Federal Register / Vol. 66, No. 95 / Wednesday, May 16, 2001 / Rules and Regulations 27017

Action Compliance time Procedures

(ii) Parts become available from the manufacturer; or

(iii) Not more than three inspections or 1,200 hours TIS

go by: the first inspection would have to be accomplished upon accumulating the safe life; the second inspection would have to be accomplished within 400

hours TIS after accumulating the safe life; the third inspection would have to be accomplished 400 hours

TIS after the second inspection; and the replacement/

modification would have to be accomplished within

400 hours TIS after the third inspection (maximum

elapsed time would be 1,200 hours TIS).

(e) Can I comply with this AD in any other

way? You may use an alternative method of

compliance or adjust the compliance time if:

(1) Your alternative method of compliance

provides an equivalent level of safety; and

(2) The Manager, Fort Worth Airplane

Certification Office (ACO), approves your

alternative. Submit your request through an

FAA Principal Maintenance Inspector. The

inspector may add comments before sending

it to the Manager, Fort Worth ACO.

(3) Alternative methods of compliance

approved for AD 2000–14–51 are not

considered approved for this AD.

Note 2: This AD applies to each airplane

identified in paragraph (a) of this AD,

regardless of whether it has been modified,

altered, or repaired in the area subject to the

requirements of this AD. For airplanes that

have been modified, altered, or repaired so

that the performance of the requirements of

this AD is affected, the owner/operator must

request approval for an alternative method of

compliance in accordance with paragraph (e)

of this AD. The request should include an

assessment of the effect of the modification,

alteration, or repair on the unsafe condition

addressed by this AD; and, if you have not

eliminated the unsafe condition, specific

actions you propose to address it.

(f) Where can I get information about any

already-approved alternative methods of

compliance? Contact Rob Romero, Aerospace

Engineer, FAA, Fort Worth ACO, 2601

Meacham Boulevard, Fort Worth, Texas

76193–0150; telephone: (817) 222–5102;

facsimile: (817) 222–5960.

(g) What if I need to fly the airplane to

another location to comply with this AD? The

FAA can issue a special flight permit under

sections 21.197 and 21.199 of the Federal

Aviation Regulations (14 CFR 21.197 and

21.199) to operate your airplane to a location

where you can accomplish the requirements

of this AD provided that the following is

adhered to:

(1) Only operate in day visual flight rules

(VFR) only.

(2) Ensure that the hopper is empty.

(3) Limit airspeed to 135 miles per hour

(mph) indicated airspeed (IAS).

(4) Avoid any unnecessary g-forces.

(5) Avoid areas of turbulence.

(6) Plan the flight to follow the most direct

route.

(h) Are any service bulletins incorporated

into this AD by reference? Replacement

actions required by this AD must be done in

accordance with Snow Engineering Service

Letter #197, #202, #203, or #205, all Revised

March 26, 2001, as applicable. The Director

of the Federal Register approved this

incorporation by reference under 5 U.S.C.

552(a) and 1 CFR part 51. You may get copies

of this document from Air Tractor,

Incorporated, P.O. Box 485, Olney, Texas

76374. You can look at copies at FAA,

Central Region, Office of the Regional

Counsel, 901 Locust, Room 506, Kansas City,

Missouri, or at the Office of the Federal

Register, 800 North Capitol Street, NW, suite

700, Washington, DC.

(i) When does this amendment become

effective? This amendment becomes effective

on June 8, 2001.

Issued in Kansas City, Missouri, on May 7,

2001.

Melvin D. Taylor,

Acting Manager, Small Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 01–11968 Filed 5–15–01; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NE–42–AD; Amendment

39–12229; AD 2001–10–03]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company CF34 Series

Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to General Electric Company

(GE) CF34–1A, –3A, –3A1, –3A2, –3B,

and –3B1 turbofan engines. This action

requires a one-time inspection, and if

necessary replacement of certain fan

disks for electrical arc-out indications,

and assigns a reduction in the life limit

of certain fan disks. This amendment is

prompted by a report of a crack that was

found during a visual inspection as part

of routine engine maintenance. The

actions specified in this AD are

intended to prevent rupture of the fan

disk due to cracks that initiate at an

electrical arc-out, which could result in

an uncontained failure of the engine.

DATES: Effective May 31, 2001. The

incorporation by reference of certain

publications listed in the rule is

approved by the Director of the Federal

Register as of May 31, 2001.

Comments for inclusion in the Rules

Docket must be received on or before

July 16, 2001.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), New England

Region, Office of the Regional Counsel,

Attention: Rules Docket No. 2000–NE–

42–AD, 12 New England Executive Park,

Burlington, MA 01803–5299. Comments

may also be sent via the Internet using

the following address: 9-aneadcomment@faa.gov. Comments sent

via the Internet must contain the docket

number in the subject line.

The service information referenced in

this AD may be obtained from GE

Aircraft Engines, 1000 Western Avenue,

Lynn, MA 01910; Attention: CF34

Product Support Engineering, Mail

Zone: 34017; telephone (781) 594–6323;

fax (781) 594–0600. This information

may be examined at the FAA, New

England Region, Office of the Regional

Counsel, 12 New England Executive

Park, Burlington, MA; or at the Office of

the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Eugene Triozzi, Aerospace Engineer,

Engine Certification Office, FAA, Engine

and Propeller Directorate, 12 New

England Executive Park, Burlington, MA

01803–5299; telephone 781–238–7148;

fax 781–238–7199.

SUPPLEMENTARY INFORMATION: The FAA

has received a report of a crack at one

of the fan blade installation pin holes in

a GE CF34–3A1 engine fan disk. The

crack was found during a visual

inspection that was being conducted as

part of routine engine maintenance.

Crack initiation sites, consisting of small

zones of melted and resolidified metal,

27018 Federal Register / Vol. 66, No. 95 / Wednesday, May 16, 2001 / Rules and Regulations

have been discovered on fan disk

surfaces. Three additional burned zones

were observed adjacent to the crack site,

but crack propagation at those sites did

not occur because they were at lower

stress locations. Metallurgical

examination determined that these

defects were a result of inadvertent

contact by electrical probes used during

an electrochemical etching procedure

during manufacture. The defect is being

referred to as electrical arc-out. These

crack initiation sites may have occurred

at fan disk surface locations accessible

during part marking. Stress and life

analyses conducted by the manufacturer

show that if these sites occur at highstress locations on disks, then crack

propagation and rupture may occur

before the part reaches its published

low-cycle fatigue removal life. Also,

some disks have manufacturing records

that indicate blending, possibly of arcouts, was performed at initial

manufacture. This is referred to as a

blended callout. Because arc-outs that

may have occurred on these disks may

have been blended away, these disks

can not be reliably inspected for arc-out

using the visual methods developed for

other disks. Therefore, these disks must

be removed from service. This

condition, if not corrected, could result

in rupture of the fan disk due to cracks

that initiate at an electrical arc-out,

which could result in an uncontained

failure of the engine.

Manufacturer’s Service Information

The FAA has reviewed and approved

the technical contents of GE Aircraft

Engines (GEAE) Alert Service Bulletin

(ASB) CF34–BJ 72–A0088, Revision 1,

dated October 30, 2000; and ASB CF34–

AL 72–A0103, dated August 4, 2000.

These ASB’s provide procedures for

inspections of certain disks for electrical

arc-out indications, and if necessary,

replacement of the disk with a

serviceable disk.

Requirements of This AD

Since an unsafe condition has been

identified that is likely to exist or

develop on other CF34–1A, –3A, –3A1,

–3A2, –3B, and –3B1 turbofan engines

of the same type design, this AD is being

issued to prevent rupture of the fan disk

due to cracks that initiate at an electrical

arc-out. This AD requires an inspection

of fan disks P/N’s 5921T18G01,

5921T18G09, 5921T18G10,

5921T54G01, 5922T01G02,

5922T01G04, 5922T01G05,

6020T62G04, 6020T62G05,

6078T00G01, 6078T57G01,

6078T57G02, 6078T57G03,

6078T57G04, 6078T57G05, and

6078T57G06 for electrical arc-out

indications and, if necessary,

replacement of the fan disk with a

serviceable disk. This AD also requires

replacement of certain fan disks with

blended callouts that are listed by P/N

and SN in this AD before achieving a

new reduced life limit. The inspection

and replacement must be done in

accordance with the alert service

bulletins described previously.

Differences Between the Manufacturer’s

Service Information and This AD

Although fan disk P/N 5922T01G02 is

not specified by ASB CF34–BJ 72–

A0088, Revision 1, dated October 30,

2000, fan disk P/N 5922T01G02 is

subject to the requirements specified in

this AD.

Immediate Adoption of This AD

Since a situation exists that requires

the immediate adoption of this

regulation, it is found that notice and

opportunity for prior public comment

hereon are impracticable, and that good

cause exists for making this amendment

effective in less than 30 days.

Comments Invited

Although this action is in the form of

a final rule that involves requirements

affecting flight safety and, thus, was not

preceded by notice and an opportunity

for public comment, comments are

invited on this rule. Interested persons

are invited to comment on this rule by

submitting such written data, views, or

arguments as they may desire.

Communications should identify the

Rules Docket number and be submitted

in triplicate to the address specified

under the caption ADDRESSES. All

communications received on or before

the closing date for comments will be

considered, and this rule may be

amended in light of the comments

received. Factual information that

supports the commenter’s ideas and

suggestions is extremely helpful in

evaluating the effectiveness of the AD

action and determining whether

additional rulemaking action would be

needed.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the rule that might suggest a need to

modify the rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report that

summarizes each FAA-public contact

concerned with the substance of this AD

will be filed in the Rules Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 2000–NE–42–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Regulatory Impact

This final rule does not have

federalism implications, as defined in

Executive Order No. 13132, because it

would not have a substantial direct

effect on the States, on the relationship

between the national government and

the States, or on the distribution of

power and responsibilities among the

various levels of government.

Accordingly, the FAA has not consulted

with state authorities prior to

publication of this final rule.

The FAA has determined that this

regulation is an emergency regulation

that must be issued immediately to

correct an unsafe condition in aircraft,

and is not a ‘‘significant regulatory

action’’ under Executive Order 12866. It

has been determined further that this

action involves an emergency regulation

under DOT Regulatory Policies and

Procedures (44 FR 11034, February 26,

1979). If it is determined that this

emergency regulation otherwise would

be significant under DOT Regulatory

Policies and Procedures, a final

regulatory evaluation will be prepared

and placed in the Rules Docket. A copy

of it, if filed, may be obtained from the

Rules Docket at the location provided

under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Incorporation by reference,

Safety.

Adoption of the Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration amends part 39 of the

Federal Aviation Regulations (14 CFR

part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

2001–10–03 General Electric Company:

Amendment 39–12229. Docket 2000–

NE–42–AD.

Federal Register / Vol. 66, No. 95 / Wednesday, May 16, 2001 / Rules and Regulations 27019

Applicability

This airworthiness directive (AD) is

applicable to General Electric Company (GE)

CF34–1A, –3A, –3A1, –3A2, –3B, and –3B1

turbofan engines with fan disk part numbers

(P/N’s) 5921T18G01, 5921T18G09,

5921T18G10, 5921T54G01, 5922T01G02,

5922T01G04, 5922T01G05, 6020T62G04,

6020T62G05, 6078T00G01, 6078T57G01,

6078T57G02, 6078T57G03, 6078T57G04,

6078T57G05, and 6078T57G06 installed.

These engines are installed on but not

limited to Bombardier, Inc. Canadair airplane

models CL–600–2A12, -2B16, and -2B19.

Note 1: This AD applies to each engine

identified in the preceding applicability

provision, regardless of whether it has been

modified, altered, or repaired in the area

subject to the requirements of this AD. For

engines that have been modified, altered, or

repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (e) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance

Compliance with this AD is required as

indicated, unless already done.

To prevent rupture of the fan disk due to

cracks that initiate at an electrical arc-out,

which could result in an uncontained failure

of the engine, do the following:

Removal of Certain Fan Disks from Service

(a) On disk P/N’s 5921T18G01,

5921T18G09, 5921T18G10, 5921T54G01,

5922T01G02, 5922T01G04, 5922T01G05,

6020T62G04, 6020T62G05, 6078T00G01,

6078T57G01, 6078T57G02, 6078T57G03,

6078T57G04, 6078T57G05, and 6078T57G06,

that are listed by P/N and serial number (SN)

in the following Table 1 of this AD and that

have less than 8,000 cycles-since-new (CSN)

on the effective date of this AD, replace fan

disk P/N’s before accumulating 8,000 CSN:

TABLE 1. FAN DISKS THAT REQUIRE

REMOVAL BASED ON BLENDED

CALLOUTS

Disk part number Disk serial number

6078T57G04 ............. GEE09287

6078T00G01 ............. GAT3860G

6078T57G02 ............. GAT1924L

5922T01G04 ............. GAT9599G

6078T57G04 ............. GEE05831

6078T57G04 ............. GEE06612

6078T57G04 ............. GEE06618

6078T57G04 ............. GEE06974

6078T57G04 ............. GEE06980

6078T57G05 ............. GEE143FY

6078T57G05 ............. GEE1453G

6078T57G05 ............. GEE14452

6078T57G05 ............. GEE145NA

6078T57G04 ............. GEE08086

TABLE 1. FAN DISKS THAT REQUIRE

REMOVAL BASED ON BLENDED

CALLOUTS—Continued

Disk part number Disk serial number

6078T57G04 ............. GEE09287

6078T57G04 ............. GEE09337

6078T57G05 ............. GEE12720

6078T57G05 ............. GEE14214

6078T57G05 ............. GEE142YT

6078T57G05 ............. GEE146GT

(b) For disks with SN’s listed in Table 1 of

this AD that have 8,000 CSN or greater on the

effective date of this AD, replace the disk

within 30 days after the effective date of this

AD.

Inspection of All Other Fan Disks

(c) Inspect all other fan disks, P/N’s

5921T18G01, 5921T18G09, 5921T18G10,

5921T54G01, 5922T01G02, 5922T01G04,

5922T01G05, 6020T62G04, 6020T62G05,

6078T00G01, 6078T57G01, 6078T57G02,

6078T57G03, 6078T57G04, 6078T57G05, and

6078T57G06 in accordance with paragraphs

3.A.(1) through 3.E.(2) of the

Accomplishment Instructions of Alert

Service Bulletin (ASB) CF34–BJ 72–A0088,

Revision 1, dated October 30, 2000 or

paragraphs 3.A.(1) through 3.A.(2)(f) of the

Accomplishment Instructions of ASB CF34–

AL 72–A0103, dated August 4, 2000. Use the

compliance times specified in the following

Table 2:

TABLE 2. FAN DISK INSPECTION COMPLIANCE TIMES

Fan disk operating CSN Inspect by

(1) Fewer than 8,000 CSN on the effective date of this AD .................... Before accumulating 8,000 CSN or by the next hot section inspection

after the effective date of this AD, whichever occurs earlier.

(2) 8,000 CSN or greater on the effective date of this AD ....................... Within 120 days after the effective date of this AD.

Definitions

(d) For the purposes of this AD, the

following definitions apply:

(1) A serviceable fan disk is defined as a

fan disk that has been inspected as specified

in paragraph (c) of this AD and is not listed

in Table 1 of this AD.

(2) Cycles-since-new for fan disk P/N’s

5922T01G04 or 5922T01G05 is defined as

total cycles accrued since new as P/N

6078T57G02 or 6078T57G03, added to total

cycles accrued after modification from P/N

6078T57G02 or 6078T57G03.

Alternative Methods of Compliance

(e) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager, Engine

Certification Office (ECO). Operators shall

submit their requests through an appropriate

FAA Principal Maintenance Inspector, who

may add comments and then send it to the

Manager, ECO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this airworthiness directive,

if any, may be obtained from the ECO.

Special Flight Permits

(f) Special flight permits may be issued in

accordance with §§ 21.197 and 21.199 of the

Federal Aviation Regulations (14 CFR 21.197

and 21.199) to operate the aircraft to a

location where the requirements of this AD

can be accomplished.

Documents That Have Been Incorporated by

Reference

(g) The actions specified in this AD must

be done in accordance with the following GE

alert service bulletins:

Document No. Pages Revision Date

ASB CF34–BJ 72–A0088 ................................................................................................................... All ...... 1 October 30, 2000.

Total pages: 15

ASB CF34–AL 72–A0103 .................................................................................................................. All ...... Original August 4, 2000.

Total pages: 78

These incorporations by reference were

approved by the Director of the Federal

Register in accordance with 5 U.S.C. 552(a)

and 1 CFR part 51. Copies may be obtained

from GE Aircraft Engines, 1000 Western

Avenue, Lynn, MA 01910; Attention: CF34

Product Support Engineering, Mail Zone:

34017; telephone (781) 594–6323; fax (781)

594–0600. Copies may be inspected at the

FAA, New England Region, Office of the

Regional Counsel, 12 New England Executive

Park, Burlington, MA; or at the Office of the

27020 Federal Register / Vol. 66, No. 95 / Wednesday, May 16, 2001 / Rules and Regulations

Federal Register, 800 North Capitol Street,

NW., suite 700, Washington, DC.

Effective Date of This AD

(h) This amendment becomes effective on

May 31, 2001.

Issued in Burlington, Massachusetts, on

May 7, 2001.

Francis A. Favara,

Acting Manager, Engine and Propeller

Directorate, Aircraft Certification Service.

[FR Doc. 01–12006 Filed 5–15–01; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF HEALTH AND

HUMAN SERVICES

Food and Drug Administration

21 CFR Part 173

[Docket No. 92F–0396]

Secondary Direct Food Additives

Permitted in Food for Human

Consumption; Alpha-Acetolactate

Decarboxylase Enzyme Preparation

AGENCY: Food and Drug Administration,

HHS.

ACTION: Final rule.

SUMMARY: The Food and Drug

Administration (FDA) is amending the

food additive regulations to provide for

the safe use of alpha-acetolactate

decarboxylase (α-ALDC) enzyme

preparation derived from Bacillus

subtilis, modified by recombinant

deoxyribonucleic acid (DNA)

techniques to contain the gene coding

for α-ALDC from B. brevis, for use as a

processing aid to produce alcoholic malt

beverages and distilled liquors. This

action is in response to a petition filed

by Novozymes North America, Inc.

(formerly Novo Nordisk Bioindustrials,

Inc.).

DATES: This rule is effective May 16,

2001. Submit written objections and

requests for a hearing by June 15, 2001.

The Director of the Office of the Federal

Register approves the incorporation by

reference in accordance with 5 U.S.C.

552(a) and 1 CFR part 51 of a certain

publication in § 173.115(b)(3), effective

as of May 16, 2001.

ADDRESSES: Submit written objections to

the Dockets Management Branch (HFA–

305), Food and Drug Administration,

5630 Fishers Lane, rm. 1061, Rockville,

MD 20852.

FOR FURTHER INFORMATION CONTACT:

Rudaina H. Alrefai, Center for Food

Safety and Applied Nutrition (HFS–

206), Food and Drug Administration,

200 C St. SW., Washington, DC 20204,

202–418–3034.

SUPPLEMENTARY INFORMATION: In a notice

published in the Federal Register of

November 30, 1992 (57 FR 56585), FDA

announced that a food additive petition

(FAP 2A4345) had been filed by Novo

Nordisk Bioindustrials, Inc., later

renamed Novozymes North America,

Inc., 77 Perry Chapel Church Rd., P.O.

Box 576, Franklinton, NC 27525. The

petition proposed that the food additive

regulations be amended to provide for

the safe use of α-acetolactate

decarboxylase (ALDC) derived from B.

subtilis modified by recombinant DNA

techniques to contain the gene coding

for ALDC from B. brevis for use as a

processing aid in the brewing and

alcohol industries.

When FDA filed the petition in the

Federal Register of November 30, 1992

(57 FR 56585), it contained an

environmental assessment (EA). The

notice of filing stated ‘‘ * * * if the

agency finds that an environmental

impact statement is not required and

this petition results in a regulation, the

notice of availability of the agency’s

finding of no significant impact and the

evidence supporting that finding will be

published with the regulation * * *.’’ In

the Federal Register of July 29, 1997 (62

FR 40570), FDA published a final rule

on its National Environmental Policy

Act policies and procedures, which

became effective on August 28, 1997. In

a letter dated January 4, 2001, the

petitioner submitted a claim of

categorical exclusion under 21 CFR

25.32(k). The agency has reviewed the

claim of categorical exclusion and has

concluded that it is warranted.

I. Evaluation of Safety of the Petitioned

Use of the Additive

A. Introduction

The use of α-ALDC enzyme

preparation from B. subtilis is to prevent

the formation of diacetyl that causes

unpleasant taste in beer and other

alcoholic beverages. The enzyme αALDC is to be distinguished from the αALDC enzyme preparation, which

contains α-ALDC as the principal active

component in addition to other

components derived from the

production organism and fermentation

media. This document will refer to the

former as ‘‘α-ALDC’’ and the latter as

‘‘α-ALDC enzyme preparation.’’ Diacetyl

is normally formed from α-acetolactate

during fermentation. Alpha-ALDC,

which is the active component of the

petitioned enzyme preparation,

catalyzes the conversion of αacetolactate directly to acetoin, thereby

reducing the time needed for

spontaneous degradation of diacetyl to

acetoin.

B. Host Organism

The host organism, B. subtilis, for

production of α-ALDC is widely

distributed in nature and is commonly

present in foods eaten by both humans

and animals. It also has a history of safe

use as a source of enzymes in food

enzyme manufacturing industry prior to

1958. Thus, B. subtilis is considered to

be a nonpathogenic microorganism.

C. Donor Organism

B. brevis is the microorganism used as

the source of the genetic material for the

α-ALDC enzyme that is the subject of

FAP 2A4345. FDA reviewed the safety

of the DNA that encodes the enzyme αALDC from B. brevis and the enzyme it

produces (discussed below), because

only that DNA is transferred to the host

strain from the donor organism.

D. Production Organism

The petitioner provided information

demonstrating that the plasmid carrying

the gene for α-ALDC is stably integrated

into the chromosome of B. subtilis

production strain. The petitioner

conducted a study to evaluate the

pathogenicity of three B. subtilis strains.

In this study, mice received an

intraperitoneal injection with the B.

subtilis host strain, B. subtilis

production strain, and a B. subtilis

strain capable of producing α-ALDC but

not used as a source of the petitioned

enzyme preparation. FDA reviewed this

study as well as the scientific literature

concerning potential pathogenicity of B.

subtilis and did not identify any

microbiological concern (Refs. 1, 2, and

3).

E. Enzyme Preparation

The α-ALDC enzyme preparation is

manufactured by a submerged pure

culture fermentation of a genetically

engineered strain of B. subtilis carrying

the B. brevis gene that encodes α-ALDC.

The enzyme is secreted to the

fermentation broth and processed by

removing the cellular debris, followed

by concentration and formulation. For

certain applications, the α-ALDC

enzyme preparation is stabilized by

crosslinking with glutaraldehyde

(referred to as d-ALDC).

The petitioner submitted several

toxicological studies that address the

safety of the petitioned α-ALDC and dALDC enzyme preparations. These

include: A teratogenicity study in rats

and genotoxicity studies, including tests

for mutagenic activity in Salmonella

typhimurium and mammalian cells, as

well as tests for chromosome-damaging

activity in human lymphocytes. FDA

has reviewed these studies and

concludes that the petitioned α-ALDC