iii) the Maker, or any of its subsidiaries attempts to terminate, challenges the validity of, or its liabilityunder, the Master Security Agreement, (iv) any proceeding shall be brought to challenge the validity, binding effect of the Master Security Agreement or (v) without the consent of the Agent or the Payee, the Master Security Agreementceases to be valid, binding and enforceable obligation of the Maker. 

7. DEFAULT INTEREST. Following the occurrence and during thecontinuance of an Event of Default, the Maker shall pay additional interest on the outstanding principal balance of this Convertible Demand Note in an amount equal to two percent (2%) per month, and all outstanding obligations under thisConvertible Demand Note, the Master Security Agreement, including unpaid interest, shall continue to accrue interest at such additional interest rate from the date of such Event of Default until the date such Event of Default is cured or waived.

8. REMEDIES. During the continuance of any Event of Default, the Payee may in any applicable law, declare immediately due andpayable all or part of any obligation (including any accrued but unpaid interest thereon) under this Convertible Demand Note whereupon the same shall become immediately due and payable, without presentment, demand, protest or further notice or otherrequirements of any kind, all of which are hereby expressly waived by the Maker. 

9. AUTHORITY. The Maker represents that the Makerhas full power, authority and legal right to execute and deliver this Convertible Demand Note and that this Convertible Demand Note constitutes a valid and binding obligation of the Maker enforceable against the Maker in accordance with its terms.

10. DEFINED TERMS. Whenever used, the singular number shall include the plural, the plural the singular, and the words“Payee” and “Maker” shall include, respectively, their respective successors and assigns; provided, however, that the Maker shall in 

no event or under any circumstance have the right to assign or transfer its obligations under this Convertible Demand Note or the related documents, in wholeor in part, to any other person, party or entity. 

11. HEADINGS, ETC. The headings and captions of the numbered paragraphs of thisConvertible Demand Note are for convenience of reference only and are not to be construed as defining or limiting, in any way, the scope or intent of the provisions hereof. 

12. ENFORCEABILITY. The Maker acknowledges that this Convertible Demand Note and the Maker’s obligations under this Convertible Demand Noteare and shall at all times continue to be absolute and unconditional in all respects, and shall at all times be valid and enforceable irrespective of any other agreements or circumstances of any nature whatsoever which might otherwise constitute adefense to this Convertible Demand Note and the obligations of the Maker under this Convertible Demand Note or the obligations of any other person or party relating to this Convertible Demand Note. This Convertible Demand Note and the guarantees,security agreements, other agreements, instruments and documents executed and/or delivered in connection herewith (collectively and as the same may be amended or otherwise modified from time to time, the “Documents”) set forth theentire agreement and understanding of the Payee and the Maker, and the Maker absolutely, unconditionally and irrevocably waives any and all right to assert any setoff, counterclaim or crossclaim of any nature whatsoever with respect to thisConvertible Demand Note or the obligations of the Maker hereunder or thereunder, or the obligations of any other person or party relating hereto or thereto or to the obligations of the Maker hereunder or thereunder or otherwise in any action orproceeding brought by the Payee to collect this Convertible Demand Note, or any portion thereof, or to enforce, foreclose and realize upon the liens and security interests of the Payee in any collateral. The Maker acknowledges that no oral or otheragreements, conditions, promises, understandings, representations or warranties exist with respect to this Convertible Demand Note or with respect to the obligations of the Maker under this Convertible Demand Note, except those specifically setforth in this Convertible Demand Note. 

13. WAIVER. The Maker waives presentment, demand for payment, notice of dishonor and any orall notices or demands in connection with the delivery, acceptance, performance, default or enforcement of this Convertible Demand Note and consents to any or all delays, extensions of time, renewals, release of any party to any document related tothis Convertible Demand Note, and of any available security therefor, and any and all waivers or modifications that may be granted or consented to by the Payee with regard to the time of payment or with respect to any other provisions of any of theDocuments, and agrees that no such action, delay or failure to act on the part of the Payee shall be construed as a waiver by the Payee of, or otherwise affect, in whole or in part, its right to avail itself of any remedy with respect thereto. Nonotice to or demand on the Maker shall be deemed to be a waiver of the obligation of the Maker or of the right of the Payee to take further action without further notice or demand as provided in any of the Documents. 

14. ASSIGNABILITY. This Convertible Demand Note shall be binding upon the Maker and its successors and assigns, and shall inure to the benefit ofthe Payee and its successors and assigns, and may be assigned by the Payee. The Maker may not assign any of its obligations under this Convertible Demand Note without the prior written consent of the Payee, any such purported assignment without suchconsent being null and void. 

15. SECURITY. LV Administrative Services, Inc., as Agent, for the benefit of the Payee, hasbeen granted a security interest in certain assets of the Maker as more fully described in the Master Security Agreement. 

16.AMENDMENTS. This Convertible Demand Note may not be modified, amended, changed or terminated orally, except by an agreement in writing signed by the Maker, the Parent and the Payee. No waiver of any term, covenant or provision of thisConvertible Demand Note shall be effective unless given in writing by the Payee and, if so given by the Payee, shall only be effective in the specific instance in which given. 

17. GOVERNING LAW. This Convertible Demand Note is and shall be deemed entered into in the State of New York and shall be governed by andconstrued in accordance with the laws of the State of New York, without regard to principles of conflicts of laws. 

IN WITNESS WHEREOF, the Maker has duly executed this Convertible Demand Note the day andyear first above written. 

 
**PA LLC**
 
By: 
/s/    Ottmar Dippold
Name: 
Ottmar Dippold
Title: Chief Executive OfficerACKNOWLEDGED AND AGREED TO BY:**PETROALGAE INC.**By: 
/s/    David Szostak
Name: 
David Szostak
Title: President
SIGNATURE PAGE TO 

CONVERTIBLE DEMAND NOTE 

 

**EXHIBIT A**

**NOTICE OF INTEREST CONVERSION**

PetroTech Holdings, Corp. 

c/o Laurus Capital Management, LLC 

335 Madison Avenue, 10th Floor 

New York, NY 10017 

ATTN: General Counsel 

PetroAlgaeInc. 

[Address] 

The undersigned herebyconverts $                 of the interest due on [specify applicable Optional Interest Payment Date] under the Convertible Demand Note dated as of May    , 2009 (the “**Note**”) issued by PA LLC (the “**Company**”) to PetroTech Hldings, Corp. by delivery of shares of Common Stock of PetroAlgae Inc. (“**Shares**”) on and subject tothe conditions set forth in the Note. 

 
1.Date of Conversion                                                                        
 
2.Shares To Be Delivered:                                                                
 
PA LLCBy: 
 
Name: Title: 

**EXHIBIT B**

**NOTICE OF CONVERSION**

PA LLC 

[Address] 

PetroAlgae Inc. 

[Address] 

The undersigned hereby converts$                 of the principal and/or interest due on [specify applicable Repayment Date] under the Convertible Demand Note dated as of May    , 2009 (the “**Note**”) issued by PA LLC (the “**Company**”) by delivery of shares of Common Stock of PetroAlgae Inc. (“**Shares**”) on and subject to the conditions set forth inthe Note. 

 
3.Date of Conversion                                                                         
 
4.Shares To Be Delivered:                                                                 
 
[PAYEE]By: 
 
Name: Title: